FABRIK: A fast, iterative solver for the Inverse Kinematics problem

Inverse Kinematics is defined as the problem of determining a set of appropriate joint configurations for which the end effectors move to desired positions as smoothly, rapidly, and as accurately as possible. However, many of the currently available methods suffer from high computational cost and production of unrealistic poses. In this paper, a novel heuristic method, called Forward And Backward Reaching Inverse Kinematics (FABRIK), is described and compared with some of the most popular existing methods regarding reliability, computational cost and conversion criteria. FABRIK avoids the use of rotational angles or matrices, and instead finds each joint position via locating a point on a line. Thus, it converges in few iterations, has low computational cost and produces visually realistic poses. Constraints can easily be incorporated within FABRIK and multiple chains with multiple end effectors are also supported.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights►FABRIK is a simple, fast, iterative Inverse Kinematics solver. ► It supports most joint types and chain classes. ► FABRIK supports multiple end effectors and it can handle end effector orientations. ► It produces visually smooth postures without oscillations or discontinuities. ► FABRIK can reach the desired position with very low computational cost.