Enabling Moving Target Hand-off in GPS-Denied Environments

Sponsor: Systems & Technology Research (AF STTR)

Future conflicts in contested environments will require coordination between teams of manned and unmanned platforms performing ISR tasks. Coordinating ISR tasks is much more challenging in these conditions as GPS cannot be reliably depended upon. Consider the ISR task of handing off a tracked target from one platform to another. Reliably performing this task requires at a minimum an estimate of the relative pose (change in 3D position and orientation) between the two ISR sensors. In the GPS-enabled case, this is trivial to compute from the current GPS-INS position/attitude estimates on each of the platforms. In the GPS-denied case, however, this task becomes much harder.

The role for WVU IRL in this project is to develop a a method for estimating the relative pose of a pair of Unmanned Aerial Vehicles (UAV) using noisy measurements from ranging radios and each aircraft’s on board navigation system. In this method, there is no prior information needed about the relative pose of each UAV. During the estimation of the relative pose of two traveling UAVs, only a single range measurement between UAVs is needed at each location. To augment this limited information, motion is used to construct a graph with the range measurements and displacement in position over multiple locations. First, the analytical solution is derived for the pose from the constructed graph assuming the system is free of noise. Then, the relative heading and bearing are estimated from noisy range measurements and the displacement in position using nonlinear least squares.

Publications

1. Strader, J., Gu, Y., Gross, J., De Petrillo, M., Hardy, J., "Cooperative Relative Localization for Moving UAVs with Single Link Range Measurements," Accepted, IEEE/ION PLANS, Savannah, Georgia, Apr 2016.
2. Hardy, J., Strader, J., Gross, J., Gu, Y., Cabezas, R., Keck, M., Douglas, J., Taylor, C., "Unmanned Aerial Vehicle Relative Navigation in GPS Denied Environments," Accepted, IEEE/ION PLANS, Savannah, Georgia, Apr 2016.