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DEVELOPMENT OF A BICYCLE ROLLER BENCH PROTOTYPE

Bruno Miguel Caeiro Urbano bruno.urbano@tecnico.ulisboa.pt

Instituto Superior Técnico, Universidade de Lisboa, Portugal November 2016

ABSTRACT The present work aims at the modelation and structural analysis of a roller bench. SolidWorks 2015 is used as a CAD3D tool for modelation and structural analysis of the equipment. First, as an introduction, it is presented a bibliographic revision of cycling sport and a brief review of structural analysis, focusing the finite element method (FEM) and CAD3D softwares. Next, as an equipment’s background, will be discussed three equipment’s types and a few patents, where the main advantages and disadvantages of each type of equipment will be discussed. After that, the main requirements and objectives for the roller bench will be discussed followed by the core of this work: modelation of the equipment and a structural analysis. In order to obtain a model that satisfies the defined requirements, several models will be performed using the CAD3D program SolidWorks 20015. Next, after the modelation phase is completed, it is performed a structural analysis. First the critical components of the structure will be selected based on its function and expected behaviour to the applied load. A finite element analysis (FEA) will be performed to this components, and a shear analysis will be applied to one of the components. For the components provided by a company, it is performed a catalogue enquiry, in order to evaluate its structural stability. Afterwards, the construction of the prototype will be developed, and a cost analysis will be performed, in order to take the conclusions regarding the investment done and the money saved. In addition, a few functional tests will be performed, in order to get feedback about this project. Finally the conclusions of the work done will be presented and a few suggestions of future work will also be proposed. Keywords: Bicycle roller bench, structural analysis, finite element method, prototype

1. INTRODUCTION Since the early days of mankind that man feels the need to move around and to perform certain activities to survive. Due to the human civilization development and the concern about the improvement of movement speed and effort reduction, the activities have developed into an entertainment nature. Compared with some species of the animal kingdom, the human body has a lower efficiency performing long distances, having lower velocities and higher muscular effort. The bicycle invention allowed to improve the lack of efficiency, and, consequently, to travel longer distances with a lower effort. Nowadays, professional cycling is taken as a main choice sport, being considered one of the most stringent [1]. The difference between loose or win could be just a fraction of a second, thereby training is essencial to increase the athletes’ performance[2]. There is a demand for indoor training, with the development of new cycle-ergonomic equipment, which approximately simulates the real cycling without the unpredictable outside conditions [3]. In order to achieve a better performance, a research around cycling equipment is being developed, using laboratories equipped with turbo trainers and cycle-ergonomics equipment [2].

Currently, CAD (Computer Aided Design) and CAE (Computer Aided Engineering) softwares are getting more users, which allow users to design products in a 3D perspective and to analyze structural parameters as stress, displacement and natural frequencies. SolidWorks is a CAD/CAE software, which allows to design a product and to analyze it using add-in SolidWorks Simulation. This software uses a Finite Element Method (FEM), and the results are listed resorting to graphics and animations [4] [5]. From a theoretical perspective, the main objective of a structural analysis is to calculate deformations and internal forces and stresses. In a practical way, the structural analysis reveals the performance of a product under predefined conditions, ensuring its structural stability, without directly test the product [4]. FEM is a numerical method that aims to calculate approximate solutions of partial differential equations (PDE), in which there is a domain division of the problem into small parts, defined as finite elements (FE’s). This method is one of the most usual methods to perform structural simulations in Mechanical Engineering. The practical application of this method is called Finite Element Analysis (FEA). The main objectives of this thesis consist in the modelation of a bicycle roller bench and its structural analysis resorting to SolidWorks 2015, and the construction of a prototype of the roller bench

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designed. To construct the prototype is expected to use easy access materials and at low prices.

2. EQUIPMENT BACKGROUND The development of physical capacities through training is an essential part to achieve success in the competitions [6]. Due to indoor cycling equipment’s evolution, the athletes could increase their own performance, without leaving home, or in specialized centers for that. The main advantages of indoor cycling equipment’s are:

§ Perform and evaluate the physical condition when the outside conditions don’t allow;

§ Train at any time in a controlled environment, without any concerns about outside incidents, weather conditions or late hours;

§ Recover from sport injuries, in a controlled environment, reducing the risks associated.

