Measurement Error of 3D Shape and Position of Multi-core Optical Fiber for Precision Operation of Continuum Robots
Aiming at the problem of high-precision measurement of 3D shape and position of continuum robot when it operates precisely in a complex enclosed space,an error analysis and correction method based on multi-core optical fiber deformation sensing equation and 3D shape reconstruction algorithm is proposed.Based on the structural characteristics of multi-core optical fiber sensing and the principle of 3D spatial geometric transformation,the key equations and algorithms for 3D shape and position measurement of multi-core optical fiber are deduced and established.Using the key model and algorithm-driven method,the influence of key parameter error of the multi-core fiber,signal demodulation error,sensing equation and reconstruction algorithm error,and ambient temperature change on the measurement accuracy is systematically analyzed,and the main error sources and their quantitative influence degrees are determined.Through error traceability,the calibration and error correction methods of key parameters of the measurement system are established.A seven-core optical fiber measurement experimental device is constructed,and the effectiveness of the method is verified by experiments.The results show that the proposed method can realize the traceability,quantitative analysis and correction of systematic measurement error,effectively improve the 3D shape and position measurement accuracy of multi-core optical fiber sensing system,and have application value and prospect in the field of precision measurement of continuum robots.