sutty Posted March 7, 2023 Share Posted March 7, 2023 (edited) Hi! It's one axis. Did tuning unloaded. IDE-Tune-tool says: NominalGain=4800 (unloaded) resp. 550 (loaded with 21,94 kg) Servo: 16kHz RTI: 2 kHz Topology: Motor #4 and Motor #24 (put-through only) cascaded Set Adaptive-Control-Parameters: Motor[4].Servo.NominalGain=4800Motor[4].Servo.EstMinDac=100Motor[4].Servo.EstTime=160Motor[4].Servo.MinGainFactor=1Motor[4].Servo.MaxGainFactor=9Motor[4].Servo.MinW=0Motor[4].Servo.MaxW=0Motor[4].Servo.MinDR=0Motor[4].Servo.MaxDR=0 Put load with 21,94 kg (total of 100 kg possible) on. Motor[4].Servo.GainFactor remains all time at 1!! Motor[4].Servo.EstGain wont go above 0.02 Lowering MinGainFactor would lower GainFactor during accel/deceleration equally to MinGainFactor By the way setting MinGainFactor = MaxGainFactor = 9 would give a nice and stable setup with 21,94 kg load. I am really rookie-like - but can anybody show me a good practice example?!! Would I absolutely have to also set MaxW, MinW, MaxDR and MinDR? Thanks and regards, Anton Edited March 7, 2023 by sutty added motor-topology Quote Link to comment Share on other sites More sharing options...
steve.milici Posted March 13, 2023 Share Posted March 13, 2023 MaxW, MinW, MaxDR and MinDR are only used if you intend to implement “Gain Scheduled Adaptive Control”. I might suspect that at your servo frequency of 16KHz your setting of Motor[4].Servo.EstTime=160 may be too low to acquire sufficient “good data”. The “Power PMAC User’s Manual” suggests 100-500 at the default servo rate of 2.26KHz. Your servo rate is seven times faster. See if increasing this provides better results. Quote Link to comment Share on other sites More sharing options...
sutty Posted March 14, 2023 Author Share Posted March 14, 2023 Hi Steve! I rised EstTime up to 3000 - no improvments at all. I have to mention again that that ABS(Motor[4].Servo.EstGain) wont rise above 2e-2 in no case. Motor[4].Servo.NominalGain=4800Motor[4].Servo.EstMinDac=100Motor[4].Servo.EstTime=300Motor[4].Servo.MinGainFactor=1Motor[4].Servo.MaxGainFactor=5 Motor[4].Servo.NominalGain=4800Motor[4].Servo.EstMinDac=100Motor[4].Servo.EstTime=3000Motor[4].Servo.MinGainFactor=1Motor[4].Servo.MaxGainFactor=5 Quote Link to comment Share on other sites More sharing options...
steve.milici Posted March 14, 2023 Share Posted March 14, 2023 Is Motor[x].Ctrl is set to Sys.AdaptiveCtrl? Quote Link to comment Share on other sites More sharing options...
sutty Posted March 15, 2023 Author Share Posted March 15, 2023 (edited) Yes, it is! When I set Motor[4].Servo.MinGainFactor = Motor[4].Servo.MaxGainFactor (which forces Motor[4].Servo.GainFactor to that value) = "GainFactor" I calculated according several NominalGain-estimations, and it works from 0 to 100 kg. For example I tune the 100kg system. Estimate Nominal Gain for 100 kg (around 50) and for 22kg (around 500). So I set Motor[4].Servo.MinGainFactor = Motor[4].Servo.MaxGainFactor = 50/500 = 0.1 which forces Motor[4].Servo.GainFactor = 0.1. Might the cascading of motor #4 and #24 be a issue? Edited March 15, 2023 by sutty Quote Link to comment Share on other sites More sharing options...
steve.milici Posted March 15, 2023 Share Posted March 15, 2023 Yes it would be. Decouple the cascaded loop first. Then setup the Adaptive Control. Quote Link to comment Share on other sites More sharing options...
sutty Posted March 16, 2023 Author Share Posted March 16, 2023 Hi Steve! Unfortunately it is quite a deal to de-cascade the 2 loops. At least at the moment I cant spend time to do so. ... I will see in about 1 or 2 weeks and get back to you as soon I know more.. However, Is there a strict no-go for cascaded loops? Bye, Anton Quote Link to comment Share on other sites More sharing options...
steve.milici Posted March 16, 2023 Share Posted March 16, 2023 No, it is probably not, but it is outside my “body of knowledge”. I will see if one of the “servo experts” have any comments. Quote Link to comment Share on other sites More sharing options...
sutty Posted March 20, 2023 Author Share Posted March 20, 2023 Ok. Ask your experts, I will test it by next chance. Quote Link to comment Share on other sites More sharing options...
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