scholarly journals Design and Control of a New Biomimetic Transfemoral Knee Prosthesis Using an Echo-Control Scheme

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Mario G. Bernal-Torres ◽  
Hugo I. Medellín-Castillo ◽  
Juan C. Arellano-González
Keyword(s):  
Control Strategy ◽  
Knee Prosthesis ◽  
The Body ◽  
Metabolic Energy ◽  
Knee Prostheses ◽  
Human Knee ◽  
Knee Movement ◽  
Control Scheme ◽  
Sound Side ◽  
And Control

Passive knee prostheses require a significant amount of additional metabolic energy to carry out a gait cycle, therefore affecting the natural human walk performance. Current active knee prostheses are still limited because they do not reply with accuracy of the natural human knee movement, and the time response is relatively large. This paper presents the design and control of a new biomimetic-controlled transfemoral knee prosthesis based on a polycentric-type mechanism. The aim was to develop a knee prosthesis able to provide additional power and to mimic with accuracy of the natural human knee movement using a stable control strategy. The design of the knee mechanism was obtained from the body-guidance kinematics synthesis based on real human walking patterns obtained from computer vision and 3D reconstruction. A biomechanical evaluation of the synthesized prosthesis was then carried out. For the activation and control of the prosthesis, an echo-control strategy was proposed and developed. In this echo-control strategy, the sound side leg is sensed and synchronized with the activation of the knee prosthesis. An experimental prototype was built and evaluated in a test rig. The results revealed that the prosthetic knee is able to mimic the biomechanics of the human knee.

Development of an Active Biomimetic-Controlled Transfemoral Knee Prosthesis

2016 ◽  
Author(s):  
Mario G. Bernal-Torres ◽  
Hugo I. Medellín-Castillo ◽  
Juan C. Arellano-González
Keyword(s):  
Gait Cycle ◽  
Knee Prosthesis ◽  
Control Strategies ◽  
Human Motion ◽  
The Body ◽  
Metabolic Energy ◽  
Knee Prostheses ◽  
Additional Energy ◽  
Long Time ◽  
Four Bar Linkage

Commercial available knee prostheses are still limited because most of them comprise passive elements that store and deliver energy during the gait cycle, but without providing additional energy. This inability to provide additional energy affects the performance of passive prostheses, which in some cases demands up to 60% of additional metabolic energy to perform a gait cycle. Recent research works have focused on the design of active knee prostheses, including the development and implementation of control strategies such as electromyographic (EMG) signals. However, the results of such implementations reveal that these control strategies are still limited because of the relatively long time response and inaccurate movements. This paper presents the design of a new biomimetic-controlled knee prosthesis for transfemoral amputation. The aim is to contribute to the development of simple and effective active knee prostheses. The proposed prosthesis consists of a polycentric mechanism obtained from the body-guidance kinematics synthesis of a four bar linkage. This synthesis is based on the natural movements of the human knee, taking into account the shortening effect of the leg during the walking process to avoid trips. The prosthetic knee mimics the human motion of the healthy leg by means of an echo-control strategy. An experimental prototype has been implemented and tested on a workbench. The experimental results have demonstrated the usability of the proposed biomimetic active knee prosthesis.

NEURAL MODELING AND CONTROL OF DYNAMIC SYSTEMS WITH HYSTERESIS

2007 ◽  
Vol 31 (1) ◽  
pp. 127-141
Author(s):  
Yonghong Tan ◽  
Xinlong Zhao
Keyword(s):  
Dynamic Systems ◽  
Control Strategy ◽  
Neural Modeling ◽  
Modeling And Control ◽  
Control Scheme ◽  
The Neural Networks ◽  
Adaptive Control Strategy ◽  
Set Up ◽  
Modeling Strategy ◽  
And Control

A hysteretic operator is proposed to set up an expanded input space so as to transform the multi-valued mapping of hysteresis to a one-to-one mapping so that the neural networks can be applied to model of the behavior of hysteresis. Based on the proposed neural modeling strategy for hysteresis, a pseudo control scheme is developed to handle the control of nonlinear dynamic systems with hysteresis. A neural estimator is constructed to predict the system residual so that it avoids constructing the inverse model of hysteresis. Thus, the control strategy can be used for the case where the output of hysteresis is unmeasurable directly. Then, the corresponding adaptive control strategy is presented. The application of the novel modeling approach to hysteresis in a piezoelectric actuator is illustrated. Then a numerical example of using the proposed control strategy for a nonlinear system with hysteresis is presented.

scholarly journals Development and Examination of a Knee Prosthesis Geometry

2019 ◽  
Vol 11 (1) ◽  
pp. 27-30
Author(s):  
Gábor Péter Balassa
Keyword(s):  
Knee Joint ◽  
Research Team ◽  
Knee Prosthesis ◽  
Experimental Measurements ◽  
Joint Movement ◽  
Knee Prostheses ◽  
Healthy Human ◽  
Human Knee ◽  
Human Knee Joint ◽  
Number Of Patients

