fischertechnik community forum

The Lego Time Twister is what inspired me to build this thing. Different mechanics of course.

http://www.ftcommunity.de/categories.php?cat_id=2586

Regards,
Willem Evert.

Where's the new FtMsclib.dll? I don't see any new downloads on fischertechnik.de.

Willem Evert.

This error can occur when there is a type mismatch between a command and a variable or constant. One is integer, the other floating point. Check they're all integer or all floating point.

Regards,
Willem Evert.

Most FT applications will likely use an accelerometer to find out where up or down is. That means accelerometer readings in the -g to +g range. The problem using the ADXL330 with the TX directly is that in the -g to +g range, its readings will vary from 1.2V to 1.8V (1.5V +/- 300mV/g). That means th...

Rien, Well, Carel provided some bed time reading... The easiest way to determine the Kalman parameters is by trial and error. Of course there's theoretical input (like expected noise is in the order of X mV), but in practice what I do is I record the measured values in a list, save it as a .csv file...

Hi, I took a look at what the TX counters are capable of doing in terms of frequency and pulse width, as I had trouble making them work at anything close to the specified 1kHz. In short this is what I found: - The fast counters can realistically only handle about 500Hz with a reasonable duty cycle t...

@Ad2: I used just the accelerometer to recreate rei_vilo's experiment. In fact, I used only 1 axis (like rei_vilo) and took an arcsin to get the angle, which is an approximation at best, as you point out. Accelerometers typically do not have a linear response (mine doesn't): the response is less at ...

Carel, P-control only works in the simplest cases, with very slow results. You almost always need at least the derivative or integral term. There are simple manual tuning procedures, such as described here http://en.wikipedia.org/wiki/PID_controller#Manual_tuning , and the Ziegler–Nichols method (sa...

Hi (or Bonjour, but that's about as far as my French goes ;) Interesting problem. I was able to get it to work with a PID controller and a Kalman filter. You have to apply a Kalman filter to the accelerometer data to be able to do anything useful with it (although yours seems pretty noisy). A simple...