[joonasten]

Hello,

I'm trying to construct a robot station with a robot which is on a linear track and two 2 axis turn tables on both sides of robot station. But I've ran into a problem with modelling two axis turn tables which is turning out to be quite the head scratcher.

My 2 axis turntable is not so different from the norm. So user error is the problem in this case. I don't quite understand how to set up the axes to turn the right way. I've gotten elbow to turn the right way but then the wrist is also turning like the elbow. I don't understand what Fa Fb Fh are meant to do or be. I guess turning points? How do I set them properly? A2 & Theta2 are apparently some kind of distance between the joints but I'm not sure.

Could some one explain to me how I could do this 2 axis turntable?

Could the step files origins mess things up? I've "fixed" them by moving them to joints rotation point but I'm not sure if that's needed. I've been able to assemble them with ease now because I can use measure tool to get mating surfaces point and copy paste that to be joints new location so I think that might be correct.


I've attached some files for you. Please take a look and tell me where I messed up thank you!

[Alex]

Having alpha 2 at 180 makes the two joints rotate along parallel axis. You need to set it to 90. 

Since your base is not at the center of rotation of J1, you add this "shift" in HB. Normally this would only mean a shift in Z, but since your reference Frame was not properly centered on the J2 axis of rotation, I also had to add a shift here.

See attached robot. (You may still need to shift the end effector in z)

[joonasten]

So like this? I'm still having a hard time to what these are refering to but I think I got it working.