Abstract The necessity for the knee prosthesis is confirmed by the large increase in the number of patients suffering from arthrosis, which is a present-day disease. Despite this need, there doesn’t exist an optimal knee prosthesis. Nowadays the development of the knee prostheses is progressing. It is very difficult to define the required geometry with traditional methods, because the movement conditions to be created by the prostheses should be similar to the movements of the human knee. During previous research the biomechanical research team of the Szent István University occupied with experimental measurements of the healthy human knee joint movement. In this paper I would like to introduce a method of prosthesis geometry development. As a result, a knee prosthesis geometry has been created which is approaching the movement form of the real human knee joint.

Modeling and control through leadership of a refined flocking system

2014 ◽  
Vol 25 (02) ◽  
pp. 255-282 ◽  
Author(s):  
Alfio Borzì ◽  
Suttida Wongkaew
Keyword(s):  
Predictive Control ◽  
Control Strategy ◽  
Social Systems ◽  
Open Loop ◽  
Modeling And Control ◽  
Control Scheme ◽  
Nonlinear Conjugate Gradient ◽  
Optimality Systems ◽  
And Control ◽  
Conjugate Gradient Solver

A new refined flocking model that includes self-propelling, friction, attraction and repulsion, and alignment features is presented. This model takes into account various behavioral phenomena observed in biological and social systems. In addition, the presence of a leader is included in the system in order to develop a control strategy for the flocking model to accomplish desired objectives. Specifically, a model predictive control scheme is proposed that requires the solution of a sequence of open-loop optimality systems. An accurate Runge–Kutta scheme to discretize the optimality systems and a nonlinear conjugate gradient solver are implemented and discussed. Numerical experiments are performed that investigate the properties of the refined flocking model and demonstrate the ability of the control strategy to drive the flocking system to attain a desired target configuration and to follow a given trajectory.

Toward the Development of Knee Prostheses: Review of Current Active Devices

2019 ◽  
Vol 71 (3) ◽  
Author(s):  
Rafael R. Torrealba ◽  
Edgar D. Fonseca-Rojas
Keyword(s):  
Clinical Assessment ◽  
Control Strategy ◽  
Selection Criteria ◽  
Performance Metrics ◽  
Mechanical Design ◽  
Knee Prostheses ◽  
Active Devices ◽  
Scientific Papers ◽  
Transfemoral Amputees ◽  
And Control

This paper presents a thorough review of the initiatives carried out in the last 10 years toward the development of active knee prostheses (AKP) for transfemoral amputees. Three selection criteria were employed to filter the works to be considered in the review: (1) a prototype of the prosthesis is available; (2) the mechanical design, instrumentation, and control strategy of such a prototype have been presented in a scientific disclosure media; and (3) the prototype has been subjected to clinical assessment at least in a preliminary way. After applying such criteria, 16 projects were selected and further reviewed through a total of 31 scientific papers, considering the following six aspects: (1) actuators, (2) instrumentation, (3) control, (4) testing trials, (5) performance metrics, and (6) limitations. Then, in addition, the chronological appearance of the aforesaid papers is also shown and quantified regarding each of the previously mentioned issues, to initiate discussion on the related topics. Thus, the present review results in a specialized summary of all these developments in a structured format, offering additional understanding of the recent advances achieved in this field.

scholarly journals Decentralized Mesh-Based Model Predictive Control for Swarms of UAVs

Sensors ◽  
2020 ◽  
Vol 20 (15) ◽  
pp. 4324
Author(s):  
Salvatore Rosario Bassolillo ◽  
Egidio D’Amato ◽  
Immacolata Notaro ◽  
Luciano Blasi ◽  
Massimiliano Mattei
Keyword(s):  
Model Predictive Control ◽  
Unmanned Aerial Vehicles ◽  
Predictive Control ◽  
Control Strategy ◽  
Target Area ◽  
Guidance And Control ◽  
Aerial Vehicles ◽  
Control Scheme ◽  
And Control ◽  
Numerical Simulator

This paper deals with the design of a decentralized guidance and control strategy for a swarm of unmanned aerial vehicles (UAVs), with the objective of maintaining a given connection topology with assigned mutual distances while flying to a target area. In the absence of obstacles, the assigned topology, based on an extended Delaunay triangulation concept, implements regular and connected formation shapes. In the presence of obstacles, this technique is combined with a model predictive control (MPC) that allows forming independent sub-swarms optimizing the formation spreading to avoid obstacles and collisions between neighboring vehicles. A custom numerical simulator was developed in a Matlab/Simulink environment to prove the effectiveness of the proposed guidance and control scheme in several 2D operational scenarios with obstacles of different sizes and increasing number of aircraft.

