All feeders have a settle time (U parameter) configuration. This is safe and slow. All servo has an operating speed. If the firmware could calculate the servo position then the settle time is only a safety parameter.
Another advantage is that if the firmware calculates the position, it is also possible to execute slower advance than the operating speed, preventing component jumping.
All servo has an operating speed. For example SG90 servo it's about 0.1s/60° (or 600°/s).
The firmware use degree/ms. So 60°/0.1s is 60°/100ms is 0.6°/1ms.
The new parameters are in degrees/milliseconds (°/ms) unit. It's a float number.
- It's range is from: 0.004 to 256 °/ms range. (4°/s .. 256000°/s)
- Resolution is 1/256 °/ms.
- 0 value means speed control disabled (default value)
After parameter write a rounding is applied and stored.
If speed control used, then the minimum speed for advance and retract is the max speed, that the servo can handle at that direction.
In this case the settle time could lower to 30..50 ms, because servo signal repeat time and motor movement is settle after 30..50 ms.
Advance speed in °/ms. It's minimum the operating speed, but can be slower.
Retract speed in °/ms. It's minimum the operating speed.
With half slowed advance and full speed retract on SG90:
M620 N0 A90 B44 C15 F4 S0.301 R0.602 U30 V544 W2440 X0
S0.301 = Advance speed: 30.1 °/0.1s S0.602 = Retract speed: 60.2 °/0.1s U30 = Settle time: 30 ms
For a 90 degree advance this is: 299 + 30 ms = 329 ms For a 90 degree retract this is: 150 + 30 ms = 180 ms
The default settings are: S0.000 R0.000 U240
Advance and retract speed disabled, settle time 240 ms