POWER SUPPLY

The power supply section takes current from the main 12 volts battery and runs it through switches and circuit breakers before making it available to other components on the robot.

Features:

Battery attach leads may have a second set of connections so the battery can be switched with robot running.  Just attach new battery then remove dead battery.

30amp fuse for entire robot. Protects against shorts anywhere.

Individual circuit breakers on each circuit .  This permits use of lower gauge wire to individual circuits.

Laptop battery is continuously recharged extending robot's overall battery life.

General electronics modules usually have separate 5 vdc internal regulators powered from 8vdc robot bus.  The drawing shows provision for a 12 to 8 vdc high efficiency regulator.  This hasn't been implemented yet, the electronics modules generate their 5 vdc directly from the 12 vdc supply

"Motors" switch can be used for emergency shutdown without stopping computers.

"Laptop" switch can be turned off if primary battery is getting low.

 

Implementation:

The battery is mounted within the frame structure on top of the platform to help keep the center of gravity of the robot low and centered.

The power switches, circuit breakers and terminal strip are mounted high for ease of reach.

All power wiring is run up and down the left rear corner of the frame to keep power switching from contaminating other more sensitive signals.

For wire gauges,  I used #12 from the battery to the switches (which should handle up to 30 amps) and #18 from the switches through the circuit breakers to the user (which should be 10 or 15 amps max).  These gauge wires are available at auto parts stores.

 

Parts List:

Battery:   Helios 12 volt  17 ah with F1 terminal.    batteries.com   (including shipping)   $ 39.21
  (note: any other similar batteries will work)

Switches:   (3 of) automotive style   12 volt 30 amp (any auto part store)            approx $  8

Circuit breakers:   (3 of)   Electronics store.   find source???                              approx $ 12

Fuse:   (any auto parts store)                                                                               approx  $  3

Laptop charger:   laptopsforless.com has  DC chargers.
    I got
Item: DC-DC-DELLCP DC to DC adapter for Dell       (including shipping)        $59.30
    They seem to have chargers for many laptops. And relatively high efficiency.

                                                                                Total                    approx               $ 120.