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SAE Formula Hybrid Team Mechanical Design Review (MDR) Report

Catherine Neely, Nick Steele, Dan Becker, Michael Rittmaster, Monserrat Mendez, Luc D’Andrea, Gabe Fagen, Zach Miller, Austin Ray, Tim LaGreca, Jack Mueller, and Carl

Doucette.

Advisor: Professor Jeffrey Helm

TABLE OF CONTENTS

Abstract ………………………………………………………………………………..……….…2

Team Mission Statement ………………………………………………………………....……… 2

Introduction………………………………………………………….………………......................3

1. Motivation…………………………………………………..……………………………....3

2. Current State of the Art……………..……….……………………………………………...5

3. Planned Approach………..…………………………………………….…………………...7

3.1. Chassis………..……………………………………………………………………..8

3.2. Suspension………..………………………………………………………………..10

3.3. Drivetrain………..……………………………………………………………....11

3.4. Interconnect………..…………………………………............................................13

3.5. TSV (Battery Packs)………..……………………………………………………...14

4. Roles and Responsibilities………..………………………………………………….....…16

5. Team Schedule………..…………………………....……………………...……………....21

5.1. Internal Deliverables……………………………………………………………....22

5.2. External Deliverables ……………………………………………………………..23

6. Required Resources……………………………………………….……………………….23

6.1. Operating Budget………………………………………………………………….23

7. Stakeholders and Partnership.………………………..........................................................25

8. Risk and Hazard Identification Management…………………...........................................26

8.1. Risk Assessment Matrix…………………………………………………………...29

Conclusion.………………………………………………………………………………………...29

SAE Formula One Hybrid Team 1

ABSTRACT

This report will inform its respective readers about the current state, preliminary and conceptual design for the Lafayette College 2019-2020 SAE Formula Hybrid team. This is a combined effort by mechanical engineering majors and electrical and computer engineers.

The Team is in the initial design stages of developing an electric formula car to participate in the Spring 2020 competition. The major goals of the team is to develop a competition rules compliant car through the following critical points: 1) complete the rolling chassis by December 3rd, 2) begin system testing by February 7th, and 3) take part in the 2020 FSAE competition in March.

This report presents the motivation for the project, the state of the art, the teams planned approach, corresponding roles and responsibilities, the team breakdown, the team schedule, required resources and stakeholders for the project, and a risk and hazard identification management plan.

A predominantly hands on a project of this magnitude and specificity requires a large team to tackle the tasks at hand. The conclusion came about that the only way this team could be successful was if it was properly separated into subsystems. The team of Mechanical Engineers has been divided into the corresponding subsystems, drivetrain, chassis, suspension, pedals, steering, interconnect, and a battery, Tractive System Voltage (TSV), team.

The chassis subsystem will be focused on modifying the chassis design from previous years and fabricating the firewalls and mountings for other subsystems. The suspension team will be working to manufacture A-arms, pushrods, and several other parts to ensure the rolling chassis will be finished by the December deadline. The drivetrain subsystem is focused on finalizing the motor, motor mount, differential, chain, and half shafts by making subtle modifications to last year’s design. The interconnect subsystem’s main concerns include creating enclosures, mountings, and connections between the Tractive System Interface (TSI), Grounded Low Voltage (GLV) and motor controller systems by working with the GLV and SCADA teams. The battery (TSV) subsystem is working on a complete battery redesign to develop two battery packs that will power the formula car with high voltage. The steering/pedal subsystem will be focused on finalizing the human control of the formula car. TEAM MISSION STATEMENT

The Lafayette College Formula SAE Racing Team is dedicated to designing, fabricating, testing, developing, racing, and implementing classroom knowledge and gaining innovative knowledge from that classroom knowledge. Lafayette Motorsports is a community-focused around designing, testing, manufacturing an electric racecar that passes the endurance test, passes the straight-line acceleration test by using the strength of past Lafayette teams, and improving aspects of their designs. Through interdisciplinary collaboration, the Lafayette Motorsports team hopes to reach a full circle by utilizing prior knowledge and applying that information to our team and future Lafayette teams. Teamwork, motivation, and communication are the driving factors that ensure our team’s success.


INTRODUCTION

In the report, a reader should expect to learn about the Lafayette College Senior Design Project for a combined mechanical and electrical engineering divisions for the 2019-2020 SAE Formula Hybrid Team. This Senior Design is a two-semester, 34 weeks, project. Our team is currently in the elementary stages.

Formula teams are graded on a variety of factors. The factors include a performance test, a project management plan, safety, reliability, manufacturing and assembly, serviceability, rain test, autocross course, straight-line acceleration test, endurance test, and innovation design.

The Formula Hybrid competition consists of a variety of dynamic and static events. Team responsibility includes creativity execution and utilizing project management skills for the project. Respective events are scored to determine how well our vehicle performed.

Three events make up the Dynamic portion of the competition: an acceleration test, an autocross test, and an endurance test. The Acceleration Test evaluates each vehicle on its accelerating abilities from a standing start in a straight line over a distance of 75 meters. The Autocross Test evaluates a car’s flexibility and ability to handle itself on a tight course without other competing cars on the track. The Endurance portion, which takes place on the New Hampshire Motor Speedway (NHMS) road course, puts the durability of each car in terms of acceleration, speed, dynamics, reliability, and handling, to the test under long-term distance conditions (44 kilometers). The Endurance portion is by far the most challenging.

The Static portion of the competition involves two events, Design and Project Management. The Design event provides students with the opportunity to explain their proposed solutions to both automotive and motorsport industry experts. This event produces an evaluation based on the engineering effort that went into the design of the car and how the engineering meets the competition intent. Judges look for organizational skills, effectiveness, and dynamic execution for the Project Management review. This component consists of three parts: a written project plan, an interim report, and a final presentation at the competition. 1

Our goal, as the Lafayette Formula Team, is to deliver a fully functional, rules compliant hybrid car at the Spring 2020 competition. The team is composed of 13 Electrical and Computer Engineers and 12 Mechanical Engineers. The schedule for this project is composed of only two semesters, and because of the extended interim break, getting as much done as possible before or by December is extremely important. Milestones for this project are included fully in the Work Breakdown section of the appendix, but significant dates for semesters end, include a finished prototype battery pack and rolling chassis. By the beginning of March, our team intends to complete two new battery packs and integrating all closed systems into a new car. Each year, though it may seem repetitive, a new team takes this project over and starts from scratch. While the new team can expand upon previous years, attention to detail and critical design thinking ensures the Lafayette team will only improve as the years go on.

1. MOTIVATION FOR PROJECT

Implications of our project for success are the challenge for our team to create a road-worthy vehicle, and that prevails over other designs at the competition. The determination of the project’s success is based on scoring events that determine the performance of our car. Other

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implications factors pertain to the design and the stakeholders involved. Implication factors include health, safety, welfare, global, cultural, social, environmental, and economic factors.

