James Doebbler

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This paper presents an improved Adaptive-Reinforcement Learning Control methodology for the problem of unmanned air vehicle morphing control. The reinforcement learning morphing control function that learns the optimal shape change policy is integrated with an adaptive dynamic inversion control trajectory tracking function. An episodic unsupervised learning(More)
Autonomous air refueling is an important capability for the future deployment of unmanned air vehicles, because it permits unmanned air vehicles to be ferried in flight to overseas theaters of operation instead of being shipped unassembled in containers. This paper demonstrates the feasibility of precise and reliable boom and receptacle autonomous air(More)
Testing and validation of flight hardware in ground-based facilities can result in significant cost savings and risk reduction. We designed a relative motion emulator for aerospace vehicles using omni-directional mobile bases which provide large 3 degree-offreedom motion, while Stewart platforms mounted atop these bases allow superposition of limited 6(More)
We are developing a mobile robot capable of emulating general 6-degree-of-freedom spacecraft relative motion. The omni-directional base uses a trio of active split offset castor drive modules to provide smooth, holonomic, precise control of its motion. Encoders measure the rotations of the six wheels and the three castor pivots. We present a generic(More)
We are developing a novel autonomous mobile robotic system to emulate full 6 degree of freedom relative motion at high fidelity. An omni-directional base provides large 3-DOF motion with moderate precision, while a micron-class Stewart platform on top provides high precision, limited 6-DOF motion. This multi-vehicle robotic system is designed to accommodate(More)
We are developing an autonomous mobile robotic system to emulate six degree of freedom relative spacecraft motion during proximity operations. A mobile omni-directional base robot provides x, y, and yaw planar motion with moderate accuracy through six independently driven motors. With a six degree of freedom micro-positioning Stewart platform on top of the(More)
We are developing an autonomous mobile robotic system to emulate six degree of freedom relative spacecraft motion during proximity operations. A mobile omni-directional base robot provides x, y, and yaw planar motion with moderate accuracy through six independently driven motors. With a six degree of freedom micro-positioning Stewart platform on top of the(More)
In this paper we explore cooperative manipulation of a flexible structure using a team of two nonholonomically-constrained, differentially-driven robots. Cooperative manipulation is achieved by tracking relative trajectories that are designed for both the nonholonomic nature of the platforms and path constraints limiting the deformation of the flexible(More)
Autonomous in-flight air refueling is an important capability for the future deployment of unmanned air vehicles, since they will likely be ferried in flight to overseas theaters of operation instead of being shipped unassembled in containers. This paper introduces a vision sensor based on active deformable contour algorithms, and a relative navigation(More)
This paper discusses the design and implementation of a series of system-wide simulation upgrades made to the Vehicle Systems and Control Laboratory in the Aerospace Engineering Department at Texas A&M University. The simulation system consists of a PCbased distributed simulation network comprised of a fixed-base full cockpit simulator and three additional(More)