Speed/Thrust Limit in Manual Mode

Hello everybody,

after extensive searching the web as well as this board I could not find an answer and now im suspecting that the feature i am looking for simply is not there … but I still think there is a chance that I just overlooked it.

Is there a way to limit the maximum value that the apm code outputs to an ESC? I would like to testdrive my rover (skid steered) inside and dont want to run into things all the time.

Yes I could do it on my RC remote, but I want to migrate to Joystick control later on, so it would be great if the APM could set an artificial limit on the control signal. Would be even better if the input was scaled so that I had a more fine grained control.

I found several sources talking about how to limit things for autopilot modes, but nothing for manual control …

Thanks for your help!

@blubbi321,
The following two parameters will control the rover velocity:
Target cruise speed in auto modes (APMrover2:CRUISE_SPEED)
The target speed in auto missions.
•Range: 0 100
•Increment: 0.1
•Units: m/s

Base throttle percentage in auto (APMrover2:CRUISE_THROTTLE)
The base throttle percentage to use in auto mode. The CRUISE_SPEED parameter controls the target speed, but the rover starts with the CRUISE_THROTTLE setting as the initial estimate for how much throttle is needed to achieve that speed. It then adjusts the throttle based on how fast the rover is actually going.
Range: 0 100
•Increment: 1
•Units: Percent

Regards,
TCIII AVD

@TCIII:
yes i found those … however i need limits on the maximum speed assigned to an esc when in manual control mode, ie i want to limit the maximum speed the rover goes when i directly control it with my rc remote (as well as with a joystick later on)

is there any option i can set in apm to achieve this?

@blubbi321,
In the full parameter list you can set the MIN and MAX values of the servo output that is controlling your ESC or you can reduce the maximum value of your transmitter’s PWM output for whatever transmitter channel you are using for your throttle.
Regards,
TCIII AVD

I have tried to lower the MAX value of my throttle channel (reduced 1980 (calibrated) to 1600) … however this made the wheels spin at ~70% throttle without me touching the remote.

Did I do anything wrong?

@blubbi321,
What brand of R/C transmitter are you using?
Is it a Futaba?
Regards,
TCIII AVD

Yes, an old FC16

@blubbi321,
What joystick axes are you using for the speed control (throttle) of the rover?
If you are using the throttle joystick, if I remember correctly, the output of the Futaba throttle channels is the opposite (reverse) of other R/C transmitter manufacturers.
In other words, full forward is 1000 us while full reverse is 2000 us.