A Pneumatic Artificial Muscle Articulated Knee Prosthesis

2010 ◽  
Author(s):  
Garrett Waycaster ◽  
Sai-Kit Wu ◽  
Xiangrong Shen
Keyword(s):  
Mechanical Design ◽  
Knee Prosthesis ◽  
Artificial Muscle ◽  
Stair Climbing ◽  
Pneumatic Artificial Muscle ◽  
Motion Controller ◽  
Control Approach ◽  
Energy Consuming ◽  
Human Motor ◽  
And Control

This paper describes the mechanical design and control approach for an above-knee (AK) prosthesis actuated by pneumatic artificial muscle. Pneumatic artificial muscle (PAM) affords great potential in prosthetics, since this type of actuator features a high power density, and similar characteristics to human muscles. However, there is no application of PAM in AK prosthetics in existing literature to the best knowledge of the authors. In this paper, a design of the prosthesis is presented, which provides sufficient actuation torque for the knee joint in energy consuming locomotive functions such as fast walking and stair climbing. The corresponding control approach is developed to mimic the human motor control in locomotive functions, which includes a lower-level equilibrium-point hypothesis-inspired motion controller, and a higher-level joint-behavior-based motion planner.

A Pneumatic Artificial Muscle Actuated Above-Knee Prosthesis

2010 ◽  
Author(s):  
Garrett Waycaster ◽  
Sai-Kit Wu ◽  
Xiangrong Shen
Keyword(s):  
Sliding Mode ◽  
Mechanical Design ◽  
Knee Prosthesis ◽  
Artificial Muscle ◽  
Torque Control ◽  
Stair Climbing ◽  
Pneumatic Artificial Muscle ◽  
Control Approach ◽  
Energy Consuming ◽  
And Control

This paper describes the mechanical design and control approach for an above-knee (AK) prosthesis actuated by pneumatic artificial muscle. Pneumatic artificial muscle (PAM) affords great potential in prosthetics, since this type of actuator features a high power density, and similar characteristics to human muscles. However, there is no application of PAM in AK prosthetics in existing literature to the best knowledge of the authors. In this paper, a design of the prosthesis is presented, which provides sufficient actuation torque for the knee joint in energy consuming locomotive functions such as fast walking and stair climbing. The corresponding control approach is also presented, which combines an impedance-based locomotive controller with a lower-level sliding-mode torque control approach. Experiments on the proposed AK prosthesis have also been conducted to demonstrate the ability to mimic normal gait characteristics.

Design and Control of a Pneumatic Artificial Muscle Actuated Above-Knee Prosthesis

2011 ◽  
Vol 5 (3) ◽  
Author(s):  
Garrett Waycaster ◽  
Sai-Kit Wu ◽  
Xiangrong Shen
Keyword(s):  
Control Algorithm ◽  
Knee Prosthesis ◽  
Radial Profile ◽  
Artificial Muscle ◽  
Torque Control ◽  
Effective Control ◽  
Pneumatic Artificial Muscle ◽  
Knee Prostheses ◽  
Control Approach ◽  
Highly Nonlinear

This paper presents the authors’ investigation results of applying the pneumatic artificial muscle actuation to above-knee prostheses. As a well-known muscle actuator, the pneumatic artificial muscle actuator features a number of unique advantages, including high power density, and similar elastic characteristics to biological muscles. Despite multiple applications in related areas, the application of pneumatic artificial muscle in above-knee prostheses has not been explored. Inspired by this fact, the research presented in this paper aims to develop a pneumatic artificial muscle-actuated above-knee prosthesis, with three specific objectives: (1) demonstrate the pneumatic artificial muscle actuation’s capability in generating sufficient torque output to meet the locomotive requirements; (2) develop an effective control approach to enable the restoration of locomotive functions; (3) conduct preliminary testing of the prosthesis prototype on a healthy subject through a specially designed able-body adaptor. In the prosthesis design, an agonist–antagonist layout is utilized to obtain a bidirectional motion. To minimize the radial profile, an open-frame structure is used, with the purpose of allowing the expansion of the muscle actuators into the center space without interference. Also, the muscle actuator parameters are calculated to provide sufficient torque capacity (up to 140 N m) to meet the requirements of level walking. According to this design, the fabricated prototype weighs approximately 3 kg, with a range of motion of approximately 100°. For the control of the prosthesis, a model-based torque control algorithm is developed based on the sliding mode control approach, which provides robust torque control for this highly nonlinear system. Combining this torque control algorithm with an impedance-based torque command generator (higher-level control algorithm), the fabricated prosthesis prototype has demonstrated a capability of providing a natural gait during treadmill walking experiments.

