Final answer:
The most common type of foundation brake found on heavy vehicles is the S-Cam brake, which works based on Pascal's principle and applies hydraulic pressure to the wheel brakes to create friction and stop the vehicle.
Step-by-step explanation:
The most common type of foundation brake found on heavy vehicles is the S-Cam brake.
The S-Cam brake system works based on Pascal's principle, which states that pressure exerted on a fluid is transmitted uniformly in all directions. In this brake system, when the driver pushes the brake pedal, it activates the master cylinder, which applies hydraulic pressure to the wheel brakes. The pressure is then transmitted through a series of linkages and cams to push the brake shoes against the brake drum, creating friction and stopping the vehicle.
Other types of foundation brakes, such as disc brakes and wedge brakes, are also used on heavy vehicles, but the S-Cam brake is the most common. In some heavy machinery like bulldozers, a motorized pump does most of the work, relieving operators from the need for significant physical force application.