This paper presents an approach to haptically controlling an industrial robot without using any external sensors for human-robot collaborative assembly. The sensorless haptic control approach is enabled by the dynamic models of the robot where only joint angles and joint torques are measurable. Accurate dynamic models of the robot in the presliding and sliding regimes are developed to estimate the external forces/torques, where the friction model is also explored. The estimated external force applied to the robot by an operator is converted to the reference position and speed of the robot by an admittance controller. In this research, adaptive admittance control is adopted to support human-robot collaborative assembly, naturally and easily, with accurate positioning and control for smooth movement. Moreover, torque-based commands are used to control the robot’s assembly operations. Finally, the proposed approach is validated by a case study on assisting an operator during the collaborative assembly of a car engine.

本文提出了一种在不使用任何外部传感器进行人机协作组装的情况下以触觉方式控制工业机器人的方法。无传感器触觉控制方法由仅可测量关节角度和关节扭矩的机器人动态模型实现。开发了机器人在预滑动和滑动状态下的精确动态模型，以估计外力/扭矩，并在其中探索了摩擦模型。由操作员施加给机器人的估计外力由导纳控制器转换为机器人的参考位置和速度。在这项研究中，采用自适应导纳控制来自然轻松地支持人机协作装配，并通过精确的定位和控制来实现平稳的运动。此外，基于扭矩的命令用于控制机器人的组装操作。最后，通过在汽车发动机的协同装配过程中协助操作员的案例研究验证了所提出的方法。