Design and Control of a Compact and Flexible Pneumatic Artificial Muscle Actuation System: Part Two—Robust Control

2011 ◽  
Author(s):  
Sai-Kit Wu ◽  
Garrett Waycaster ◽  
Tad Driver ◽  
Xiangrong Shen
Keyword(s):  
Robust Control ◽  
Nonlinear Model ◽  
Sliding Mode ◽  
Artificial Muscle ◽  
Control Approach ◽  
Actuation System ◽  
Highly Nonlinear ◽  
Pressure Dynamics ◽  
System Part ◽  
And Control

A robust control approach is presented in this part of the paper, which provides an effective servo control for the novel PAM actuation system presented in Part I. Control of PAM actuation systems is generally considered as a challenging topic, due primarily to the highly nonlinear nature of such system. With the introduction of new design features (variable-radius pulley and spring-return mechanism), the new PAM actuation system involves additional nonlinearities (e.g. the nonlinear relationship between the joint angle and the actuator length), which further increasing the control difficulty. To address this issue, a nonlinear model based approach is developed. The foundation of this approach is a dynamic model of the new actuation system, which covers the major nonlinear processes in the system, including the load dynamics, force generation from internal pressure, pressure dynamics, and mass flow regulation with servo valve. Based on this nonlinear model, a sliding mode control approach is developed, which provides a robust control of the joint motion in the presence of model uncertainties and disturbances. This control was implemented on an experimental setup, and the effectiveness of the controller demonstrated by sinusoidal tracking at different frequencies.

Wheel-Based Stair Climbing Robot with Hopping Mechanism – Demonstration of Continuous Stair Climbing Using Vibration –

2008 ◽  
Vol 20 (2) ◽  
pp. 221-227 ◽  
Author(s):  
Yuji Asai ◽  
◽  
Yasuhiro Chiba ◽  
Keisuke Sakaguchi ◽  
Naoki Bushida ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Mechanical Design ◽  
Stair Climbing ◽  
Design Parameters ◽  
Mass Ratio ◽  
Climbing Robot ◽  
Soft Landing ◽  
Hopping Mechanism ◽  
And Control ◽  
Two Bodies

We propose a simple hopping mechanism using vibration of a two-degrees-of-freedom (2-DOF) system for a fast stair-climbing robot. The robot, consisting of two bodies connected by springs and a wire, hops by releasing energy stored in springs and travels quickly using wheels mounted on its lower body. The trajectories of bodies during hopping change based on mechanical design parameters such as reduced mass of the two bodies, the mass ratio between the upper and lower bodies, and spring constant, and control parameters such as initial contraction of the spring and wire tension. This property allows the robot to quickly and economically climb stairs and land softly without complex control. In this paper, we propose a mathematical model of the robot and investigate required tread length for continuous hopping to climb a flight of stairs. Furthermore, we demonstrate fast stair-climbing and soft landing for a flight of stairs in experiments.

204 Modeling and Control of Pneumatic Artificial Muscle Actuator

2008 ◽  
Vol 2008.83 (0) ◽  
pp. _2-4_
Author(s):  
Nobutaka TSUJIUCHI ◽  
Takayuki KOIZUMI ◽  
Hiroto KAN ◽  
Shinya NISHINO ◽  
Tatsuwo KUDAWARA ◽  
...  
Keyword(s):  
Artificial Muscle ◽  
Pneumatic Artificial Muscle ◽  
Modeling And Control ◽  
And Control

Design and Control of a Compact and Flexible Pneumatic Artificial Muscle Actuation System: Part One—Design Process

