Pneumatic elements are extensively used in process control, machine control, design of robotic manipulators, etc. The objective of this trainer is to demonstrate how a Microprocessor controlled system, can control actuation of mechanical elements in the field of Pneumatics. Operating sequences can be changed by a mere change in program. Many experiments can be conducted using Pneumatic Trainer. Pneumatic trainer is an experimental instrument. It is intended to use this trainer, to study Fluidics by experimentation. This trainer contains pneumatic actuators and electronic transducers. These devices provide opportunity to study and experiment how industrial applications are working. These working principles are applicable to high-pressure pneumatic and hydraulic components. This trainer introduces some of the important types of fluid control devices, and explains how they are functioning.

The controller provides facility to program for any specific function, like holding a job and riveting, move a job to the next place, change a sequence by observing the status of a feedback transducer, change time between two successive operations etc. It is necessary to note that, the above functions can be achieved by appropriately programming the controller. This trainer is one part, while the other is a controller. This trainer can be connected to any one of the following trainers as controllers. They are; a) Computer applications trainer, Model DAS-1 which is connected to an IBM PC/XT/AT Pentium computer, or b) with 96 line TTL I/O add-on card, Model IBR-1 which is connected to an IBM PC/XT/AT Pentium computer, or c) Microprocessor Trainer MPT-85. Programs are supplied in BASIC, when connected to the computer or in mnemonic language when connected to Microprocessor trainer.

Features:

• The electronic interface devices used in this trainer are TTL compatible.
  
• Good experimental / demonstration training aid in FLUIDICS, or instrumentation laboratory.
  
• Can be used as an excellent output element in FEEDBACK CONTROL system design, as used in machine control like NC/CNC machines.
  
• Programmable in high level languages like BASIC, TURBO PASCAL, C, ASSEMBLY, or even in Machine language etc. as long as the support I/O instructions.
  
• Good documentation with experimental programs, and program listings in BASIC.
  
• Useful in engineering colleges, Polytechnics, Training Establishments, R/D Laboratories, Defense Laboratories etc.
  
• It is possible to accomplish the following functions.
  
• Study of controlling the movement of pistons in the power cylinders.
  
• Study and experiment BOOLEAN functions like AND, OR, NOT, EX-OR, NAND, memory etc.
  
• Feedback control using built-in transducers (sensors) as feedback elements.
  
• Timing between the movement of two or more pistons.
  
• Variable time sequence.
  
• Programming the sequence of actuation of pistons.
  
• Design Inter-locking programs.
  
• Implement your own logic system, with the available input output elements.
  
• To some extent, this becomes your prototype development instrument.
  
• In addition to the above, using some of our external experimental modules, the trainer becomes more versatile FLUID POWER TRAINER.

A sample program is illustrated here, to explain how pneumatic cylinders are programmed in time domain. In this example, each piston extends and retracts with a time delay in a cyclic order. The operation repeats again and again, unless program execution is aborted.

10 port &H830E: REM "Set the port number
20 Delay = 600 REM " Set a delay period. Larger the delay number, longer the time between two successive operations
30 OUT PORT, 1: REM "Cylinder A's piston extend
40 FOR I=0 to delay: Next I
50 OUT PORT, 2 : REM" Holding current on D0 piston removed by applying a logic '0' and a logic'1' applied on D1 piston consequently A-piston RETRACTS. Strictly, this is not permitted. There should be some time delay, between switching OFF extending piston and switching ON retract piston.
60 FOR I = 0 TO DELAY: NEXT I
70 OUT PORT 4: REM "piston - A retract. Piston-B extends
80 FOR I = 0 DELAY: NEXT I
90 OUT PORT, 8: REM "Piston -B retracts
100 FOR I=0 TO DELAY: NEXT I
110 OUT PORT, 16: REM" Piston C extend
120 FOR I = 0 DELAY: NEXT I
130 OUT PORT, 32: REM" Piston-C retract
140 FOR I = 0 TO DELAY: NEXT I
150 OUT PORT, 64: REM "Piston -D extend
160 FOR I = 0 TO DELAY: NEXT I
170 OUT PORT, 128 : REM" Piston-D retract
180 FOR I = 0 TO DELAY: NEXT I
190 GOTO 30: REM " Indefinite loop. Go and execute the same again and again

Specifications:

• 40mm bore x 5/8" pistons. 4Nos.
  
• 4-way-5 port double acting solenoids. 4 Nos., Mufflers. 8Nos.
  
• 3/8" Filter Line Regulation unit. 1 No
  
• LED indicator for piston status. 8 Nos.
  
• Optical transducer. 1 No.
  
• Proximity sensor (metal detector). 1 No.
  
• Bi-level water level transducer. 1 No
  
• All elements mounted on 3' x 3' inclined stand, standing at a height of 5'.
  
• TTL compatible logic interface provided.
  
• Dedicated DC power source provided.
  
• Note: Microprocessor trainer MPT-85 or IBM PC add-on card model IBR-1 or Computer Applications Trainer, Model DAS-1 is required.
  
• Controllers are not included with this instrument.

Note: the user must provide Compressed air inlet pressure of 6Kg/cm2. We recommend ELGI make compressor of Model 105B, 230V AC single Phase.