On the other hand, the main disadvantage of those equipment is the fact that not all of them can simulate precisely the outside cycling. The indoor training devices are mainly divided in 3 models, namely:

§ Static bicycle; § Turbo trainers; § Roller trainer.

The indoor training devices differ from each other in what respects to the noise produced, occupied area, structural design and outside cycling simulation precision. 2.1. Static Bicycle Static bicycle, also known as ergonomic bicycle or maintenance bicycle is characterized by a rigid and compact structure, being similar to a bicycle but without wheels, Figure 1.

(a)

(b)

Figure 1: Two models of static bicycles; (a) DOONE BA

and (b) DOONE ICZERO

The main features of the static bicycles are time, velocity and distance measurement. The price for this type of indoor equipment varies approximately from Eur 100 to Eur 2,500 for specialized devices with specific functions. 2.2. Turbo Trainers As with static bicycle, the cycling movement with a turbo trainer is also static. However, turbo trainers (Figure 2) allow the user to use its own bicycle. Those are mainly composed by main frame, usually of alloy, a clamp system to support the back wheel and a brake system, which allow users to feel different resistance intensity when pedaling.

(a)

(b)

(c)

(d)

Figure 2: Turbo trainer; (a) Magnetic, (b) Fluid, (c) Wind and (d) Electromagnetic.

The most used resistance system are: magnetic system, fluid system, win system and electromagnetic resistance system. According to the power curve of each resistance type, they are more or less expensive. Nowadays, electromagnetic turbo trainers are the most used, although they are the most expensive, with a price range from Eur 300 to Eur 2,000, approximately. 2.3. Roller trainer Roller trainers (Figure 3) are indoor equipment which have larger dimensions than the other two models. Composed by a main horizontal frame with three rollers (two for the back wheel and one for the front). The front roller and one of the back are connected by a belt, in order to transmit the rotation velocity from the back wheel to the front wheel.

Figure 3: Roller trainer "Minoura Live Roll 700"

The design structure of these indoor training equipment have been used to develop bicycle roller benches, which finality is to measure the power produced. A lot of roller benches have been developed. At the beginning they had some lacks in their structure, not allowing the natural swinging movement of the bicycle [7] [8]. This is largely due to the fact that the bicycle was fixed in the structure to prevent falls.

(a)

(b)

Figure 4: Two developed patents;[7] [8]

Some patents have been developed, allowing the swinging movement of the bicycle. The transmission belt that creates together with the free structure a

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gyroscope effect, represents an essential feature. This allows the stability of the bicycle without being fixed. However, some authors add bumpers laterally, in each roller, to prevent the bicycle from escaping [9]. Motors/generators were added to the structures to measure the power produced and to control the intensity of the resistance force applied.

3. ROLLER BENCH OBJECTIVES AND REQUIREMENTS

In this work it is intended to develop a roller bench structure that allows the users to perform their cycling capabilities indoor, simulating as much as possible the outdoor cycling. For that, the structure should be able to support the efforts applied, having a good structural resistance. At last, it is intended to design an user friendly equipment, easy to transport and to store, without forgetting the overall costs. To achieve the objectives, the structure should comply with the following requirements:

§ Allow measuring the power produced, by adding a motor/generator;

§ Allow an easy setup of the rollers gaps, allowing the usage of different bicycle sizes;

§ Composed by cheap and easy access materials like steel and alloy.

In order to allow the usage of different bicycle sizes, it is first defined the gap between the rollers. In order to define this gap, a research about the correct way to lay the wheels on the rollers. As a result, it was defined a 300 millimeters gap between the back rollers and a gap of 1275 millimeters between the front roller and the back roller (Figure 5). The front wheels axle should be tangent to the back surface of the front roller. The back wheel should lay centered on the back rollers, as showed, but not too much, in order not to increase the difficulty of the usage.

Figure 5: Defined dimensions for the rollers gap

In addition, to add a motor/generator and to measure the power, it is first needed to estimate the power that could be generated. A research around this was also performed and that results in a rated power between 150 Watts and 300 Watts, and a peak power between 1000 Watts and 2378 Watts [10]. To verify these values, it was estimated the power generated by a cyclist. Therefore, the power P in Watts [W] is calculated in equation (3.1) by the product between the resistive force - Fresistive and the velocity in meters per second [m/s] – v.

resistiveP F v= × (3.1) The Fresistive is calculated by the sum of rolling resistance force – Frolling, gravity force – Fgravity and aerodynamic resistance – Faerodynamic.

resistive rolling gravity aeroF F F F= + + (3.2) Faero, Frolling and Fgravity are calculated in the equations (3.3), (3.4) and (3.5) respectively. The air density is ρ=1,22Kg/m3, the projected frontal area is A=0,5m2, the drag coefficient is Cd= 1.15, the rolling resistance coefficient is Crr=0,007, m is the mass of a person equal to 100Kg, g is the gravitational acceleration (g=9.81m/s2) and α the slope in degrees [º].

