摘要
为了实时估计并控制手术机器人的骨切削深度,首先建立了基于声信号的切削深度估计模型,分析了模型参数的影响因素,并通过验证实验降低不同切削过程和运动参数对模型参数的影响.然后对手术机器人的切削深度控制原理和稳定性进行了分析,提出了一种基于声信号的手术机器人骨切削深度控制方法.利用快速傅里叶变换从切削声中提取刀具旋转频率的一次谐波幅度作为反馈量,根据机器人运动参数在线调整模型参数来估计骨切削深度,进而通过PID(比例-积分-微分)控制器控制手术机器人的骨切削深度.最后,对所提方法进行了实验验证,对估计精度和安全量程进行了实验评估,并与其他方法进行了对比.结果表明,形变和骨密度的变化对所提方法的切削深度控制的影响较小;对于不同固定方式下的猪脊骨,切削深度能保持在可接受的水平;在0~0.5 mm的铣削深度范围内,信号的线性度较高,独立线性率为8.812%F.S.(全量程).所提方法可用于提高手术机器人的骨切削操作的安全性.
This paper aims to estimate and control the bone cutting depth of the surgical robot in real time.Firstly,a cutting depth estimation model based on acoustic signal is established,and the influencing factors of model parameters are analyzed.The influences of different cutting processes and motion parameters on the model parameters are reduced through verification experiments.Then,the cutting depth control principle and the stability of the surgical robot are analyzed,and a bone cutting depth control method for a surgical robot based on acoustic signal is proposed.FFT(fast Fourier transform)is used to extract the first harmonic amplitude of the tool rotation frequency from the cutting acoustic signal as the feedback,and the model parameters are adjusted online according to the robot motion parameters to estimate the bone cutting depth,and then the bone cutting depth of surgical robot is controlled through PID(proportional-integral-differential)controller.Finally,the proposed method is verified by experiments,and the estimation accuracy and the safety range are evaluated experimentally,and compared with other methods.The results show that the changes of the deformation or the bone density have little influence on the cutting depth control by the proposed method.For the pig spine with different fixation methods,the cutting depth can be maintained in an acceptable range.Within the milling depth range of 0∼0.5 mm,the signal linearity is high,and the independent linearity rate can reach 8.812%F.S.(full scale).The proposed method can be used to improve the safety of the bone cutting operation for the surgical robot.
作者
夏光明
代煜
张建勋
贾宾
XIA Guangming;DAI Yu;ZHANG Jianxun;JIA Bin(Institute of Robotics&Automatic Information System,Nankai University,Tianjin 300350,China)
出处
《机器人》
EI
CSCD
北大核心
2021年第1期101-111,共11页
Robot
基金
国家自然科学基金(61773223)
天津市自然科学基金(18JCYBJC18800).
