adminEXOSKELETON
An exoskeleton acts as a force multiplier or amplifier, where the output force is far greater than the input force. Specifically, an exoskeleton is a wearable machine that provides support, protection and mobility to the human body. Exoskeletons enhance or restore human mobility, strength and endurance.
There are several types of exoskeletons and they are; passive, active, soft and hybrid exoskeleton.
Passive exoskeleton provides support and stability to the body without any active movement or actuation. Thus passive exoskeleton relies on the user’s movement without any actuation devices. They are simple and low cost devices with limited support structures. They are often used for injury prevention and rehabilitation. Examples include; spring loaded knee braces, bionic kangaroo exosuit, atlas exoskeleton, spring loaded exoskeleton, soft shell exoskeleton etc.
Active exoskeletons have actuators, sensors and control systems incorporated that enables them to move and provide assistance to the wearer. Active exoskeletons are powered by an active actuation device such as electric or hydraulic motors. They have a fully supported adjustable structure but are complex and dependent on power to operate satisfactorily. They are often used for mobility enhancement and strength augmentation. Examples include; Rewalk exosuit, Ekso bionics exoskeleton, Hocoma Lokomat, Lockheed Martin FEXO etc.
Soft exoskeletons are flexible and wearable devices designed for individuals with mobility impairments, providing soft and flexible support for the human body. They are light weight structures and are comfortable to use, though with limited force output. They are useful as medical and industrial support structures. Examples include; soft exosuit, Sew-R-Lite exoskeleton, soft robotics exoskeleton, pneumatic muscle exoskeleton etc.
Hybrid exoskeletons combine passive and active components to provide both support and powered movements. They balance the efficiency and support structures of both types of exoskeletons. However they are complex in their design, challenging to operate and maintain. They are especially used for industrial, military and rehabilitation assistance. Examples include; BLEEX exoskeleton, hybrid assistance exoskeleton (HAE), intelligent assistive exoskeleton (IAE), Restore exoskeleton etc.
The advantages of exoskeletons are; exoskeletons can enable individuals with mobility impairments to stand and walk. Exoskeletons can provide strength augmentation, allowing individuals to perform tasks that would otherwise be difficult or impossible. Exoskeletons can provide support and stability, reducing the risk of injury and strain. Exoskeletons can reduce fatigue and enhance endurance, allowing for individuals to perform tasks for longer periods.
The disadvantages of exoskeletons are; exoskeletons can be expensive making them inaccessible to the poor. Exoskeletons can be heavy and bulky making them difficult to wear and maneuver with ease. Exoskeletons often require external power sources and control systems limiting their autonomy and independence. Exoskeletons often require extensive trainings and support, which can be time consuming and costly.
Exoskeletons find applications in the following; medical rehabilitation where exoskeletons like Rewalk and cyberdyne HAL help patients with mobility impairments such as spinal cord injuries or strokes regain movement and independence. Exoskeletons are used in the military such as Lockheed martin’s ONYX and SARCOS guardian XO exoskeletons to enhance soldier performance by allowing them to carry heavy loads with reduced fatigue and injury risk. Exoskeletons are used for industrial work aid where wearable suits such as EKKO Vest and suit X support workers in construction, manufacturing and logistics, reducing physical strain and injury risk. Exoskeletons are used for elderly mobility where devices such as seismic’s soft robotic garments assist elderly individuals with movement and balance.
The future of exoskeletons is based on the advances and development of the following technologies; advances in materials and manufacturing, to reduce the weight and cost of exoskeletons. Increase autonomy with advanced control systems and powered sources. Future exoskeletons are expected to be designed to integrate more closely with the human body. Exoskeletons are expected in the future to be more widely accepted and adopted in various industries as standards for work and applications in healthcare, military and so on.
SOURCES:
- Wearable exoskeleton systems : Design, control and applications edited by Shaoping Bai, Gurvinder Singh Virk and Thomas Sugar.
- Exoskeleton robots for rehabilitation and health care devices by Manuel Cardona, Vijender Kumar Solanki and Cecilia E. Garcia Cena.
- Wearable robots, bio mechatronic exoskeletons by Jose L. Pons.
- Introduction to Bio mechatronics by Graham Brooker.
- Bio mechatronics in medicine and healthcare by Raymond Tong.