212aeroF A Cd vρ= × × × × (3.3)

rolling rrF C m g= × × (3.4)

singravityF m g α= × × (3.5) From solving equation(3.1), with α =0 in equation(3.5), is obtained P=1975,85 Watts. This value is considered as a peak power. To calculate the rated power it was considered that there are not aerodynamic resistance, because there are not relative movement. Thus, as a result of that, is obtained P=95,38 Watts, confirming the values obtained before. From that results, it is known that the motor should have a peak power above the one obtained.

4. ROLLER BENCH DESIGN In order to achieve a structure that best suits and comply with the set requirements, three structures were designed. All the parts were designed in SolidWorks 2015, since it was considered one of the most productive [11]. The first design developed (Figure 6) was discarded due to a weak structural rigidity, resulting from the fact that the tube beams needed to be cut to let the rollers have a free movement on a caster inside the beams. Other reasons to disregard this solution were concerning about the complexity of producing some parts and the impossibility to control the distance between the back rollers and the front roller.

Figure 6: First design developed in SolidWorks 2015

The second design developed (Figure 7) was also discarded. With this solution, the problems faced in the

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first one were solved. To solve the low stiffness problem, the tube beams were changed into “T” profile beams and the base of the caster became rails. However, it has some problems as well. The “T” profile beams are not economically viable and were needed a lot of parts to perform the caster system. Also, the roller subassembly had some lacks, being hard to construct.

Figure 7: Second design developed in SolidWorks 2015

To solve the problems above identified, a third and final design were developed. The roller bench structure, which was intended to be similar to a roller trainer, was split in four subassemblies:

§ Rails subassembly (lateral front and back rails and top and bottom rails);

§ Beams subassembly (front and back beams subassemblies);

§ Roller subassembly (roller, roller ends and house bearings);

§ Motor subassembly (motor and motor support). The first subassembly (rails subassembly, Figure

8a) is composed by: § 2 rails of three different lengths ( 550mm,680,

and 1250mm) with a rectangular section of 30x28x2 [mm];

§ 8 PLA bumpers inside of the rails to block the beams movement;

§ 4 PLA “L” profile joints; § 4 middle joint sheets.

and the components are all connected with M5 socket head screws.

(a)

(b)

(c)

Figure 8: Final design: (a) rails subassembly, (b) zoom-in

corner joint and (c) zoom-in middle joint.

The next subassembly is the beams subassembly (Figure 9a). This is constituted by 4 subassemblies of 3 beams connected by M5 and M6 screws. Each subassembly of 3 beams are also composed by:

§ 2 bearing to allow the bars to move on the caster;

§ 4 transfer bearing to align the assembly on the rails, preventing friction between this and the rail.

(a)

(b)

(c)

Figure 9: Final design: (a) beams subassembly, (b) front beams subassembly and (c) back beams subassembly.

At the top of each subassembly, there are holes to fix the house bearings with M6 screws, at different positions. The back positions are fixed and fully defined. The front positions are changeable with gaps of 25 millimeters, in order to allow the usage of different bicycle sizes. The third subassembly is the roller subassembly (Figure 10a), which is formed by 2 house bearings (Figure 10c) and 2 roller ends and 1 tube (roller) (Figure 10b).

(a)

(b)

(c)

Figure 10: Final design: (a) roller subassembly, (b) tube

and roller ends and (c) house bearing

The last one is the motor subassembly (Figure 11a), which is made up of the motor and its support (Figure 11b).

(a)

(b)

Figure 11: Final design: (a) motor subassembly and (b)

support.

Finally, connecting all the subassemblies presented, it is achieved the final assembly depicted in Figure 12a at is use position, and folded in Figure 12b to store it.

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(a)

(b)

Figure 12: Final design: (a) equipment at use position and

(b) equipment at folded position

The main opened and folded dimensions [mm] of the structure with the motor, as well as its own total mass [Kg] are described in Table 1. Table 1: Main dimensions [mm] and total mass [Kg] of the

final design.

