Orientation Parameters Compensation Method of Distributed Measurement Systems

Distributed measurement systems based on the principle of angle intersection measurements, represented by workshop measurement positioning system (wMPS), are widely used in industrial manufacturing sites due to their high accuracy, scalable range, and multitarget parallel measurement capabilities. However, the change in the base station’s attitude and position by structural creepage or external disturbance makes networking difficult and reduces system measurement accuracy. During measurement tasks, the orientation space and the number of constraints are hard to guarantee due to the light blockage caused by large equipment entering the orientation area. Traditional orientation methods based on a reference ruler or control points are no longer feasible under the circumstances. In this article, we propose an orientation parameters compensation method for distributed measurement systems. We introduce a high-precision inclinometer and a photoelectric autocollimator with the base station of a distributed measurement system to establish an attitude measurement system. Orientation parameters compensation is completed using the attitude measurement system, with only one external length constraint required for position parameter updates. Simulation and experimental results reveal that the angle accuracy of the attitude measurement system is less than 2″, and the ruler length measurement error of the distributed measurement system is within ±0.15 mm after compensation, indicating that accuracy has been recovered to the levels of initial orientation. Our proposed method greatly reduces the number of external constraints required and unknown parameters, avoids limitations by space and constraint quantity, and improves orientation efficiency and adaptability in long-term measurement tasks.