Development of a wearable assistive soft robotic device for elbow rehabilitation

The loss of motor function at the elbow joint can result as a consequence of stroke. Stroke is a clinical illness resulting in long lasting neurological deficits often affecting somatosensory and motor cortices. More than half of those that recover from a stroke survive with disability in their upper arm and need rehabilitation therapy to help in regaining functions of daily living. In this paper, we demonstrated a prototype of a low-cost, ultra-light and wearable soft robotic assistive device that could aid administration of elbow motion therapies to stroke patients. In order to assist the rotation of the elbow joint, the soft modules which consist of soft wedge-like cellular units was inflated by air to produce torque at the elbow joint. Highly compliant rotation can be naturally realised by the elastic property of soft silicone and pneumatic control of air. Based on the direct visual-actuation control, a higher control loop utilised visual processing to apply positional control, the lower control loop was implemented by an electronic circuit to achieve the desired pressure of the soft modules by Pulse Width Modulation. To examine the functionality of the proposed soft modular system, we used an anatomical model of the upper limb and performed the experiments with healthy participants.

Soft balancing in the Americas: Latin American opposition to U.S. intervention, 1898–1936

In the aftermath of the 2003 U.S.-led invasion of Iraq, scholars of international relations debated how to best characterize the rising tide of global opposition. The concept of “soft balancing” emerged as an influential, though contested, explanation of a new phenomenon in a unipolar world: states seeking to constrain the ability of the United States to deploy military force by using multinational organizations, international law, and coalition building. Soft balancing can also be observed in regional unipolar systems. Multinational archival research reveals how Argentina, Mexico, and other Latin American countries responded to expanding U.S. power and military assertiveness in the early twentieth century through coordinated diplomatic maneuvering that provides a strong example of soft balancing. Examination of this earlier case makes an empirical contribution to the emerging soft-balancing literature and suggests that soft balancing need not lead to hard balancing or open conflict.