CORBYS

Program

Half Day Workshop on August 11, 2015

Time Table:

08:55 – 09:00 Jan Veneman, Introduction

09:00 – 09:20 Conor Walsh, Next generation soft wearable robots

09:20 – 09:40 Nicola Vitiello, Light-weight wearable robots for lower-limb assistance

09:40 – 10:00 Adrian Leu, Cognitive control architecture to support natural-like walking with the CORBYS gait rehabilitation system

10:00 – 10:20 Carlos Rodriguez Guerrero, Haptic control and machine learning model compensation for novel exoskeleton actuation systems

10:20 – 10:40 Imre Cikajlo, Fully-integrated cognitive controlled walking rehabilitation system: case study in person after a stroke

10:40 – 10:50 Short break

10:50 – 11:10 Etienne Burdet, Detection of motion intention for an intuitive command of lower limb exoskeletons

11:10 – 11:30 Yu Haoyong, Development of Compliant Wearable Robots for Rehabilitation

11:30 – 11:50 Dirk Lefeber, Compliant actuation principles for rehabilitation and assistive robots

11:50 – 12:10 Edwin van Asseldonk, Human-inspired balance strategies in the control of exoskeletons

12:10 – 12:30 Jan Veneman, Exoskeletons supporting balance maintenance

12:30        Closing remarks

 

Topic group 1: Overview of new developments in robotic systems for training and assistance of walking

Nicola Vitiello, Light-weight wearable robots for lower-limb assistance

Ageing population affects society welfare sustainability. The ageing of the population is one of the most critical challenges current industrialized societies will have to face in the next years, and threatens the sustainability of our social welfare. In 40 years from now, nearly 35% of the European population will be older than 60, hence the urgency to provide solutions enabling our ageing society to remain active, creative, productive, and – above all – independent. Among many diseases, gait disorders are common and often devastating companions of ageing, leading to reductions in quality of life and increased mortality.

In the next years, ageing-related lower-limb impairment and disability will lead to a tremendous increase of the number of people needing assistance in their fundamental activities of daily living. In this scenario, people will become increasingly reliant on technology to meet their own needs to live active, fulfilling, and independent lives. Wearable robotics can be an enabling technology for establishing a sustainable welfare.

This presentation will introduce the results achieved by the team of wearable robotics of The BioRobotics Institute of Scuola Superiore Sant’Anna in the last years in the field of wearable robots for lower-limb assistance.

Conor Walsh, Next generation soft wearable robots

Next generation wearable robots will use soft materials such as textiles and elastomers to provide a more conformal, unobtrusive and compliant means to interface to the human body. These robots will augment the capabilities of healthy individuals (e.g. improved walking efficiency, increased grip strength) in addition to assisting patients who suffer from physical or neurological disorders. This talk will focus on two different projects that demonstrate the design, fabrication and control principles required to realize these systems. The first is a soft exosuit that that can apply assistive joint torques to synergistically propel the wearer forward and provide support to minimize loading on the musculoskeletal system. Unlike traditional exoskeletons which contain rigid framing elements, the soft exosuit is worn like clothing, yet can generate significant moments at the ankle and hip to assist with walking. Advantages of the suit over traditional exoskeletons are that the wearer's joints are unconstrained by external rigid structures, and the worn part of the suit is extremely light, which minimizes the suit's unintentional interference with the body's natural biomechanics. The second part of the talk will focus on the preliminary development of a soft robotic glove for hand rehabilitation that consists of a wearable textile with attached elastomeric fluid-powered actuators specially designed to match the natural movements of the fingers and thumb. A component of the research is to develop the knowledge and techniques required to design soft multi-material fluid-powered actuators. Preliminary testing with patients will be presented.

 

Topic group 2: Systems engineering of advanced robotic systems for training and assistance of walking

 

 

Adrian Leu, Cognitive control architecture to support natural-like walking with the CORBYS gait rehabilitation system

The number of mechanical degrees of freedom (DoFs) of rehabilitation robots directly influences the scope of movements that a subject can do when training walking. The most of current gait rehabilitation robots have a limited number of DoFs, which as a consequence limits the movements these robots can make possible. The novel gait rehabilitation system developed within the EU FP7 project CORBYS is the first system which combines all the necessary mechanical DoFs, with a novel and specifically designed 3 DoFs hip joint, needed to enable natural-like walking. Beside the mechanical design of the CORBYS robotic system, the cognitive capabilities integrated within the robot control architecture also support natural-like walking. Among others, these capabilities enable learning of gait by therapist demonstration to generate the reference gait trajectory and adaptation of robotic support according to patient’s state and performance. In this talk, the CORBYS generic cognitive control architecture which enables effective communication between high-level cognitive modules and low-level hard real-time control of complex robotic system is presented. A particular novelty of CORBYS is a software module template to supported effective system integration, which is of high importance in distributed multi-site complex robotic systems development within collaborative research projects such as CORBYS.

Carlos Rodriguez Guerrero, Haptic control and machine learning model compensation for novel exoskeleton actuation systems

Novel exoskeletons are continuously growing in complexity to try to match the inherent complexities of human natural walking and improve physical human robot interaction. In order to improve transparency and performance, exoskeleton designers are are now moving towards machines with several degrees of freedom, compliant actuators, proximally located actuation systems. Although those new designs may serve for improving the overall performance, ergonomics and safety of the exoskeletons, most of them come at a cost with added challenges from the control engineering point of view. Non-linearities, flexibility, backlash and complex geometrical models make clasical controllers and modeling techniques fall short. In this workshop we want to share our experiences on how did we used machine learning to compensate for a system with complex dynamic behavior and how that strategy can be extended to be integrated into a generic robot control architecture.

