Finding singularity

[VISHWARATH T]

Hello all,

Is there a tool box function to evaluate the singularities for a given serial link robot?

[Felipe]

Yes. You can use the manipulability index to chack if the robot is on a singular configuration.

Ex.:

>> mdl_puma560

>> m = p560.maniplty(qn,'all')

m =

    0.0786

>> m = p560.maniplty(qz,'all')

m =

     0

>> 

In the case above, the Puma 560 is on a singular configuration when its junctions are in position qz. Therefore, the manipulability index is zero. 

The closer to the singular configuration, the smaller the manipulability index is (minimum is zero).

[VISHWARATH T]

Thank you for your reply. I want to know of all the joint configurations that can cause the singularity. Is that possible for a SerialLink robot?

[J Sumarac]

Hello,

I'm trying to find areas with low manipulability for a UR5 robot using maniplty function with Yoshikawa algorithm. I'm interested to know what the reference value for manipulability is. For instance, for a large set of random configurations, the manipulability was between 0.19 and 0.00000001 in my case. So what could be the cutoff value, below which you could say the manipulability is not very good? Also is there such a value for the Jacobian determinant?

Thanks in advance,

Jovan