The concern of health and safety depends on the state of knowing that the driver is free from risks of danger, damage, or injury based on the testing of equipment. Welfare concerning this project results from the physical environment that accommodates a human activity, as in other team members, judges, and other teams watching the competition. Further discussion about health, safety, and welfare are located in Section 8.

Global, cultural, and social implications were considered and determined irrelevant to our project. Economic factors play a significant role in our team’s motivation. The team wants to learn how to budget a project and how to use said limited budget accordingly. Registration for our vehicle at the SAE Hybrid competition costs around $1300; this large price further encourages our team to work in an efficient and timely manner so that money does not go to waste.

Environmental factors pertain to our project. A few years ago, Lafayette Motorsports switched from a combustion engine to a hybrid car. Vehicles that run on oil and gas are a heavy burden on the environment, as they release chemicals and increase pollution in the Earth’s air. Switching to a hybrid vehicle, allowed Lafayette College to help tackle this problem. Our hybrid car releases fewer and cleaner wastes, which in turn result in smaller pollution levels.

The broad scope and comprehensive nature of building a hybrid car require each team member to develop and use both skills in the field of engineering and critical thinking. The interdisciplinary nature of the hybrid vehicle ensures proper use of communication between electrical and mechanical engineers, to promote a productive, communication based, disciplined, and well-organized working environment.

The team has six goals that drive the motivation for this project. Plan and manage an engineering design project: by creating a plan of how to manage an engineering design project, it will allow the team to be in control of the project instead of the project being in control of us. Demonstrate an understanding of the fundamentals of teamwork in terms of leadership, team orientation, mutual performance monitoring, backup behavior, and adaptability: this will be done by establishing roles and responsibility is another key to success. Understanding and gaining agreement on project objectives and deliverables, will ensure the project team, system engineers, and project management team agree on the work that is required. Demonstrate strong technical communication skills: Our team simply cannot function without communication. Communication skills force individuals to interact with project team members, decision makers, as well as other stakeholders. The improvement of communication skills will help this team, and is the key to success for this project. Likewise, our team members want to solve engineering problems and create engineering designs: Solving engineering problems is not a step by step process. In order to solve an engineering problem and create engineering designs, each member of a team must think about each of the important component that makes up the end goal of the project. Each member on the team must utilize and play to his or her strengths individually. Then as a team all these ideas combine and mesh together to create possible solutions to the engineering design. Our team prides ourselves on engaging in professional and responsible behavior during project work and demonstrate the capacity to grow professionally: These attributes allow our team to work as efficiently as possible. Task priorities can be assigned and the allocation of resources during project execution can be conducted smoothly.


2. DESCRIPTION OF CURRENT STATE OF THE ART

The Formula Car has been a recurring senior design project for eight years at Lafayette College. Lafayette recently switched from a combustion engine car to a hybrid; this change added a design challenge. Electrical and Computer Engineers are now thoroughly involved in the project, which models real-world work environments. The Motorsports team has continuously been redesigning, refabricating, and improving different subsystems of the car.

The formula car is designed by 12 mechanical and 13 electrical engineering students. This group of 25 competes against other undergraduate program vehicles. As the Project Manager for the Mechanical Engineers, an objective and contribution of mine are to structure and execute a project management plan that helps the team define and meet our goals. This plan ensures a functional, rules compliant race car on-time, that makes it easier to write future reports for SAE.

The Project Management Plan reflects upon the goals and objectives for the competition, the management structure, and tasks that will be completed to accomplish these objectives and the schedule over which the tasks are performed. The topics covered in the plan include scope, operations, risk management, expected results, and change management process. The crucial four are the scope, operations, risk management (which is commented on in Section 8), and the expected results. The scope includes planned accomplishments, significant deliverables, and milestones. The Operations section provides insight into the organization of the project team, work breakdown structure, project timeline, budget, and funding strategy. The Expected Results are the team goals and objectives quantified into a measurement of success.

This project heavily relies on the structural breakdown of the tasks. A combined project with Mechanical and Electrical engineers adds a level of complexity, which has been simplified into a visual in Chart One, that the team is motivated to undertake.

Chart 1: Breakdown of Major Systems. Mechanical Subsystems, Mechanical/Electrical Subsystems, and Electrical Subsystems.


Day one, the electrical and mechanical Project Managers, created a subsystem breakdown that ultimately would determine the success of our project. This team is one team; however, it would be virtually impossible to complete a goal of this complexity without assigning tasks. These subsystems needed to be broken down to “get stuff done.” The categories were established, and team members had the opportunity to pick what subsystem he or she desired to work on for the majority of the project. The Mechanical team needed and leader, and the Electrical team needed a leader independently. Project Managers oversee the entirety of the project.

The static and dynamic events that our team is tested on and the results of other teams in years past are the dictating factors that promote the level of competition. The 2019 Formula Hybrid Summary Score sheet, the Electric only class, is home to our team's competition for this year. The Electric only portion, displayed in figure 1 below, portrays what the Lafayette College team is competing against. Due to the fact Lafayette did not make it to competition last year, it seems unlikely that our team would be able to pull perfect scores in each category, the way competitors did last year. Instead, the table below averages each column, which is how it is going to attack this competition. A team goal is to score above the respective average documented below by making it to the competition. And a final goal is to get through the endurance test, which only one team successfully did last year. Our hopes of achieving above the reported averages below are to be reported in a future document that shows how well Lafayette achieved its respective benchmarks. 2

Figure 1: 2019 Formula Hybrid Summary Score Sheet - Only Relevant Information to Lafayette Motorsports

The Lafayette Motorsports team desires to be competitive and be a presence that other teams are competition is worried about. Critical thinking, leadership, teamwork, communication, and creativity are some of the essential factors while working in the field of engineering, and this project requires all of those skills from each team member. Our project should help future Lafayette Motorsport teams. Our team plans to expand upon previous years, attention to detail, and critical design thinking ensures this car team can only improve as the years go on.

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3. PLANNED APPROACH

For the Electric Competition, Lafayette College Motorsports is to assume a manufacturing firm has engaged our team to demonstrate a vehicle at the competition that was designed and fabricated by them. This vehicle is for a non-professional weekend autocross competitor. With this in mind, the car must be able to perform. Perform to be evaluated in terms of braking, handling qualities, and acceleration. The car should be low cost, easy to maintain, and reliable. Respective drivers should vary from a 5th percentile female to the 95th percentile male. The car’s marketability is to be aided by aesthetic factors and comfort factors. The challenge to the design team is to develop a prototype car that best meets these goals and intents. Each design is compared and judged with other competing designs to determine the best overall car. 3

So, this is the Lafayette College Motorsport team’s problem. The pressing question still waits to be answered, how will the team’s well-defined and reasonable design achieve these objectives. The information to follow provides relevant information about the engineering metrics and specifications for the team’s design while including information about the subsystems and their interactions.

