Aiming at the problem that it is difficult to generate the dynamic decoupling equation of the parallel six-dimensional acceleration sensing mechanism,two typical parallel six-dimensional acceleration sensing mechanism...Aiming at the problem that it is difficult to generate the dynamic decoupling equation of the parallel six-dimensional acceleration sensing mechanism,two typical parallel six-dimensional acceleration sensing mechanisms are taken as examples.By analyzing the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,a new method for establishing the dynamic equation of the sensing mechanism is proposed.Firstly,based on the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,the expression of the branch rod length is obtained.The inherent constraint relationship between the branches is excavated and the branch coordination closed chain of the“12-6”configuration is constructed.The output coordination equation of the sensing mechanism is successfully derived.Secondly,the dynamic equations of“12-4”and“12-6”configurations are constructed by the Newton-Euler method,and the forward decoupling equations of the two configurations are solved by combining the dynamic equations and the output coordination equations.Finally,the virtual prototype experiment is carried out,and the maximum reference errors of the forward decoupling equations of the two configuration sensing mechanisms are 4.23%and 6.53%,respectively.The results show that the proposed method is effective and feasible,and meets the real-time requirements.展开更多
文摘目的观察补肾活血协定方治疗膝关节骨性关节炎(knee osteoarthritis,KOA)(肾虚血瘀证)的疗效。方法选取2018年2月—2020年2月医院收治的KOA患者186例,按照随机数字表法将患者分为对照组(n=93例)和观察组(n=93例)。对照组给予依托考昔片口服,观察组在对照组基础上加用补肾活血协定方口服,连续治疗2个月。分别以疼痛视觉模拟评分法(visual analogue scale,VAS)、美国特种外科医院量表(hospital for special surgery scores,HSS)评价膝关节疼痛程度与膝关节功能,用膝关节高频超声检查软骨厚度、滑膜厚度,检测关节液中肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、Toll样受体-4(Toll-like receptor 4,TLR-4)、P物质(Substance P,SP)含量及血清中脂联素(adiponectin,APN)、低氧诱导因子1α(hypoxic induction factor-1α,HIF-1α)水平,对比两组治疗效果。结果:观察组的有效率93.55%(87/93),与对照组82.79%(77/93)的有效率比较,以观察组显著升高(χ2=5.155,P<0.05);两组患者的VAS评分在治疗治疗2周、治疗4周后均降低,HSS评分在治疗2周、治疗4周后均升高,以观察组VAS评分显著高于对照组,HSS评分显著高于对照组(P<0.05);治疗后,两组在增加关节软骨厚度、降低滑膜厚度等方面均具有一定效果,以观察组软骨厚度增加程度、滑膜厚度降低程度更明显(P<0.05);观察组患者经治疗后关节液中TNF-α、TLR-4、P物质水平均显著低于对照组(P<0.05);血清APN水平显著升高,HIF-1α水平显著降低(P<0.05)。结论补肾活血协定方利于减轻膝骨性关节炎患者的关节疼痛,提高膝关节功能,其机制可能与调节关节液、血清中相关因子水平以减轻滑膜炎症、调节软骨代谢有关,值得进行临床推广。
基金supported in part by the National Natural Science Foundation of China(No.51405237)。
文摘Aiming at the problem that it is difficult to generate the dynamic decoupling equation of the parallel six-dimensional acceleration sensing mechanism,two typical parallel six-dimensional acceleration sensing mechanisms are taken as examples.By analyzing the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,a new method for establishing the dynamic equation of the sensing mechanism is proposed.Firstly,based on the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,the expression of the branch rod length is obtained.The inherent constraint relationship between the branches is excavated and the branch coordination closed chain of the“12-6”configuration is constructed.The output coordination equation of the sensing mechanism is successfully derived.Secondly,the dynamic equations of“12-4”and“12-6”configurations are constructed by the Newton-Euler method,and the forward decoupling equations of the two configurations are solved by combining the dynamic equations and the output coordination equations.Finally,the virtual prototype experiment is carried out,and the maximum reference errors of the forward decoupling equations of the two configuration sensing mechanisms are 4.23%and 6.53%,respectively.The results show that the proposed method is effective and feasible,and meets the real-time requirements.
