A Pneumatic Manipulator used in Direct Contact with an Operator (original) (raw)

Pneumatic assistant of one degree of freedom for lifting

— Exoskeletons are wearable robots i.e. robots coupled to the body of a user and commanded by him/her. The fields of application involve among others, the military as well as the medical industries. This paper presents the design of part of an exoskeleton aimed to enhance the performance of people that have had spinal injury or that suffer from some problem or pain in the lumbar area. An experimental platform was built that allows the wearer to perform his/her tasks without making a big effort that could cause pain or injuries in the lumbar zone. The experimental platform employs Pneumatic Artificial Muscles (PAM) as actuators because they are suitable for applications were force is required. However being these actuators highly nonlinear devices, the control as well as the electronics involved in the design of the experimental set up are not a simple tasks. The experimental set up presented here is a one degree of freedom device attached to the trunk of a user. To start with a PD controller was employed. This set up is part of a bigger project that considers a complete exoskeleton that involves the four limbs and the middle part of a human body. However this device can be used to assist, as mentioned before, people with problems in the lumbar area.

Design, Construction and Control of a Manipulator Driven by Pneumatic Artificial Muscles

Sensors

This paper describes the design, construction and experimental testing of a single-joint manipulator arm actuated by pneumatic artificial muscles (PAMs) for the tasks of transporting and sorting work pieces. An antagonistic muscle pair is used in a rotational sense to produce a required torque on a pulley. The concept, operating principle and elementary properties of pneumatic muscle actuators are explained. Different conceptions of the system realizations are analyzed using the morphological-matrix conceptual design framework and top-rated solution was practically realized. A simplified, control-oriented mathematical model of the manipulator arm driven by PAMs and controlled with a proportional control valve is derived. The model is then used for a controller design process. Fluidic muscles have great potential for industrial applications and assembly automation to actuate new types of robots and manipulators. Their characteristics, such as compactness, high strength, high power-to...

Pleated pneumatic artificial muscles: actuators for automation and robotics

2001 IEEE/ASME International Conference on Advanced Intelligent Mechatronics. Proceedings (Cat. No.01TH8556), 2001

This contribution reports on a type of pneumatic artificial muscles (PAMs) that was recently developed at the Vrije Universiteit Brussel, department of Mechanical Engineering. Its distinguishing feature is its pleated design. Due to this, it has a very high contraction force and an equally high travel. The weight of these pleated PAMs is very low: a muscle of only 60 gr can pull up to 3500 N and contract by an amount of 42%. Furthermore, dry friction and associated hysteresis, typical of many other designs, is avoided by the folding-unfolding action. This significantly simplifies position control using these actuators. Although the force-displacement characteristics of our actuators are non-linear, they can be effectively controlled using basic linear PI techniques. Another advantage of these actuators is their inherent and controllable compliance, making them ideally suited for walking/running machines or whenever delicate tasks, e.g. handling fragile objects, have to be performed. In view of all characteristics pleated PAMs are very well suited for automation and robotic applications.

Studies on the Applicability of the Pneumatic Muscle in Industry

journals.indexcopernicus.com

The evolution underwent by the technology during the last decade facilitated utilization of pneumatic muscle in many applications, particularly in the field of industrial robots. The pneumatic muscles are lightweight actuators, able to generate high torques at low and moderate speeds, ...

Pneumatic muscle actuators within robotic and mechatronic systems

2015

Pneumatic artificial muscles (PAMs) as soft, lightweight and compliant actuators have great potential in applications for the actuations of new types of robots and manipulators. The favourable characteristics of fluidic muscles, such as high power-to-weight ratio and safe interaction with humans are also very suitable during the process of musculoskeletally rehabilitating patients and are often used in making artificial orthoses. This technology, despite the problems of control relatng to nonlinear phenomena, may also have wide future applications within industrial and mechatronic systems. This paper presents several experimental systems actuated by PAMs, which have been designed as test models within the fields of mobile robots, mechatronics, fluid power systems and the feedback control education of mechanical engineering students. This paper first presents the design and construction of a four legged walking robot actuated by pneumatic muscles. The robot has a fully autonomous system with a wireless application platform and can be controlled using a cell phone. Then the paper describes the design and construction of the prototype of an actively-powered ankle foot orthosis. This orthosis device actuated by a single PAM is able to provide the appropriate functions required during the rehabilitations of patients and the loss of mobility. Then the paper focuses on the design and control of a ball and beam system with an antagonistic muscle pair for generating the necessary torque for beam rotation. This mechatronic balancing mechanism falls into the category of unstable, under-actuated, multivariable systems with highly nonlinear dynamics. The final section of the article presents the design and control of a single-joint manipulator arm with pneumatic muscle actuators that enable some new features for the controlled systems.

