Project
Aim: -
To detail study & analyse of BAJA-ALL Terrain vehicle (ATV) model using Simulink & run different condition.
Objectives: -
To carry out the Simulation of the BAJA All-Terrain vehicle (ATV) without using lookup table & with using lookup table study the technical report and explain in detail.
Explanation
BAJA All-Terrain vehicle (ATV): -
All-terrain vehicle (ATV) means a motorized off-highway vehicle designed to travel on four low-pressure or non-pneumatic tires, having a seat designed to be straddled by the operator & handlebars for steering control.
Fig (1): - ATV model
Components of a BAJA All-Terrain Vehicle (ATV): -
The main components used in BAJA-All Terrain Vehicle (ATV) are
-Vehicle Body
-Suspension
-Tire
-Engine
-Continuously Variable Transmission (CVT)
Part-A [1]
- Simulink model for BAJA All-Terrain vehicle (ATV) with Continuously Variable Transmission drive (CVT): -
Major components in the model:
Continuously Variable Transmission drive (CVT):
It is better to have more gears in transmission since it can optimize engine speed in a variety of driving conditions. That means low gears can provide better acceleration while higher gears can maximize fuel economy. CVTs differ from traditional automatic transmissions in that they don't have gears that provide "steps" between low- and high-speed operations. Instead, the majority of them work via a pair of variable diameters, cone-shaped pulleys connected by a steel or composite belt. The halves of each pulley are aligned with the pointed ends of the cones touching. These form a V-shaped groove in which the connecting belt rides. One side of the pulley is fixed, and the other side is movable, actuated by a hydraulic cylinder. The cylinder can increase or decrease the amount of space between the two sides of the pulley. This allows the belt to ride lower or higher along the walls of the pulley, depending on driving conditions. thereby changing the "gear" ratio.
CVT Block: -
Variable Transmission Ratio
Represents a variable ratio gearbox such as implemented by mechanical belt CVT. electric, or hydraulic transmissions. The physical signal input r defines the ratio of input to output angular shaft velocities.
Connections B (base) and F (follower) are mechanical rotational conserving ports. Specify the relation between base and follower rotation directions with the Output shaft rotates parameter.
ENGINE
Represents a system-level model of spark-ignition and diesel engines suitable for use at the initial stages of modelling when only the basic parameters are available. Optional idle speed and red line are included. The throttle input signal T lies between zero and one and specifies the torque demanded from the engine as a fraction of the maximum possible torque. Connections F and B are mechanical rotational conserving ports associated with the engine crankshaft and engine block. Connections P and FC are physical signal output ports through which engine power and fuel consumption rate are reported
INPUT SIGNAL
A signal builder is used to building the signal for brake and throttle
CVT Gear Ratio: -
Torque vs speed curve: -
In the above plot maximum velocity Reaches at 3840 RPM. Vehicle speed depend on CVT ratio.
Vehicle Body: -
Vehicle Speed
If we can see it is clear from the graph that if a vehicle attains its maximum speed (V=55km/hr) at full throttle 1 after =35 seconds and then remain constant the brake input value is zero hence it has no effect on velocity
CVT Shaft RPM
this graph shows the variation in the velocity in input and output shafts of the variable gear transmission system this value differs concerning the gear ratio.
Engine RPM
Part-A [2]
Simulink model for Baja AVT with CVT using Dashboard: -
We can see, in this model, we have a dashboard that contains knobs to control the inputs. In this case, the inputs- Throttle & Brake' are not provided using the signal builder. A knob is provided to control both the parameters in real-time for the user.
Result: -
Vehicle Speed
It can be observed from the graph that the velocity of the vehicle increases drastically from 0 to 50kmph when throttle value is 0.5 & brake input is O. Once the braking value increases from 0.1 to 0.5, the velocity of the vehicle decreases to O at constant throttle value. This explains the direct relation of vehicle velocity with respect to throttle and brake inputs.
CVT Shaft Speed
Part- B [1]
Simulink model for BAJA ATV with CTV using lookup Table: -
CVT Block
The only difference between this model and the first model is that in this model gear ratio input to CVT is provided using a lookup table. The vehicle velocity and vehicle rpm are the same as the first model
CVT Gear ratio
LOOKUP TABLE VISUALIZATION
Vehicle speed
CVT Shaft Speed
Input are same the result will be same.
Part: -B [2]
Simulink Model for BAJA ATV with CVT using Lookup Table & Dashboard: -
in the above model we the new thing is that this model provides us with the control brake input and throttle input
Result
Vehicle Speed
This graph is similar to the CVT dashboard case study the variation in vehicle velocity can be observed with the change in brake input and throttle input when we are increases the break input the speed of the vehicle is decrease on another case, we can see that when we increase the throttle input the vehicle velocity also increase.
CVT Shaft Speed
We can see this graph indicates the variation in rpm of primary and secondary shafts with respect to input parameters.
CONCLUSION:
System level simulation model BAJA-All Terrain Vehicle without using look up table is done & result are plot.
System level simulation model BAJA-All Terrain Vehicle with using look up table is done & result are plot.