CHANDRAYAAN-2 LANDER ACTUATOR PERFORMANCE TEST (LAPT PHASE-2)Home/Archives/ CHANDRAYAAN-2 LANDER ACTUATOR
The Lander Actuator Performance Test (LAPT) is one of the crucial tests required to be demonstrated for a successful soft and safe landing of Vikram (Chandrayaan-2 Lander). To carry out this test, an LAPT module which is a scaled down version of Vikram with all the required hardware was realised for testing in Earth environment. The reason for the scaling down is to compensate the effect of Earth’s gravity as compared to Moon’s gravity and to match the thrust generation of sea level Liquid Engines as compared to flight engines which will operate in vacuum environment. The module was tethered to a crane hook for conducting the test. To carry out this test, a special test facility was erected at ISRO Propulsion Complex, Mahendragiri. The objective of the test was to assess the closed loop integrated performance of Sensors, Actuators and Navigation, Guidance & Control (NGC) and guidance algorithms below 100 m height. Three tests have been conceived as part of LAPT Phase-2 activities to demonstrate these objectives. First test was conducted to demonstrate Vertical Descent while second Test was conducted to demonstrate Hovering. The third and final test was successfully conducted to demonstrate re-targeting in a Parabolic Trajectory, on 25th Oct 2018 at ISRO Propulsion Complex, Mahendragiri. This test demonstrated the capability of the NGC system of Vikram to meet the mission requirement of safe, soft and precise landing on the lunar surface by steering the module horizontally as well as vertically down to a pre-defined target. With this, all the tests have been completed successfully. This is a major milestone accomplished in Chandrayaan-2 Lander.