Active ankle foot orthosis
First Claim
1. An autonomous motorized permanent assistance device comprising:
- a mechanical ankle joint;
an actuator adapted to exert a torque about the ankle joint, the actuator comprising;
a motor; and
a spring operatively coupled with the motor;
at least one sensor adapted to determine at least one of a position, a velocity, and a force; and
a controller adapted to control the motor to change spring compression during a gait cycle to modulate at least one of joint torque, stiffness, damping, position or speed based at least in part on the at least one sensor.
1 Assignment
0 Petitions
Accused Products
Abstract
An Active Ankle Foot Orthosis (AAFO) is provided where the impedance of an orthotic joint is modulated throughout the walking cycle to treat ankle foot gait pathology, such as drop foot gait. During controlled plantar flexion, a biomimetic torsional spring control is applied where orthotic joint stiffness is actively adjusted to minimize forefoot collisions with the ground. Throughout late stance, joint impedance is minimized so as not to impede powered plantar flexion movements, and during the swing phase, a torsional spring-damper (PD) control lifts the foot to provide toe clearance. To assess the clinical effects of variable-impedance control, kinetic and kinematic gait data were collected on two drop foot participants wearing the AAFO. It has been found that actively adjusting joint impedance reduces the occurrence of slap foot, allows greater powered plantar flexion, and provides for less kinematic difference during swing when compared to normals.
-
Citations
27 Claims
-
1. An autonomous motorized permanent assistance device comprising:
-
a mechanical ankle joint; an actuator adapted to exert a torque about the ankle joint, the actuator comprising; a motor; and a spring operatively coupled with the motor; at least one sensor adapted to determine at least one of a position, a velocity, and a force; and a controller adapted to control the motor to change spring compression during a gait cycle to modulate at least one of joint torque, stiffness, damping, position or speed based at least in part on the at least one sensor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
Specification