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arXiv · 2609.29908

MorphIK: Morphology-Conditioned Neural Inverse Kinematics for Unknown Robots

Lennart Clasmeier·Jan Gerrit Habekost·Cornelius Weber·Stefan Wermter
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Abstract

Neural models can learn to generate various solutions to the inverse kinematics problem from data, but are usually limited to a single robot. We present MorphIK, a flow-matching model that solves inverse kinematics for revolute-joint-based kinematic chains it has never seen during training. The model uses a transformer architecture to encode the robot's morphology along with the target pose. This encoding then conditions a flow-matching head that generates poses from noise. Trained on purely synthetic data from procedurally generated robots, the model reaches a precision of about 5 cm on unseen real-world robots with 6 to 9 Degrees of Freedom. For higher precision, the model serves as an excellent Prior for further optimization algorithms, reducing error to less than 1 cm after a single step of Damped Least Squares optimization and to sub-1 mm error after 3 steps in most cases. Building on flow matching's generative capabilities to produce highly diverse outputs, our model can efficiently sample the robot's null space, providing a wide variety of configurations for the same pose. Thus, overall, MorphIK allows learning and generalizing neural inverse kinematics for a multitude of known and unknown robots.

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Lennart Clasmeier, Jan Gerrit Habekost, Cornelius Weber, Stefan Wermter. 2026-09-24. MorphIK: Morphology-Conditioned Neural Inverse Kinematics for Unknown Robots. https://arxiv.org/abs/2609.29908

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