ME460 Presentation

Automated Seeding Preliminary Design Review

Automated SeedingPreliminary Design ReviewTeam Members:Peter IshiguroShireen Kheradpey Jeremy LeeFrank Lin

Boston UniversityDepartment of Mechanical EngineeringDiscussion Leader: E. GutierrezLecturer: A. Sharon

OUTLINECustomer RequirementsFunctional DecompositionAlternative ConceptsFinal DesignInput SystemSeed Dispensing SystemOutput SystemFinancial JustificationBill of MaterialsCummulative Cash FlowUser interface screenAreas for Improvements

We will begin our presentation by talking about the different parameters and requirements we were given on how they influenced our design processThen we will break down and explain the details of our final design choiceAnd finish off with the expected financial impact of our automated seeding machine.

Customer RequirementsTransfer tray from input stack to seed dispensing systemTray Dimensions: 120 cm x 60 cm x 5 cmInput must accommodate stack of 10 trays

Fill each tray hole with one seed (95% accuracy)200 holes/tray (20 rows of 10 holes)Hole Diameter: 1 cm; Hole spacing: 5 cm 1 cmSeed Diameter: 0.1 cm

Stack seeded trays on output cartMinimum 5 cm overhead space for loaded cart

Cycle time = 90 sec per tray or less

To begin designing we first looked at our customer requirementsThe overall task was to take a tray from a stack of ten, fill each planter tray with a single seed in each hole, then stack the tray on an output cart with a cycle time no greater than 90s. The customer also included details such as the dimensions and geometry of the tray and size of each seed. An additional piece of information we acquired from the customer was that the output cart should have an ovrhead space of 5cm above each tray

Functional DecompositionAutomated Seeding MachineHold Tray Stack

Move Single Tray to ConveyorTransport Trays:1. Input to Dispenser2. Dispenser to OutputDispense seeds

Sense Finished TrayAdjust Tray Height

Fill Trays

Adjust Tray HeightTransfer Tray to Cart

JeremyFocus on tray input and output functions.

Morphological ChartParameterPossible Solutions

Tray Input / OutputLinear DriveScissors LiftClaw

TransportationLinear DriveConveyor BeltMove machinery to traysSeed DispenserVertical TubesAir SuctionRoller with Slots

Operator puts stack into placeInput system holds stack

PICTURES INSTEAD OF WORDSDispenserSensing-sense that tray is thereTransport to seed deispenser

Tray Input and OutputWeight FactorLinear Drive Scissors LiftClawSpeed100+1Cost10-1-1Weight Capacity20+1-1Stability20+1-1Ease of Assm10+1-1Controllability20-10TOTAL02-5

Seed Dispensing SubsystemWeight FactorVertical Feeder TubesAir SuctionRoller with SlotsReliability20+1+1Controllability20+1+1Cost10-10Ease of Assm.10-10TOTAL024

Jeremy

Preliminary Designs

JeremyPrelimiary;s

Final Design

Input SystemSeed DispensingOutput System

jEremy

Input: System Overview

Scissor Lift

Frank


Scissor Lift

Tray Stack

Frank


Scissor Lift

Pushing ArmTray Stack

Frank


Scissor Lift

Pushing ArmTray StackLimit Switch

Frank


Inverted Linear DriveScissor Lift

Pushing ArmTray StackLimit Switch

Frank

Input Mechanism

https://www.youtube.com/watch?v=xhqbGZws4ZI

Input: Machine Requirements

Load: 28.9 kgDistance Traveled: 1.2mMax Velocity = 0.3 m/sAcceleration = 0.075 m/s^2Time = 8 secTorque = 2.31 Nm

Event chart postition to position. Velocity profile chart --with velocity or timing values.Torque.Place numbers and calculations in the appendix.

Sensors at Input

Switch OpenSwitch ClosedCarriage

Switch closed by carriage returning to home positionClosing switch raises input stack by 5 cm

-Forward motion of push arm begins when signaled received from output lift

-Input lift raises a level upon push arm returning to retracted position

Dispensing System: Overview

Roller Seed Holes 1.5 mm, 1.5 mm deep4 equally spaced rows of 10 holes

PEte

Dispensing System: Overview (Cont.)

RollerBearingLimit SwitchStepper MotorTray Notches

Peter

Seed Dispensing System

https://www.youtube.com/watch?v=atwTzXtWwMg

Dispensing: Machine Requirements

max = 39.3 rev/s (2356 RPM)Time = 0.01 secTorque = 0.063 Nm

Seed Holes Row

= 90

same notes

Sensors at Dispenser-Gated sides of trays complete limit switch to power stepper motor

-Ensure seed dispense when holes in proper position.

