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Help on IK for Robot Arm

I’m working on a project where I need to have a robot arm that grab an item and put it somewhere ( very similar to this one )

The project will work using the Vive, so everything is in VR.

The logic behind the entire process is quite easy to do ( overlap box the robot arm will pick the product and put it somewhere else ), but I’m having troubles with the IK setup for the Robot Arm.

I’ve build the skeletal hierarchy in Maya ( very simple, 10 joints placed where the center of rotation of each piece is ), imported in UE4 and create the AnimBP.

First I tried to build something very similar to the setup done by Mitch VR Lab ( in short the head is driven by the orientation/position of the HMD, modified in order to work with a box which drives the robot arm ), but I notice that, using the Two Bone IK, only 2 joints ( the last two ) are affected by the IK setup.

I also tried to use Fabrik, and looks like the entire joint chain is affected ( since I’m choosing the end joint and the root ).

So using Fabrik is ok, but the main issue tis that the joints rotate on each axis, and I want to be able to lock the rotation on some axis, so that the robot will behave based on its mechanical constraints.

I tried to use the Transform bone node, but if I override ( Replace existing ) the rotation, the IK breaks.

So, is there a way to use Fabrik ( or a valid alternative ) in order to setup a custom IK system?

Cheers

Hey Enter Reality,

Currently I’m having a similar problem, but with much more simple movement. Did you solve the issue in the meantime and could help me out?

Sorry for digging this thread up though.

Greetings,

Gordon

Hi Gordon,

Short answer is no, but I’m about to create a different solution using a custom setup with Blueprints and float values to drive the robot, so no IK within UE4, but rather a custom IK system, since looks like that what I have in mind is not possible.

I’ll be releasing some CAD related tech demo in the near future ( kinematic assembly line, pick and place ) which will also integrate the robotic arm

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Hello Enter Reality,

I am currently trying to implement IK in Franka Emika Panda Robot. Though, I have implemented some basic movement using keyboard keys now, Can you help me out with your Blueprint approach to solve ( some pick & place movement )?

Thanks in Advance!

Cheers,
Akash Rabadiya