I think what you have is a circular link. That means a parallelogram type geometry. I have a robot arm like this too but mine is MUCH smaller and lower cost.
Mine is nearly identical to this arm on Amazon. .amazon.com/Blesiya-Professional-Aluminum-Mechanical-Educational <https://www.amazon.com/Blesiya-Professional-Aluminum-Mechanical-Educational/dp/B07LCNBJJL/ref=sr_1_16?keywords=6dof+arm&qid=1553194112&s=gateway&sr=8-16> Notice that these are two motors on the shoulder and the "elbow" is pushed by a link. I think we have the same geometries, except for scale. The way to model it using DH is to re-draw the robot arm. Make a paper drawing of an equivalent arm that has a motor on each axis and no circular links and no passive links. You WILL need to transform the shaft angle of the moved motor. I don't use MK for this. I like "move it" but still DH parameters really only work for serial links so the trick is to model your arm as a serial link arm, just pretend the elbow motor is on that elbow and it's shaft angle is a function of the base motor shaft angle. This geometry is VERY common and yes there are names for it but most people call them palletizing robots. THese robots need to lift heavy loads, like bags of dog food off belts and place them on wood pallets so the motors are plased in the base and force transmitted to push rods. Most are only 4-DOF A Google search for "palletizing robot kinematics" will ,give tons of information. But "cheating" works. Remove the pushlinks and move the motor and make DH parms for that. The later "fix" the elbow motor shaft angle. . The arm in the above link is like mine in that it uses model airplane servos. These are very inaccurate and are open loop. So the plan is to close the control loop with a video cameras. This is not something MK was designed for hence using Moveit. moveit.ros.org Then I find I need to sychronize the video shutters so that is on hold for now. On Thu, Mar 21, 2019 at 6:45 AM yomin estiven jaramillo munera < yejm...@gmail.com> wrote: > Hi guys is me again, our kinematics problem have progressed, this is > because we are sure that our D-H parameters were correctly extracted, but > seems that our robot couldn't be defined with this parameters. > I'm saying this 'cause our robot is a miller MR 2000 and is very old, it > is moving how you can see in the follow link > > https://www.youtube.com/watch?v=Hp0gVXj5u-I&feature=youtu.be > > the D-H parameters could define the kinematics but when a joint depend of > the before one, but in this case our joint 2 is not changing the > orientation of our joint 3. The joint 2 is able to change the position on > the space of the final tool, but is unable to change its orientation on the > space. this kinematics is obviously very different to PUMA kinematics and > we are doubting about DH parameters can solve this. > is there any name for this kind of kinematics? > could i solve this using D-H parameters? > could i solve this using genserkins? > All my axes are set like angular joint, could that involved in a possible > solution? > > <https://www.youtube.com/watch?v=Hp0gVXj5u-I&feature=youtu.be> > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
