> -----Original Message----- > From: leee [mailto:l...@spatial.plus.com] > > > > ie if u stick in a new value to the FDM then it will react.. That > > sucks in my oioiion.. I how have to create my own craqo to make > > the model. that sucks to me.. > > > > pete > > You really need to chill a bit. Just moaning about things isn't the > best way to go about getting stuff fixed. > > Anyway, in short, this 'problem' such as it is, is largely due to > the rates at which the autopilots are run within FG. In real life, > autopilot controllers, and the sensors that feed them the data they > need to work with, run at much higher frequencies than are possible > within the FG framework. Ideally, you want to be able to run the > autopilots at several to many kHz but in FG, although you can > specify very high rates in the autopilot config, you are > effectively limited by the frame rate, so not only do they run much > more slowly than is desirable but they also run at varying rates as > the frame rate changes. > Lee
First, thanks for the quick into to Flightgear´s autopilot. I think that your premise that autopilots need to run at very high frame rates is not realistic. When I first got into autopilots and simulation, back in the 60´s, all of our models had as the final element a 0.1 second low pass filter which simulated the control surface actuator. This turns out to be a reasonable approximation for most actuators and is very simple to implement both in a analogue computer (which is all we had then) and in digital ones. As there is such a filter in the inner loop means that there is no need to simulate anything which has a faster response time than this. Therefore there is no need to run the autopilot at high frame rates. 10 or 20 per second is perfectly adequate. Many of the outer loops (e.g. the heading mode) of the autopilot can in practice be run at much slower frame rates as the response of the aircraft is quite slow. Alan ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
