When setting up a motion analysis i have tried to add a linear actuator to a face and i am gettin an error stating that the mechanism has locked up. how do i find out which component the error is connected to or how to fix this error?
see attached file for error
Thanks Ian,
There's an awful lot of files so it would be too awkward to post the model. i defined the part moving relative to the motor and the simulation ran as i wanted it to, if i want the actuator to retract back to the original position following the initial motion do i have to define another motor to do this or what would you see as the best way to do this?
Regards
Laura
Hi Laura,
Yes, with actuators, the reference part is very important. To perform multiple movements, there are several options. You can use an oscillating function (and just to it for half a cycle) or you can use the expression field to specify multiple moves. When you define a distance move, it is smoothly changing position and starting and ending the move with zero speed. This uses what we call a STEP function. You can sequence a series of step functions in the function expression.
For example, to extend 500mm from 0-2 seconds and then retract from 4-5 seconds, the expression would be:
STEP(TIME,0,0,2,500)+STEP(TIME,4,0,5,-500)
The step functions a cumulative, so you can see I can just use delta values to adjust position.
Hope this helps,
Ian
Hi Laura,
It's very hard to say from the images what the cause is. I see that you are using flexible subassemblies. Provided that the part you are putting the motion on can be dynamically dragged in the top level assembly it should work. One aspect to keep in mind though, is that if the part with the motion on it moves relative to another component than changes position/orientation, you need to define that as the reference part in the motor definition (or it will lock up).
If you're able to post the model, others and myself on the forum will be able to give more feedback. If that's really an issue, then you need to post images showing the mechanism structure, the part the motion is on, the motion definition to be able to help further.
Cheers,
Ian