2011 ◽  
Author(s):  
Garrett Waycaster ◽  
Sai-Kit Wu ◽  
Tad Driver ◽  
Xiangrong Shen
Keyword(s):  
Controller Design ◽  
Artificial Muscle ◽  
The Other ◽  
Robotic Systems ◽  
Pneumatic Artificial Muscle ◽  
Actuation System ◽  
Torque Curve ◽  
System Part ◽  
New Feature ◽  
And Control

This paper describes the design and control of a compact and flexible pneumatic artificial muscle (PAM) actuation system for bio-robotic systems. The entire paper is divided into two parts, with the first part covering the mechanism design and the second part covering the corresponding controller design. This novel system presented in this part incorporates two new features, including a variable-radius pulley based PAM actuation mechanism, and a spring-return mechanism to replace the PAM in the “weak” direction. With the pulley radius as a function of the joint angle, this new feature enables the designer to freely modulate the shape of the torque curve, and thus achieves a significantly higher flexibility than the traditional configuration. The other new feature, the spring-return mechanism, is inspired by the fact that a large number of bio-robotic systems require a significantly larger torque in one direction than the other.

Walking-Stair Climbing Control for Powered Knee Prostheses

2016 ◽  
Author(s):  
Molei Wu ◽  
Xiangrong Shen
Keyword(s):  
Impedance Control ◽  
Knee Prosthesis ◽  
Stair Climbing ◽  
Knee Joints ◽  
Knee Prostheses ◽  
Control Approach ◽  
Prosthetic Joints ◽  
Real Time Measurement ◽  
Human Subject Testing ◽  
Finite State

Recent progresses in powered lower-limb prostheses have the potential of enabling amputee users to conduct energetically demanding locomotive tasks, which are usually beyond the capability of traditional unpowered prostheses. Realizing such potential, however, requires responsive and reliable control of the power provided by prosthetic joints. In this paper, an integrated walking-stair climbing control approach is presented for transfemoral prostheses with powered knee joints. Leveraging the similarities between walking and stair climbing, this new approach adopts the general finite-state impedance control framework. Furthermore, important modifications are introduced to model the biomechanical characteristics that are beyond the capability of standard impedance control. The transition between the walking and stair-climbing modes is triggered through the real-time measurement of the spatial orientation of the user’s thigh, which provides a reliable indicator of the user’s intention of making such transition. This new control approach has been implemented on a powered knee prosthesis, and its effectiveness was demonstrated in human subject testing.

scholarly journals 2A2-J03 Modelling and Control of Two link mechanism Driven by Pneumatic Artificial Muscle Actuator(Mechanism and Control for Actuator)

2011 ◽  
Vol 2011 (0) ◽  
pp. _2A2-J03_1-_2A2-J03_4
Author(s):  
Nobutaka TSUJIUCHI ◽  
Takayuki KOIZUMI ◽  
Tomoyuki MIZUNO ◽  
Masashi KIMURA ◽  
Hiroyuki KOJIMA ◽  
...  
Keyword(s):  
Artificial Muscle ◽  
Pneumatic Artificial Muscle ◽  
Link Mechanism ◽  
And Control

Integrated Design and Control of a Biped Robot

2005 ◽  
Author(s):  
James P. Schmiedeler ◽  
Eric R. Westervelt ◽  
Adam R. Dunki-Jacobs
Keyword(s):  
Performance Enhancement ◽  
Mechanical Design ◽  
Integrated Design ◽  
Biped Robot ◽  
Systematic Design ◽  
Biped Robots ◽  
Control Approach ◽  
Design Changes ◽  
And Performance ◽  
And Control

This paper introduces a methodology for the integration of mechanical and control system design of planar biped robots. The control approach is a procedure for the systematic design, analysis, and performance enhancement of controllers that induce provably stable dynamic walking in planar bipeds. Iterative application of this procedure with variations in the mechanical parameters of the biped model enables a designer to drive design changes based upon analytical metrics of stability and efficiency. The outcomes are a dynamically-informed mechanical design and controllers that maximally exploit the unforced dynamics of that design. This methodology has been applied to the design and construction of the prototype biped BIRT (BIped Robot with Three legs). BIRT is a planar biped whose two outside legs are slaved by means of control to act together. The paper provides a detailed description of BIRT’s mechanical system.

Sign in / Sign up

Export Citation Format

Share Document