RobotStudio event

Understanding DH Parameters in Robot XML

ji291 ✭

November 5 in RobotStudio

Hi all,

I am currently trying to wrpa my head around the DH parameters that are present in the PIM.xml for the IRB6400 robot.

When attempting todo forward kinematic calculations with the robot, I am not getting the same values as reported by the flexpendant.

XML Below:

<JointInfos>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="1" />

<Link Value="1" />

<Twist Value="0" />

<Length Value="0" />

<Rotation Value="0" />

<Offset Value="0" />

</Element>

<Element>

<NextJoint Value="9" />

<Link Value="-1" />

<Twist Value="0" />

<Length Value="0" />

<Rotation Value="0" />

<Offset Value="0.27" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="2" />

<Link Value="2" />

<Twist Value="-1.5707963267949" />

<Length Value="0.24" />

<Rotation Value="-1.5707963267949" />

<Offset Value="0" />

</Element>

<Element>

<NextJoint Value="8" />

<Link Value="-1" />

<Twist Value="-1.5707963267949" />

<Length Value="0.24" />

<Rotation Value="-1.5707963267949" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="3" />

<Link Value="3" />

<Twist Value="0" />

<Length Value="1.05" />

<Rotation Value="0" />

<Offset Value="0" />

</Element>

<Element>

<NextJoint Value="6" />

<Link Value="-1" />

<Twist Value="0" />

<Length Value="1.05" />

<Rotation Value="-1.5707963267949" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="4" />

<Link Value="4" />

<Twist Value="-1.5707963267949" />

<Length Value="0.225" />

<Rotation Value="0" />

<Offset Value="1.52" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="5" />

<Link Value="5" />

<Twist Value="1.5707963267949" />

<Length Value="0" />

<Rotation Value="-3.14159265358979" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="-1" />

<Link Value="6" />

<Twist Value="1.5707963267949" />

<Length Value="0" />

<Rotation Value="0" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="7" />

<Link Value="7" />

<Twist Value="0" />

<Length Value="0.4" />

<Rotation Value="-1.5707963267949" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="-1" />

<Link Value="8" />

<Twist Value="0" />

<Length Value="1.05" />

<Rotation Value="0" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="-1" />

<Link Value="9" />

<Twist Value="0" />

<Length Value="1.05" />

<Rotation Value="0" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

<Element>

<IsRevoluteJoint Value="true" />

<DHParameters>

<Element>

<NextJoint Value="-1" />

<Link Value="10" />

<Twist Value="-1.5707963267949" />

<Length Value="0.276" />

<Rotation Value="0" />

<Offset Value="0" />

</Element>

</DHParameters>

</Element>

With my understanding, where Link Value = '1', this represents the transofrmation of the base frame to link 1, and then Link Value = '2' represents the transformation parameters from joint 1 to joint 2. Although this raises questions about why there are more than 6 joint values

Please can someone inform me if I am correct?

Best Regards,

Joe

0

Categories