The Lafayette College team has decided to engineer a formula car by dividing itself into eight subsystems. These subsystems consist of: suspension, drivetrain, chassis, steering/pedals, battery, interconnect, SCADA, and grounded low voltage. Members of each subsystem are responsible for the development of the majority of each subsystem’s electronics/mechanics. However, there is a large amount of coordination between subsystems to ensure the team’s success (i.e., both the chassis and the battery teams work together to create the firewall to cover the batteries and mounting that attach the batteries to the chassis itself).

The chassis subsystem is to focus on modifying the chassis design from previous years and fabricating the firewalls and mountings for other subsystems. The suspension team works to manufacture A-arms, pushrods, and several other parts. This is all to ensure the December deadline marks the completion of the rolling chassis. The drivetrain subsystem focuses on finalizing the motor, motor mount, differential, chain, and half shafts by making subtle modifications to last year’s design. The interconnect subsystem’s primary concerns include creating enclosures, mountings, and connections between the Tractive System Interface (TSI), Grounded Low Voltage (GLV), and motor controller systems by working with the GLV and SCADA teams. The battery (TSV) subsystem is working on a complete battery redesign to develop two battery packs that power the formula car with high voltage. The steering/pedal subsystem is focused on finalizing the human control of the formula car.

The 2019-2020 Mechanical Team is under the following leadership structure: Faculty Advisor - Professor Helm, Project Manager - Cat Neely, System Engineers - Nick Steele and Dan Becker, Financial Officer - Monserrat Mendez, and Inventory Officer - Zach Miller. Utilizing this leadership, as well as the network of other Lafayette College professors and FSAE team alumni, the 2019-2020 SAE Formula Hybrid Team ensures success at the 2020 March competition.

Identification of essential missing components from the current products and systems at hand is in the works. The Chassis subsystem is missing GLV and TSI mounts, and the driver display mount and firewalls. The body panels on the outside of the car frame are also missing. The TSV subsystem is currently working on the battery housing, which relieves the battery mounts from the chassis subsystem. The Suspension subsystem is missing the rear suspension

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components. The Drivetrain subsystem just purchased the radiator, pump, tubing, and fitting components for the cooling system. A Cable subsystem has been implemented to ensure the safety team and works on the mechanical connections for the wiring of the car.

3.1. Chassis

The chassis system is unique because it interacts with every other system. This means effective and consistent communications between other groups and the chassis group is essential for the chassis to allow the other systems to operate at full functionality.

The chassis allows respective subsystems to fully function without interference. Safety measures, ergonomics, and system mountings are significant components of the chassis. Safety measures include roll hoops and a front impact attenuator to protect the driver in the event of a crash and firewalls to protect against potentially hot systems in the car. Providing space and adjustments for driver comfort is especially important for longer races, like the endurance event, and helps the driver operate the car better. The chassis team has decided to improve and add on to the last team’s designs, including widening the cockpit, adding firewalls, and adding mounts for the other systems.

Figure 2: Main frame of chassis

Significant aspects of the chassis are shown in figure 2 above, which was manufactured

over the summer of 2019. The chassis has been reviewed and checked for compliant rule issues, and it is now clear what necessary alterations must be made to ensure a rules compliant chassis. Four side impact members are being taken out and replaced with newly designed bent members, shown in figure 3 below, to widen the cockpit by three inches at the widest point, and four support members are being added to the frame to reinforce the bent members. The steering column is also being moved forward one inch to make room for a suspension mounting point. Moving the steering column forwards requires new drilled holes and pieces designed to hold it in place.


Figure 3: New Bent Side Impact Member

A primary design goal is the mountings for each system to the chassis. The suspension is

an integral subsystem that determines many aspects of how to design the chassis. Suspension mountings are the most complicated aspect; there are many necessary attachments points, and the preciseness of those attachment points makes the job all the more difficult. The 16 total mounting points for the A-arms comprise the majority of them. These locations of the mounting points are at nodes on the chassis frame (where different frame members connect).

Likewise, the seat mounting is a technical aspect of the chassis. Consideration of the position and angle with regards to comfort and rules compliance limit the variations of how the seat and be designed. The seat is connected to adjustable rails to make operating the pedals possible for people of different height. The seat position is going to be angled further back than initially intended to make more room for the driver’s legs in the relatively small front bulkhead.

Mountings for the TSV - Tractive System Voltage, have two components: flats for the battery housing to rest on, and locations for bolts to be inserted, securing the housing to the chassis frame. The flats are angled above the horizontal; this is because the side housing spaces were designed with a downward slope. Bolts are to be secured at the front and back of the motor housing to reduce front to back motion when the car accelerates, an important consideration given the TSV’s significant mass (an estimated 100 pounds each).

The chassis team plans on improving on the TSV mounting designs from previous years. There is a limited area usable for mounts due to the housing area geometry, and we have a goal to make it easier to take the battery housing in and out of the car. The typical rods securing the housing to a mount welded onto the chassis do not allow for any play in the housing position, and lining up a bulky, hundred-pound box with small holes is time-consuming. Making the rear mounts be able to shift into place, then lock reduces the need to shift the housing as much once it is placed into the chassis.

The side and rear firewalls that enclose the cockpit are a significant component for safety and rules compliance for the chassis. Firewalls protect the driver from potentially high-temperature components, most notably the batteries. The side firewalls are more complicated because of the bent side impact members and supports. One possible simplification would be to have each firewall be multiple pieces, broken up at the bent portion of the frame members, and sealed with brackets or by welding. This approach eliminates the need for curved firewalls.

The subsystem’s primary goal is to have a chassis optimized for each subsystem’s needs and requirements to allow the full functionality of those systems. Specifically, this goal targets special needs of systems and drivers, correct and easy to access mounting locations that provide subsystems with the ability to operate fully, and safety requirements that make the chassis rules compliant and lower the risk of driving the car.


3.2. Suspension

The main objectives for the suspension team have been to work through last year's designs, making adjustments and new designs as needed or manufacturing parts that fit the current needs of the 2019-2020 car. After initial investigations, we decided to redesign the a-arms and uprights, while adjusting the designs for any mounts or attachments accordingly. Additionally, the steering system designed by the 2018-2019 team will be updated accordingly. This will be done to ensure brake safety, and update the pushrods, dampers, and bellcranks and their respective mounts. Throughout our redesign, we have to keep a few significant rules and constraints in mind. First, the confirmation that the wheels on all four corners protrude past the battery boxes. Second, evidence that the suspension has a jounce and rebound of 50.4mm. Lastly, evidence that there is 25.4 mm of ground clearance.

