Research → Mechatronic systems → Pneumatically actuated inverted wedge → Experimental system descriptionThe experimental system consists of three primary components: the balancing mechanism, analog and digital interfaces, and digitally realized controller. The balancing mechanism is composed of a pneumatic cylinder and a rotating frame, a proportional valve as the control component, two rotational potentiometers as the slider position and the frame angle sensors. The double-acting rodless cylinder is by FESTO with the stroke L=600 mm and diameter d=12 mm. The proportional 5/3 control valve (FESTO type MPYE-5 1/8 HF-010B) can adjust flow-rate in the range -700 to 700 l/min by changing the spool position according to input voltage in the range 0 to 10 V. When input voltage is 5 V, all control edges are closed so that the flow rate to the cylinder chambers is zero. On this way, the linear motion x of the slider with mass m is controlled. The slider position x and the wedge angle q are sensed with rotational servo potentiometer produced by Spectrol. The electronic reference voltage card with ref-chip reduces the measured signals from potentiometer to required values. To detect differential pressure between two chambers, and also the supply air pressure, three pressure transducers SMC ISE4-01-26 were employed. The measured signals are passed to the Intel-based PC through data acquisition and control board (Advantech PCL-812PG) with 12-bit A/D converter. The control signal is computed within PC and passed to the proportional valve via 12-bit D/A converter. Control system design and experimental verification is performed in the Matlab/Real-Time Workshop program, which allows a rapid control system development and testing. |