Torque sensor for force frequency characteristic detection of piezoelectric material

Abstract

The invention relates to a torque sensor for force frequency characteristic detection of a piezoelectric material, which comprises strain beams, an inner spoke and an outer spoke, the inner spoke and the outer spoke are respectively used as an input unit or an output unit of the torque sensor, a plurality of strain beams are arranged between the inner spoke and the outer spoke, through holes are formed in the strain beams, and the through holes are communicated with the strain beams, the strain cross beam is provided with a beam groove corresponding to the through hole, and an opening of the beam groove is provided with a piezoelectric film. Two times of stress amplification are carried out on the strain cross beam, the first time of stress amplification is realized by forming the through hole in the strain cross beam, and the second time of stress amplification is carried out by forming the beam groove in one side or two sides of the through hole and forming a beam film structure with the piezoelectric film, so that the sensitivity of the sensor can be greatly improved; when the moment is detected, the piezoelectric film located at the two-time amplification part can generate frequency change while being stressed, the moment is detected by testing the frequency, and the sensor has the advantages of being short in response time, high in measurement precision, high in stability and the like.

Description

technical field [0001] The invention relates to the technical field of detection of force-frequency characteristics of piezoelectric materials, in particular to a torque sensor used for detection of force-frequency characteristics of piezoelectric materials. Background technique [0002] In recent years, the frequency of use of robotic arms in various fields such as industry, logistics, and service industries has continued to increase. At the same time, scenarios where robotic arms and humans work simultaneously (such as manual teaching, rehabilitation robots, etc.) have also increased significantly. To complete the direct contact between the human and the robotic arm requires more dexterous movement and excellent force control performance of the robotic arm, which is usually achieved through a compliant control algorithm. [0003] The key problem of compliance control algorithm is to obtain the contact force information of the manipulator. For a tandem robot composed of a...

AI Technical Summary

Problems solved by technology

For example, the patent document CN105965504A describes a device for detecting torque, which uses a four-beam spoke structure combined with metal strain gauges as a sensitive unit, and uses a method of interleaving the strain gauges to detect torque. A total of 8 strain gauges are used, of which four strain gauges form a bridge circuit in a group. While measuring the resistance value of the strain gauges, temperature compensation is realized through a special bridge circuit, and the installation of the other four strain gauges It is to provide another set of bridge circuits as a measurement comparison reference while ensuring the symmetry of the overall structure and reduce measurement errors. The design of this traditional sensor makes the number of sensitive units of the sensor too large, and the overall stiffness of the sensor will be reduced. At the same time, the use of strain gauges as the sensing unit has the disadvantages of low precision, slow measurement speed, and low dynamic response

[0006] The patent document CN106737773A proposes a sensor with high stiffness, which uses a novel structural design to improve the stiffness of the overall structure and prevent axial and radial forces from interfering with the sensor, but the sensitive unit still uses 8 metal strain gauges, and Sensing unit is not designed to improve sensitivity

Images