Skid steering and power

Archive
1

Hi,

I’m currently working on a boat that will use ardupilot, with apm: rover as the brain.

My boat is a catamaran and I’m planning to use skid steering.

Connected the engines and speed controller for the first time yesterday, and it seems something didn’t quite work as intended.

Radio on, speed controllers on then power to ardupilot.

The left engine started immediately, full “left rudder” made it stop.
Right engine didn’t run at all.

In the standard params
I have two parameters that have something to do with skid: Skid steering input (SKID_STEER_IN) and Skid steering output (SKID_STEER_OUT), these two I have changed from disable to SkidSteeringInput and SkidSteeringOutput

Is there anything else I should be doing? The description says set this to 1, which I guess means SkidSteering*put

The speed controllers are MicroViper Marine10, these should have a BEC function

MicroViper Marine10 specification

[quote]10Amp motor limit
Motor short protection
Forwards & reverse
1.0KHz drive frequency
4.8V - 12.0V input voltage
1.2A BEC
Built in failsafe
26.0mm x 25.6mm x 9.0mm
100% Waterproof
Weight - 23.0g[/quote]

I removed the red wire from one of the speed controllers (per details in the instructions) so the ardupilot shouldn’t be powered from both, but i didn’t get any power on the ardupilot.
I had to run the power via usb, for the test that resulted in one engine running, the other standing still.

Do I have to use the power converterter from the package from 3ds to power the ardu pilot? My two motors draws ca 800mA so it is kind of overkill wires on it.

So, Any ideas for powering up the ardupilot and getting the engines to run as I want them to?

Thanks,

Carl

2

@cral79,
First off, SKID_STEER_IN should be 0 and SKID_STEER_OUT should be 1.
Next, are you using the Elevator joystick for the throttle input and the Aileron joystick for the steering input to the APM?
I do not recommend using the Throttle/Rudder joysticks for the throttle/steering inputs as you will have no reverse.
You can take the spring return off of the Elevator joystick so you will not have to physically hold the joystick in any particular throttle position to keep it from returning to neutral.
The APM left motor output should be on Servo Chnl 1 and the right motor output should be on Servo Chnl 3.
I do not recommend powering the APM through the Servo Output power bus with J1 installed. I would power the APM off of either the PM or a suitable BEC through the R/C input power bus: http://copter.ardupilot.com/wiki/common-apm25-and-26-overview/#Power_Supply_Rails_Not_Connected_Requirements_JP1_Not_Installed
Regards,
TCIII ArduRover2 Developer

3

Thanks for the quick reply.

Your first line, something wrong there?

As for the remote control setup, it is per recommendations from rover.ardupilot.com/wiki/setup/

Mode 2 controller, using the right stick for both forward and steering.

My controller is a futaba 7c if that has something to say.

This is my first build, so when you say
"Next, are you using the Elevator joystick for the throttle input and the Aileron joystick for the steering input to the APM?
I do not recommend using the Throttle/Rudder joysticks for the throttle/steering inputs as you will have no reverse.
You can take the spring return off of the Elevator joystick so you will not have to physically hold the joystick in any particular throttle position to keep it from returning to neutral."

Elevator? Aileron? I’m not sure how the setup is. I’ll try to use google to see what i find.

I presume engine trouble is because both are sat to skid_steer_* 1, and the power trouble is because I haven’t used the jumper to power things.

Regards

Carl

4

@cral79,
I corrected the first line in my previous post.

On a mode 2 transmitter, the right joystick has an Elevator joystick (up/down) for pitch control (throttle for a rover) and an Aileron joystick (right/left) for roll control (steering for a rover).

Regards,
TCIII ArduRover2 Developer

5

Thanks for helping :slight_smile:

But, I fear I’m a bit slow.

To get reverse what should I do?

6

@cral79,
If you are using the Elevator (pitch) joystick for the throttle, pulling the Elevator joystick back towards you should cause the rover to go backwards.
If it does not go backwards, then you have something wrong with your configuration.
Regards,
TCIII ArduRover2 Developer

7

Hi,
the problem is when you calibrate at which the throttle positioned lowest value instead of middle value when you click complete button.

That’s all

8

TCIII, power seems to be ok now (used the pm)

btw: do I have to use the other side of the main power on the PM? could i connect my chartplotter/fishfinder combo to this?

But there are still some mysteries to the motor controll

When putting everything on the water it runs the engines for a few bursts, then it waits, and a few more burst, with the throttle on the RC controller in forward, same for backwards or when I turn one or more burst, then a little break.

Took the boat up, and tried to run it on a table.

it runs one motor, first little to the forward, then backwards then a longer burst forward, then a few small burs, then a longer burst backwards (with longer, I guess 2-3 sec, the short burst are 1 sec or less)

From the MP log

[quote]ArduRover v2.45 (5b1ac474)
ArduRover v2.45 (5b1ac474)
Warming up ADC…
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…

Ready to drive.
init home
Warming up ADC…
Warming up ADC…
Warming up ADC…
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Warming up ADC…
Warming up ADC…
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…
Initialising APM…
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…
Initialising APM…
Initialising APM…

Ready to drive.
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…
Initialising APM…
Non-Nav command ID updated to #255
init home
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…
Initialising APM…
Initialising APM…
Initialising APM…
Non-Nav command ID updated to #255
init home
Non-Nav command ID updated to #255
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…
Initialising APM…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…

Ready to drive.
init home
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…

Ready to drive.
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…

Ready to drive.
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…

Ready to drive.
init home
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Warming up ADC…
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…

Ready to drive.
init home
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Beginning INS calibration; do not move vehicle
Warming up ADC…
Beginning INS calibration; do not move vehicle
<startup_ground> GROUND START
Initialising APM…

Ready to drive.
init home[/quote]

This boat will only travel very slowly, around 2-3 mph max, does this make any trouble for the system?

Thanks

Carl

9

@cral79,
I suggest you post your project on the ArduBoat User Group Discussion Forum and provide pictures of your setup and attach your Full Parameter List as a text file.
You can save your Full Parameter List by using the Save button when you have the Full Parameter List screen open on the Mission Planner,
Regards,
TCIII GM