Project

Objective:

To prepare a technical report of the ATV model

All-Terrain Vehicle:

An ATV is also known as a quad bike, is a vehicle that travels in a low-pressure tire. This is used by a single operator.

CVT

A continuously variable transmission is an automatic transmission and it is a type of single-speed automatic gearbox that can change through a continuous change of gear ratios. The engine operates at a constant rpm while the vehicle moves at varying speeds.

Major Parts:

1)Generic engine: It represents a general internal combustion engine. Engine type includes spark engine and diesel engine.

B: Rotational conserving port representing the engine block

F: Rotational conserving port representing the engine crankshaft

T: Physical signal input port specifying the normal engine throttle level.

P: Physical signal output port reporting the instantaneous engine power

FC: Physical signal o/p port reporting the fuel consumption rate

The variable ratio transmission block

VRT block represents a gearbox that dynamically transfers motion and torque between the two connected driveshaft axes, base, and follower.VRT is a dynamic mechanism for transferring motion and torque between base and follower.

B and F are rotational conserving port

Variable gear ratio can be specified as a function of time at the physical signal input at port r.

Simple Gear: the simple gear blocks represent a gearbox that constrains the connected driveline axes of the base gear b and the follower gear f to corotate with the fixed ratio that you specify.

B indicates Base

F indicates Follower

Vehicle Body:

It represents a two-axle wheel body in a longitudinal motion. The vehicle can have the same or a different number of wheels on each axle.

W= Headwind speed,m/s

beta= road inclination angle ,rad

V=longitudinal velocity,m/s

NF=Front axle normal force, N

NR= Rear axle normal force, N

H =horizontal motion

Tire

A tire with longitudinal behavior is given by the magic formula, an empirical equation based on four fitting coefficients.

N=Normal force

M=Magic formula coefficients

S=Slip

A=Axle

H=Hub

Double shoe Brake

It represents a frictional brake with two pivoted rigid shoes that press against a rotating drum to produce a braking action. A positive actuating force causes the rigid shoes to press against the rotating drum.

F= Actuating force

S= Drum shaft rotation

H= Heat flow

CVT Gear Ratio

Torque speed Curve

Vehicle body

Case 1:

When the throttle is 1 after 30 sec and Brake is 0.

Vehicle speed increases gradually and after 30sec vehicle speed is 60km/hr.

CVT shaft rpm

Graph shows the variation between input and output shaft of the varaiable gear transmission system.

Case 2:

We have a dashboard in which we have knobs to control the throttle and brake.

It can be observed that the velocity of the vehicle increases drastically from 0 to 50kmph when the throttle value is 0.5& brake input is 0. Once the braking value increases from 0.1 to 0.5, the velocity of the vehicle decreases to 0 at a constant throttle value.

Part 2 With lookup table

i)Without dashboard

When the throttle is 0.5 for 20sec and after that when it is 1, the brake is 0, velocity increases after 20sec to 60km/hr.

ii) When the throttle is constant and the brake increased from 0 to 0.2 with a dashboard

Velocity decreases.

observation and conclusion :

1)When the brake is constant and when we increase the throttle velocity increases

2)When the throttle is constant and when we increase the brake value the velocity decreases.

3) The speed becomes constant after a certain rpm and decreases when the brakes are applied at different times.