Link object question

[Charles L Hakes]

Hi all,

I am trying to model a robot arm as I see done in chapter 7.  I want to use ikine to get a table of angles to send to actual servos, but some of those are off by pi/2 in the way they are mounted.  I thought the first angle in the Link (table 7.1) could fix that, but can’t see that angle does anything, or else I am calling it wrong.  (?)  I guess I could “post process” the angles, but that would be way more inconvenient.  (By the way, the last three links are to just make it look more like the P560 model and those rotations are ignored.)

As an aside, any reason some of this stuff that was working fine in Matlab 2020a doesn’t in my more recent updates?

Charlie

Part of the code…

L1 = Link([0, 6.5, 2.5, -pi/2, 0])

L2 = Link([0, 1.5, 8.5, 0, 0])

L3 = Link([0, -1.5, 12, 0, 0])

 

% Connect those Link Objects

 

arm = SerialLink( [ L1 L2 L3 ],'name', '3-servo-robot-arm')

 

% robot.fkine([80 -30 50], 'deg')  this does not work - looks like

% still radians

 

q = [pi/2.2 -pi/6 pi/2.5]

 

P1 = arm.fkine(q)

 

figure(1)

arm.plot(q)