India lunar mission Chandrayaan-3 eyes moon with enhanced capacity; launch on July 14

The spacecraft is programmed to handle failures and ensure a controlled landing at the required speed and rate, said ISRO chairman S Somanath.

• Shubham
• 10 July, 2023

Follow Us

By: Shubham Ghosh

CHANDRAYAAN-3, India’s upcoming lunar mission, is equipped with enhanced features to ensure a successful landing on the moon. The mission, scheduled for launch on July 14, is a follow-up to Chandrayaan-2, which experienced a crash-landing in 2019 due to a software glitch. To overcome previous challenges, the Indian Space Research Organisation (ISRO) has adopted a “failure-based design” approach for Chandrayaan-3, focusing on identifying potential failures and implementing measures to mitigate them.

ISRO chairman S Somanath explained that the design of Chandrayaan-3 considers various failure scenarios such as sensor failure, engine failure, algorithm failure, and calculation failure.

The spacecraft is programmed to handle these failures and ensure a controlled landing at the required speed and rate.

Somanath provided insights into the issues faced during Chandrayaan-2, including the higher-than-expected thrust developed by the engines responsible for reducing velocity. The accumulation of errors and limitations in the craft’s ability to handle rapid turns due to software constraints were additional contributing factors to the landing failure.

In response to these challenges, ISRO has made several improvements for Chandrayaan-3. The landing site area has been expanded from 500m x 500m to four kilometers by 2.5 kilometers, providing flexibility and reducing the need to target a specific point. The spacecraft is equipped with more fuel, enabling better travel capabilities and the ability to handle dispersion or divert to an alternate landing site. The Vikram lander now has additional solar panels on different surfaces to ensure power generation, regardless of its landing orientation.

To address potential landing issues, the vertical velocity component has been increased from 2 m/s to 3 m/s. Extensive testing has been conducted, including flying the spacecraft over various terrains using a helicopter to assess its ability to withstand vibrations. The landing processes have been evaluated using cranes, and new simulation test beds have been developed to analyse failure scenarios.

(With agency inputs)