On the implementation of stiffness control on a manipulator using rubber actuators

Zong, Guanghua; Liu, Rong

doi:10.1109/icsmc.1995.537755

Cited by 6 publications

(3 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such torques can be provided by a biologically inspired antagonistic configuration, in which two air muscles would produce torque as a difference of applied pulling forces. Furthermore, the redundancy in actuation allows to adjust the stiffness of the joint in an open loop manner by air muscle co-contraction [11]. The advantage of co-contraction instead of stiffness control (through negative position feedback) is noteworthy as it overcomes the closed loop gain limitations related to transmission delay and bandwidth [12].…”

Section: Introductionmentioning

confidence: 99%

Air Muscle Controller Design in the Distributed Macro-Mini (DM²) Actuation Approach

Sardellitti

Park

Shin

et al. 2007

2007 IEEE/RSJ International Conference on Intelligent Robots and Systems

View full text Add to dashboard Cite

Recently, on the base of Distributed Macro-Mini Actuation approach (DM 2 ), a new robotic manipulator with hybrid actuation, air muscles-DC motor, has been developed. Among existing actuators, the hybrid actuation employs air muscles because they represent an advantageous tradeoff of performance and safety, due to their power/weight ratio and inherent compliance. The air muscles, however, are limited in bandwidth and their behavior is highly nonlinear. In order to overcome these limitations, the paper presents a torque control strategy based on a pair of differentially connected force-controlled air muscles. This controller was implemented and evaluated on a single joint testbed, first by itself and then as macro component into the Macro-Mini control strategy.

show abstract

Section: Introductionmentioning

confidence: 99%

Air Muscle Controller Design in the Distributed Macro-Mini (DM²) Actuation Approach

Sardellitti

Park

Shin

et al. 2007

2007 IEEE/RSJ International Conference on Intelligent Robots and Systems

View full text Add to dashboard Cite

show abstract

“…Applications of artificial muscle technologies have received considerable attention in research and development over the years. Particularly for robotic systems, a leading artificial muscle technology has been that of pneumatic artificial muscles (PAMs) for their marked operational similarity to natural muscle, compliance, high force to weight ratios, and high fatigue life [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Specifically, PAMs, or McKibben actuators, are uni-directional devices that generate a pulling force in response to pressure-induced volume change.…”

Section: Introductionmentioning

confidence: 99%

“…Additional work has gone into influencing the passive and active stiffness of the system by varying the bias pressure of the system, that is, the starting pressure to which both PAM are inflated, with the general understanding that higher bias pressure equates to higher joint stiffness. This topic is of great interest in the robotics field and many analyses exist to aid in joint stiffness design [3,7,13,16]. Finally, most antagonistic PAM applications, with the exception of some recent aerospace applications [18,20], have operated from a pre-contracted state in order to increase range of motion.…”

Section: Introductionmentioning

confidence: 99%

Mechanism and bias considerations for design of a bi-directional pneumatic artificial muscle actuator

Vocke¹,

Kothera²,

Wereley³

2014

Smart Mater. Struct.

View full text Add to dashboard Cite

Pneumatic artificial muscles (PAMs), or McKibben actuators, have received considerable attention for robotic manipulators and in aerospace applications due to their similarity to natural muscles. Like natural muscles, PAMs are a purely contractile actuator, so that, in order to produce bi-directional or rotational motion, they must be arranged in an agonist/antagonist pair, which inherently limits the deflection of the system due to the high parasitic stiffness of the antagonistic PAM. This study presents two methods for increasing the performance of an antagonistic PAM system by decreasing the passive parasitic torque, rather than increasing the active torque. The first involves selection of the kinematic mechanism geometry, and the second involves the introduction of bias into the system, both in terms of PAM contraction and passive (antagonistic) PAM pressure. It was found with the proper selection of design parameters, including mechanism geometry, PAM geometry, and bias conditions, that an ideal actuator configuration can be chosen that maximizes deflection for a given arbitrary loading. When comparing a baseline design to an improved design for a simplified case, a nearly 50% increase in maximum deflection was predicted simply by optimizing mechanism geometry and bias contraction. These results were experimentally verified with quasi-static testing that showed a 300% increase in actuator deflection over the baseline design.

show abstract

Independent stiffness and force control of antagonistic pneumatic artificial muscles joint

Zhao

et al. 2017

2017 2nd International Conference on Advanced Robotics and Mechatronics (ICARM)

View full text Add to dashboard Cite

With the extensive development of the robotics research, the actuator source of the robot has been extensively studied. The traditional motor and cylinder drive have big stiffness, it is easier to hurt the operator. The PAM is more compliance, and it have high force-to-weight ratio and safety[1]. Based on these characteristics, researchers take in-depth study of PAMs. PAM can generate contraction force by compressing gas. It is used in medical, rehabilitation and robotics[2-5]. The first woven PAM was designed by American physician Joseph L. McKibben in the 1950s[6]. In the last decade, international scholars have got some achievements[7]. Ching-ping Chou et al. established the static model of McKibben type PAM[8]. Based on the mathematical model, Repperger et al. designed a nonlinear feedback controller to control the single PAM system[9]. However a single PAM system can't provide simultaneous tension and pressure. So, Caldwell et al. designed a PID controller for controlling the position of a group of antagonistic PAMs joint[10]. Bong-Soo Kang analyzed force characteristic of antagonistic PAMs joint by sliding control[11]. In order to provide compliance to enhance the intrinsic safety of human or robot interaction, several researchers have developed variable stiffness of PAMs. The modulation of actuator output stiffness and force can serve several purposes in robotic applications.

show abstract

On the implementation of stiffness control on a manipulator using rubber actuators

Cited by 6 publications

References 7 publications

Air Muscle Controller Design in the Distributed Macro-Mini (DM²) Actuation Approach

Air Muscle Controller Design in the Distributed Macro-Mini (DM²) Actuation Approach

Mechanism and bias considerations for design of a bi-directional pneumatic artificial muscle actuator

Independent stiffness and force control of antagonistic pneumatic artificial muscles joint

Contact Info

Product

Resources

About

On the implementation of stiffness control on a manipulator using rubber actuators

Cited by 6 publications

References 7 publications

Air Muscle Controller Design in the Distributed Macro-Mini (DM2) Actuation Approach

Air Muscle Controller Design in the Distributed Macro-Mini (DM2) Actuation Approach

Mechanism and bias considerations for design of a bi-directional pneumatic artificial muscle actuator

Independent stiffness and force control of antagonistic pneumatic artificial muscles joint

Contact Info

Product

Resources

About

Air Muscle Controller Design in the Distributed Macro-Mini (DM²) Actuation Approach

Air Muscle Controller Design in the Distributed Macro-Mini (DM²) Actuation Approach