Novel Bio-Inspired 'Smart' Joint for Prosthetics and Robotics Lower Limbs

目前，仅在英国，每年就有超过9万例新的膝关节置换术和截肢手术。这相当于大约每六分钟发生一次。目前，英国每年有5 - 6000例主要肢体截肢手术，其中创伤约占55%。下肢截肢对日常生活活动有深远的影响，并不是所有的截肢者都能忍受或使用假肢。因此，为了增强患者的日常活动，假肢的舒适性和适应性是至关重要的。人工膝关节是一种重要的医疗设备，它使许多人能够保持行走和跑步的功能。在努力实现这一目标的过程中，研究人员一再错过了软组织（韧带）和结构（骨骼）在类人运动中的相关性所起的关键作用。生物关节通过整合高一致性、紧凑性和低摩擦来展示多功能。通过在概念阶段将功能分离包括在内，这些功能在设计功能性和健壮性关节时至关重要。尽管在进行人体运动时所涉及的确切含义和机制仍然知之甚少，但最近对韧带力学和膝关节受压分析的工程研究已经产生了一些模型和模拟，这些模型和模拟揭示了人类膝关节特征的一些可能的作用。因此，我们认为将功能分离到假肢关节的设计过程中对于促进设计优化至关重要。研究人员正积极致力于开发可穿戴设备，包括越来越多嵌入控制和电子子系统的假肢，使其更加自主和“智能”。另一方面，空间和功率的限制意味着假肢关节（用于机器人或假肢）必须在刚度、强度、摩擦、机械优势、间隙和耐力等方面高度优化机械性能。目前人造下肢的设计趋势，从机器人关节到下肢截肢者的假肢，都倾向于使用工程关节，这些关节通常由包含铰链销和滚珠轴承的销钉关节组成。特殊的假体膝关节（多中心）包含四杆机构，以产生一个移动的旋转中心，就像人类的膝盖一样。假体膝关节的控制主要有两大类——微处理器控制（使用电子装置，评估并进行内部调整以控制运动）和机械控制（使用机械铰链，由机构自动控制）。这项工作的主要目的是进一步发展假肢设计的最新技术，并为经股骨（膝盖以上）截肢者和类人机器人提供下肢机械肢，这些机器人与人工设备及其运动用途有关，包括行走、爬楼梯、下蹲和稳定。这项研究将结合三个领域之间的关系：下肢机器人的技术进步，全膝关节置换术的膝关节植入设计，以及“智能”假肢的出现。在这个为期两年的项目中，我们将研究一种新型仿生假体关节的可行性和发展，这种假体关节将利用人类膝关节的关键和有益特征。这项研究将通过采用一种渐进的自下而上的方法来设计和测试仿生“智能”关节。在2016年b里约热内卢残奥会的一名铁人三项金牌得主的帮助下，将对新型仿生关节与工业合作伙伴提供的现有假肢之间的人体性能（能量消耗和步态效率）进行比较调查。

At present there are over 90,000 new cases of knee replacements and leg amputations every year in the UK alone. This is equivalent to approximately one every six minutes. Currently between 5 - 6,000 major limb amputations are performed in the UK each year and trauma accounts for approximately 55% of them. Lower limb amputation has a profound effect on activities of daily living and not all amputees are able to tolerate or use a prosthesis. Therefore, it is essential that the prosthesis is comfortable and adapted to be used by patients in order to enhance their daily activities. Artificial knee joints are important medical devices that enable many people to maintain walking and running functions. In working towards this target, researchers have repeatedly missed the key role held by the correlation between the soft tissues (ligaments) and the structure (bones) in human-like locomotion. Biological joints demonstrate multi-functionality by integrating high conformity, compactness and low friction. These functions are crucial when designing a functional and robust joint by including this separation of functions at the conceptual stage.Though there is still little known about the exact implications and mechanisms involved while performing human movement, recent engineering research into the mechanics of the ligaments and the analysis of the knee joint in compression has produced models and simulations that have shed light on some of the possible roles of the human knee features. Therefore, we believe that this separation of functions into the design process of prosthetic joint is essential to facilitate design optimisation.Researchers are actively engaged in developing wearable devices including prosthetics that are increasingly embedding control and electronics sub-systems making them more autonomous and 'smarter'. On the other hand, limitations on space and power mean that artificial limb joints (for robots or prosthetics) must be highly optimised for mechanical performance in areas such as stiffness, strength, friction, mechanical advantage, backlash and endurance.Current trends in the design of artificial lower limbs, ranging from robotic articulations to prostheses for lower limb amputees, favour the utilisation of engineered joints, which typically are composed of a pin joint containing a hinge-pin and ball bearings. Particular prosthetic knee joints (polycentric) contain four-bar mechanisms in order to produce a moving centre of rotation as is the case with the human knee. There are two main categories of control for prosthetic knee joints - microprocessor control (use of an electronic unit, evaluating and making internal adjustments to control the motion) and mechanical control (use of a mechanical hinge, automatically controlled by the mechanism).The main purpose of this work is to further the state-of-the-art in prosthetics design and lower robotic limbs for transfemoral (above knee) amputees and humanoids robots in areas relevant to artificial devices and their uses for locomotion including walking, climbing stairs, squatting and also stability. This research will combine the relationship between three areas: the technological advancements of lower robotic limbs, knee implant design for total knee replacement, and the emergence of 'smart' prosthetics.In this two-year programme, we will investigate the feasibility and development of a novel bio-inspired prosthetic joint that will exploit the key and beneficial features of human knee joint. This research will be achieved by featuring a progressive bottom up approach towards the design and test of the bio-inspired 'smart' joint. A comparative investigation with respect to human performance (energy consumption and gait efficiency) between the novel bio-inspired joint against current prosthetics provided by the industrial partners will be undertaken with the contribution of a para-triathlete gold medallist in the Rio Paralympics 2016.