Open Fold Length 1942,50 mm 1285,00 mm

Width 821,50 mm 821,50 mm

Height 190,00 mm 190,00 mm

Total Mass 15,78 Kg

In Figure 13 is represented the mass distribution of the structure per part type.

Figure 13: Distribution of the mass in percentage, per part

type

5. STRUCTURAL ANALYSIS After came up with a structure design that fulfills the requirements, a structural analysis is needed, in order to predict the structure behavior, when applied efforts. First, the main critical components or subassemblies of the structure are defined, in order to evaluate the structure stiffness, with no need to analyze the all structure. So, the roller subassembly, the motor support and the roller bearings and its axles are expected to be the most critical components of the

structure, because are the ones that will feel the bigger efforts. Next, the load distribution is analyzed. An experimental measure of the loads is conducted to verify the theoretical values. After, are developed a static analysis to the roller assembly and to the motor support, and a modal analysis to the support. Also, a shear analysis based on Mechanics of Materials is applied to the roller bearings axels. The suppliers catalogs were consulted for the bearing house units and the roller bearing, 5.1. Load distribution In percentage, in a starting position, the distribution load on the front and back wheel is 30% and 70%, respectively [12]. The same authors also refer that for a sprint position the distribution is 40% and 60%, and in a climbing position is 45% and 55%, respectively. In order to comprove the values above, an experimental measurement was developed. A person of 70 Kg, with a bicycle of 15 Kg, was lay above two balances, in the three positions described. The results obtained, in percentage, are presented in Table 2.

Table 2: Load distribution on bicycle wheels in starting position, sprint position and climbing position; a) front

wheel and b) back wheel

a)

33,5% b)

68,2 a)

40% b)

61,8% a)

45,3% b)

55,9% The most severe position to the structure is the climbing position, due to the back wheel lays on two rollers and the front wheel on just one roller. So, knowing that the maximum average value for the human weigh is 80,7 Kg [13], and for a bicycle, the maximum weight encountered was 17 Kg, the intensity of the total force applied in the static analysis to the roller subassembly was:

max. 0,45(80,7 17) 9,81 0,45431,4N

rollerF m g= × × == + × × ==

(5.1)

5.2. Static Analysis The static analysis was divided into 3 phases: pre-processing, processing and post-processing. In pre-processing phase were selected de parts to analyze and its materials, the connections, the fixtures and the external loads. Next, in processing phase, the mesh is applied and in post processing phase the results are obtained and discussed. For the roller subassembly analysis, the connections were set default and as fixtures, was applied a bearing fixture at the rollers ends. Then two external load situations were tried. On the first one, the load is

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centered (at middle of the roller) and on the second one is decentered. The mesh applied has been optimized until reached one with good properties. The mesh applied in the analysis has the following details (Table 3).

Table 3: Details of the mesh applied to roller assembly

Mesh Parts Roller Roller ends

Width 2.5mm 1mm

Nº of nodes 981676

Max aspect ratio 14.965

% Element with Aspect ratio < 3 98.5%

% Element with Aspect ratio > 10 0.162% 0.000609%

Execution time[s] 58 s 394 s

The results obtained for the first load situation are presented in Figure 14, Figure 15 and Figure 16, and in Figure 17, Figure 18 and Figure 19 for the second one. In the centered load situation, the maximum von Mises Stress was 164,1MPa, at the roller. The maximum displacement was about 4,7x10-1mm also at the roller, and the minimum safety factor was 2,1.

Figure 14: Stress distribution graphic of centered static

analysis to the roller subassembly

Figure 15: Displacement distribution graphic of centered

static analysis to the roller subassembly

Figure 16: Safety factor distribution graphic of centered

static analysis to the roller subassembly

For the decentered load situation, the maximum von Mises Stress was 161,8 MPa at the load application point. The maximum displacement was about 4,3x10-

1 mm at the same location, and a minimum safety factor of 1,8 at the roller ends.

