This report details the considerations and processes behind our all-terrain vehicle. INTRODUCTION EFFI-CYCLE 2012 is an intercollegiate design competition for undergraduate students which are aimed at designing and fabricating an energy efficient hybrid human powered three? wheeled electric vehicle. It provides us an opportunity by setting up a trend of using eco? friendly vehicles in India and come up with some innovative designs. We, GREEN RHINOS, consists of 8 undergraduate 3rd year students from Mechanical and Production department of Government College of Technology, Tamil Nadu.
The team was keen on utilizing the platform to learn, innovate and implement. The following paper outlines the design and analysis of the Efficycle 2012 Green Rhinos three wheeled vehicle. DESIGN METHODOLOGY: The designing of the vehicle has been carried after studying the various designs of the fore-mentioned trikes, followed by its advantages and disadvantages. All the design issues were studied and an attempt has been made tosolve them in the present design. Then, the design is subjected to various load conditions at the sides and front with finite element analysis using ANSYS.
It was also made sure that the components used where readily available so that without a major modification, we can use it in the manufacturing process. SOFTWARE USED: ?Designing and Assembly of the vehicle:Solidworks-2012 ?Roll cage analysis: ANSYS TECHNICAL SPECIFICATIONS: ?Frame: IS1239 MS 1 inch rod ?Welding type: MIG ?Bending: Mechanical type bending ?Brake: Hub brake and Rim brake ?Steering: Rack and Pinion ?Motor: 0. 5 HP , 24V PMDC ?Battery: 12V, 35 am-hr ?Suspension: Spring-arm suspension type ?Drive train: Sprockets and chain ?Controller unit: PWM unit ?Tyres: Cycle tyre 28 inch diameter?
SALIENT FEATURES ?Individual suspension system to the front two wheels. ?Rack and pinion steering system. ?IS1239 MS frame ?Seating position enabling complete view to both drivers. DESIGN SYSTEM The design section is classified as follows: 1. Roll cage design and analysis 2. Drivetrain 3. Steering 4. Suspension 5. Tires 6. Brakes 7. Wheel Assembly 8. Aerodynamics ROLL CAGE DESIGN: ?Roll Cage Model Using Solidworks: Roll cage provides three dimensional stability and safety to the drivers. The roll cage was designed with utmost care to reduce the weight without compromising the safety of driver.
The rules for designing the roll cage were carefully revived and the design was made in such a way that each and every member falls within the rules. The material for the rollcage is chosen as IS1239 mild-steel after considering various materials in terms of material strength, its availability and cost. Table showing the list of various available materials: MATERIALYIELD STRENGTH (KSI)MODULUS OF ELASTICITY (KSI)COST PER METER (RS) AISI 101853. 729700600 AISI 102042. 7297002200 IS 123959. 1229700150 AISI 413065. 1297002500 Of all the available materials, the chosen one is IS 1239 MS pipe because of its weight and cost.
It weighs around 0. 8 kg per m. Moreover, we had chosen seamless tube manufactured by drawing process, owing to its high strength rather than the pipe manufactured by rolling process. ?Roll cage analysis using ANSYS: Roll cagewas analyzed in the ANSYS software. Cage was analyzed at each and every stage and the extra members were provided in order to reduce the stress concentration. The roll cage is initially meshed and the nodes are found. Final design is tested at 2000N in case of front and side impact which is very sufficient to ensure safety. The cage also passed all other tests and had a good factor of safety.
The stress diagrams are given below. Analysis Results: Type of TestForce appliedResult Front impact2000Passed Side impact2000. Passed Roll over2000Passed DRIVETRAIN: The drive transmission is facilitated with the help of chains and sprockets. It is a rear wheel drive vehicle. The transmission is alternatively or simultaneously driven by motor or manual pedaling. Manual drive type: The drive train plays a major key role in every vehicle. In our vehicle, we had used the pedaling system found in boats which is simply attached to the frame with the help of bearings on both sides.
At the centre of the crank, a sprocket of 48 teeth had been fitted which is directly connected to the left freewheel, (where threading is done manually) of the rear tyre, providing a simple transmission system as found in ordinary cycles. Electrical drive type: The simpler the electrical drive is, the simpler the manufacturing process goes on. A 0. 5 hp motor mounted under the right side of the seat is connected to the right freewheel of the rear tyre. It is connected with the help of cycles chains and sprockets. Three reduction has been given to the motor.
Under the left seat, four 12 v 35 am-hr batteries has mounted and connected in series to provide power to the motor. Further, a PWM circuit controller mode has been installed to the system, so that a efficient way of control is provided with the least losses. STEERING SYSTEM: The main objectives of the steering system are to provide the driver with an accurate, predictable, and reliable method for navigating a vehicle over rough terrain. A small turning radius provides the driver with a responsive and controllable ride. The rack and pinion system is a proven method of steering that is direct and reliable.
In addition, the steering system does not interfere with the suspension, allowing for optimal negotiation of off-road conditions. SUPENSION Suspension is the term given to the system of springs, shock absorbers and linkages that connects a vehicle to its wheels. It is the critical part of an automobile which absorbs shocks and vibrations and gives smooth ride. It also control the force transmitted by sprung and unsprung mass. Therefore it becomes important to have very good design of suspension system based on non-linear parameters and design variables. As concerned with our three wheeled vehicle, a spring arm suspension system has been used.
Spring arm type shock absorbers are so easily available and has good shock absorbing characterisitics. It is connected directly to the wheels and the frame, providing a jerk-less driving. TYRES: Selecting the tires is one of the most important things as the whole vehicle is in contact with the road on these points. Tyres provide the required traction for the vehicle. We had chosen ordinary three-wheeler tyres and made a modifications over the tyres replacing the central hub of the wheel. Front and back tires Diameter28 inches Width2 inches HUB: BRAKES: Brakes are the frictional devices used to retard the motion of the vehicle.
It converts the kinetic energy of the vehicle into heat energy. According to the EFFICYCLE 2012 rules, all the wheels should be locked when braking is applied. While designing the brake system, simplicity was given prime importance and itwas decided to use hub brakes for the front two tyres that are attached over the hub assembly. Then for the rear wheel, rim brake has been given. SEATING ARRANGEMENT: Two seats are arranged parallel aside one another so that the complete view of the roads are clearly visible to both the drivers. Seats have been so arranged so that it provides a good back support.
The seats are good designed and readily available in the market. AERODYNAMICS: The shape of the vehicle so designed is such that the aerodynamic mechanism would work better. Fairings had been added to enrich the look and style of the vehicle. ASSEMBLED VIEW OF OUR DESIGN: SUMMARIZED COST REPORT: S. NOSYSTEMCOST 1ROLL CAGE2800 2STEERING5800 3SUSPENSION1000 4DRIVE TRAIN20000 5WHEELS3500 6BRAKES800 7OTHERS2000 TOTAL37000 PROJECT PLAN: Sl noDateDescription 14-8-12 to 8-8-12 Discussion about the efficycle and analysing about the problems on the fabrication of our model and making plan and scheduling according to the problem.
29-8-12 To 16-8-12 Selection of the material 317-8-12 To 20-8-12Market research 527-8-12 To 4-9-12 Fabrication of Roll cage 65-9-12 To 10-9-12Steering, suspension and wheel work 711-9-12 To 20-9-12 Drive chain work 825-9-12 To 27-9-12 Electronic work on motor, battery and controller unit. CONCLUSION: Our cycle has been designed so that it meets all the needs of the consumers. The roll cage has been designed completely for the safety factor and it provides ultimated safety for the riders. Efficient braking system had been installed. Simple steering system.