Calibrating PWM ("PPM") servo remote control [SRO]

[b264]

When you use a PWM servo control, often called “PPM”, you need to calibrate the pulsewidths.

The way I do it is manually — I feel it works slightly better than the automatic approach.

I’ve covered both here.

Make sure you pair/bind the remote first.

How to bind the Mini Remote [Serious]

The 2.4GHz Mini Remote is my favorite transmitter for esk8. (buy from amazon)(buy from UK)(buy receiver only from AliExpress)(buy from AliExpress) To bind a receiver with a transmitter, you can follow the steps in this excellent video from @torqueboards [How To Pair 2.4ghz TorqueBoards Mini Remote Controller Instructions Tutorial] I’d like to add that there is a failsafe trigger position (the throttle value used if signal is lost briefly). To set this, you leave the receiver an…

[b264]

Automatic calibration

works aight

0. make sure the tool is connected to the ESC and RT APP is turned on
1. make sure the remote is connected and paired with its receiver and its failsafe is set
2. turn on the remote
3. read app settings
4. reset the calibrator
5. operate the throttle from one extreme to the other a few times
6. release throttle to center position
7. click apply
8. [optional] decrease deadband, 15% is rather high IMHO (10% seems better)
9. write app settings
10. turn off the remote and make sure the throttle stays within the deadband area (if not, redo the failsafe setting)
11. enjoy

[b264]

Manual calibration

works very well

0. make sure the tool is connected to the ESC and RT APP is turned on
1. make sure the remote is connected and paired with its receiver and its failsafe is set
2. turn on the remote
3. read app settings
4. with throttle in neutral, note the center pulsewidth and copy it above
5. write app settings
6. pull throttle all the way (forward) and note pulsewidth, and copy it above
7. write app settings
8. push throttle all the way (braking) and note pulsewidth, and copy it above
9. write app settings
10. edit the maximum pulsewidth so you can control the “tool” throttle up to around 104%
11. write app settings
12. edit the minimum pulsewidth so you can control the “tool” throttle down to around -104%
13. write app settings
14. [optional] decrease deadband, 15% is rather high IMHO (10% seems better)
15. write app settings
16. operate the throttle from one extreme to the other a few times, make sure it goes from -104% to +104% and rests around zero (and within the deadband), redo any numbers and click write app settings as needed
17. turn off the remote and make sure the throttle stays within the deadband area (if not, redo the failsafe setting)
18. enjoy

[b264]

Ideally, you want to be able to operate it from around -104%-ish to +104%-ish

with ​the center well within your deadband ( -0.1% and 7.0% below) even when you turn off the remote.

[xsynatic]

@b264

Ideally, you want to be able to operate it from around -104%-ish to +104%-ish

why’s that?

[b264]

That way if you want to maintain full throttle for extended periods of time you can relax your hand instead of keeping the mechanism crammed into the end stop. You can just keep it lightly pushed and not have the jitters as it flips back and forth between 99.5% and 100%. It’s effectively like a deadband, but for the ends of the throw instead of the middle.