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The pressure switch. (a) The pressure switch. (b) The proportional pressure regulator. (c) Comparison with proportional pressure regulator.  

The pressure switch. (a) The pressure switch. (b) The proportional pressure regulator. (c) Comparison with proportional pressure regulator.  

Source publication
Conference Paper
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Pneumatic muscle has many advantages such as elasticity, high power and structural similarity to a living thing's muscle. There has been many researches to control robot actuated by pneumatic muscles, but conventional theories are hard to apply on real robot plants because of their assumptions and disregards of pneumatic muscle's physical aspects l...

Contexts in source publication

Context 1
... a set of equipments of encoder and pressure switch shown in fig.2 -(a) is enough to control PM's inside pressure and to replace a proportional pressure regulator. Usually robot joint is a revolute type with circular motion. Encoder can get the information of current angular position of joint. The dif- ference of position means the angular velocity of joint and the difference of angular velocity means the ...
Context 2
... pressure switch is really small one. The dimension of outer square of it is 33mm × 57mm × 10mm (width × height × depth), which is about 1/30 volume of proportional pressure regulator. The comparison between them is shown in fig.2 - (c). When we implement robot, encoders are basically attached to it to get information about angular position, so actually only pressure switch is substitute of proportional pressure regulator. The operation of pressure switch is simple. It has three kinds of mode, turn on, turn off and power off. When the pressure switch is turned on, it ...

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Citations

... These control schemes are based on first and second order sliding mode control methodology. In [6], a new control method is proposed to overcome the space problem due to the implementation of actual PAM robot controlled by proportional pressure regulator. The proposed controller is synthesized based on a set of small encoders and pressure switches to be replaced by the commercial proportional pressure regulator, whose size is not suitable to be applied on stand-alone robot. ...
... Pneumatic artificial muscle[3,6] ...
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... This structure does not permit one PAM in the pair to contract and relax unless another PAM inflation causes the first PAM to deflate. However, only one motor is sufficient to perform the desired movement in traditional actuators [5]. One other main problem in PAMs is the difficulty to control them, since they are highly time varying and nonlinear and they involve uncertain parameters. ...
... Moreover, the PAM-actuated system is merely a hanging mass actuated by PAMs. Choi et al.,in [5], proposed a control technique for a PAM-actuated robot to replace a proportional pressure regulator (PPR) by a controller composed of a set of small encoders and pressure switches to solve the space problem due to the implementation of PPR. The results based on experimental tests show that the new controller could save space, but at the price of precision degradation. ...
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... The initial PAMs were mostly home-made and thus repeatability and reproducibility were severely limited. With the availability of commercial PAMs from companies such as Festo AG & Co. KG (Anh et al., 2008;Chang et al., 2006;Situm and Herceg, 2008;Choi, et al., 2006;Zhang, Christopher, & Kawamura, 2008) and Bridgestone (Pack, Yang, Chen, Zhang, & Dong, 1997), more reliable, consistent and cheaper PAMs can be obtained. ...
... Once the set point has been reached, both valves are closed to maintain the position or force. In addition, the physical size of the HSV is significantly smaller than the PPR (Choi et al., 2006). However, the high speed switching on the HSV is rather noisy and may be a hindrance in robotic applications. ...
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... The initial PAMs were mostly home-made and thus repeatability and reproducibility were severely limited. With the availability of commercial PAMs from companies such as Festo AG & Co. KG (Anh et al., 2008;Chang et al., 2006;Situm and Herceg, 2008;Choi, et al., 2006;Zhang, Christopher, & Kawamura, 2008) and Bridgestone (Pack, Yang, Chen, Zhang, & Dong, 1997), more reliable, consistent and cheaper PAMs can be obtained. ...
... Once the set point has been reached, both valves are closed to maintain the position or force. In addition, the physical size of the HSV is significantly smaller than the PPR (Choi et al., 2006). However, the high speed switching on the HSV is rather noisy and may be a hindrance in robotic applications. ...
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The design and development of an offline self organizing fuzzy controller for a pneumatic artificial muscle (PAM) is discussed in this paper. This inherently compliant soft actuator is intended as the driving component in a mobile, lower limb, assistive/rehabilitative orthotic device. Accurate control using classical control approach is difficult due to the compressibility of gas and the nonlinear elasticity of the PAM bladder. To overcome this, a self-organizing fuzzy controller is proposed and tested in simulation. Results for step, ramp and sinusoidal inputs exhibit excellent tracking capability. The rise time for a 17% contraction (knee contraction angle of 60° - upper limit of average knee contraction during walking) step input is 0.2s, while the steady state error is well below 2%.
... Here it is supposed that it is almost impossible to assure both high precision and high elasticity generally though there were many great researches [6][7][8][9]. Some robot needs high precision and low elasticity like industrial application, but some robot need high elasticity without considering of high precision in millimeter unit like human robot interaction (HRI) application. ...
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