Variable Table Motor Result (output) Dosent match the limit specified

Pioneer
Pioneer

Hey guys,

 

             I was using variable table motors to drive an assembly and i realised that it is not working as expected.

            I specify a number in the limit but it dosen't reach that number it either crosses it or stops before limit.

            Please check the attached assembly. (  i created it for an example)

 

If i lower the speed the result is close to expected. ( 3cm/s works in the example but 5cm/s wont work)

Please HELP.

 

Has anyone experienced this kind of porblem ?

Any help is appreciated.

 

Thanks,

Balaji

5 REPLIES

Re: Variable Table Motor Result (output) Dosent match the limit specified

Phenom
Phenom

Hi Balaji:

 

Try increasing the duration of the motor.

 

~Tushar

 

Re: Variable Table Motor Result (output) Dosent match the limit specified

Siemens Phenom Siemens Phenom
Siemens Phenom

Hi Bilaji,

 

Just because you have set a limit of 20 mm, that does not mean the limit will be reached - it just means that that's the most that it can travel. As Tushar mentioned, to reach the limit you would need to increase the motor duration since it is only 4 frames. However, I would log an IR on this because it looks like there is a problem. Doing the math, the motor velocity is 50 mm/s (5 cm/s) and the frame rate is 15 frames/s, so the part should move 3.33333 mm/frame. Since the motor duration is 4 frames, that means the part should move 13.33332 mm, meaning the dimension with value 400 should now become 386.67. Running the simulation, you will see that the final value is now 383.33 which is not correct. If you use the next frame arrow to step frame by frame from the beginning, I noticed the following:

  • The first time you press it, there is no motion and the frame indicator doesn't move
  • The next press moves the frame indicator to frame 1 and no motion - as expected
  • The next press moves the part 3.33 mm and the frame indicator disappears - this is unexpected since the motor duration has not started yet - the frame indicator should just advance to frame 2
  • The next press moves the part back to the original position and the frame indicator reappears at frame 1
  • The next press moves the part 3.33 mm and the frame indicator moves to frame 2 - this is unexpected since this should now be the starting point and the part should not have moved at this point
  • Continue until the end of the motor duration. The part is now 3.33 mm farther than it should be.

 

Greg

Re: Variable Table Motor Result (output) Dosent match the limit specified

Pioneer
Pioneer

Ty @Tushar for the help.

 

Ty @GregLuckett for the help.

 

I dint know how the limits worked. I thought the motor duration would be set as per speed and Limit specified and the max limit would be reached at the end of the duration.( i checked the "use motor limits as duration if  defined") thinking it would automatically do it Smiley Very Happy

Thanks for your help. Smiley Happy 

 

 

 

Thanks,

Balaji

Re: Variable Table Motor Result (output) Dosent match the limit specified

Siemens Phenom Siemens Phenom
Siemens Phenom

balaji1991 wrote:

Ty @Tushar for the help.

 

Ty @GregLuckett for the help.

 

I dint know how the limits worked. I thought the motor duration would be set as per speed and Limit specified and the max limit would be reached at the end of the duration.( i checked the "use motor limits as duration if  defined") thinking it would automatically do it Smiley Very Happy

Thanks for your help. Smiley Happy 

 

 

 

Thanks,

Balaji


 

Hi Balaji,

 

You are correct - the duration is supposed to be defined by the motor speed and limit you have defined if that option is set when you add the motor to an animation. I didn't realize that was what you did. That seems to be broken - I would have expected the duration to be 6 frames instead of 4. I tried this with a linear motor and it also shows the same behavior as your variable motor. Please log an IR for this issue and for the other issue I mentioned above so that we can take a look at it.

 

Thanks,

Greg

Re: Variable Table Motor Result (output) Dosent match the limit specified

Pioneer
Pioneer

Ty @GregLuckett

I logged an IR and the number is 7598454

 

 

 

Thanks

Balaji