CalcJointT

Developer Tools
1

Hi,

I use CalcJointT to check if a Cartesian point is Reachable, and if yes, to keep its equivalent joints values.

I have a problem that sometime I get error (ERR_ROBLIMIT) when I use it.

To investigate it I took a point in Cartesian value which the robot give ERR_ROBLIMIT

I run a program which move the robot to that position :

The position was :

[[273.7763,**-297.6656,707.4647],[0.161286955593029,0.145771576665284,-**0.0468260793419564,0.974958708707968],[0,1,0,0],[8.999999E+09,8.999999E+09,8.999999E+09,8.999999E+09,8.999999E+09,8.999999E+09]]

So now, after running the program, this point is his current position.

Now if I ask the robot it current position, I get the same result but with different configuration : [0,2,0,-1]

If I run CalcJointT with the current position values [0,2,0,-1] I get error. Even if this point is his current position ?

If I run CalcJointT with (with the values [0,1,0,0]) I get ok.

I seem that:

A? When the robot ask to move with a specific configuration sometime it ignore it and use his current configuration.

A? The configuration may change the result.

Is there a way to run CalcJointT and ask to ignore configuration?

I need to check for a giving path (which may include 10 -50 robot position) if the robot can move in this path (all the point in the path are reachable for him) is there a better way to do it ?

Thanks

Avi

2

Hi avicohen,

From the manual

so no, you can’t tell it to ignore configuration. Then check that 0 degrees thing.

Also a note on singularities, check out the RAPID reference manual [Data types > confdata - Robot configuration data] or your robot manual. There you have a summary of how those configs are used etc.

And yes, since you are creating a JointTarget then the exact positions of the joints, ie configuration, is what you are asking for. So If you send in a [0,1,0,0] configuration then that is the positions of the arm that you are going to get, with the problem that, no the robot won’t usually twist 180A? in a single move like that. Especially if you are within the singularity quarter.

But how come you are asking RAPID questions in the Developer Center Forum?