About PS4 engine:
- It is the uppermost stage of Polar Satellite Launch Vehicle (PSLV), comprising two Earth storable liquid engines.
- It uses a bipropellant combination of nitrogen tetroxide as the oxidizer and monomethyl hydrazine as the fuel, developed by Isro’s Liquid Propulsion Systems Centre.
- The same engine is also used in the Reaction Control System (RCS) of the first stage (PS1) of PSLV.
- ISRO redesigned the conventionally manufactured PS4 engine to make it compatible with additive manufacturing techniques and this innovative approach, known as Design for Additive Manufacturing, has yielded remarkable advantages.
What is Additive Manufacturing?
- It is also known as 3D printing which is an emerging technology that is rapidly transforming manufacturing processes worldwide.
- It creates 3-dimensional objects by successively layering materials under computer control.
- It involves layering materials like plastics, composites, or bio-materials to create objects that range in shape, size, rigidity, and colour.
- Compared to traditional subtractive techniques, 3D printing offers immense design flexibility, reduced waste, and the ability to produce complex geometries.
Q1: What is a Geosynchronous Satellite Launch Vehicle (GSLV)?
It is a space launch vehicle designed, developed and operated by the ISRO to launch satellites and other space objects into Geosynchronous Transfer Orbits (GTO).
Source: ISRO’s engine design saves raw material, time
Last updated on January, 2026
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