2.4 Wiring

The constructor will by now have identified several problems with the wiring.

1. There is not enough of it for the robot to reach all positions comfortably
2. The extenders are prone to failure
3. There are not enough extenders
4. It is difficult to route the extender-connectors through the gaps in the mounting brackets
5. It is difficult to bundle all the wiring ideally
6. In order to prevent extensive wiring, it is necessary to loop some of it, which looks untidy if nothing else

A neater solution is to follow the automotive industry, and assemble all the wiring into a pre-fabricated loom before fitting to the robot. This requires some careful measurements and a little experimentation. However, the end result is neater, and probably more reliable (although it does suffer the disadvantage that, if something does go wrong, the whole lot will need to come off and be overhauled).

Note that we still keep the pin connectors to the control board, and that we install some close to each motor, but in a position that the connector is fastened securely to the robot’s framework.

A further gain to be made from creating a wiring loom is that we now only need a common ground and a common live; the signals still need to run separately from the control board to each motor, but as these do not carry much power they can be left thin (I wonder why the original motor wires are all the same gauge?)

We also notice that some of the motor wires are twisted, while others run flat like three-core ribbon cable. It is likely that in the intended application for these RC motors (radio-controlled model control) that the flat solution is ideal. However, for the robot we want to ensure that the wires will flex without prematurely breaking, and this is aided by the wires being twisted together. Hence this is how we construct our wiring loom.