For the a-arms, the significant component we decided to redesign was the a-arm plate. In the past, spherical bearings were pressed into these plates, and plates were welded on top to avoid the bearings falling out. This design made bearing failures quite common, so for this year, we decided to design the plates for weld-cups. These cups, displayed in figure 4 below, hold the bearings in via a machined lip and a c-clip. The a-arm plates were redesigned to hold this larger weld-cup while still maintaining the needed geometries for the arms. We also set out to redesign mounts for the uprights due to the larger diameter and height of the cups to allow for proper steering clearance and a-arm articulation.

Figure 4: New A-Arm Design

Additionally, our subsystem has been working to simplify the upright designs previously

implemented. The previous design, though functional, created several issues due to its complexity. We plan to achieve a more straightforward design by designing the uprights by removing the portions of the old upright that were designed to allow for the suspension to be tuned. If event tuning is required, the replacement of the corresponding plates is updated. New designs are based around rapid prototyping ability. Our newly designed plates use ¼ inch thick steel, which can be used with waterjet cutting to manufacture parts at low cost quickly. This reduces the issues had in previous iterations of this design by removing the parts that have failed frequently.


The safety of the steering rack is a primary concern, due to the exposed gear teeth to the bottom of the car. The cover design is fundamental as it protects the driver’s legs from being caught in addition to protecting the rack from track debris, which could damage or jam the steering rack, putting the driver at risk of crashing. The design of this year’s chassis creates a unique challenge as space in the nose of the car is limited, requiring the cover to be minimalist in size while accomplishing its design metrics.

The brakes remain mostly unchanged from last year. Our primary goal is to replace broken parts and modify the current assembly to allow for easier disassembly at the competition. The brakes that are currently attached to the car are more than adequate for the speeds the car can travel at.

The design of the pushrod and spring damper system is very similar to the design from last year. The main challenge is how different the nose of the chassis compares to last year. This means that the main objective is fitting the old system to the new chassis. Bellcrank mountings and dampers fit nicely to respective joints of the chassis in line with the centerline of the A-arms and the uprights. New bellcranks have been designed to fit the car, and longer pushrods have been designed to reach from the new A-arm plates to the bell cranks. These new designs allow the system to fit the dampers to chassis and the bell cranks without having to be adjusted to much since they are calibrated from last year's car to fit the regulations. The min constraint with the pushrod system is making sure it is rule compliant with the 50.4mm motion requirement up and down stated in the rules through jounce and rebound. It is hard to measure the ability of the system's compliance with this, especially since last year's suspension had a significant role in it without engaging the pushrod system at all. Since our updated system aims to remove this excess play, our accordance with the rules becomes more strict. However, since the springs and dampers have been well-calibrated and fit well into the new design for the new chassis nicely, only minor adjustments should be needed to be rule compliant, if it needs any at all.

Our design is tested by using finite element analysis and by on-vehicle testing. Discussion of the suspension design is to be readily updated to the team, Professor Helm, and Rob, our mechanical technician. Additionally, previous designs and reports will be used to educate ourselves on what has worked well for previous teams.

Our team's respective goals are to add a rear pushrod and bell crank mounting system to the car because that is something last year's team did not quite get to last year's full assembly. So bell cranks are designed but do not exactly have a place to go, and thus, pushrod measurements are hard to determine. A new A-arm plate design was also a goal for suspension because last year's design ran into problems and would not exactly fit or work well for this year's car. This new plate allows for upgraded spherical bearings and for an easier to assemble A-arm, along with working well with the new mounting system design for the uprights. All of this should allow for an easier to assemble a suspension system that fits the new chassis nicely and functions better than last year's system. More attention to reducing the play in the suspension through newly designed spacing systems for the spherical bearings and the chassis mounting systems should bring us towards a much-improved suspension system that is easier to assemble and is much more robust.

3.3. Drivetrain The drivetrain subsystem design objectives are to create a fully functional drivetrain with

an integrated cooling system that is both reliable and rules compliant. The drivetrain system is the


portion of the car that converts the power into torque. This torque is sent to the wheels. The integral parts of the drivetrain consist of the motor, motor mount, differential, chain, and half shafts. Last year's team already completed the motor mount; however, after the initial inspection, it appears alterations must be made to allow for easy integration with the motor's power cables as well as the cooling system inlet and outlet hoses. In addition to correctly mounting the motor to the car, we need to improve and fix some decisions made by last year's team. A differential adapter was incorrectly installed to the differential and became stuck. Rob Layng, our engineering technician, helped us to remove the adapter, but we needed to improve the design to meet the requirements for fasteners and to fix an issue with the clearances. A new design has been submitted and approved, and we hope to have the differential installed soon so we can begin to attach the half-shafts.

To develop a cooling system that allows our car to perform without overheating, we need to calculate how much heat the motor and motor controller create when at maximum conditions. These calculations include heat transfer formulas for a heat exchanger as well as using the efficiency of the motor and motor controller to find heat outputted. To correctly determine the amount of heat we need to remove from the motor and motor controller, we have been in contact with Professor Steffens, who specializes in Heat Transfer and Fluid Dynamics.

Figure 5: Drivetrain Design

The cooling system consists of a radiator, tubing, a water pump, and possibly fans to keep

air flowing to the radiator at low speeds. The radiator poses a challenge both technically and spatially. Motors in the past required air cooling, which negated the need for a radiator directly connected to the motor; however, our new motor the Emrax 208 does not have openings in the external housing for cooling. Instead, the Emrax 208 has an inlet and outlet openings for coolant that runs between the coils.

The team chose to add more complexity to this project. A car must simulate rainy conditions to pass the rain test. The only part of the drivetrain affected by rainy conditions is the cables connecting the motor controller to the motor. To prevent issues caused by possible grounding due to water, the implementation of a watertight housing to prevent water from


touching the connections. The rules also require that all connections must have some strain relief, which is implemented into the watertight cable housing.

The main constraints that are required for the drivetrain by the Formula SAE Electric judges are the use of rules compliant fasteners, the guarding required for the chain in the event of an ejection, and strain relief on all cables.

Our goals for the year include both new designs and improving on designs from last year's team. The differential adapter is in the process of updating. A shelf for the sprocket to sit on, and the addition of helicoils reduce clearance issues on the differential. First, all fasteners must be confirmed as rules compliant and as safe as possible. The answer, a new water-cooling system that cools both the motor and the motor controller installation. The motor needs waterproof housing, which should also provide some strain relief for the cables going into the motor. Making sure all aspects of the drivetrain are rules compliant requires us to design and manufacture a guarding for the motor, chain drive, wiring, and sprocket. All parts from last year's car are to be tested to make sure they are rules compliant. After the motor housing meets our standards, the installation of the half shafts and hubs can take place.