Figure 17: Stress distribution graphic of decentered static

analysis to the roller subassembly

Figure 18: Displacement distribution graphic of decentered

static analysis to the roller subassembly

Figure 19: Safety factor distribution graphic of decentered

static analysis to the roller subassembly

For the motor support static analysis was applied the same method. First, the parts and its materials were

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defined. The connections were left by default and to fixtures was applied a fixed fixture at the bottom surface of the support. A mesh with good details (Table 4) was applied, after being optimized. Table 4: Details of the mesh applied to motor support

Mesh Parts Motor Support

Width 1.5 mm

Nº of nodes 232982

Max aspect ratio 10.143

% Element with Aspect ratio < 3 99.9%

% Element with Aspect ratio > 10 0.000702%

Execution time[s] 19 s

From the analysis were obtained the graphics depicted in Figure 20, Figure 21 and Figure 22, where the load corresponds to the motor weight. The maximum von Mises Stress obtained was 41,5MPa, the maximum displacement 3x10-1 mm and the safety factor was 4,2.

Figure 20: Stress distribution graphic of static analysis to

the support

Figure 21: Displacement distribution graphic of static

analysis to the support

Figure 22: Safety factor distribution graphic of static

analysis to the support

5.3. Modal Analysis For the modal analysis, the same parameters as static analysis were applied, in both pre-processing and processing phases. From this analysis was obtained the first five natural frequencies. These are presented in Figure 23.

Figure 23: First five natural frequencies obtained in modal

analysis to the motor support

The frequency of the pedaling have to be always smaller than the motor maximum working frequency. If the obtained frequencies are all greater than the motor maximum, so the analyzed component will not be in a resonance situation. 5.4. Other analysis A shear analysis was performed to analyze the bearings axles.

(a)

(b)

Figure 24: Roller bearings axles

The average shear stress is calculated by the equation(5.2),

cmed

PA

τ = (5.2)

where Po is the shear force applied and Ao (equation(5.3)) the cross section of the axle, presented in Figure 24.

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2 2 23,5 38,5A r mmπ π= = × ≈ (5.3) The maximum shear force is obtained on the back roller bearings and is calculated by the equation ().

. 0,7958,5 0,7 37 707,95total traseira total motorF F F

N= × + =

= × + = (5.4)

. 1774

total traseirac eixo

FP F N= = ≈ (5.5)

From that the results 4,6med MPaτ ≈ and the yield stress for the material used (AISI 1010 Steel, hot rolled bar) is 180 MPa, almost forty times bigger than the average shear stress. To validate de bearing house units and the roller bearings used, it was consulted the suppliers catalogs. For the bearing house units, the catalog [14] defines a 12.8KN for dynamic load and 6.65KN to static load. However, the bearing house units are just supporting a load of 215,7N (half of the maximum load on a roller), validate the security of these components. The bearings, by consulting the NTN Americas catalog [15] for ABEC-5 608-ZZ bearings, could support approximately 3400N on radial load and 1430N as static load. They are supporting a static load of 170N (the eight part of the total force applied to the structure), validating the structural stiffness.

6. PROTOTYPE CONSTRUCTION After the design of the equipment and its structural validation are completed, the next stage is the construction of the structure prototype. A costs analysis are also performed to compare the costs to construct the prototype with the amount that should be spent if the prototype had to be built in a specific company. The first step was to define the construction path depicted in Figure 25.

Figure 25: Prototype construction path

All the manufacturing processes were taken at DEM (Mechanical Engineering Department) LTO, helped by the persons responsible. The main manufacturing processes used were: 1 http://www.novoportugal.com/jose-maria-aluminios-lda/

§ Drilling; § Milling; § 3D Printing; § Bending; § Turning; § Cutting.

From Table 5 to Table 8 are presented the manufacturing processes applied and parts manufactured. The rails, as well as the beams and middle sheet joints, were donated by the company José Maria - Alumínios1 Lda. The six bearing house units, as well as the two belts and one pulley were gently donated by DUNBELT2 company. The PLA parts (corner joints and bumpers) were 3D printed in an Ultimaker 2 3D printer available on DEM. In Figure 26 is presented the roller bench prototype completed.

