Six-dimensional force sensors can simultaneously detect the full force information in three-dimensional space, i.e. three-dimensional force information (fx, fy, fz) and three-dimensional moment information (mx, my, mz), mainly used in force and moment position control occasions, such as contour tracking, precision assembly, two-handed coordination, six-dimensional force information detection in test systems, etc.

The measurement accuracy of the sensor is one of the most important performance indicators to evaluate the sensor, and its errors include random and systematic errors. For the six-dimensional force sensor, the random error is mainly caused by the internal signal processing circuit, quantization error, external interference and other factors; system error is mainly determined by the calibration system calibration accuracy, six-dimensional force sensor due to the complexity of its own mechanical structure, as well as the sensor in the manufacturing, strain gauge and other processing errors, the sensor input and output channels exist between each other Due to the complexity of the mechanical structure of the transducer and the errors in the manufacturing and strain gage application processes, the input and output channels of the transducer are coupled to each other. The design of the sensor calibration device and the calibration method are therefore of paramount importance, as the calibration accuracy will directly affect the accuracy of the measurement in use.

The calibration of a six-dimensional force transducer is based on the application of independent forces/moments in a spatial coordinate system or multiple forces/moments that are linearly independent, and reading the output of the six-dimensional force transducer in various states of calibration to calculate the decoupling matrix. The calibration of six-dimensional force sensors is divided into static calibration and dynamic calibration according to the actual application requirements. Static calibration is mainly used to check the static performance indicators of the sensors, such as static sensitivity, non-linearity, return difference, repeatability, etc.; dynamic calibration is mainly used to check the dynamic characteristics of the sensors, such as dynamic sensitivity, frequency response and inherent frequency, etc.

The current static calibration of the six-dimensional force transducer used by the loading method mainly has a force ring type and weight type two. Among them, the force ring type loading using the top bar method, by the force ring read out the value of the loading force, this kind of loading allows a large loading force, but the reading accuracy is low, high precision force ring is expensive. Weight-based calibration uses grade weights to provide a standard loading force and directly uses the grade weights as a reference, with higher force accuracy, and is more commonly used in the calibration of medium-range and small-range six-dimensional force transducers.

The present invention discloses a comparative six-dimensional force sensor calibration device, including a frame, a loading device, a sensor fixing device and a loading rod, the loading device and the sensor fixing device are located on the frame, the loading device is located above the sensor fixing device, the sensor to be measured is fixed on the sensor fixing device, the loading rod is fixedly connected to the sensor to be measured, the loading device realizes the loading of the sensor to be measured in all directions by means of the loading rod). The loading device is connected to the sensor to be measured by the loading rod. This device, because the loading device is in three positions, the position of the loading force is located on the same circumference, so when loading in each direction of the sensor to be measured, the moment length is equal, which improves the calibration accuracy. This calibration method allows the calibration of six directions of the sensor to be completed by simply adjusting the position of the loading device and the sensor fixing device during calibration, improving the efficiency of the calibration.