3.4. Interconnect The primary design objectives of the ME Interconnect team are to design, manufacture and

install an electrical enclosure for the Tractive System Interface (TSI), Grounded Low Voltage (GLV) and Motor Controller systems. In addition, the mechanical team will assist in the design and implementation of other low voltage electronics. Namely, buttons, light fixtures, keys dashboards and strain relief. These are secondary goals that the team will focus on after the enclosure is finished and the electrical systems are closer to being finished.

Interconnect team goals for the short term include the following. Finish overall enclosure by completing a panel design with proper holes for connectors. Update and improve last year’s relay board by adding horizontal bus bars and fuse holders to bus bar. Design proper shelving location and structure. Manufacture isolation walls by checking for proper material in the rules and potentially measure the real one for guidance. Add DIN Rails for TSI relays. And finally, confirm overall enclosure design with TSI, GLV and SCADA teams.

In order to complete these goals in a timely, efficient and effective manor the team is engaged in a rigorous brainstorming, design and revision process. This includes a series of design reviews with the TSI, GLV, and SCADA teams as well as the mechanical and electrical engineering professors. As of late September 2019, the Interconnect team has an approved preliminary design, as depicted in figure 6, and will continue to add detail and make revisions through October. The Goal is a finished enclosure by the start of November 2019. Once finished the team will focus on other interconnect projects like mounting low voltage electrical components.


Figure 6: Proposed Enclosure Design

The team has identified several engineering metrics and goals for the design of the

enclosure. Primarily, this is rules compliance. The enclosure contains both low voltage and high voltage zones and thus they must be separated appropriately. In addition, the design will focus on accessibility and ease of access to as much of the electronics as possible. In order to do this the team is implementing sliding shelves for the GLV and TSI systems. Lastly, the team would like to build the enclosure as water resistant as possible in order to pass the rain test.

3.5 TSV (Battery Packs)

TSV is an acronym that stands for Tractive System Voltage. The TSV team is responsible for bringing the accumulator to fruition. The accumulator is the enclosure that houses all battery cells and the electrical paths that carry the cells’ electrical power to the Motor Controller. Safety and ergonomics are critical elements of which the team is always conscious. Safety measures include adequately insulating the accumulator to prevent electrical shorts and ensuring structural equivalency to withstand large horizontally and vertical accelerations. Ergonomic aspects of the design include logical, electrical paths and cable management, as well as consideration for ease of assembly and disassembly of the accumulator.

The goal of the TSV team is to deliver a rules-compliant and logically developed accumulator. There are two main design objectives for this year’s team. First is an enclosure that completely separates all high and low voltage systems. Second is an accumulator that can withstand 40G of acceleration horizontally and 20G of acceleration vertically without breakage of any component or mount.

To make a logically developed accumulator, the team intends to follow the design principle of working from outside to inside. Ergonomics and mindfulness of physical space is accounted for


at the beginning of the design process. Through these restrictions due to pre-placed objects on the exterior, the team can simplify the interior.

To meet the isolation requirement for high and low voltage systems, the team has chosen one insulating material: garolite. In choosing garolite, its rigidity allows the TSV unit to withstand the acceleration tests, while still insulating the differing voltage systems.

The accumulator unit should have a footprint that is not excessively large as the real-estate in the side carriages is of value to other subsystems such as Drivetrain, who seek to install a cooling system and need space for radiators and fans. TSV must also remember that many cables occupy the rear three-quarters and the need for a firewall that shields them. The consciousness of space is always valued.

Figure 7: Proposed Accumulator Design

The TSV team has completed initial design concepts and is working towards creating a

prototype accumulator. This accumulator prototype serves as the first iteration of the battery pack design and is expected to be and assembled and completed by November 1, 2019. Design reviews for the prototype takes place throughout this process, starting the week of September 30, 2019.

Once assembled, evaluation of the prototype for performance, functionality, and rules compliance. Needed revisions are updated, and two mirroring battery packs plan to be fabricated by January 24, 2020. These two battery packs are expected to be the final battery packs used for competition and modifications as needed throughout later testing.

Engineering metrics and specifications for TSV design primarily come from the SAE Hybrid 2020 competition rules. The majority of these rules relate to safely insulating high voltage circuitry, isolating high voltage and low voltage battery pack components, having the battery packs be weather resistant, and withstanding 40 and 20 Gs of force in the vertical and horizontal directions, respectively. Other design metrics relate to ease of use when it comes to activities relating to opening the battery packs, such as replacing parts and troubleshooting.

The team is working toward delivering the prototype for the accumulator on December 1st, 2019. By setting the delivery date much earlier than needed, the team hopes to obtain feedback and criticism. An early prototype delivery allows for the final iteration to be fundamentally better.

In conclusion, the appropriateness of these constraints and benchmarks of the Team’s proposed design have been evaluated to the best of the Team’s ability.

4. ROLES AND RESPONSIBILITIES


In order to meet project objectives and to stay time efficient team members have been

assigned appropriate and relevant roles. The roles are referenced in Chart 2 include: a Project Manager, System Engineers, a Financial Officer, and an Inventory Officer. Further, respective subsystems and the corresponding breakdown, referenced in Chart 3, were created and are held responsible for the design, development, manufacture and implementation of that subsystem.

Chart 2: Relevant Roles Breakdown

Chart 3: Mechanical Team Breakdown, Respective System Engineers and Corresponding Subsystems


System Engineers: Dan Becker and Nick Steele The overall job of the system engineers is to oversee all systems on the car and aid each of

the subsystems listed below in completing all their technical requirements. Any technical questions or concerns can be brought to the system engineers for review to ensure they will meet requirements and fit in with all other systems in the car. Suspension: Dan Becker, Carl Doucette, and Zach Miller

The suspension team is in charge of designing and assembling all necessary suspension parts for the car. These parts include but are not limited to a-arms, pushrods, dampers, uprights, hubs, brakes, and control rods. The team must ensure that all parts and dimensions meet requirements set out by the rules and that the suspension will allow the car to perform well at competition. Goals:

● Rear push-rod/bell crank mounting system ● New A-arm plate design ● Simplification of upright mounting system ● Better spherical bearings ● Eliminate play in mounts ● Rules compliance

TSV: Tim LeGreca and Jack Mueller -

The team is responsible for delivering electrical energy to the motor. The enclosure responsible for housing the governing electrical equipment is also under the team’s jurisdiction. The team must safely and efficiently deliver the electrical current to the motor controller. Goals:

● GLV/TSV Simplification ○ Minimize interfaces between GLV and TSV inside the pack

● Fastener and Part Standardization ● Rapid Cell Replacement ● Sophisticated State of Charge (SoC) algorithm

○ Acquisition of vital cell parameters ○ Accurate Cell Model ○ Implementation of algorithm on MicroController

● Robust Charging Interconnect: Monserrat Mendez and Nick Steele -The primary design objectives of the ME Interconnect team are to design, manufacture and install an electrical enclosure for the Tractive System Interface (TSI), Grounded Low Voltage (GLV) and Motor Controller systems. Goals:

● Cable Test ● System Integration

○ Lights, buttons, dashboards, etc. ○ Strain Relief

● To complete panels with proper holes for connectors ● Fix the Relay Board


○ Have horizontal bus bars ○ New design for fuse holders

● Design proper shelving location and structure ○ Includes hinges and sliders

● Update isolation walls ○ Check for proper material in rules ○ Potentially measure the real one for guidance

● Include a Din rail mount to have the CAN BUS horizontal instead of vertical to allow for more space

● Update Lid ○ Make decisions on how lid will be opening ○ Potentially include holes for connectors

● Finish Final Design ● Get Approval ● Start working on drawings to get part manufactured if necessary

Chassis: Gabe Fagen and Austin Ray - The chassis is the heart of the Car. The chassis is the central part of the formula car that everything is bolted and attached to. Our biggest goal is to maintain a lightweight car that can withstand the downward forces that are produced as the vehicle moves. Goals:

● Widen cockpit to be rules compliant ○ cutout top two side impact frame members and weld in bent ones, giving 1-inch of

extra space on each side ● Mount seat to give driver comfort and ease of access to controls ● Design and install side and rear firewalls ● Design and weld mountings onto chassis for other systems ● Confirm impact attenuator testing

Drivetrain: Luc D’Andrea and Michael Rittmaster - The drivetrain is the part of the formula car that supplies the torque from the motor to the wheels. In our car that consists of the motor, motor mount, chain, sprockets, differential, and half shafts. Goals:

● Install rule compliant fasteners ● Develop a fully functional cooling system for the motor and motor controller ● Develop a waterproof housing for motor cables that also achieves strain relief ● Design and manufacture appropriate guarding for the motor, wiring, chain drive, and

sprocket ● Test all parts built last year to make sure they meet rules compliance as well as if they are

as efficient as possible ● Install half shafts and hubs ● Redesign differential adapter to create shelf for sprocket, and add helicoils to remove the

need for fasteners (Fasteners cause clearance issues) Steering: Zach Miller


Steering’s primary requirement is to implement a secure steering system that prevents bump steer. This will include an enclosure that prevents on-track debris from clogging the steering rack gear system. Last year’s team purchased and attached a steering rack to the car and this will be used. Goals:

● Steering rack enclosure. ● Aligned steering rack.

Pedals: Dan Becker

The overall requirement of the pedals is to provide the driver with control over the throttle and brakes. Each pedal must be designed and manufactured to fit within a designated area in the chassis that is easy to reach and allow for adequate control without straining for any driver. The pedal cluster will include a dead pedal, a brake pedal with dual-actuated master cylinders, and an accelerator pedal that sends signals to the motor controller. Goals:

● New pedal design for brake and accelerator ● Better positioning and ergonomics for driver control and comfort

The Project Managers have constructed a list of six major team goals and objectives for the

Lafayette College SAE Formula Hybrid Team Members and Management to follow to promote the highest level of success. These goals and objectives will be further utilized to quantify the respective measurements of success, communication and team effort. The quantification is measured both individually and project wide. Weekly individual progress reports (IPR) and combined weekly project status letters (PSL) help to quantify the whole teams current standing, each subsystems current progress, and show where each individual team member is at per his or her respective responsibilities.

Individual Progress Reports are due each Sunday night to both project managers, and all three professors. From there the two Project Managers, Cat and Jordyn create the weekly Project Status Letter report that is displayed and talked through in the combined mechanical and electrical meeting on Monday afternoons. The following list is the list of team goals and objectives:

Goal One: Plan and manage an engineering design project:

Creating a plan of how to manage an engineering design project, allows you to be incontrol of the project instead of the project being in control of you. The project plan won’t spell out every exact thing that might happen, but it will explain the large majority of tasks that need to be completed, as well as provide detail to bring the team to the competition.

Goal Two: Demonstrate an understanding of the fundamentals of teamwork in terms of leadership, team orientation, mutual performance monitoring, backup behavior, and adaptability:

Establishing roles and responsibility is another key to success. Understanding and gaining agreement on project objectives and deliverables, will ensure the project team, system engineers, and project management team agree on the work that is required.

Goal Three: Demonstrate strong technical communication skills:


Communications skills forces individuals to interact with project team members, decision makers, as well as other stakeholders. The improvement of communication skills will help this team, and is the key to success for this project.

Goal Four: Solve engineering problems and create engineering designs:

Solving engineering problems is not a step by step process. In fact, there truthfully is not process. In order to solve an engineering problem and create engineering designs, each member of a team must think about each of the important component that makes up the end goal of the project. Each player on the team must utilize and play to his or her strengths individually. Then as a team all these ideas combine and mesh together to create possible solutions to the engineering design.

Goal Five: Create a test plan based on a solid understanding of measurement and quality assurance methodology:

A testing plan was created in order to turn these written project goals and objectives into a reality. Goals and objectives require set and stone dates, or deadlines. From a scheduling and milestone perspective, dates will create a solid understanding of completing tasks on time in order to make deadlines. The Project Management Team believes deadlines will be a crucial part to keep the project on schedule.

Goal Six: Engage in professional and responsible behavior during project work and demonstrate the capacity to grow professionally:

These attributes allow our team to work as efficiently as possible. Task priorities can be assigned and the allocation of resources during project execution can be conducted smoothly.

If a team proposes a change, which is approved by Managers and Advisors in the Monday Meeting it will be told to all affected parties by Spoken Word and Email in order to record it officially and Slack (This team’s Professional Messaging Software) in the case someone is unavailable

5. TEAM SCHEDULE Our team’s defined timeline consists of internal and external deliverables. Major internal

deliverables are displayed in a defined timeline as communicated in figure 8. Major external deliverables are communicated through the gantt chart in figure 9.

The Gantt Chart displays the defined timeline pertaining to common deliverables, mechanical department deliverables, and required documents for submission. The Gantt Chart also touches on the the biggest milestones for the project. The major milestones are, a Rolling Chassis by December 3rd, 2019, and an Electrical Completion date of March 10th, 2020.

Major Internal deliverables consist of what our team is calling “Major Mechanical Milestones”. These milestones were derived from the major mechanical subsystems: chassis, drivetrain, suspension, pedals, interconnect, and the battery team.

The goals for internal and external deliverables are being measured and tracked through the implementation of deadlines, staying on schedule, and communicating to team members via the work breakdown structure master schedule what percentage of completion a subsystem has completed based on progress.


Identified milestones in the planned approach are measured through the Master Schedule that Project Managers designed and created. This master schedule is linked to this sentence for the readers' convenience. The Master Schedule is a running excel document that consists of 12 sheets, one for each subsystem. Here each team documents the WBS items approaching and completed WBS items. This schedule serves as the heart of the Lafayette Motorsports team. All 25 members have access and permission to update the document, which further allows each subsystem to check the current progress of other subsystems throughout the week. The team only meets every Monday as a combined Mechanical and ELectrical team for updates. The Master Schedule allows the project to move efficiently, and most importantly, allows ALL subsystems to collaborate daily.

