Agile and Dexterous Robotics Lab
Acceleration Based Transparency Control
I will present a novel approach to interaction control of robotic devices using acceleration measurement and model based control. A key insight is that the recent progress of affordable, lightweight IMUs – which provide very clean, low latency acceleration measurements – enables us to use these signals in closed loop controllers in robotic applications. Using acceleration measurements in controllers allows us to rethink classical approaches to interaction control for exoskeletons, haptics and virtual avatars and with this remove limits in how much transparency we can achieve in such applications. I will show that with our acceleration based model based control approaches we can in principle get rid of any lag between a human operator and an exoskeleton and this leads to fully transparent behavior of the exoskeleton.
School of Meachanical & Aerospace Engineering (MAE)
Nanyang Technological University (NTU), Singapore
Upper Limb Soft Wearable Exoskeletons: State of the Art, Solutions and Challenges
In recent years, compliant actuation technology have been increasingly developed and employed in the new fields of robotic rehabilitation, haptics and wearable exoskeletons: devices where safety, limitation of peak forces and gentle interaction are extremely important. To date, several examples of robotic applications have been designed to address the demanding needs of these disciplines that require compliance in actuation and manipulation: gentle interaction with human in the loop. However, in some cases, control performance is not fully satisfied due to lack of accuracy of robotic system models, unmodeled nonlinearities, complex friction as well as actuator dynamics. In such cases, estimating the inverse dynamics model from collected data will provide an interesting alternative to achieve both compliant control and high tracking quality. In my talk I would like to introduce a new approach in wearable exosuits for upper limb assistance, based on composite materials and introducing a new algorithm which can learn an unknown system model from measured data using localization approach combined with Extreme Learning Machine.
Marcia K. O’Malley
Mechanical Engineering & Computer Science
Rice University, USA
Challenge and Engagement: Ensuring Effective Upper Limb Robotic Rehabilitation
The Mechatronics and Haptic Interfaces Lab at Rice University has been developing robotic devices, objective assessments, and control architectures for upper extremity rehabilitation robots employed after stroke and incomplete spinal cord injury. In this talk, a range of techniques for ensuring appropriate challenge and active engagement of the participant in therapeutic interventions with robotic devices will be discussed. Objective measures of motor impairment can provide frequent feedback to the participant regarding their performance during therapy. Control architectures can require initiation or sustained input from the user in order to generate desired movements. Further, controllers can be designed to adapt to the users changing capabilities, which may be dependent on position or direction of movement. Results from a variety of ongoing clinical evaluations will be discussed in relation to these topics.
University of Siena, Siena, Italy
and Istituto Italiano di Tecnologia, Genova, Italy
The Soft-SixthFinger: a Wearable EMG Controlled Robotic Extra-Finger for Grasp Compensation in Chronic Stroke Patients
We will presents the Soft-SixthFinger, a wearable robotic extra-finger designed to be used by chronic stroke patients to compensate for the missing hand function of their paretic limb. The extra-finger is an underactuated modular structure worn on the paretic forearm by means of an elastic band. The device and the paretic hand/arm act like the two parts of a gripper working together to hold an object. The patient can control the flexion/extension of the robotic finger through the eCap, an Electromyography (EMG) interface embedded in a cap. The user can control the device contracting the frontalis muscle by moving his or her eyebrows upwards. The Soft-SixthFinger has been designed as tool that can be used by chronic stroke patients to compensate for grasping in many Activities of Daily Living (ADL). It can be wrapped around the wrist and worn as a bracelet when not used. The light weight and the complete wireless connection with the EMG interface guarantee a high portability and wearability. We tested the device with qualitative experiments involving six chronic stroke patients. Results show that the proposed system significantly improves the performance of the considered tests and the autonomy in ADL.
Georgia Institute of Technology, USA
Robotic Induction of Neuromodulation in Human Motor System
This talk will introduce the speakers recent research effort that aims to apply a systems engineering approach to designing and assessing rehabilitation robots. The research approach is threefold: (1) design and control of high precision mechanisms, (2) modeling of human functions, and (3) understanding of interaction between human and robots. The goal of the research is to develop theories, methods, and tools to understand the mechanisms of neuromotor adaptation in human-robot physical interaction. A project supported by the U.S. National Science Foundation is introduced that aims to understand temporal dynamics of cortical facilitation with afferent stimulation for the assessment of stroke rehabilitation. A robotic device that combines magnetic brain stimulation and peripheral mechanical stimulation has been developed to reproduce paired associative simulation (PAS). Subjects receive this mechanical stimulation and magnetic brain stimulation with various time intervals between two in order to induce long-term potentiation (LTP). The research reveals that precise timing control of actuation is the key for successful robotic neuromodulation, not the speed of response.
Delft University of Technology, Netherlands
Multidimensional Physical Human-Robot Interaction
Neuro-rehabilitation robots or actuated artificial legs are particularly challenging examples of human-robot interfaces. The need for effective physical interaction of humans with these devices has been a major driving factor or new paradigms in mechanical design and control: Instead of high stiffness for precise position tracking, the applications require compliant human-robot interaction. An important prerequisite for such compliant regimes is that undesired interaction forces caused by robot dynamics should be minimal. This talk will present mechanical design principles that enable high-performance force rendering, such as underactuation, task-specific design, and the targeted use of serial and parallel compliance to shape dynamic behavior. Embodiments and experimental results for the concepts will be shown, like a highly transparent robot for overground gait training in rats, which enabled groundbreaking research on recovery after spinal cord injury, and a recent extension of the robotic principle to human scale. Special foci of the talk will be on compliant multidimensional actuation and on new actuation principles for wearable applications.
Department of Mechanical Systems Engineering
Tokyo University of Agriculture and Technology, Japan
What Role Motion Plays in Human-Robot Interaction? The Importance of Motion Dynamics
For most humans it is “natural” to interact with other humans and in particular to use non-verbal communication as a mean to convey intention, emotion and to give a purpose to an interaction. This presentation presents some our latest advances in human science and in particular to model and to understand human behavior and non-verbal communication through the dynamics of motions. Our research results are applied to human-machine interaction and human-robot interaction to create awareness: social awareness, emotional awareness, health awareness… and aim at creating a seamless intelligent environment where humans and machines can share the same space and collaborate. The presentation entwines concepts from the fields of AI, robotics, biomechanics, psychology and sociology.
Mechanical and Biomedical Engineering
Harvard University, USA
Soft Wearable Robots to Assist Manipulation and Mobility
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 and fabrication 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. 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 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 multimaterial fluid-powered actuators. These actuators are of particular interest to the robotics community because they are lightweight, inexpensive, easily fabricated with emerging digital fabrication techniques and capable of producing complex three-dimensional outputs with simple control inputs. This is accomplished via a multi-step molding process where some combination of fillers (e.g. cloth, paper, particles and fibers) is integrated into a soft elastomeric matrix to create anisotropy in the bulk material properties. Upon pressurization, embedded channels or chambers in the soft actuator then expand in directions with the lowest stiffness and give rise to linear, bending, and twisting motions.