Hello everyone,
I've developed sort of an "upgrade module" (for lack of a better name) for the UHU based servo drives. This module is pin-compatible with the original UHU chip but allows you to use step-frequencies of 1Mhz or more and the encoder inputs are capable of tracking the encoder at speeds up to 2.5Mhz.

Here's a photo of a prototype mounted on the HP-UHU:


Other features are:
* Velocity and acceleration feed forward.
* Sliding scale following error.
* Data recorder (plot following error, PID output, motor velocity etc).
* Servo loop rate 1220-2500Hz (adjustable in 10 steps)
* Antidither function with setable range and scale for the PID gains.
* Output offset for unbalanced loads.
* Digital encoder filter for increased noise imunity.

Here's a [nomedia="http://www.youtube.com/watch?v=U-jrxK7u_34"]YouTube- Servo module 1.avi[/nomedia] video showing the module running on the HP-UHU driving a servo motor equipped with a 3600line encoder at ~3900rpm (936kHz step frequency).

Here are links to a preliminary datasheet and a preliminary manual.

What I'm currently looking for is 3-4 volonteers that are interested in trying/testing a module. I'll give you one module for free and in exchange you give me feedback on the operation of the module and its documentation which I linked to above. What's good, what's not good, what's missing - that sort of thing. I promise to do my best to sort out whatever problems we may find but I give no gurantees what so ever.

I've been testing the module myself for quite some time without having any real issues (lock-ups, motor run-away etc) but you need to understand that I can not be held responsible for any damages to humans or equipment that, in a worst case scenario, may be the result of using the module.

Once we've sorted out any bugs/issues/problems you may, if you like, send the module back and have its firmware updated and then returned to you free of charge - you pay shipping one way. (The firmware is not open source and, for the record, is not based on any other open source servo project code.)

I'd appreciate if you, as a beta tester of the module have a general understanding of how a closed loop servo system works and how to tune it - it'll make any problem solving neccessary a lot easier for both of us.

General questions, if there are any, in the thread please. If your interested in testing a module please PM me here on the zone or E-mail me at: henrik [at] henriksplace [dot] se

/Henrik.