Technical Report: Fast Robot Arm Inverse Kinematics and Path Planning Under Complex Obstacle Constraint

Described here is a simple, reliable method for rapid computation of robot arm inverse kinematic solutions and motion path plans in the presence of complex obstructions. The method is based on a restricted form of the MSC (map-seeking circuit) algorithm, optimized to exploit the characteristics of practical arm configurations. MSC representation naturally incorporates both arm and obstacle geometries. The consequent performance on modern hardware is suitable for applications requiring real-time response. On high-end GPGPU hardware computation of both final pose for an 8 DOF arm and a smooth obstacle-avoiding motion path to that pose takes approximately 200msec.

A System View of the Recognition and Interpretation of Observed Human Shape, Pose and Action

There is physiological evidence that our ability to interpret human pose and action from 2D visual imagery (binocular or monocular) engages the circuitry of the motor cortices as well as the visual areas of the brain. This implies that the capability of the motor cortices to solve inverse kinematics is flexible enough to apply to both motion planning as well as serving as a generative model for the visual processing of human figures, despite the differing functional requirements of the two tasks. This paper provides a computational model of the cooperation between visual and motor areas: in other words, a system view of an important class of brain computations. The model unifies the solution of the separate inverse problems involved in the task, visual transformation discovery, inverse kinematics, and adaptation to morphology variations, using several instances of the Map-seeking Circuit algorithm. While the paper is weighted toward the exposition of a neurobiological hypothesis, from mathematical formalization of the problem to neuronal circuitry, the algorithmic expression of the solution is also a functional machine vision system for human figure recognition, and 3D pose and body morphology reconstruction from monocular, perspective-less input imagery. With an inverse kinematic generative model capable of imposing a variety of endogenous and exogenous constraints the machine vision implementation acquires characteristics currently unique among such systems.