{"title":"IK-Geo: Unified robot inverse kinematics using subproblem decomposition","authors":"Alexander J. Elias, John T. Wen","doi":"10.1016/j.mechmachtheory.2025.105971","DOIUrl":null,"url":null,"abstract":"<div><div>We present IK-Geo, a highly capable and computationally efficient open-source robot inverse kinematics (IK) solver. In this unifying approach, IK for any 6-DOF all-revolute (6R) manipulator is decomposed into six canonical geometric subproblems solved by intersecting circles with other geometric objects. Subproblems are efficiently solved in all cases including in a continuous and sometimes least-squares sense when a solution does not exist. This continuity requirement means IK-Geo finds all IK solutions including singular solutions and sometimes least-squares solutions. Robots with three intersecting or parallel axes are solved in closed form. All other commercially available robots have at least one pair of intersecting or parallel axes and are solved by searching over one joint angle. Fully general robots are solved by searching over two joint angles. Search solutions may be converted to a system of three or four polynomials in terms of the end effector pose in the tangent half-angle of one joint. A comparison with IKFast and the MATLAB Robotics Toolbox IK solver demonstrates that IK-Geo has faster computation and can solve more classes of robots.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"209 ","pages":"Article 105971"},"PeriodicalIF":4.5000,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mechanism and Machine Theory","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0094114X25000606","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
引用次数: 0
Abstract
We present IK-Geo, a highly capable and computationally efficient open-source robot inverse kinematics (IK) solver. In this unifying approach, IK for any 6-DOF all-revolute (6R) manipulator is decomposed into six canonical geometric subproblems solved by intersecting circles with other geometric objects. Subproblems are efficiently solved in all cases including in a continuous and sometimes least-squares sense when a solution does not exist. This continuity requirement means IK-Geo finds all IK solutions including singular solutions and sometimes least-squares solutions. Robots with three intersecting or parallel axes are solved in closed form. All other commercially available robots have at least one pair of intersecting or parallel axes and are solved by searching over one joint angle. Fully general robots are solved by searching over two joint angles. Search solutions may be converted to a system of three or four polynomials in terms of the end effector pose in the tangent half-angle of one joint. A comparison with IKFast and the MATLAB Robotics Toolbox IK solver demonstrates that IK-Geo has faster computation and can solve more classes of robots.
期刊介绍:
Mechanism and Machine Theory provides a medium of communication between engineers and scientists engaged in research and development within the fields of knowledge embraced by IFToMM, the International Federation for the Promotion of Mechanism and Machine Science, therefore affiliated with IFToMM as its official research journal.
The main topics are:
Design Theory and Methodology;
Haptics and Human-Machine-Interfaces;
Robotics, Mechatronics and Micro-Machines;
Mechanisms, Mechanical Transmissions and Machines;
Kinematics, Dynamics, and Control of Mechanical Systems;
Applications to Bioengineering and Molecular Chemistry