Research on dimension coupling of piezoelectric three-component force unit based on sensor assembly error

Abstract

In the process of manufacturing and operation of mechanical equipment, accurate measurement of vector force provides an important basis for real-time control of working conditions and process adjustment to ensure the performance. Piezoelectric three-component force unit can be used to measure three-axis force with the characteristics of high frequency and stiffness, great dynamic response, and resistance to harsh conditions. Piezoelectric dynamometer consisting of four three-component force units can measure six-axis force/torque, which is widely used in vector force measurement. However, because of the limitation of manufacturing capability and assembly process, dimension coupling caused by assembly error of three-component force unit restricts improvement of test accuracy for itself and piezoelectric dynamometer. To reduce dimension coupling caused by displacement and angle assembly error, this article establishes a theoretical model of assembly error of three-component force unit. To achieve that the dimension coupling of threecomponent force unit is less than 3%, stiffness of relevant components is obtained by simulation analysis and experiment, and assembly tolerance range of three-component force unit is proposed. Four three-component force units are assembled to meet assembly tolerance range, and the calibration experiment is performed. The results show that the maximum of dimension coupling is less than 2.5%, which verifies the rationality of assembly tolerance range and further proves the reliability of the theoretical model. The theoretical model of assembly error clarifies the assembly accuracy of three-component force unit to ensure its test accuracy, which can further improve test accuracy of dynamometer. This article will also provide theoretical reference basis for this kind of sensors.

Theoretical and experimental research of six-dimensional force / moment measurement piezoelectric dynamometer

“…Many factors influence the accuracy of piezoelectric sensors such as piezoelectric coupling error, sensors assembly error during calibration, and random gross error. As Jun zhang et al discussed the influence of assembly error of sensor on the test accuracy of three-axis force unit can not be avoided [31]. Therefore, because of the various factors the error in some cases increases, however the measured calibration results of all eight sensors are acceptable (see Table 4), and these sensors are used in the piezoelectric dynamometer.…”

Research on the reliable test range of four-point supported piezoelectric dynamometer

“…Although these methods can improve the reliability of dynamometer, it has disadvantages such as heavy calculation, slow learning speed for complex systems and unclear physical meaning. Zhang et al (2019) established a theoretical model of assembly error of three-component force link to improve the test accuracy of dynamometer. Jia et al (2019) investigated the influence of sheet roughness on the The current issue and full text archive of this journal is available on Emerald Insight at: https://www.emerald.com/insight/0260-2288.htm sensitivity of sensors to improve the precision of dynamometer.…”

Theoretical Investigation of Multidimensional Force/Moment Measurement Dynamometer

“…The designed multi-point measurement model is capable of measuring the three coordinates of force/torque [8]- [9]- [10]- [11]. The model has been designed by providing an upper and lower plate support type assembly to piezoelectric sensors to reduce assembly error [12] and to provide easiness in the installation of load sensors in the model. Thus, it is essential for forcemeasuring devices to precisely measure forces with multi-points locations.…”

“…The piezoelectric technology has been used in this research is based on converting the mechanical energy into an electric voltage or signal. Moreover, when a quartz wafer [15] is packaged as a mono-axial piezoelectric sensor or tri-axial load sensor [16]- [12] as shown in Figure 2. The measuring range of six-axis force/torque sensors is very wide [17] and sensors survive high overload is more than 100 percent of full-scale output.…”