There are three power switches and circuit breakers mounted. One is for power to the laptop recharger; one is for power to the microcontroller and sensor electronics; and one is for power to the motors. All of these are mounted at the top back of the frame for ease of reach (like when the robot is running amuck).
In theory, only the motor power switch is critical as it will shut down everything the robot actually DOES that might cause damage. In fact, if I ever find a nice big red override switch, I'll probably mount it on top of the robot in series with this switch.
The switches are standard automotive switches available at any auto parts store. The circuit breakers are my favorites, but you can use anything or even fuses. I've spend a lot of years putting in circuit breakers rather than fuses, and I only recall a circuit breaker popping once.
I also mounted a terminal strip below the switches for ease of wiring. I found it at a surplus outlet. Try to get something big enough to handle multiple wires in the future.
Actual wiring is shown here
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