Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!mcsun!ukc!cam-eng!tw800!ttj10 From: ttj10@eng.cam.ac.uk (T.T.Jervis) Newsgroups: comp.ai.neural-nets Subject: Re: Pole Balancing Problem Message-ID: Date: 4 Feb 91 01:13:03 GMT References: <665415070.18755@minster.york.ac.uk> Sender: ttj10@eng.cam.ac.uk Organization: Engineering Department, Cambridge University, England. Lines: 29 In-reply-to: george@minster.york.ac.uk's message of 1 Feb 91 13:31:10 GMT I have implemented Sutton and Barto's pole balancing work. I have obtained results that agree with those found in their paper. Without looking into your problem in detail, it would seem a sign may be astray. Incidentally, your comment regarding the reasonable behaviour of your simulation requires an assumption to be made as to the sense of "... e.g. pole at angle 10 degrees say, ..." with respect to your "... small velocity to left, ...". I found that working through the simulation equations myself sorted out any problems, especialy regarding the sign of angles and angular velocities, and helped in the assessment of the relevance of the simulation. Again, the equations I derived for myself were of the same form as those in the paper. I am incidentally running pole-balancing code on transputer hardware linked to a real pole rig of the same form as the simultion in Sutton and Barto's paper. Their controller needs to be modified for a plant with differing masses and inertias, but preliminary results would seem to indicate that an improvement in time to failure can be gained over a period of some tens of minutes of operation. I would be interested to hear of anyone else involved in this kind of control. Good luck with the code! -- _________ __ __ ___ /________/| /_/| /_ /\ /__/| Cambridge University |__ ___|/ | || | \ \/ || Engineering Department