Name: Gaurav Waratkar
Affiliation: Indian Institute of Technology Bombay
Conference ID : ASI2022_425
Title : Daksha: Structural design, simulations and testing of the payload
Authors : Gaurav Waratkar (IIT Bombay), Aditi Marathe (IIT Bombay), Srividhya S. (IIT Bombay, SNS College of Technology), Suresh G. (IIT Bombay), P J Guruprasad (IIT Bombay), Salil Kulkarni (IIT Bombay), Deepak Marla (IIT Bombay), Rakesh Mote (IIT Bombay), Varun Bhalerao (IIT Bombay)
Abstract Type: Poster
Abstract Category : Instrumentation and Techniques
Abstract : Daksha is a proposed all-sky high energy transient monitoring satellite system. With high energy, medium energy, and low energy detector sets, it is designed as a pair of quasi-hemispherical satellites in a 650 km near-equatorial Low Earth orbit. Each payload has a large surface area of about 2 sq.m. for mounting over 300 detectors, making it a challenge to design the payload structure within reasonable mass bounds. Also, the payload is subjected to intense vibrations during launch which imposes constraints on the minimum natural frequency that the payload can have in order to avoid catastrophic vibrations due to resonance. Thus, for design qualification and development of the project, structural analysis was critical from the early phases, with our primary focus being on optimizing the weight and understanding the vibration response of the payload. We report on extensive simulations that established a preliminary configuration of the satellite, where we performed modal vibration, static structural, sine-vibration, and random vibration analyses, and also studied the feasibility of manufacturing different satellite configurations. For certain cases, we investigated different materials with different combination properties. These simulations and the resulting optimizations improved the fundamental vibration frequencies of our payload subsystems to meet the required thresholds of above 100 Hz, without compromising significantly on the weight (even reducing it by as high as 60% in certain cases). We also performed vibration tests on payload subsystems that successfully verified our modal simulations. Future optimizations to the payload and further validating testing are also discussed.