Figure 8: Internal Deliverables: Major Mechanical Milestones


https://docs.google.com/spreadsheets/d/1jTbJSEOK42Zik44ZGAFbmcpAqO9qfD0oQuuK2kQU0SQ/edit#gid=1983588496

Figure 9: External Deliverables


6. REQUIRED RESOURCES

Numerous resources are necessary and are required to achieve the team’s goal of creating an improved competition-ready electric car. While many tools and parts are readily available to our team, many must be ordered or designed. This situation works to the team's advantage, as it allows us to design custom made parts. Furthermore, the team is excited to use the resources available to us by working closely with the Mechanical Engineering Department, specifically Serena, to order parts and materials from the necessary suppliers.

This team of Mechanical Engineers is quite knowledgeable in programs such as ANSYS, Autodesk Inventor, and AutoCAD, which are useful for aspects of the mechanical design of the car. Many team members have already become close with the Machine Shop Technicians, specifically Rob, and are receiving the proper training for welding, machining, and are in the process of or have become certified in the stated specializations, along with other tools. This team considers itself lucky for having the presence of Shop Technicians who are extremely experienced and who provide constructive criticism.

Physical assembling of the car is conducted on the first floor of Acopian Engineering Center, across from the Machine Shop; this pertains to the Mechanical Engineers on the project. Electrical Engineers, respectively, conduct more of their work on the 4th floor of Acopian Engineering Center.

As the car is an electrical system that makes use of high voltages and is potentially dangerous, insulated tools are used to work on the car to minimize risk. Multimeters are available to take measurements of voltage, current, and resistance throughout parts of the car as needed.

It is imperative that our team to have access to a trailer in order to transport the car to and from Metzgar. Our goal is to begin testing a month before our March competition.

6.1. Operating Budget The Motorsport team’s overall budget is broken down by subsystem, which can be

referenced in Figure 10. The figure displays each respective sub-system, with its corresponding allocated budget, the total amount of the budget spent, the budget that is remaining, and the percentage of the budget that has been spent. The team’s overall proposed budget is $28,290.00. Registration in itself is $2,300.00. The shipping estimate is close to $3,700.00, this is because last years the team rushed shipped an extensive amount of parts, so this team is ensuring all possibilities. Our team is currently in touch with many companies in order to figure out lead times for necessary parts needed in the future. TSV also has a hefty budget of $8,000.00. Keep in mind the TSV subsystem is a combined electrical and mechanical subsystem. Much of what the budget comes from is the use of the insulation material, garolite, which is a strong, machinable, and electrically insulating material. On top of this, the subsystem must also produce a full prototype, as well as TWO final systems.

Figure 11 displays the percentage of the team’s total budget that has been spent up to the week of October 21st, 2019. Figure 12 displays a breakdown of each subsystem in a bar graph corresponding to the percent spent on each team’s respective allocated budget.


Sub-System Allocated Budget Total Spent Budget Remaining Percentage Spent

Pedal/Controls $200.00 $0.00 $200.00 0.00%

Cooling $200.00 $152.40 $47.60 76.20%

Brakes $400.00 $0.00 $400.00 0.00%

SCADA $800.00 $218.87 $581.13 27.36%

Dyno $100.00 $0.00 $100.00 0.00%

Suspension $2,500.00 $845.70 $1,654.30 33.83%

Steering $200.00 $0.00 $200.00 0.00%

Carman $4,400.00 $1,018.75 $3,381.25 23.15%

Shipping $3,690.00 $130.51 $3,559.49 3.54%

Interconnect $700.00 $0.00 $700.00 0.00%

Registration $2,300.00 $2,300.00 $0.00 100.00%

Drive Train $3,500.00 $12.92 $3,487.08 0.37%

TSV $8,000.00 $209.60 $7,790.40 2.62%

Chassis/Body $1,300.00 $0.00 $1,300.00 0.00%

Overall $28,290.00 $4,888.75 $23,401.25 17.28%

Figure 10: Overall Budget

Figure 11: Overall vs. Ideal Percentage Spent of Total Budget


Figure 12: Percentage of Allocated Budget Spent

7. STAKEHOLDERS OR EXTERNAL PARTNERSHIPS

Throughout the design process the team will consult a variety of individuals for advice and assistance to realize success in the March competition. Perhaps some of the most important of these individuals are those with prior FSAE experience, including Lafayette College professors and alumni. The team already has established channels of communication with both these groups of individuals and have already used them to seek advice during initial design stages.

Professor Helm (Mechanical Engineering Department), Professor Sajadian (Electrical and Computer Engineering Department) and Professor Nadovich (Electrical and Computer Engineering Department) will be consulted for advice throughout the entirety of the project, especially relating to questions about adhering to the rules, designing for effectiveness, and performing for success during competition. In addition, other Lafayette Professors have been, and will continue to be, consulted for their knowledge of specific engineering topics as well, such as heat transfer through the battery pack or aerodynamics of the completed chassis.

Along with Lafayette College professors, Lafayette College alumni will also be contacted using the team’s network to engineering students who have graduated in years prior. Lafayette College’s FSAE team of 2019 has been and will continue to be contacted for resources from the previous year and questions about design decisions, as the current team is further developing the car they have designed. The 2018 team has also been contacted and will be utilized more as spring approaches, as they are the last team from Lafayette College with experience from the FSAE competition.


Using this network of partnerships, the team will be supported by experienced advisors with robust backgrounds in electrical and mechanical engineering as well as the FSAE competition. In this way, the Lafayette College FSAE Team of 2020 will be supported in every step of design and performance in competition to ensure success come spring

8. RISK AND HAZARD IDENTIFICATION MANAGEMENT

Our team project is structured around large machinery and circuit boards. Both of these items are extremely dangerous and come in many forms that the team may utilize. The utilization of these tools are the reason specific risks and hazards have been addressed and identified in order to ensure a safe completion of the project.

In terms of risk management the chosen processes that have been chosen most concerning are the Accumulator Management System, the Accumulator Pack, and any TSV and GLV non-complete isolation. .

Accumulator Management System consists of a battery/accumulator management system is essential to the accumulators as specified in the rules, our plan to create three new boards is going to be exceptionally difficult to complete. Although TSV is the largest team, it will still be a challenge to finish this in time for competition. A mitigation plan for the AMS has already been set and we have multiple members of the team looking for commercial BMS systems just in case the AMS is not finished.

