Project

Objective:

To carry out system level simulation for All terrain Vehicles of BAJA ATV with continuously varying transmission.

Model study:

We have a BAJA ATV with CVT Simulink model having different blocks and it is controlled by acceleration throttle and brake which are given as input.

The complete project has three windows, Dashboard model and display. The dashboard is used as input for the ATV Model which has Acceleration and Brake as input. Also it has Gauge meters which display velocity and RPM at particular point of time corresponding to inputs.

Simscape model has generic engine block which takes acceleration and brake as input.

A Generic engine converts fuel energy into mechanical energy and the output is read in the form of RPM using engine sensor and data is recorded. The Mechanical data is fed into CVT which has a primary and secondary shaft with varying gear ratio. The output is fed into simple gear box and into vehicle body which use the mechanical rotational energy for linear motion.

Continuously variable transmission (CVT):

CVT uses Variable Gear ratio block which calculates the secondary RPM. The input force taken from generic engine is transmitted into variable gear ratio which uses gear ratio provided from lookup table and based on inputs it calculates the output RPM for the secondary pulley.

Results and conclusion:

The BAJA ATV with CVT Simulink model was run for varying throttle and brake. The output data was recorded and as follows.

Throttle & Brake v/s Velocity v/s Distance

The above plot has details of throttle conditions as applied while simulation and corresponding behaviours of in velocity and overall distance travelled. Also the plot is use brake applied while simulation of model and we can observe the fall in velocity and slope for distance has reduced while braking and it indicates that the time taken for covering a distance has increased.

Primary RPM v/s Secondary RPM

The plot shows the variation of secondary RPM over primary RPM according to variable gear ratio.

Generic Engine RPM:

The plot is output RPM from engine block and we can observe the variation of engine output for the variation of throttle valve and brake.