How advanced are current wearable exoskeletons and what interactions are possible?
Wearable exoskeletons are coming to stay. Technological advancements in embedded computation and wearable mechatronics are enabling the production of new wearable exoskeletons that were not feasible a decade ago.
The human robot interface and control algorithms are in the process of consolidation. Current interfaces allow for relatively accurate estimation of human motion intention enabling more and more the availability of these robots for assistive purposes in daily life and also as therapeutic tools for personalized treatment of neurological disorders.
Please can you give a brief history of wearable exoskeletons?
Modern lower limb robotic exoskeletons appeared in 1960s. Many studies have been carried out in the field since then.
Remarkably, in the last five years, an exponential increase in research on development of exoskeletons for spinal cord injured patients and stroke survivors has been seen, with crucial advances to improve the wearability, portability and the performance of the robotic exoskeletons.
More compact and light actuators have been developed together with comfortable and dependable human robot interfaces that can be powered by more efficient wearable power supplies.
What impact have advances in robotic technology had on exoskeletons?
Control strategies and actuators technologies have been applied and optimized for use in wearable exoskeletons for support and assistance of humans.
In particular, more compact actuation solutions have been produced that can provide torque in the required ranges.
Control approaches to implement mechanical compliance for safety and human-like performance have also important impact on the current status of exoskeleton technology.
Please can you outline your work on the potential to use wearable exoskeletons as a diagnostic tool?
Wearable exoskeletons can be used as unique tools to quantify the motor function of neurologically injured individuals.
Wearable sensors in these robots and new interfaces with central nervous system allow for detailed assessment and monitoring of biomechanics and neuromotor deficits in subjects with movement impairments.
What are the main challenges that need to be overcome in order to advance wearable exoskeletons?
The main challenges to advance wearable exoskeletons are the following:
- More compact and lightweight actuators;
- Improve the burden of mechanical structure on the movement patterns;
- More natural and robust interfaces to detect the motion intent;
- Adaptability and learning approaches should be investigated to balance safety with more versatile function to handle multiple situations.
What specific patient needs have to be taken into account when designing wearable exoskeletons?
General needs are reliability, usability, comfort, safety and repeatability. In a rehabilitative approach the most important aspects of the targeted function should be considered.
Other important features are simplicity (easy to use, understand, prepare), low weight, aesthetics, and avoidance of side effects.
What do you think the future holds for wearable exoskeletons and what interactions do you think will be possible going forwards?
Machine learning techniques are likely to bring new control paradigms for assistive wearable exoskeletons for daily use.
Modularity in new wearable exoskeleton robots will be useful to link therapeutic with compensatory/assistive approaches.
Interaction with manufacturing industry for custom design and fast prototyping will be critical to improve current designs and widen the scale of production.
Where can readers find more information?
About Dr Juan C. Moreno
Head of Human Locomotion Laboratory (Neural Rehabilitation Group) in Cajal Institute at CSIC in Madrid, Spain. His main research interests include rehabilitation robotics and neuroprosthetics, and specially the optimization of these technologies for the neurological rehabilitation after stroke and spinal cord injury, analysis and synthesis of neural control of human walking and biomechanical simulations.
He was the recipient of TR35 Spain 2012 Award by Massachusetts Institute of Technology’s journal, Technology Review for his work on technology for a more efficient rehabilitation of people with limited mobility. In 2011 he received Princess Infanta Cristina Award by the Spanish Institute for Older People and Social Services in the research, development and innovation category for his work on intelligent gait exoskeletons and orthoses. He is the Principal Investigator of the European Project BIOMOT, developing symbiotic wearable exoskeleton for gait training after spinal cord injuries.