Involuntary Servo Movements

Kwatters and others have seen a bad Servo Palsy problem in recent releases.
This post is to document the details and get to the bottom of it

What is it ? :

  • It only happens I believe to real hardware
  • kwatters can see the symptom very acutely on Harry
  • I do not see it with my pan/tilt - but using the webgui i can get mrlcomm errors if i move the lever for servo position around very quickly

kwatters says last october - "servo control and arduino control was rock solid back then."
Several new features have been added:

  1. TimerEncoders - an important restructure 
    http://myrobotlab.org/content/servo-updates
  2. And Arduino brownout recovery - which allows Arduino and Servos to recover after the Arduino suffers a power outage - it gives the user a nice error message too

  3. Modularity of ServoControl & ServoControllers - ability of different types of ServoControllers e.g. I2C, RasPi, etc to more easily be swapped with Arduinos and their interfaces conforming to the generic mrl pub/sub

I put considerable work into these features.  There should be a way to integrate them and remove servo palsy.

If you have experimented with the develop branch please let us know your experiences and we'll put an end to Servo Palsy ! 


Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
GroG's picture

Update : On my test system I

Update :
On my test system I have 2 servos (pan & tilt).   I can only generate MRL errors through the webgui with the tilt servo.  Under considerable testing I have not been able to make a single error with the pan servo.  I suspect now my errors have to do with the fact that my tilt servo is very electrically noisey ..

So, I have not been able to generate any errors from the webgui that are software related ...

I haven't tested speed control, which I'll do next

GroG's picture

Is Servo Palsy specific to

Is Servo Palsy specific to speed control ?