 

Topic group 3: Actuator designs for human cooperative behavior in robotic systems for training and assistance of walking

Dirk Lefeber, Compliant actuation principles for rehabilitation and assistive robots

Rehabilitation and assistive robots require new approaches for the many drawbacks that come along with conventional electrical actuators, such as high-reflected inertia, high stiffness, low force-to-weight ratio, impact, energy consumption, safety. These new robotic applications can strongly benefit from adaptable compliant actuator technology. Instead of introducing compliance at the control level, this approach is based on the use of inherent adaptable compliance on a purely mechanical level. In this way intrinsic compliant behavior is obtained at all time regardless of the control bandwidth, leading to increased system safety. The added mechanical complexity is easily countered with a range of potential benefits, such as energy efficiency, reduction of power requirements and intrinsic safety. The potential use of adaptable compliant actuators in applications such as prosthetics, rehabilitation and assistive robotics is discussed in view of control strategy, power reduction and energy efficiency. Special focus is put on new combinations of series and parallel arrangements of the elastic elements.

Yu Haoyong, Development of Compliant Wearable Robots for Rehabilitation

We are developing an intelligent compact compliant and modular powered knee-ankle-foot robot for chronic stroke patients to conduct gait rehabilitation. Most exoskeleton robots are built with conventional geared motor actuators which are stiff and bulky. Rehabilitation robots have direct physical interaction with human users, where intrinsic compliance is importance due to safety concern. Compliant actuators based on air muscle are not portable due to the need of compressed air supply. Series elastic actuators (SEA) have been widely adopted for rehab robot design.

However, conventional SEA designs are still not widely used due to the contradictory requirements between intrinsic compliance and force transmission and control capability. We developed a novel compliant actuator that can overcome the limitations of current SEA design and achieve excellent intrinsic compliance, high force control fidelity, and high load transmission and bandwidth. In this talk, we will discuss the design, modeling, control and experimental results of the robotic exoskeleton based on the novel actuator design.

 

Topic group 4: Balance control support in robotic systems for training and assistance of walking

 

Edwin van Asseldonk, Human-inspired balance strategies in the control of exoskeletons

Current commercial exoskeletons provide Spinal Cord Injury subjects with the ability to walk. However when walking with these devices, the patients heavily depend on the use of crutches to maintain stability and balance. The goal of our research is to improve the balancing abilities of exoskeletons by using human inspired cooperative control. Here we are taking two approaches. First, we are incorporating a muscle-reflex model in the control of the exoskeleton. In this presentation, I will present the first results of an evaluation of the robustness to changes in walking speed of this controller in an actuated ankle-foot orthoses (Achilles). Second, we are trying to unravel the human balancing mechanisms during walking by a combination of experimental studies and modeling. This knowledge will be incorporated in the exoskeleton controller. In this presentation, I will present results of a study where we assessed how humans adapt their stepping location to perturbations of different magnitude and direction applied at the pelvis. Finally I will present results of a first explorative study were we assessed how healthy subjects respond to cooperative robotic support in making stepping adjustments to maintain balance.

Jan Veneman, Exoskeletons supporting balance maintenance

Current commercial exoskeletons typically provide weight support or transfer of the swing leg, but rarely address postural control. In rehabilitation this leads to a need of additional balance supporting devices or measures. This talk will discuss several prerequisites for realizing the lower extremity exoskeleton functionality of support to balance control and the avoidance of falls during bipedal activities such as standing and walking. An overview will be given of exoskeleton design requirements, sensor approaches to measuring the balance situation and detection of a loss of balance, control strategies that can be used for balance support, and benchmark design to assess balance performance. Some consideration will be given to applications in neurorehabilitation as well as general support.

 

Topic group 5: Human cooperative control strategies in robotic systems for training and assistance of walking

 

Imre Cikajlo, Fully-integrated cognitive controlled walking rehabilitation system: case study in person after a stroke

Several studies have examined whether the robotic devices may become more effective than the conventional gait training in terms of long term rehabilitation outcomes. The researches have so far reported on promising results and pointed out the main advantages of rehabilitation robots over the strenuous manual physiotherapy. Thus the development of various techniques and control strategies may play an important role, especially when the system has a human voluntary activity in the loop. We have developed a cognitive control for walking rehabilitation system that uses physiological, kinematic and kinetic data assessed during gait. The goal of the cognitive control system is to compute the optimal trajectory for each robotic joint in real-time. During the gait the patient’s voluntary activity is monitored. The goal is to automatically decrease the level of robotic support to the minimum level and the patient gait pattern matches the pattern defined by the physiotherapist. We want to share the initial experience of the first patient with stroke, the promising outcomes that confirm the functionalities of the cognitive control and also meet the expectations of the participating person.

Etienne Burdet, Detection of motion intention for an intuitive command of lower limb exoskeletons

We propose a method to control lower limb exoskeleton steering based on upper body anticipatory behaviour. We use turning anticipation during locomotion to detect the intention to turn based on measured head and pelvis angular orientation. The method is experimentally tested with seven subjects and accurate turning detection is demonstrated. It will be used as an intuitive human-machine interface for controlling lower limb exoskeletons.