基于十字梁结构的六维力/力矩传感器全方位机械过载保护研究

Research on Omnidirectional Mechanical Overload Protection of the Cross Beam Type Six⁃Axis Force/Torque Sensor

六维力/力矩传感器是空间机械臂智能化的核心关键部件,随航天器发射进入太空的过程中会面临剧烈的振动与冲击。缺乏过载保护的六维力/力矩传感器可能遭到破坏而失去测量能力。针对这一问题,以十字梁结构六维力/力矩传感器为研究对象,对其受力变形特征进行理论和仿真分析,确定了各维力过载保护的原理。进而提出一种勾合式全方位机械过载保护机构,利用间隙限位实现对传感器全方位保护。间隙限位不仅能够保证传感器在过载时不被损坏,而且不会影响其正常的力测量功能。通过理论分析确定了间隙大小;并通过数值仿真验证了该结构的过载保护能力,结果表明该结构可以在不影响六维力/力矩传感器正常测量的情况下,可以分别在F_(x)/F_(y)、F_(z)、M_(x)/M_(y)、M_(z)方向提高20、20、13、20倍的过载能力。

The Six⁃axis force/torque sensor is the critical component in the intelligentizing of space manipulator.In the process of launching into space with the spacecraft,the sensor will face severe vibration and impact.As a result,the structure of the sensor will be destroyed and the capability of force measurement will be lost without overload protection.To solve this problem,the cross beam type six⁃axis force/torque sensor is taken as the research object to carry on the theoretical and simulation analysis to the deformation charac⁃teristics,and determine the principle of overload protection of each dimension force.Furthermore,a hook type omnidirectional mechani⁃cal overload protection mechanism is proposed,which realizes the omnidirectional protection of the sensor by using the gap limit.The gap limit ensures that the sensor will not be damaged when it is overloaded,while not affectting the normal force measurement function.The size of the gap limit is determined through theoretical analysis and the numerical simulation is carried out to verify the overload pro⁃tection capability.The simulation results show that the overload protection capability of the structure can be improved by 20,20,13,20 times in F_(x)/F_(y),F_(z),M_(x)/M_(y),M_(z)respectively without affecting the normal force measurement of the six⁃axis force/torque sensor.