I have a design in mind for a sampling device. I am wondering if it is possible to add an independently controlled 9th thruster to the heavy kit. The idea is to keep the controls for the ROV itself un touched but add an extra thruster that would just need forward and reverse controls to bring water in and out of a chamber.
How feasible is this? Is there provisions to control that many thrusters, or would I be better off going with standard configuration and utilizing the extra thruster capability from heavy kit?
It is simple to map the extra thruster to a servo output channel, and control its speed and direction with button presses from Cockpit or QGround Control. Fitting a 9th ESC in the enclosure is also possible, if a bit tricky. Using the heavy configuration will let the vehicle better resist the force the extra thruster imposes on the system when in use.
I found the room for the added ESC. I am wondering how you went about mapping the servo output to run the thruster? Are only certain aux outputs able to be used to control ESC. It looks like I have AUX 4 and 5 outputs available since I have so many other accessories. I was hoping to not have to remove anything but can if need be.
If a SERVOn_FUNCTION parameter is set to Disabled (0) then its corresponding output should be controllable directly
For a standard servo-style PWM signal you should be able to use any of the outputs, but AUX 1/2/3 (Servo 9/10/11 on Navigator) are marginally easier with the currently available firmware[1], because of the existing servo_n_* joystick button functions.
I am struggling with adding the extra thruster. Since the ROV was purchased a few years ago, I decided to update to Blue OS and will start using cockpit. I flashed a new micro SD with Blue OS. When attempting to communicate to the raspberry pi it seems very glitchy and I am having trouble. I then tried to put the old SD in, also with no luck talking to the ROV through IP. Any help would be appreciated.
The link light stays on while connected. When trying to access blueOS with IP address it often won’t connect at all. Occasionally it will for some reason decide to connect. When connected it seems like connection is very spotty and sometimes it is lost. I get anywhere from 10-50 notifications about timeout ms exceeded. For some reason mavlink camera is using 25-400% of CPU and jumps around a lot in terms of CPU usage. The cockpit icon pops up and goes away frequently as well.
I would be happy to go back to the old OS but I am having trouble figuring out how to get this additional thruster working.
I’ve tried putting the old sd card in and accessing the raspberry pi via IP address and it won’t connect. Though the ROV seems to function normally using ground control.
Hi @pantherrov -
The old SD card that uses companion would have its web interface reached at 192.168.2.2:2770 (need the port!)
It sounds like you have an issue with either your connection to the vehicle, or the autopilot itself. (pixhawk? this is an older model?)
To confirm, the link light is staying solid at all times, and never goes out when you have connection issues?
It may be worth flashing an SD card with the latest stable, version 1.4 just came out. This version is much better when it comes to handling the Pixhawk, and coping with the limited resources of the Pi 3.
Doing a network speed test in BlueOS once you have connection would be a good troubleshooting step! There is also the tether diagnostic extension that you could install and look “under the hood” of the Fathom-X tether interfaces used to send data along the 2 wires used in the tether.
I am now running the newest stable version of companion on the raspberry pi and firmware on the pixhawk. I have decided to stick with QGroundcontrol instead of using BlueOS, which I was eventually able to get working.
I’ve read through the links above in an attempt to map controller buttons to a 9th thruster. Since I am essentially computer illiterate, I was unable to make sense of the advice offered. I have the thruster power wired and the 2 pin connector connected to the AUX 4 port on the pixhawk.
I’d like to assign a button for forward and reverse for the added thruster. Could someone ELI5 how best to do this using Qgroundcontrol?
Hi @pantherrov -
AUX 4 on the pixhawk corresponds to Servo12. In QGroundControl, under vehicle setup, navigate to parameters and set Servo12 Function to “Lights2”.
You’ll then map the desired buttons in your joystick configuration to lights2 brighter/dimmer.
When the system boots, the lights signal will be at minimum (off) - and your extra thruster won’t initialize. You’ll need to increase the “lights2” brightness until the signal is 1500 microseconds - this may require playing with the lights2 steps so that 4 or 5 toggles reaches this value. When you hear the “beep” from the extra thruster, it has been initialized - increasing brightness will run the thruster in one direction, and decreasing it will run it in the other direction.
It’s a shame you’re not interested in updating to BlueOS - the newest 1.4 stable version works much better with older systems that still use Pixhawks than the previous stable…
I navigated to servo 12 function. “Lights2” is not an available option on the dropdown list. I’m not sure if this is related but when I navigate to the lights settings, I get a message about 1:BRD_PWM_count being missing. In an attempt to resolve the previous issues I updated the firmware on the pixhawk, updated groundcontrol and companion software. I’d be open to using BlueOS if it were to make this process any easier.
Hi @pantherrov -
Apologies for steering you wrong - I forgot that only BlueOS labels servo functions with human readable names. Lights2 should be set to RCIN10 for my instructions to work - the joystick button for lights2 will control that Aux4 output with that setting.
The 1:BRD_PWM_count error is just a nuisance, it is because QGround Control is not up to date with the parameters in newer ArduSub firmwares… Note that we don’t recommend using QGround Control newer than 4.2.8, especially with Companion…
BlueOS makes everything easier compared to the ancient Companion OS, imho!
Problem solved! It works like a charm. I appreciate your patience with my remedial skillset. I will eventually be swapping over to BlueOS, I just wanted to get this figured out and get operational again. Switching over may take me some time to set it up and get used to it.