Limit Switch OffLimit Switch On

1.7 cm gaps.circuit is completed when switch in gapTOP VIEWsnapshots: when in and switch is completed, when roller out

Output System: Overview

Scissor Lift

Linear Drive

Pushing Arm

Limit Switch

Brushless Motor

Jeremy

Output Mechanism

https://www.youtube.com/watch?v=jKHAuXazUN8

Output: Machine Requirements

Vmax = 0.3 m/sa = 0.15 m/s^2Time = 4 sTorque = 2.28 Nm

Load: 28.9 kgTravel Distance: 0.6m

position profilevelocity profileloadsTorque needed, motor choice

Sensors at OutputCompletion of tray loading onto output hit limit switch signaling:

-Input push arm to begin new cycle

-Lift adjusts height to correct level of cart

Open SwitchClosed Switch

Lifts Control

Powered by Hydraulic SystemProgrammed controller with height variation cycle

Courtesy of Presto Lifts

Timing DiagramRise input stack of trays

Push tray on to conveyor

Dispense individual row of seeds

Tray arrival at output lift

Lower / raise tray to cart levels

Conveyer Travel = 2.5sRaising = 1.5s(Occurs during previous cycle)Full Tray Dispensing = 19sTrigger: Gated tray side + Roller limit switch

Conveyer Travel = 11.8sTrigger: Return of push arm to retracted position + limit switchUnloading = 8sTrigger: Loading of output lift + limit switchLoading completion triggers limit switchMax travel = 6.3s Ave travel = 4.4sLoad tray on cartReturn to home positionLoading = 8sMax travel = 6.3s Ave travel = 4.4sAverage Cycle Time = 54.1s Programmed Controller

This timing diagram maps out the the one complete cycle of a tray, beginning at the input stack and ending on its respective level of the output cart. The average cycle time for a single tray with our machine would be 54.1 seconds. (54.1 for first tray and 41.3s for every tray after that)






Conveyer Travel = 2.5sRaising = 1.5s(Occurs during previous cycle)

Trigger: Return of push arm to retracted position + limit switchFull Tray Dispensing = 19sTrigger: Gated tray side + Roller limit switch

Conveyer Travel = 11.8sUnloading = 8sTrigger: Loading of output lift + limit switchLoading completion triggers limit switchMax travel = 6.3s Ave travel = 4.4sLoad tray on cartReturn to home positionLoading = 4sMax travel = 6.3s Ave travel = 4.4sAverage Cycle Time = 54.1s Programmed Controller

At the input, the raising of the tray to the level of the conveyor will be triggered by the pusharm returning to its contracted postition. This process will take 1.5s but because it occurs during the previous cycle, it does not contribute to the overall cycle time. After recieving a signal from the output system, the pusharm will proceed to transfer the tray on to the conveyor taking 8 seconds.








The tray will then travel for 2.5 seconds before it reaches the seed dispenser. The tray will then take 19 seconds to be completely loaded with seeds truggered by the gated stray side and the roller limit switch peter previouly spoke about.








After loading is completed the tray will travel for another 11.8 seconds as it is transferred off the conveyor onto the output lift. When the tray is fully loaded, it will his a limit switch which tells the pusharm to unload another tray at the input, and the limit switch also enables our programmed controller to take over.







Conveyer Travel = 11.8sTrigger: Return of push arm to retracted position + limit switchUnloading = 8sTrigger: Loading of output lift + limit switchLoading completion triggers limit switchLoad tray on cartReturn to home positionLoading = 8sMax total= 20.6 s Avg totall = 16..4sAverage Cycle Time = 54.1s Programmed Controller

The programmed controller tells the output lift what height to travel to, when the linear drive should unload the tray onto the cart. This will take a maximum of a6.6 seconds for the highest and lowest levels, or an average time of 12.8 seconds.

User Interface-Power On / Off-Emergency Shut off-Master Reset-Returns all lifts, push arms, etc to home position- Manual/Auto- Switch to manually control output scissor lift.

POWER

AUTOMANUAL

RESET

108945623

EMERGENCY SHUTOFF0)Home1)Level 12)Level 23)Level 34)Level 45)Level 56)Level 67)Level 77

ENTERCNCL

Our automated seed dispenser will also feature a user interface that includes a power on/off switch, and emergency shut off button, and a master reset button which will return all lifts to the height of the conveyour belt and the pusharm to its retracted position.