Control of Manipulator Using Pneumatic Muscles for Enhanced Safety

IEEE Transactions on Industrial Electronics, 2000

Safety of humans who work with robots is an important issue. Many studies have addressed related methods, but fundamental limits to meet safety requirements have been encountered owing to the absence of compliance in robot actuators. Pneumatic muscle (PM) is considered to be a basic actuator and offers the advantage of intrinsic elasticity to achieve joint compliance. In this paper, joint compliance actuated by PM is actively utilized to enhance human safety during collisions. To this end, the authors present a novel approach to control compliance and associated positions independently with no cross-performance effects using PMs. The proposed method is verified by experiments using a physical robot. In addition, methods to decrease damage from collisions between robots and humans due to operational faults are evaluated through experiments. The effectiveness of the proposed method is verified by measuring the impact impulse in collisions.

Measurements and simulation of a pneumatic muscle actuator for a rehabilitation robot

Simulation Practice and Theory, 1995

The performance of a pneumatic muscle actuator, invented by Jim Hennequin and used in a prototype wheelchair-mounted robot arm designed by the first author is reported. Experimental measurements were made of the output torque versus rotary motion and internal pressure. The torque available for a muscle of size 60 mm width by 90 mm length ranges from 1 to 15 Nm. The rotary stiffness of this muscle is 0.081 Nm/deg. A theory based on thermodynamic principles indicates that the efficiency of the pneumatic muscle actuator reaches a maximum of 67%. A simulation model of the dynamic behaviour of the muscle attached to the robot arm using one-dimensional flow theory was written in ACSL (Advanced Continuous Simulation Language). The resultant simulation gives good agreement to within f 5% of the experimental values. . 0928-4869/95/$09.50 0 1995 -Elsevier Science B.V. All rights reserved SSDI 0928-4869(95)00010-O 82 S. D. Prior, A.S. White / Simulation Practice and Theory 3 (1995) 81 -I I7 Several other wheelchair-mounted robotic systems have been developed in the past twenty years, notably by Spar Aerospace of Canada [32], the VA Medical Center of New York [ 191, the Jet Propulsion Laboratory of the California Institute of Technology and the University of Virginia.

Design of Wearable Power Assist Wear for Low Back Support Using Pneumatic Actuators

International Journal of Automation Technology

This research focuses on developing a safe, lightweight, power assist device that can be worn by people during lifting or static holding tasks to prevent them from experiencing Low Back Pain (LBP). In consideration of their flexibility, light weight, and large force to weight ratio, two types of pneumatic actuators are employed in assisting low back movement for their safety and comfort. Actuator A is an elongation-type pneumatic rubber artificial muscle that is installed in the outer layer of the garment. Its two ends are fixed on the shoulders and thighs. It can output contractile force, assisting the erector spinae muscles in the same direction. Compared to McKibben-type pneumatic rubber artificial muscle, the elongation type has a larger contraction rate. Actuator B is a layer-type of pneumatic actuator; it is composed of two balloons, and it is installed in the inner layer of the garment. By taking into account the biomechanic structure of the human spine, this device can provi...

Second generation pleated pneumatic artificial muscle and its robotic applications

Advanced Robotics, 2006

This paper reports on the second generation of the Pleated Pneumatic Artificial Muscle (PPAM) which has been developed to extend the life span of its first prototype. This type of artificial was developed to overcome dry friction and material deformation which is present in the widely used McKibben type of artificial muscle. The essence of the PPAM is its pleated membrane structure which enables the muscle to work at low pressures and at large contractions. There is a growing interest in this kind of actuation for robotics applications due to its high power to weight ratio and the adaptable compliance, especially for legged locomotion and robot applications in direct contact with a human. This paper describes the design of the second generation PPAM, for which specifically the membrane layout has been changed. In function of this new layout the mathematical model, developed for the first prototype, has been reformulated. This paper gives an elaborate discussion on this mathematical model which represents the force generation and enclosed muscle volume. Static load tests on some real muscles, which have been carried out in order to validate the mathematical model, are then discussed. Furthermore are given two robotic applications which currently use these pneumatic artificial muscles. One is the biped Lucy and the another one is a manipulator application which works in direct contact with an operator.

Pneumatic Muscle-Based Actuator for Industrial Robotic Applications

Proceedings of 2017 the 7th International Workshop on Computer Science and Engineering, 2017

The outstanding feature of the pneumatic artificial muscle is its high power to weight ratio vastly outperforming both pneumatic cylinder and DC motor. This feature is very important for using of pneumatic muscle-based actuators in industrial robotic systems where high forces and stiffness of mechanism are often required. The most common so far produced and used type of pneumatic artificial muscle is McKibben muscle and it is now made commercially available by different companies (e.g. Festo). In the paper there are described some of its characteristics and principles of control important for using as actuator for industrial robotic applications.