Advice for robot controller using opennurbs and grasshopper‽


I know that discourse.mcneel is not quite the right place for this question but since here are a lot of nice people ( who also know their stuff :slight_smile: ) please allow a slightly ot question. It’s worth a shot, even if no one has an answer.

I want to control a 7 dof robot arm with rhino/gh. More information about the robot can be found here:
franka emika;
There is a 1khz control loop setting the goal state for each consecutive step.

I am not an experienced (c++) developer so I would like to outline my current plan before I get to the xyproblem state:

I the next weeks and months I will try to implement this so any comment,advice or support is very much welcomed; Right now I have a working example with ros and moveit, if you want to have look in person: I am in berlin, you can contact me and just come by the lab to say hello :slight_smile:

the setup is as follows:
one robotarm (panda robot) contected to a rt ubuntu based pc (robotPC)
one windows pc running rhino and grasshopper (rhinoPC)

1 .set up a trajectory with a nurbscurve in grasshopper(rhinopc)
2. use grasshopper with udp sender to talk to a receiver at robotPC
3. send the controlpoints to the robotPC via udp
4. reconstruct the nurbscurve using openNurbs on the robotPC(ubuntu)
5. evaluate the curve at a rate of 1khz to get a valid goal for each timestep ~ very tricky see annotation*
6.when reaching the end of the curve, requesting new curve from gh
7. repeat 3-7

annotation*: there are certain parameters that have to be met: link, I am not quite sure how to ensure this

thanks again!

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btw: here is a video of the current setup(only simulation but it works with the real deal aswell) with ros, moveit and grashopper:
sadly moveit doesn’t generate very smooth motion, at least I don’t know how

A few plug-ins to explore which might help: