Solar Array Mechanisms for Indian Satellites, APPLE, IRS and INSAT-IITS SAMIRAN DAS & I. SELVARAJ Summary Large area rigid panel deployable and trackable solar arrays are widely used in present-day operational satellites. Three solar array mechanisms of this type for Indian spacecraft are described, one of which has already undergone flight verification. The other two mechanisms are of higher complexity and being readied for launch in the immediate future, as essential for providing India's space services in communication and remote sensing fields. Design approach, test programme and implications of test modelling towards achieving the design goal are discussed. Performance characteristics of the solar array mechanisms achieved after flight verification and qualification tests are also highlighted in the paper. 1. Introduction To meet the ever increasing power needs of spacecraft for various applications, the deployable solar array is the commonly adopted design strategy. Here the fundamental requirement of a reliable mechanism to deploy the arrays needs particular emphasis. This paper describes the solar array mechanisms of Indian Space Research Organisation's (ISRO) three satellites, one of which is already launched successfully for demonstrating space communications capability. The other two are scheduled to be launched shortly also under ISRO's communications and remote sensing programmes. The mechanisms have grown in complexity for a 2-panel system in APPLE (Ariane Passenger Payload Experiment), to a 6-panel system in IRS (Indian Remote Sensing Satellite) and then to a more complex one-sided panel system with balancing sail boom in INSAT-IITS (Indian National Satellite). This paper provides the details on how the system design has been evolved capable of meeting the individual mission requirements, the testing and qualification features, problems encountered during the qualification phase, along with flight performance of one of the mechanisms. 2. Solar Array Mechanism for APPLE The first Indian 3-axis body stabilized geostationary communication satellite, APPLE, was an experimental venture. With 670 Kg as lift-off mass and 380 Kg as dry mass the satellite's power requirements were derived from its two driven and deployable solar arrays, which folded and deployed in accordion fashion. Samiran Das, Vikram Sarabhai Space Centre, Trivandrum, India. I. Selvaraj, ISRO Satellite Centre, Bangalore, India.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==