Browse Publications Technical Papers 2018-01-1865
2018-10-05

Comparison of Different Variable Braking Force Systems 2018-01-1865

An automobile braking system has a crucial role in the safety of the passengers and riding quality of the vehicle. The braking force mainly depends on the normal reaction on the wheel and the coefficient of adhesion between the tire and the road surface. The required braking force for a vehicle varies with the load on the vehicle. If the applied brake force is greater than the required brake force, wheel gets locked which results in increased stopping distance. In order to prevent the wheel lock at low load conditions, a variable braking force system is developed. Whenever a motorcycle is loaded, the normal reaction on the rear wheel is increased. Thus, the amount of braking force required to halt the motorcycle with minimum stopping distance and stability of the motorcycle is based on the pillion load on the motorcycle. Hence, the amount of braking force developed between the road surface and the tire is varied in the variable braking force system. In this project, variable brake force system is achieved by varying the effective disc radius, pedal leverage and area of piston. Hence, the maximum brake force developed between the ground and the tire is controlled based on the pillion load on the motor cycle, if friction is present between the tire and the ground. Two calipers are mounted on the brake disc of which one is fixed at a constant distance (constant effective disc radius – 67mm) and the other is movable depending on the load on the motorcycle. The movable caliper slides upwards and downwards such that the effective disc radius is varied based on the pillion load. Using a load cell, the load of the vehicle is determined. A microcontroller is programmed to move the caliper with the help of a stepper motor based on the load on the motorcycle. This way, the effective disc radius is varied for various loads on the motorcycle. Predominantly, the results from simulation and estimation are compared between the three methods.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Attention: This item is not yet published. Pre-Order to be notified, via email, when it becomes available.