scholarly journals Leader-Following Control System Design Based on Back-stepping Control Strategy

2020 ◽  
Author(s):  
Dong-Hun Lee ◽  
Duc-Quan Tran ◽  
Young-Bok Kim
Keyword(s):  
Control System ◽  
Motion Control ◽  
Control Strategy ◽  
Pid Control ◽  
Control Method ◽  
Nonlinear Parameters ◽  
Control Scheme ◽  
Leader Following ◽  
Back Stepping Control ◽  
And Control

In this study, a motion control problem for the vessels towed by tugboats or towing ships on the sea is considered. The towed vessels including barge ships are need to have assistance of tugboats. Combining two vessels, some work purposes in the sea or harbor area can be completed. In this study, the authors give newly developed mathematical model and control system strategy. Especially, the system model fully presenting the physical characteristics of two vessels are derived. For controlling the system effectively, it is considered that the towed vessel has no power propulsion system but the rudder is activated to improve the maneuverability. Considering the strong nonlinearities included in the vessel dynamics, the modelled system is presented by nonlinear system without linearization of nonlinear parameters. Thus, the control system for the towed vessel is designed based on the nonlinear control scheme. Exactly, the back-stepping control method is applied to its motion control. Also, the PID control method is applied for comparing with the proposed control strategy.

Vorticity dynamics and control of the turning locomotion of 3D bionic fish

2018 ◽  
Vol 232 (14) ◽  
pp. 2524-2535 ◽  
Author(s):  
Zhiqiang Xin ◽  
Chuijie Wu
Keyword(s):  
Control Strategy ◽  
The Body ◽  
Immersed Boundary ◽  
Directional Control ◽  
Depth Analysis ◽  
Dynamics And Control ◽  
Turning Motion ◽  
Volume Method ◽  
And Control ◽  
3D Bionic Fish

Numerical simulations of the turning manoeuvre of a 3D bionic fish in a viscous flow are conducted in the present study using a 3D computational fluid dynamics package, which includes the adaptive multi-grid finite volume method, the immersed boundary method, the volume of fluid method, and the control strategy of fish swimming. The 3D bionic fish can turn quickly primarily using the directional control strategy of the swing of the head, in which the impacts of the swing of the fish body and the caudal fin on the directional control are also taken into account. This result demonstrates that the directional control strategy of the swing of the head is effective. An in-depth analysis of the fluid mechanism of the swimming manoeuvre of the 3D bionic fish reveals that the rotation moment in favour of turning motion is obtained by the pressure around the body of the fish, which is induced by the wake vortex, and the swing of the fish can manipulate the location and the strength of vortices shed from the fish body.

Practical Strategies for Controlling Railway Wheelsets Independently Rotating Wheels

2003 ◽  
Vol 125 (3) ◽  
pp. 354-360 ◽  
Author(s):  
T. X. Mei ◽  
R. M. Goodall
Keyword(s):  
Control Strategy ◽  
Ride Comfort ◽  
Control Structure ◽  
The Body ◽  
Vehicle Speed ◽  
Control Scheme ◽  
Curving Performance ◽  
Rail Deflection ◽  
Optimal Control Scheme ◽  
Active Control Strategy

This paper presents the development of an active control strategy for railway vehicles with independently rotating wheels. The proposed control scheme is intuitively formulated with a simple control structure and adaptive to vehicle speed. It does not require basic guidance measurements (e.g., wheel-rail deflection and angle of attack) that are expensive and impractical to implement. Speed sensors are used to measure the relative rotational speed of the two wheels on a same axle and sensors are also used to measure the relative yaw velocity of the wheelset and the body it is connected. Both curving performance and passenger ride comfort of the actively controlled vehicle are compared with that of a typical passive vehicle and an optimal control scheme.

scholarly journals A New Seamless Transfer Control Strategy of the Microgrid

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Zhaoyun Zhang ◽  
Wei Chen ◽  
Zhe Zhang
Keyword(s):  
Control Strategy ◽  
Mode Conversion ◽  
Control Device ◽  
Control Logic ◽  
Mode Control ◽  
Control Scheme ◽  
Simulation Results ◽  
Seamless Transfer ◽  
And Control

A microgrid may operate under two typical modes; the seamless transfer control of the microgrid is very important. The mode conversion controller is installed in microgrid and the control logic of master power is optimized for microgrid mode conversion. In the proposed scheme, master power is very important. The master-power is under the PQ control when microgrid is under grid-connected. And it is under V/F control when the microgrid is under islanding. The microgrid mode controller is used to solve the planned conversion. Three types of conversion are simulated in this paper. The simulation results show the correctness and validity of the mode control scheme. Finally, the implementation and application of the operation and control device are described.

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