Robot calibration is the process of enhancing the accuracy of a robot by modifying its control software. This book provides a comprehensive treatment of the theory and implementation of robot calibration using computer vision technology. It is the only book to cover the entire process of vision-based robot calibration, including kinematic modeling, camera calibration, pose measurement, error parameter identification, and compensation.
The book starts with an overview of available techniques for robot calibration, with an emphasis on vision-based techniques. It then describes various robot-camera systems. Since cameras are used as major measuring devices, camera calibration techniques are reviewed.
Camera-Aided Robot Calibration studies the properties of kinematic modeling techniques that are suitable for robot calibration. It summarizes the well-known Denavit-Hartenberg (D-H) modeling convention and indicates the drawbacks of the D-H model for robot calibration. The book develops the Complete and Parametrically Continuous (CPC) model and the modified CPC model, that overcome the D-H model singularities. The error models based on these robot kinematic modeling conventions are presented.
No other book available addresses the important, practical issue of hand/eye calibration. This book summarizes current research developments and demonstrates the pros and cons of various approaches in this area. The book discusses in detail the final stage of robot calibration - accuracy compensation - using the identified kinematic error parameters. It offers accuracy compensation algorithms, including the intuitive task-point redefinition and inverse-Jacobian algorithms and more advanced algorithms based on optimal control theory, which are particularly attractive for highly redundant manipulators.
Camera-Aided Robot Calibration defines performance indices that are designed for off-line, optimal selection of measurement configurations. It then describes three approaches: closed-form, gradient-based, and statistical optimization. The included case study presents experimental results that were obtained by calibrating common industrial robots. Different stages of operation are detailed, illustrating the applicability of the suggested techniques for robot calibration. Appendices provide readers with preliminary materials for easier comprehension of the subject matter. Camera-Aided Robot Calibration is a must-have reference for researchers and practicing engineers-the only one with all the information!
Motivation
Historical Perspective
Camera Calibration
Introduction
Camera Models
Tsai's RAC-Based Camera Calibration Algorithm
A Fast RAC-Based Algorithm
Optical Axis Perpendicular to the Calibration Board
Nonlinear Least-Squares Approach
Estimation of the Ratio of Scale Factors
Estimation of the Image Center
Perspective Projection Distortion of Circular Calibration Points
Simulation and Experimental Results
Summary and References
Kinematic Modeling for Robot Calibration
Introduction
Basic Concepts in Kinematics
The Denavit-Hartenberg Model and Its Modification
The CPC Model and the MCPC Model
Relationship Between the CPC Model and Other Kinematic Models
Parametric Continuity - General Treatment
Singularities of the MCPC Model
Discussions and References
Pose Measurement with Cameras
Introduction
System Configurations
Pose Measurement with Moving Cameras
Identification of the Relationship between Robot End-Effector and Camera
Summary and References
Error-Model-Based Kinematic Identification
Introduction
Differential Transformations
Finite Difference Approximation to Kinematic Error Models
Generic Linearized Kinematic Error Models
The D-H Error Model
The CPC Error Model
The MCPC Error Model
Summary and References
Kinematic Identification: Linear Solution Approaches
Introduction
Problem Formulation and a Solution Strategy
A Hybrid Linear Solution for an All-Revolute Robot
An All-Recursive Linear Solution Approach for General Serial Manipulators
Extension of the Hybrid Linear Solution Method to General Serial Robots
Numerical Studies
Summary and References
Simultaneous Calibration of a Robot and a Hand-Mounted Camera
Introduction
Kinematic Model, Cost Function, and Solution Strategy
The Identification Jacobian
Implementation Issues
Extension to Stereo-Camera Case
Summary and References
Robotic Hand/Eye Calibration
Introduction
Review of Quaternion Algebra
A Linear Solution
A Nonlinear Iterative Solution
Simulation Results
Discussion and References
Robotic Base Calibration
Introduction
Problem Statement
Estimation of the Base Orientation
Estimation of the Base Position
Experimental Results
Summary and References
Simultaneous Calibration of Robotic Base and Tool
Introduction
Problem Statement
A Linear Solution
Simulation Studies
Summary and References
Robot Accuracy Compensation
Introduction
Workspace-Mapping Method
Model-Based Pose-Redefinition Algorithm
Gradient-Based Algorithms
Summary and References
Selection of Robot Measurement Configurations
Introduction
Problem Statement
Two Simple Search Algorithms
Configuration Selection by Simulated Annealing Algorithms
Summary and References
Practical Considerations and Case Studies
Introduction
Practical Considerations
Calibration of the PUMA Arm
Calibration of a SCARA Arm
Summary and References
References
Appendices
Summary of Basic Concepts in Matrix Theory
Least Squares Techniques
Sensitivity Analysis
Index
Biography
Zhuang, Hangi | Roth, Zvi S.
"…addresses both the concepts and implementation of robot calibration using computer vision technology…well written and clearly presented…figures associated with the text not only help in understanding the mathematics, but the photographs assist in visualising actual calibration systems."
--Industrial Robot: An International Journal, Vol. 27, No. 6