A Normal Sensor Calibration Method Based on an Extended Kalman Filter for Robotic Drilling.

Dongdong Chen,Ying Cai,Haiyang Tang,Peijiang Yuan,Tianmiao Wang

doi:10.3390/s18103485

Abstract

To enhance the perpendicularity accuracy in the robotic drilling system, a normal sensor calibration method is proposed to identify the errors of the zero point and laser beam direction of laser displacement sensors simultaneously. The procedure of normal adjustment of the robotic drilling system is introduced firstly. Next the measurement model of the zero point and laser beam direction on a datum plane is constructed based on the principle of the distance measurement for laser displacement sensors. An extended Kalman filter algorithm is used to identify the sensor errors. Then the surface normal measurement and attitude adjustments are presented to ensure that the axis of the drill bit coincides with the normal at drilling point. Finally, simulations are conducted to study the performance of the proposed calibration method and experiments are carried out on a robotic drilling system. The simulation and experimental results show that the perpendicularity of the hole is within 0.2°. They also demonstrate that the proposed calibration method has high accuracy of parameter identification and lays a basis for high-precision perpendicularity accuracy of drilling in the robotic drilling system.

Highlights

IntroductionMechanical connections are the main type of connection between the components of the aircraft
In aircraft assembly, mechanical connections are the main type of connection between the components of the aircraft
The perpendicularity of the hole is an important factor affecting the quality of the hole, which is mainly determined by the angle between the normal at the drilling point and the axis of the drill bit

Summary

Introduction

Mechanical connections are the main type of connection between the components of the aircraft. If the angle between the axis of the drill bit and the normal at drilling point is larger, the diameter of the hole becomes larger, the cutting force in the drilling process increases, the cutting heat increases, the burr height increases, and the life of the tool decreases [6]. It will affect the connection quality and fatigue strength of aircraft components [7]. Laser displacement sensors are commonly used non-contact measurement sensors, which have many advantages such as high-precision, low power

Methods

Results

Conclusion