Robot standard DH model establishment method-analogy
Puma560 robot standard DH parameter table is as follows
: Theta: joint rotation angle
D: link offset
A: link length
Alpha: link torsion angle
theta d a alpha
1 q1 0.0000 0.0000 90
2 q2 0.0000 0.4318(a2) 0
3 q3 0.1500(d3) 0.0203(a3) -90
4 q4 0.4318(d4) 0.0000 90
5 q5 0.0000 0.0000 -90
6 q6 0.0000 0.0000 0
The Puma560 robot model is shown below
Refer to the robot model of puma560 and observe the robot model of Staubli TX90. The model is as shown below:
By comparing the type of puma560 robot and Staubli robot, the difference is that the Z axis of staubli robot joint 1 and the Z axis of joint 2 have an offset of 50mm, and the offset value is a1 of staubli robot; joint 3 of staubli robot The Z axis of the p560 is in the same plane as the Z axis of the joint 4, and the Z axis of the joint 4 of the p560 is offset by a distance of a3 relative to the Z axis of the joint 3. Therefore, the d3 value of the staubli machine is 0, and There is a value for the a3 value of p560.
Therefore, the standard DH parameter table of staubli robot can be written as follows:
theta d a alpha
1 q1 0.0000 -0.0500 90
2 q2 0.0000 0.4250(a2) 0
3 q3 0.0500(d3) 0.0000(a3) -90
4 q4 0.4250(d4) 0.0000 90
5 q5 0.0000 0.0000 -90
6 q6 0.0000 0.0000 0
From the above, the only changes in the DH parameter table are: a1 value is added, a3 value is cancelled, and a2, d3, and d4 values are changed.
The DH parameters can be verified with the function of the peter robot toolbox in matlab, and the staubli robot model is obtained as shown below:
The only indication that the actual situation is not consistent is that the X and Y directions of the robot base coordinates established by matlab are opposite to the actual robot base coordinate system. However, the state of the joint rotation angle of the robot at this time is the state most in line with the actual robot.
From this, take out a robot model, we can directly write its standard DH parameters, the following picture shows the Estun robot, Estun robot is one of the three giants of domestic robots, the overall performance of the robot is better, you can try it yourself Write about