The issues of the Accumulator Packs is how mechanically driven they are. Without a container, regardless of if the AMS is working and the cells provide voltage, we cannot go to the competition. There are many rules involving the manufacturing of the packs so this is a large task for only two mechanical engineers. A mitigation plan for this is to get on top of it as soon as possible. If the two people working on the mechanical portion of the packs are not making enough progress, management will need to move people from suspension and drivetrain to help design and manufacture these packs. This could be after the rolling chassis is completed, or even before if that is possible.

Any TSV and GLV non-complete isolation is also of concern. As of now the team intends on creating one enclosure for TSI and GLV and because there is GLV present inside the accumulator containers as well, there could be a lack of complete isolation in either of these systems. If it is not completely isolated the team will not be allowed on the track. In order to fix this during design, isolation of GLV and TSV subsystems is always of utmost priority. Every stage of the design process should include a test for isolation.

The TSV-specific accumulator is the housing responsible for the insulation of all high voltage systems. In order to make this enclosure safe electrically safe, the team must obey all 2020 rules regarding insulation and isolation of both high and low voltage systems. To make the accumulator mechanically safe, the team must verify that the enclosure can withstand 20G vertically and 40G horizontally. This ensures that nothing in the accumulator will come loose, and that the enclosure will not remove itself from its mounts.

There are 4 major safety concerns that the chassis team needs to consider. The first of these is the ability of the frame, especially the front and main roll hoops, to keep the driver protected in the event of a crash and possible roll. Proper material is needed to make the frame of the car, 0.17” thick steel tubes were used for this frame. The roll hoops also have to be sufficiently above any body part of the driver, notably the head, to protect the driver if the car rolls. The next major


concern is the impact attenuator’s success in absorbing most of the force in a front collision. Sufficient impact attenuator testing has to be done in order to ensure the attenuator’s successful performance. Third, the side and rear firewalls need to properly protect the driver from subsystems that could get to a hazardous temperature, namely the battery packs and motor. 1/16” thick aluminum plates are being used as protection. Lastly, the driver needs to be properly secured into the racing seat, and be able to exit the cockpit in under 5 seconds. A rules compliant harness with attachment points on the chassis frame is being used, and the seat is being positioned where getting in and out is possible in a timely manner.

Suspension’s primary safety concerns are: preventing bump-steer, ensuring that the various suspension components will be able to sustain the design metrics provided by the FSAE electric competition, ensuring that the driver is safe at all times, and welding safety. Preventing bump steer is accomplished by modeling the suspension system and ensuring that there is proper give in the shock absorbers, such that bumps are absorbed. As part of our tech inspection, we will have to prove that our vehicle can undergo various tilt and g-force tests. This can be completed by performing finite element analysis on our full scale model. As the car is required to hold a significant angle of 60 degrees without rolling, significant modeling will need to be done to prepare for this. Driver safety is always our foremost concern when designing the vehicle. As suspension can contain many moving parts, from the steering rack under their legs to the attachments of the wheels to the car, it is important that we undergo a significant safety analysis of the suspension and its subsystems before the vehicle can be considered completed.

8.1. Risk Assessment Matrix

A risk assessment seeks to identify hazards, processes, and situations that create harmful situations for team members. The Motorsports team has chosen to create a risk assessment matrix plan on the welding process. Welding is a significant aspect to the assembly aspect of the vehicle.

Welding is the process of permanently joining two or more materials together. Gas flames, electric arcs, electric resistance, lasers, beams, friction, and more. The risk management process 4

involves identifying hazards, assessing risks, and controlling risks Figure 13 is the Lafayette College Mechanical Engineering Risk Assessment Form that displays the Risk Level Matrix.

The breakdown has been broken down to Figure 14. The chosen hazards are flammable substances, exposed skin, not wearing a helmet, and welding on a wet floor. Our team is required to go through an intense certification process if a teammate plans on using any tool during the duration of the project.

4 https://www.brighthubengineering.com/manufacturing-technology/30578-types-of-welding-processes/


https://www.brighthubengineering.com/manufacturing-technology/30578-types-of-welding-processes/

Figure 13: Lafayette College Mechanical Engineering Risk Assessment Form


WELDING RISK ASSESSMENT MATRIX

Hazard Event Controls in Place Impact Likelihood Risk Level

Flammable substance

Fire no flammable substances in place, no paper, ect

extremely bright flash

5 High

Exposed skin

Skin Burn Injury

welder must be equipped with personal protection equipment

contact with hot welded pieces

3 High

not wearing a helmet

Inhalation welder must be equipped with personal protection equipment

welding fumes

2 Moderate

Exposed skin

Radiation welder must be wearing a coat, goggles, and helmets

extremely bright flash

3 High

Welding on a wet floor

Electrical welder must be equipped with personal protection equipment

electrocution 5 High

\ Figure 14: Welding Risk Assessment Matrix

CONCLUSION

The Lafayette College 2019-2020 SAE Formula Hybrid Team is in the initial design stages

of developing an electric formula car to participate in the Spring 2020 competition. The major goals of the team is to develop a competition rules compliant car through the following critical points: 1) complete the rolling chassis by December 3, 2019, begin system testing by February 7, 2020, and take part in the 2020 FSAE competition on March 10th, 2020.

The team will be engineering the formula car by dividing itself into eight subsystems. These subsystems consist of: suspension, drivetrain, chassis, steering/pedals, battery, interconnect, SCADA, and grounded low voltage. While members of each subsystem will be responsible for the development of the majority of each subsystem’s electronics/mechanics, there will be a large amount of coordination between subsystems to ensure the team’s success (i.e. both the chassis and the battery team will work together to create the firewall to cover the batteries and mounting that will attach the batteries to the chassis itself).

The chassis subsystem will be focused on modifying the chassis design from previous years and fabricating the firewalls and mountings for other subsystems. The suspension team will


be working to manufacture A-arms, pushrods, and several other parts to ensure the rolling chassis will be finished by the December deadline. The drivetrain subsystem is focused on finalizing the motor, motor mount, differential, chain, and half shafts by making subtle modifications to last year’s design. The interconnect subsystem’s main concerns include creating enclosures, mountings, and connections between the Tractive System Interface (TSI), Grounded Low Voltage (GLV) and motor controller systems by working with the GLV and SCADA teams. The battery (TSV) subsystem is working on a complete battery redesign to develop two battery packs that will power the formula car with high voltage. The steering/pedal subsystem will be focused on finalizing the human control of the formula car.

The 2019-2020 team will be led by the following leadership structure: Faculty Advisor - Professor Helm, System Engineers - Nick Steele and Dan Becker, Project Manager - Cat Neely, Financial Officer - Monserrat Mendez, and Inventory Officer - Zach Miller. Utilizing this leadership, as well as the network of other Lafayette College professors and FSAE team alumni, the 2019-2020 SAE Formula Hybrid Team will ensure success at the 2020 March competition.


SAE Formula Hybrid Team Mechanical Design Review (MDR) Report › motorsports › files › 2020 ›...

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