AE Presents: Dr. Alex Ghosh from the University of Illinois at Urbana-Champaign

Alex Ghosh

University of Illinois at Urbana-Champaign

Thursday, November 16 @ 3:30 p.m.
Guggenheim 442

While basic orbit determination is a well understood problem, determining a full solution to the pose estimation and surface feature map of a target resident space object poses a greater challenge. Most orbit determination approaches suppose the use of active radar, frequently from the ground, but when the system making the determination is itself a spacecraft in a nearby orbit, traditional approaches are insufficient. This problem is further complicated when the chase spacecraft performing the determination is only equipped with a passive, monocular sensor such as a camera, rather than active radar or binocular vision. Initially a Rao-Blackwellized Particle Filter was implemented, however this classic approach was not able to converge within the desired timeframe and system observability. A new algorithm was developed which achieves the desired solution by using nonlinear programming applied to bundle adjustments over time, while absorbing core concepts from the simultaneous location and mapping field. An extended Kalman filter is used at long distance to determine the location of the target’s center-of-mass during approach phases while at long ranges. This algorithm is ultimately capable of on-board pose and orbit determination of its target, and has applications for automated spacecraft servicing, and proximity operations at near Earth asteroids.

Dr. Alexander Ghosh is an adjunct research assistant professor at the University of Illinois and a senior scientist at CU Aerospace. Dr. Ghosh received his PhD in Aerospace Engineering in 2013 from the University of Illinois, his Master’s Degree in Aerospace Engineering from University of Illinois in 2009, and his Bachelor’s of Aerospace Engineering from Carleton University in 2007. He is a project manager for the University of Illinois’ Illinisat-2 program, and oversees the systems integration and testing for five upcoming missions, and has been PI for multiple successful research and technology development programs. In 2013, he was selected as a Research Fellow at the Center for Space Nuclear Research. During the summer of 2008, he attended the International Space University Space Studies program. His research focuses on high fidelity trajectory propagation and applications of parallel processing to numerical optimization and space navigation problems, as well as small satellite systems design.

Event Details


  • Thursday, November 16, 2017
    3:30 pm - 4:30 pm
Location: Guggenheim Building Room 442