Keeping to our design philosophy (simple, cheap, common), bicycle caliper brakes were used - 2 on rear wheels, 2 on front wheels. (If you can afford disk brakes, you are encouraged to use them. Please contribute your tested design to the forum here .) These front and rear brake sets are independent of each other with the rear brakes operated with a brake pedal between the foot pedals. The front brakes are operated with a handlebar-mounted brake lever. Both sets have mechanical connectors that equalize the force applied to left and right wheel by the lever or the pedal. This helps with straighter, more controlled braking. The following photos summarize:
This view is from under the chassis showing rear brake cabling.
The right front brake: