Exoskelets

Exoskelets are external skeletons or wearable systems designed to provide structural support or augment movement. The term can describe biological exoskeletons in living organisms and technological exoskelets, which are powered or passive devices worn on the body. In biology, exoskeletons are rigid external coverings that support muscle action, protect soft tissues, and limit water loss in terrestrial species. They are found in most arthropods and some mollusks; growth requires periodic shedding (molting). In technology, exoskelets refer to devices attached to the body to assist, enhance, or restore movement. These devices range from passive supports that redistribute loads to powered suits that use actuators and control systems to amplify strength or endurance.

Mechanical exoskelets consist of a frame that anchors to the legs, hips, back, or arms, actuators (electric motors, hydraulics, or pneumatics), sensors (motion, force, or impedance), a control system, and a power source such as a rechargeable battery. They are categorized as passive, semi-active, or active (powered). Applications include industrial lifting and material handling, medical rehabilitation and mobility assistance for people with lower-limb weakness, and military or emergency response tasks. Benefits include reduced muscle fatigue, lower risk of injury, and expanded functional capabilities; challenges include weight, cost, energy duration, fit and comfort, safety, and user training.

The development of exoskelets accelerated in the late 20th and early 21st centuries, with early research laying the groundwork and modern commercial and clinical devices appearing since the 2010s. Ongoing work focuses on improving autonomy, intuitiveness, battery capacity, and integration with human movement.