INDIAN INSTITUTE OF TECHNOLOGY MADRAS
Department of Engineering Design
Robotics Laboratory
TECHNOLOGY DEVELOPMENT OF PROPORTIONAL
SOLENOID VALVE FOR SPACE APPLICATIONS
Objective
Indigenous development of proportional solenoid valve for space applications is the major objective of the project. Necessary
know how for the same will be developed and transferred to ISRO. Prototyping of a normally closed type proportional valve
will be carried out by ISRO with the technical assistance from IIT MADRAS.
Design Approach
A proportional valve can take intermediate positions depending upon the strength of the electric signal. Proportional valves
has to be designed by modifying its parts like plunger, spring etc. For the valve to control at intermediate positions the
force/stroke curve should be constant throughout the displacement. One method to make the force/stroke constant throughout
the stroke length is making the air gap between the plunger and magnet constant. By tapering the plunger the air gap
between the plunger and magnet can be made constant. So far the design of the solenoid valve a plunger with taper angle is
made. For smaller angles, the force will decrease gradually from the beginning to end of the stroke because the plunger will
saturate early in the stroke. For larger angles, the force will increase gradually from beginning to end of the stroke for larger
angles because the plunger will not saturate early in its stroke. So to obtain constant force through out the stroke a medium
angle is used.
Design Requirements and Specification
Following are the brief specification for the design of proportional
solenoid valve
Max stroke=0.7mm
Solenoid force=50N
Operating range of current (for 5kg load)=500milliampere(max)
Plunger diameter=20 to 22 mm
Solenoid wire gauge,(preferred sizes)=AWG26,28,30,32,34&37
Solenoid materials
AISI 446(magnetic) and AISI304L (non magnetic)
3D Model of the Solenoid Simulation of Solenoid
Dynamics
Mathematical Modeling and Analysis
Time Response
Force vs Air gap
Force vs Displacement
Flux and Force
Analysis
Experimental Verification
SOLENOID
VALVE
DISPLACEMENT
SENSOR
FORCE SENSOR
DATA
ACQUSITION
SYSTEM
Researchers :
Dr. T. Asokan, Rakesh Sourirajan, Manoj M
COMPUTER