> Hello ... > After the recent autopilot update , altitude hold doesn't work anymore for > me , (using pi-simple-controller) .... > Im not sure what effect to expect with the anti-windup addition , but my > guess is it's just exposing my poor > configuration. Syd,
if you are referring to the b1900d or the Bravo, the only autopilot controllers that could be affected by the patch might be for the b1900d - Vertical Speed Hold - Descent FPM - IAS and the Bravo - Vnav Hold 1 Unless I didn't introduce a bug, pi-simple-controller with a Ki of zero (aka pure gain) should not show a behaviour other than before the change. Curt made a nice description of anti-windup at http://www.flightgear.org/Docs/XMLAutopilot/node3.html <quote> Integrator wind up can occur when the system simply can't get to the target value, even at full control input. For instance a large truck commanded to go 90km/hr might slow to 70km/hr on a steep hill even at full throttle. During this time while climbing the hill, the integrator term is accumulating a tremendous amount of error. This is called integrator windup. Once you hit the crest of the hill you have to overshoot the target speed for a while to ``unwind'' the integrator term (which at this point may have grown very large.) This can cause you to significantly over-speed for as long as you were undershooting the target. This can lead to many unsafe and unstable situations so ``integrator windup'' is generally considered an undesirable </quote> Please let me know, if I can help fixing the problem. Torsten ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
