ABSTRACT Efficycle SAE-INDIA is an intercollegiate competition organized by SAE-INDIA on national level. The competition is organized to design, analyze, fabricate (manufacture) and race an energy efficient, low cost, eco-friendly, two passenger hybrid (human powered + electric) tricycles.Vehicle performance depends on acceleration, maneuverability and Gradeability, so performance can be enriched by keeping low weight, better gear ratios, high transmission efficiency and accurate C.G. of vehicle. A balance must be found between strength and weight of roll cage to ensure safety of drivers.All the limiting parameters are decided by SAE and design of vehicle is optimized in compliance with the guidelines set by EFFICYCYCLE 2012 Rulebook. Initially a prototype model of roll cage was designed in 3D model with the use of software like CATIA V5R19, ANSYS 10.0, COSMOS (Solid Works). Then after analyzing roll cage in ANSYS 10.0 by generating static and dynamic conditions (Roll over impact, Side impact) we modified design of roll cage with some improvements.To study the effects of stress and deformation on the frame members, linear static analysis was carried out by using FEA techniques for different loading conditions on the roll cage model in Solid Works simulation and ANSYS 10.0. The roll cage design also presents the techniques involved in fabrication of roll cage such as SMAW and aligned processes. To validate the chosen welding technique we have also performed process failure mode and effect analysis.Power train is designed by taking considerations of many practical conditions like aerodynamic, weather, road tracks, and dynamic resistances. Then suitable range of gear ratios is decided by taking care of availability in market. Other departments like brakes, steering, and suspension have been focused simultaneously while designing roll cage and power train.The project also focuses on ergonomic considerations, cost reduction, carbon footprint, problems faced during manufacturing etc. Our project also contents design validation plan, marketing strategies, expected market survey and owners manual. Keywords: - Rollcage, powertrain, steering, suspension, ergonomicsChapter 1 INTRODUCTION

1.1 Background

Efficycle SAE-INDIA is an intercollegiate competition organized on national level for undergraduate engineering students.The objective of competition is to design and manufacture an energy efficient eco friendly tricycle. This competition helps students to face real world engineering problems in design and manufacturing of automobile.Categories on which vehicle is judged are as follows: 1. Knowledge of rulebook 2. Project Plan 3. Extent of completion of vehicle design 4. Design Methodology 5. Materials Used 6. Compliance with rulebook 7. Finite Element Analysis 8. Safety 9. Innovation 10. Design Validation Plan

All the teams are required to follow the rules set by Efficycle 2012 rulebook, vehicle must be driven by two passengers (drivers) manually and simultaneously or alternately by electric drive system having motor driven by dry batteries.Low manual efforts and larger life of batteries (Endurance) are an important concern in the design of vehicle. So vehicle is designed by splitting it in following departments.1. Power train2. Roll cage3. Ergonomics4. Steering & Suspension5. Brakes & Wheels

1.2 Problem Definition

When two drivers seat together the total weight including vehicle increases tremendously so main task is to design low weight vehicle so that it can be driven smoothly, reliably and comfortably. Ride with less effort must be achieved by designing proper power train, brakes, steering and suspension. Problems in safety and comfort can be tackled by optimum size of roll cage and ergonomic considerations.

1.3 Objectives

The purpose of designing and manufacturing a Efficycle vehicle was to create a prototype of an energy efficient hybrid human powered three wheeled electric vehicle, that could provide safe, reliable and comfortable ride experience to the driver. We began the task of designing by conducting extensive research of each main component of the Efficycle vehicle, different design aspects of Efficycle vehicle were analyzed, and certain elements of the bicycle were chosen for specific focus. There are many facts to an efficycle vehicle, such as the Roll cage, suspension, steering, power-train, and braking, all of which require thorough design concentration. The vehicle should be aerodynamic, highly engineered and ergonomically designed. The design must be commercially viable as a product and is attractive to the consumers because of its visual appearance, performance, reliability and ease of operation. For designing we should choose inside out approach i.e. keeping manikin as reference and building entire structure around it so that it helps to design the vehicle as a whole and optimality of each component was maintained. As many components are interrelated we have to redesign components along the way in order to have a successful design. With consumer interest as the primary focus we used innovative methods and established techniques such as FMEA and benchmarking in our design process. We have succeeded in developing a vehicle with great performance, excellent driver ergonomics and efficient manufacturability. Technical report portrays the design methodology and analysis used to design and manufacture the vehicle.The vehicle must have: 1. Low efforts requirement 2. Safety provided3. Ergonomically good4. Smoothly operating 5. Low weight6. Compliance with rulebook 7. Safe design

Chapter 2 Power Train 2.1 Rules of Efficycle 2012 Power train Rulebook 400 watt motor PMDC or BLDC only No use of hub motor Only dry batteries Power input can be given to rear or front wheels No use of solar or any other source than electric battery

Any wheelAuto-transmissionMotorDry battery

Any wheelAutomotive Transmission Pedals

2.2 Internal and External factors affecting development of automotive transmission

Internal factorsExternal factors

Roll cageRoad profile

Battery (electrical & electronic)Driving style

MotorPay load

Automotive transmissionWeather conditions

Note: Manual and electric power can be used simultaneously or alternately.As maximum power of motor is 400 watt tricycle comes in parallel hybrid passenger car type. Power can be used to move vehicle in a motion on a road which is resisted by many resisted forces like 1. Aerodynamic resistance2. Rolling resistance3. Gradient resistance4. Inertial resistance

Power = Force X Velocity = Torque X Angular velocity = Torque X 2 n

Vehicle need a range of torques and velocities for different situations i.e. grades / slopes & road conditions. So it is necessary to use different gear ratios.Gear Ratio = 1/2 = n1/n2 = z2/z1 where z2z1Gear ratio is defined as a relationship between output speed and input speed hence gear ratio affects on both speed and torque.Power = Traction effort X VelocityMicro hybrid Mild hybridFull hybrid

Power of electric motor2-10 KW4-20 KW>20 KW

Torque of electric motor