摘要
为了实现面向牙科患者的个性化成品义齿性能测试,基于6PUS-2HKP空间冗余驱动并联仿生咀嚼机器人,设计了可安装牙模的仿生上颌、下颌结构.针对义齿性能测试对高仿生咀嚼运动的要求,提出了一种基于颞下颌关节(TMJ)运动理论的后牙运循环参数化仿生规划方法.利用拉格朗日方程和虚功原理,推导了冗余驱动咀嚼机器人的动力学方程.分别以颞下颌关节内力2范数最小和驱动力2范数最小为优化目标,建立了基于遗传算法的冗余驱动咀嚼机器人驱动力优化分配数学模型.将食品质构仪获取的仿真食物力-变形关系曲线加载到机器人磨牙上完成了运循环下咀嚼仿真食物实验.结果表明,咀嚼机器人切牙运动轨迹形状、切牙运动速度变化规律、髁突运动形式等均与人类咀嚼运动一致,空载和加载仿真食物两种条件下均可求得合理的驱动力优化分配结果.同时,以仿真实验得到的6组驱动为输入,采用咀嚼机器人样机进行了运循环实验.样机实验和咀嚼仿真食物实验证明了运循环规划方法的仿生性和驱动力优化分配方法的可行性.
In order to achieve individualization of denture performance test for dental patients, the biomimetic maxilla and mandible structures installing a dental model are designed based on a 6PUS-2HKP spatial parallel biomimetic chewing robot with redundant actuation. In order to satisfy requirements of highly biomimetic chewing movements in the denture performance test, a parametric biomimetic planning method for the posterior teeth occlusion masticatory cycle is proposed on the basis of temporomandibular joint (TMJ) motion theories. Combining Lagrangian formulation and virtual work principle, dynamics of the actuation redundant chewing robot is deduced. The mathematics model of driving force optimal distribution of the actuation redundant chewing robot is established by means of genetic algorithm under 2 different optimization goals, i.e. minimal 2-norm of temporomandibular joint forces and minimal 2-norm of driving forces. Applying force-deformation curve of simulation food silicon rubber, which is obtained by food texture analyser, to the molar tooth of the chewing robot, chewing experiments on simulation food under occlusion masticatory cycle are carried out. The experiment results show that incisor trajectory shape, incisor velocity changing rules, and condylar motion forms, and so on, all conform to human chewing movements. Reasonable driving force optimal distribution results can be obtained under conditions with or without simulation food. The occlusion masticatory cycle experiment is carried out on the chewing robot with 6 actuation forces obtained by the simulation as the input. Prototype experiments and chewing experiments on simulation food demonstrate the bio-imitability of the parametric planning method for the posterior teeth occlusion masticatory cycle and the feasibility of the driving force optimal distribution method. © 2017, Science Press. All right reserved.
出处
《机器人》
EI
CSCD
北大核心
2017年第1期70-80,共11页
Robot
基金
国家自然科学基金(51575078)
