oric_dan:
You mean he should add a large capacitor directly on the power supply right ?
When you say "single-point", you mean same ground or common reference, correct ?Not quite. It's all shown in the references I gave.
a. the capacitor goes right at the point where the battery connects to the system, meaning at the "+" below. With the capacitor there, it compensates for the inductance in the battery-wires, and removes the inductive voltage transient.
battery - battery_wires --- + --- controller
b. "single-point" means the ground wires, and power leads for that matter, from all of the subsystems [eg, battery, logic controller, motor controller] are brought to a single-point. So the wiring looks like a "star", or I prefer, an octopus. No ground loops. This way the current distributed to each subsystem goes through its own set of wires, and never goes through the wires of the other subsystems.
Also, adding item 4 to the three above, in general with electronics there is no magic bullet. IE, no one "fix" may cause all the problems to go away. Electronics is really always a systems-level problem, and everything has to be done properly. The first thing is always to get rid of the spaghetti wiring lashup, and do it right. This helps reduce noise, ground loops, cross-talk, signal radiation, on and on.
a: understood XD XD
b:That's what is called common ground reference, when all grounds end up to the same point ..