| ??? 11/27/04 22:44 Read: times |
#82098 - Great Stuff ! Responding to: ???'s previous message |
Hi Bruce,
FINALLY moved this thread into the regions we need to discuss ! Thanks for the tips. I don't think his method was Ziegler-Nichols. AFAIK that works on non-sampled control loops, operated open loop. Parameters are selected from simple measurements of the time to reach saturated output ? His limit cycle method hits the system with a square wave input, closed loop, with unity coefficients for PID. The square wave control signal was designed to kick the system within it linear range. Then he measured the output amplitude and phase and did some magic...I think he actually understood some of the stuff in Astrom and Wittenmark,"real time adaptive control" The method I have used is to turn off the I and D terms, then increase the P until it starts to oscillate and add I until it stops again. Its crude but works 8 out of 10. Steve |
| Topic | Author | Date |
| help about pid | 01/01/70 00:00 | |
| Floating point? | 01/01/70 00:00 | |
| Keil floating-point performance | 01/01/70 00:00 | |
| Search the forum | 01/01/70 00:00 | |
| Floating Point Vs Mixed point | 01/01/70 00:00 | |
| You mean Fixed Point | 01/01/70 00:00 | |
| Mixed not Fixed | 01/01/70 00:00 | |
| Warnings about Floating Point | 01/01/70 00:00 | |
| Shortcuts | 01/01/70 00:00 | |
| Implied aka Fixed point | 01/01/70 00:00 | |
| Another Shortcut | 01/01/70 00:00 | |
| Answering the question | 01/01/70 00:00 | |
| Autotunning? | 01/01/70 00:00 | |
| PID Tricks and Tuning | 01/01/70 00:00 | |
| Great Stuff ! | 01/01/70 00:00 | |
| I followed your idea... | 01/01/70 00:00 | |
| Another couple tricks | 01/01/70 00:00 | |
| tests | 01/01/70 00:00 | |
limit cycle tuning | 01/01/70 00:00 | |
| PID to control a Peltier | 01/01/70 00:00 | |
| An idea to try | 01/01/70 00:00 | |
| very fast 20ms ??? | 01/01/70 00:00 | |
| 20.000, not 2000. | 01/01/70 00:00 | |
| very fast 20ms ??? | 01/01/70 00:00 | |
| in points... | 01/01/70 00:00 |