为了保证机器人研磨的控制精度，提高研磨工件的加工质量，研制了一种基于浮动平台的机器人研磨系统，提出线性自抗扰控制的恒力研磨策略.所研制的机器人浮动平台研磨系统主要包含机器人、力反馈传感器、研磨系统、浮动平台机构，以研磨系统为研究对象，建立机器人末端工件与磨盘接触的磨削力模型.基于此非线性机器人磨削模型设计扩张状态观测器，分析线性自抗扰控制算法的闭环稳定性，提出线性自抗扰恒力研磨控制律，并为验证所提出的方法进行了实验分析.研究结果表明：线性自抗扰控制研磨算法能实现有效的恒力研磨控制；与比例积分微分（PID）控制相比，线性自抗扰控制能显著地减少机器人稳定磨削过程中的力波动，大大降低了研磨工件的表面粗糙度.
In order to keep the control accuracy of robotic grinding and improve quality of grinding workpiece, a robotic grinding system based on the floating platform is developed and a constant force grinding strategy of linear active disturbance rejection control (LADRC) is proposed.The robotic floating grinding system mainly includes robots, force feedback sensors, grinding system and floating platform mechanism.Taking the robotic grinding system as the research object, grinding contacting force model between the workpiece at the end of the robot and the grinding disc is established.According to the nonlinear robot grinding model, the extended state observer is designed. The closed-loop stability of LADRC is analyzed, and the corresponding grinding experiments are designed to verify the feasibility of LADRC algorithm. Finally experiments and analyses show that LADRC can realize an effective robotic constant force control for disk grinding.Comparing with proportion integration differentiation (PID) control, LADRC can significantly reduce the force fluctuation during the grinding process and greatly decrease the surface roughness of abrasive workpiece.
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