Our robot has 8 Lumen Subsea Lights, 2 chains with 4 lights in each.
During the startup, all of them become 100% ON for a short period of rime. It causes voltage drops/spikes and other bad EMC stuff.
Is it possible to disable such a behavior somehow? Preferably in software.
I’ve already tried to find a software solution, but it looks like it is more related to the Pixhawk hardware. There is an old closed issue which describes a similar issue here:
Copter: pins high during boot causes problems for parachute release #1239
On my old original ROV, i wanted 5-dof manipulators and camera pan/ tilt, along with buoyancy/ ballast control, and LED light banks. Seeing the Pixhawk firmware wouldn’t allow me to control so many things, i had a guy write some code to make the Raspberry Pi control everything but the thrusters using an SSC32U servo controller connected to the Pi via I2C.
The Pixhawk acted as the autopilot and controlled the thrusters, while the Pi commanded the 32-pwm channel servo controller to tilt/ pan the camera, turn on lights, move the arms, drop ballast, etc.
On my new ROV, i intend to put a 4-port ethernet hub/ switch between the Pi and the Fathom X board, and connect in an 8-channel security system DVR so i can have up to 8 FPV microcams on the ROV, that i can view in Chromium on a separate monitor topside. Putting a microcam on each manipulator wrist will allow for much finer control when picking stuff up.
Sadly this is an hardware fault in the pixhawk during the bootloader and hardware configuration before ardupilot starts to run, it’s not possible to fix that without extra hardware.