Table 5: Construction of rails subassembly parts

Parts Manufacturing Processes

Rails 1-Drilling 2-Finishing

Bumpers and Corner Joints 1-3D Printing

Middle Sheet Joints No processes applied

-Were acquired already manufactured

Table 6: Construction of roller subassemblies parts

Parts Manufacturing Processes Roller 1-Turning

No picture available

Roller Ends No processes applied

- Were acquired already

machined

Bearing House Units No processes applied

- Donated by DUNBELT

2 http://dunbelt.com/

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Table 7: Construction of beams assemblies’ parts

Parts Manufacturing Processes

Beams 1-Milling 2-Lateral beams drilling

3-Top beams

drilling 4-Finishing

Bearing Axels 1-Turning 2-Cutting

Bearings and

Transfer Bearings

No processes applied

- acquired on internet

Table 8: Construction of motor subassembly parts

Parts Manufacturing Processes Support 1-Drilling 2-Cutting

3-Bending 4-Finishing

Motor No processes applied

- Provided by supervisor

Belts No processes applied

-Belts donated by DUNBELT

Figure 26: Bicycle roller bench prototype.

In order to perform the cost analysis, the equipment was split in 3 groups:

§ Production resources; § Processed components;

§ Unprocessed components. To calculate the total amount that should be spent, was added the costs of the 3 groups (equation(6.1)).

( ) ( ) ( )T i ii iiiC C C C= + + (6.1)

where: ( )iC is the money spent buying the production

resources; ( )iiC is calculated doing the sum of the manufacturing processes costs and the raw material costs of all of the processed components (it was necessary to know the labour costs – CHH and machine costs – CHM in euros per hour [€/h]); ( )iiiC is the sum of the sales costs of each component of this group. Resorting to an Excel spreadsheet, those costs were calculated and as a result from that, the graphics depicted in Figure 27 and Figure 28 were obtained. As could be seen in Figure 28, the amount spent (144,24€) are about a quarter of the amount that should spent (total costs on dark blue, 601,82€). So, is possible to conclude that the easy access and cheaper material requirement was fulfilled.

Figure 27: Distribution costs per group

Figure 28: Total costs analysis; Dark blue: money that

should be spent to construct the equipment in a specific company

7. FUNCTIONAL TESTS To analyze if the prototype is working correctly, and to check if it is in accordance with the main requirements, a set of simple tests were developed. Firstly, the usage of the equipment was evaluated. For that a user uses the equipment normally, paying attention to the security of it, the difficulty felt and the response of the structure to an unexpected acceleration. The feedback of the user was positive: the prototype is relatively safe, allowing an unexpected variation of speed, although it is a bit hard to pedal.

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The second test was set to analyze if the motor was measuring correctly the power produced. That one was not possible to develop until this time. The third test aimed to obtain the time needed to change the position of the front roller, evaluating the difficulty of this action. As expected, a slight number of operations are required to change the position of the front roller, taking about 3 minutes to conclude the task. The last test conducted was to check the difficulty of transporting and storing the equipment. As expected, the structure, due to its relatively large dimensions, is slightly difficult to transport by just one person. Although, to store, it doesn’t require much space.

8. CONCLUSIONS The work presented addresses the prototype development of a bicycle roller bench structure. It consisted in three main phases: (i) design phase, (ii) structural validation phase and (iii) prototype construction phase. From phase (i) where the structure was designed, the three designs realized, allowed to come up with a viable structure, which fulfills the main requirements imposed. The 3D CAD program used, SolidWorks 2015, help a lot to achieve a good design, most due to its user-friendliness and its available features. On the second phase of the present work, structural validation phases, were applied several structural analysis to the roller subassembly and to the motor subassembly. The practical experience conducted to verify the load distribution ends with the expected results, in order to verify the researched values. To perform the static and modal analysis was also used the SolidWorks 2015, which was very helpful to verify the stiffness of the structure. From the structural analysis applied to the roller subassembly, it was possible to conclude that, in the first case, where the load was centered, the structure is well sized and it supports the defined efforts, presenting a safety factor of 2.1. When the load was decentered, the safety factor decreases to 1.8, but nonetheless the FS obtained is close to 2, considering the structure structurally valid. The modal analysis performed showed that the structure, and mainly the motor support, will not vibrate at the same frequency of the pedaling of the person, ensuring its correct functionality. The last of three main phases was the prototype construction phase, which allowed to obtain practical and theoretical knowledge about the material used and also about the manufacturing processes applied. In conclusion, the work developed achieved the main objective, which was to develop a bicycle roller bench prototype. For future applications, is first suggested to perform a new anchoring system for the bearing house units, in order to be possible to apply more tension on belts, and the development of a better and more useful energy dissipating system. Secondly, the

instrumentation of the equipment with sensors and a controller for the resistance force provided by de motor are also suggested.

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