speedkar9

I tore down the entire braking system, from the brake pedal, booster master cylinder to the ABS actuator, calipers, computers and sensors to see what's inside and how it works:


Here's the entire braking system removed from the vehicle:



Here's what the brake booster looks like when chopped open. The key to its function is the valve in the middle, that activates when the pedal is depressed. This causes vacuum to assist one side, and atmospheric pressure to enter the back side of the diaphragm.



The master cylinder uses two pistons in series for redundancy:



The ABS actuator consists of an electric motor to help build brake pressure during a traction, stability or ABS event. There are 12 solenoids that determine fluid flow and pressure to the calipers.



The motor has an eccentric cam that pushes two pistons in the housing to generate pressure. Without it, the pedal would sink to the floor when ABS actuates.



This is the gyroscope that senses the vehicle is sliding sideways for the stability control system. It consists of a tiny MEM's device - a small mass on a silicon wafer. Its movement with the vehicle triggers a change in capacitance, which is detected by the ABS computer:



And finally here is the steering angle sensor. Two gears rotate with opposing outputs to encoders for redundancy:




Enjoy!

Toys4RJill

Wow. Great video. You have a great niche for you a You Tube snow. Very interesting dissection of the brake system.

Your ABS info was very informative. It still is quite astonishing that some people think ABS is a bad invention.

arentz07

This was really interesting to watch. There are a lot more parts going into ABS than I imagined!

speedkar9

Thanks, I'm glad you all learned from it. There sure is a lot more to an ABS system than just an ABS pump between the master cylinder and wheels. Modern vehicles integrate even more sensors, actuators and electronics into the car, to the point where the ABS module is responsible for braking the car in semi/autonomous mode.