ComponentsCompanyPart NumberQtyUnit PriceTotal CostCart WheelsMisumiCLGK65-G4$98.52$394.08Linear Drive (1.2m stroke)ThomsonWM06S050-01200-01630AS-00001$3,077.00$3,077.00Linear Drive (0.6 m stroke)ThomsonWM06S050-00600-00990AS-00001$2,477.00$2,477.00Stepper MotorLin Engineering4018X-071$40.00$40.00DC Brushless MotorAerotechBM5001$1,195.40$1,195.40Scissors LiftPresto LiftDXS60-202$7,837.76$15,675.52ConveyorMisumiCVSX-500-2000-90-TA115-IM-75-H1$2,842.00$2,842.00Compact Limit SwitchMcMaster Carr7988K21$28.87$28.87Snap-Acting Limit SwitchMcMaster Carr7510T122$5.57$11.14Polyethylene Rod (3 ft)McMaster Carr8754K761$40.48$40.48Stainless Steel Sheet (100"x48")McMaster Carr8983K35815$606.31$9,094.65Stainless Steel Bar (1" Thick, 2' long)McMaster Carr8992K1672$78.91$157.82Stainless Steel Rod (d=3", l = 6ft)McMaster Carr89535K754$490.02$1,960.08Fasteners (Nuts, Bolts)McMaster CarrMultiple110$160$160.00Trough: 16875 in^3 SSMcMaster Carr8992K90831279.3$8,658.30Extraneous Costs Estimate--130000$30,000.00Total$78,202.34

Bill of Materials

Financial Justification: Bill of MaterialsTotal Development Cost = $462,200

4 Engineersworking at 40 hours/wkfor 6 monthsAssumptions made:2 months Preliminary Design2 months Final Design & Testing2 months Assembly & Integration

Extraneous Costs IncludeMilling cost for cart, trough, and input output stands

Financial JustificationDevelopment Cost: $462,200Annual Maintenance:$7,820Operation Costs:$50,000

Payback Time:1.48 yrsNPV (5yrs): $1.094MAnnual Tray Production:138,410Annual Savings: $319,094.27 0 1 2 3 4 5YearCummulative Cash Flow

calculating maintenance. ook at harsh environmentsconveyor = 6% of costbearing life for roller- good.estimating engineering hours = our own timeconstruction, software, testing validation, break it downtime of construction-

Concluding PointsImprovements to the system:

Trough ShakerPrevents seed cloggingTray CenteringAccount for disruptions along conveyor

Output Arm DesignAllow for flexibility of cart placement

Shireen

AcknowledgementsGutierrez, Advisor

Hauser

Sharon

Questions?

Appendix

Input & Output Motor Specifications

* Motors from Aerotech

Motor Sizing CalculationsTrayFF_frictionFBD:

ComponentMass (kg)Carriage0.36Pusher4.49Tray24.1Total28.95

INPUT (x = 1.2m, t = 8 sec) linear (Nm)2.30 rotary (Nm)0.01 min (Nm)2.31

OUTPUT (x = 0.6m t = 4 sec) linear (Nm)2.28 rotary (Nm)0.0015 min (Nm)2.28

Coefficient of friction steel on steel: 0.8

Dispenser Motor Specifications

*From Lin Engineering

Stepper Motor Sizing

Roller

()90Time (sec)0.01J motor (kgm^2)1.39E-04 min (Nm)0.063

Seeding Hole

Scissors Lift Specifications

Courtesy of Presto Lifts

Output Lift Program Pseudocode >Move lift to desired level>Hold lift position>Trigger linear drive>Return drive carriage to home>Lower lift level to home

Linear Drive Specifications

Input (Model No. WM06S050_01200):Stroke Length: 1.2 mLead: 50 mmScrew Diameter: 20 mmJ Screw: 0.0021 kgm^2

Output (Model No. WM06S050_00600):Stroke Length: 0.6 mLead: 50 mmScrew Diameter: 20 mmJ Screw: 0.0020 kgm^2

From Thomson Linear

Conveyor Specifications

From Misumi

Timing Diagram ExtrasFunctionTime (s)Raise Input tray0.5Transfer tray to conveyor8Dispense Seeds40Raise output lift6.3Transfer tray to cart4Max Cycle Time (1 Tray)58.8Cycle Time (10 Trays)561.5

Shelf No.Time(s)10 (Top)6.39583.872.56 (Start)051.342.533.8251 (Bottom)6.3

Raise Input CartTransfer to ConveyorDispense Seeds & Transfer to Lift

Raise Output Lift

Raise Output Lift

take away charts and below each steps do time, different slide to highlight step of interestwhat makes it start (trigger) -> next stepany important info can be placed underneath

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