topic Betreff: Drive constraint at a set speed / RPM in Inventor Forum

Drive constraint at a set speed / RPM

matt_jlt — Wed, 24 Aug 2022 11:53:47 GMT

I am trying to drive an angle constraint to achieve a specific RPM, but it doesnt seem to matter how i calculate it out, the motion doesnt match real time. I think i'm just going around in circles.

Can anyone help me work it out please? I have been trying to do work it out for ages.

I am trying to work out the combination of Pause Delay and Angle Increment to achieve a smooth and accurate motion (not rendered out to the video @ the framerate but displayed in the inventor window)

The speeds i want to target are 40 RPM + 80 RPM + 120 RPM.

Thanks, Matt.

Betreff: Drive constraint at a set speed / RPM

Lucas.dolinarVFXZU — Wed, 24 Aug 2022 12:20:21 GMT

when animating 360deg, the # of steps * delay will be the time per rotation.
but this is not meant to be accurate. just loading the screen might add delay in big assemblies.

Re: Drive constraint at a set speed / RPM

swalton — Wed, 24 Aug 2022 13:03:08 GMT

There are four ways to simulate motion in Inventor assemblies.

Manual Drag under-constrained components
Drive constraints
Inventor Studio
Dynamic Simulation

None of them target real-time movements during the animation. All of them depend on the complexity of the assembly and processor power to animate each time step.

Are you recording the animation, then replaying it with a video player?

I'd recommend Inventor Studio if you don't need to know the power/torque or other engineering data about the motion. I'd recommend Dynamic Simulation if you do need to know that kind of data.

Re: Drive constraint at a set speed / RPM

matt_jlt — Wed, 24 Aug 2022 14:05:31 GMT

Thanks everyone, I was hoping that it was just me not working it out correctly. I guess i could write an ilogic script to rotate it incrementally on a timer but its more complicated than i wanted.

I dont need any data out of it, I wanted to be able to just have it on the screen / a form and I could change the RPM value and it would update the rotation live and not have to render to a video.

Re: Drive constraint at a set speed / RPM

JDMather — Thu, 25 Aug 2022 11:24:49 GMT

@matt_jlt wrote:

I could change the RPM value and it would update the rotation live and not have to render to a video.

You can enter RPM in Dynamic Simulation.

The actual display (calculation) time depends on the number of time steps (think of as frames) calculated. After initial calculation playback is faster but not necessary corresponding to real time. Input Grapher can be used to have variable speed control.

Can you Attach an example assembly?

Re: Drive constraint at a set speed / RPM

JDMather — Thu, 25 Aug 2022 15:50:09 GMT

Re: Drive constraint at a set speed / RPM

matt_jlt — Mon, 29 Aug 2022 22:17:07 GMT

Thanks to everyone, I accepted the dynamic simulation as the answer although it wasnt exactly what i was hoping for it still did the job.

Thanks