How do we centralize our UR5 so that all joints are completely straight/level with the base?

erin_thomas 2019-09-10

How do we centralize our UR5 so that all joints are completely straight/level with the base and stay that way?

Struggling to get the robot to move down and then up without the joints moving and becoming out of line. May this be because we are using MoveJ and should be using MoveL? Will we need to reset all the waypoints if we change to from MoveJ to MoveL after setting them?

Loïc 2019-09-10

My first answer is : save your program, try to change MoveJ with MoveL and see what happens. Trying things is the best way to learn. If it doesn't work you'll load your "old" program!

If I understand what you want to do, you just want the shoulder to move?

If I'm right, check the value of all the other axis of your two waypoints, they have to be exactly the same.

If there is still some problems, maybe it's because your payload and/or center of gravity is not correct.

Do you have the same problem with different speed?

matthewd92 2019-09-10

I will often set the joints at 90 degree angles so that my end effector is parallel with the base of the robot and then will use the arrows to move up and down so that I am going in a straight line to set the points. A moveL will keep the end effector moving in a straight line, a moveJ prioritizes joint efficiency over the TCP position, you will wind up in the same pose once the move is complete but there is a chance the TCP will take an arc to get there.

I agree with @"Loïc" that the best way to learn is to try something. Just as an FYI, you can also always get back to the last saved version of your program. Each time you press save, UR creates backups of the program as well. They keep the last 10 backups of the program with *.old0 being the newest backup. When you go to the open file screen you can change the file extension that it shows to be any files, this will show you the backups which are *.old0 to *.old9 once you have 10 backups.