Case Study

Design and Engineering of Crew Module Recovery Model (CMRM) for ISRO's Gaganyaan Space Mission

Design, Development and Fabrication of Crew Module Recovery Model

Background

The Gaganyaan project of ISRO envisages demonstration of human spaceflight capability by launching astronauts to an orbit in space for a short mission and bring them back safely to earth, by landing in Indian sea waters. Safe recovery of the crew is of paramount importance and must be carried out with the minimum lapse of time. It was for the first time ISRO has outsourced the mechanical design and development assignment including fabrication, of a critical system to an external partner.

For this mission, a dedicated module called Crew Module Recovery Modal (CMRM) was conceptualized. CMRM is a functional structure used for testing and practicing crew module recovery procedures. It simulates the mass, dimensions, and center of gravity of the actual crew module.

Challenge

This project pushed our engineering expertise in two key areas. First, the design itself was incredibly complex. The CMRM needed to simulate multiple systems and components, which meant we had to create a multifaceted design. This demanded innovative problem-solving and a deep understanding of engineering principles to ensure everything worked together seamlessly.

Secondly, we faced tight deadlines. We needed to not only design the CMRM but also fabricate it within a short timeframe. This meant efficiently coordinating with multiple vendors, managing fabrication reviews, and ensuring the smooth logistics of material transportation and distribution. Achieving the precise Center of Gravity (CG), and the design of the lifting lugs to withstand 11-ton load were the key design challenges.

Solution

Tata Elxsi designed, developed and installed a full-scale Crew Module Recovery Model (CMRM) with a mass of 4500 kg and dimensions of 2650 mm in height and 3100 mm in shoulder diameter to facilitate effective training for the recovery crews. Titanium and SS316 were utilized as construction materials to realize this model. In order to overcome the design challenge of Lighting Lugs, high strength grade 5 titanium was used for the lifting plates and lifting pins.

This model was designed to simulate the Form, Mass, CG, and buoyancy. A volume simulation of the entire apex system was additionally performed. This method also made it possible to gain exposure to better materials and enhance production abilities because these models are rarely made in significant quantities. A system of adjustable counterweights was created to achieve the precise CG location. This also provided us the ability to adjust the CG position when required.

In addition to designing the CMRM, Tata Elxsi also designed the Ground Support Fixture (GSF), a supporting framework that allows the model to be safely stored and transported to the designated location.

Impact

Tata Elxsi was able to meet the stringent timeline of 6 months for designing, developing and fabrication a fully functional prototype. We also have the full program ownership for the model.

We focused on design robustness and functionality from the beginning of the process, knowing how important the product was, in order to reduce risks and maximize performance. We guaranteed the product's structural integrity through routine quality inspections and structural analysis.

Where are we now

To train the recovery teams, two recovery models (CMRM and GSF) were given to the navy training teams at Kochi and Visakhapatnam. The Indian Navy and ISRO began the second round of crew recovery training on July 20, as reported by TOI. A total of 25 successful trials have been carried out at Vishakhapatnam and Kochi Naval bases.

Tata Elxsi has also become qualified in bidding for the phase 2 activities like interior fabrication and design.