I've written a function which should calculate the manipulability measure of my KDL::Chain. For this purpose I create a JntToJacSolver an execute the JntToJac-function with the current joint values as input.

So I get the resulting jacobian for the manipulability measure. Now my question is: leads this way to create a Jacobian to a correct manipulability measure sqrt(det(JJ^t))?

I have always values between 15000 and 20000 during a trajectory. Is this correct?

By the way: dou you have some papers about this topic?

## manipulability measure calculation with KDL::Jacobian

On Mon, 29 Sep 2008, manuelbirlo [..] ... wrote:

> I've written a function which should calculate the manipulability measure of

> my KDL::Chain. For this purpose I create a JntToJacSolver an execute the

> JntToJac-function with the current joint values as input. So I get the

> resulting jacobian for the manipulability measure. Now my question is: leads

> this way to create a Jacobian to a correct manipulability measure

> sqrt(det(JJ^t))?

If you do the calculation for the matrix multiplication, the determinant

and the sqrt correctly, yes! :-)

> I have always values between 15000 and 20000 during a trajectory. Is this

> correct?

No idea! This depends on so many things: chosen units, chosen reference

frames, actual configuration, ...

> By the way: dou you have some papers about this topic?

For example:

@Article{ doty-etal-itra95,

author = {Doty, Keith L. and Melchiorri, Claudio and Schwartz,

Eric

M. and Bonivento, Claudio},

title = {Robot manipulability},

journal = {IEEE Trans. Robotics and Automation},

year = {1995},

volume = {11},

number = {3},

pages = {462--468}

}

Herman

Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

## manipulability measure calculation with KDL::Jacobian

I've found this paper (Robot manipulability) but I have no access to view it:

http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel4/70/8824/00388791.pdf?tp=&isnumber=&arnumber=388791

or do you have it?

>If you do the calculation for the matrix multiplication, the >determinant

>and the sqrt correctly, yes! :-)

then it should be correct!

>No idea! This depends on so many things: chosen units, >chosen reference

>frames, actual configuration, ...

hmm...I have a KDL::Chain with 7 joints and an extra none-segment which is for the transformation in woorld coordinates, so the Chain has 8 segments (first segment is a none segment, and 7 segments with 7 rotational joints).

and the joints values are in radians.