Learning dynamic motor skills for terrestrial locomotion

The use of Deep Reinforcement Learning (DRL) has received significantly increased attention from researchers within the robotics field following the success of AlphaGo, which demonstrated the superhuman capabilities of deep reinforcement algorithms in terms of solving complex tasks by beating professional GO players. Since then, an increasing number of researchers have investigated the potential of using DRL to solve complex high-dimensional robotic tasks, such as legged locomotion, arm manipulation, and grasping, which are difficult tasks to solve using conventional optimization approaches. Understanding and recreating various modes of terrestrial locomotion has been of long-standing interest to roboticists. A large variety of applications, such as rescue missions, disaster responses and science expeditions, strongly demand mobility and versatility in legged locomotion to enable task completion. In order to create useful physical robots, it is necessary to design controllers to synthesize the complex locomotion behaviours observed in humans and other animals. In the past, legged locomotion was mainly achieved via analytical engineering approaches. However, conventional analytical approaches have their limitations, as they require relatively large amounts of human effort and knowledge. Machine learning approaches, such as DRL, require less human effort compared to analytical approaches. The project conducted for this thesis explores the feasibility of using DRL to acquire control policies comparable to, or better than, those acquired through analytical approaches while requiring less human effort. In this doctoral thesis, we developed a Multi-Expert Learning Architecture (MELA) that uses DRL to learn multi-skill control policies capable of synthesizing a diverse set of dynamic locomotion behaviours for legged robots. We first proposed a novel DRL framework for the locomotion of humanoid robots. The proposed learning framework is capable of acquiring robust and dynamic motor skills for humanoids, including balancing, walking, standing-up fall recovery. We subsequently improved upon the learning framework and design a novel multi-expert learning architecture that is capable of fusing multiple motor skills together in a seamless fashion and ultimately deploy this framework on a real quadrupedal robot. The successful deployment of learned control policies on a real quadrupedal robot demonstrates the feasibility of using an Artificial Intelligence (AI) based approach for real robot motion control

Design and control of a teleoperation system for humanoid walking

Master'sMASTER OF ENGINEERIN

Case Study of Physiotherapy Treatment of a Patient with Bilateral Achilles Tendon Prolongation after Spastic Biparesis of Neuroinfectious Aetiology

FyzioterapieFaculty of Physical Education and SportFakulta tělesné výchovy a sport

Reimagining Robotic Walkers For Real-World Outdoor Play Environments With Insights From Legged Robots: A Scoping Review

PURPOSE For children with mobility impairments, without cognitive delays, who want to participate in outdoor activities, existing assistive technology (AT) to support their needs is limited. In this review, we investigate the control and design of a selection of robotic walkers while exploring a selection of legged robots to develop solutions that address this gap in robotic AT. METHOD We performed a comprehensive literature search from four main databases: PubMed, Google Scholar, Scopus, and IEEE Xplore. The keywords used in the search were the following: “walker”, “rollator”, “smart walker”, “robotic walker”, “robotic rollator”. Studies were required to discuss the control or design of robotic walkers to be considered. A total of 159 papers were analyzed. RESULTS From the 159 papers, 127 were excluded since they failed to meet our inclusion criteria. The total number of papers analyzed included publications that utilized the same device, therefore we classified the remaining 32 studies into groups based on the type of robotic walker used. This paper reviewed 15 different types of robotic walkers. CONCLUSIONS The ability of many-legged robots to negotiate and transition between a range of unstructured substrates suggests several avenues of future consideration whose pursuit could benefit robotic AT, particularly regarding the present limitations of wheeled paediatric robotic walkers for children’s daily outside use. For more information: Kod*lab (link to kodlab.seas.upenn.edu

The effect of unsupportive and supportive footwear on children’s multi-segment foot dynamics during gait

Footwear is necessary for children’s foot comfort and protection. Despite the popularity of flip-flop (thongs) footwear among children, strong clinical opinion endures of the potential deleterious effect this footwear may have on developing feet. On the contrary, thongs may be beneficial for children’s developing feet due to the footwear’s flexible and unrestrictive nature, as children who mature within habitually barefoot communities are observed to develop stronger and healthier feet. This thesis considers the developing nature of human ambulation and the physiological basis for children’s foot maturation. It then explores the effect of thong footwear on childrens barefoot dynamics with comparisons to traditionally advocated supportive footwear. Foot compensations were observed when thongs were worn while walking and to a lesser extent while jogging. Greater ankle dorsiflexion and reduced hallux dorsiflexion suggests a mechanism to retain the thong. Greater midfoot plantarflexion indicates a gripping action to sustain the thong. Barefoot motions were unaffected by thongs during the sidestep. The midfoot splinting effect of supportive shoes was reinforced while walking, jogging and sidestepping. Thongs had a minimal effect on barefoot dynamics, while supportive shoes limited midfoot power generation with a corresponding increase in ankle power generation. Overall findings suggest that foot motion when wearing thongs may be more replicable of barefoot motion than originally believed. In terms of foot arch development, thongs may be more beneficial than supportive shoes, due to the minimal alterations to barefoot motions when they are worn. The reported midfoot plantarflexion required to grip the thong may be beneficial to children’s foot arch strengthening and overall foot development. While supportive shoes have the necessary protective features, they have been shown to inhibit midfoot and hallux motions with a compensatory increase in ankle motions

Analysis of the backpack loading efects on the human gait

Gait is a simple activity of daily life and one of the main abilities of the human being. Often during leisure, labour and sports activities, loads are carried over (e.g. backpack) during gait. These circumstantial loads can generate instability and increase biomechanicalstress over the human tissues and systems, especially on the locomotor, balance and postural regulation systems. According to Wearing (2006), subjects that carry a transitory or intermittent load will be able to find relatively efficient solutions to compensate its effects.info:eu-repo/semantics/publishedVersio