How to modify Drive > Angular > Max Force through Python code?

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How can I modify Drive > Angular > Max Force through Python code?

I tried using the following code, but it not work.

drive = UsdPhysics.DriveAPI.Get(prim, “angular”)

drive.GetMaxForceAttr().Set(target_mf)

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3

Hi, I don’t see why your code shouldn’t work. Did you make sure the prim path is correct? Anyway, here’s a more complete example for your reference:

from pxr import UsdPhysics, Usd
import omni.usd

# Get the USD stage
stage = omni.usd.get_context().get_stage()

# Get the joint prim (replace with your joint path)
joint_path = "/World/Robot/joint_name"
joint_prim = stage.GetPrimAtPath(joint_path)

# Determine the drive type based on joint type
if joint_prim.IsA(UsdPhysics.RevoluteJoint):
    drive_type = "angular"
elif joint_prim.IsA(UsdPhysics.PrismaticJoint):
    drive_type = "linear"
else:
    print(f"Joint at {joint_path} is not a revolute or prismatic joint")
    exit()

# Get or apply the DriveAPI
if joint_prim.HasAPI(UsdPhysics.DriveAPI, drive_type):
    drive_api = UsdPhysics.DriveAPI.Get(joint_prim, drive_type)
else:
    drive_api = UsdPhysics.DriveAPI.Apply(joint_prim, drive_type)

# Set the max force value
max_force = 1000.0  # Set your desired max force value

if drive_api.GetMaxForceAttr():
    drive_api.GetMaxForceAttr().Set(max_force)
else:
    drive_api.CreateMaxForceAttr(max_force)

print(f"Set max force to {max_force} for {drive_type} drive on {joint_path}")
4

I discovered today that my prim specification was incorrect, which is why Maxforce wasn’t changing. Thank you for your assistance and the example you provided!