Research

Principal Investigators: Dr. Dan Stilwell, Dr. Stefano Brizzolara
Sponsor: Office of Naval Research (ONR)

Description: We are developing a small autonomous underwater vehicle (AUV) that can tow a payload whose drag is many times larger than that of the AUV. The payload trajectory is precisely controlled so that the payload arrives at a desired location with a desired horizontal orientation at a desired time. The AUV presents a number of design challenges. For example, the propulsion system must provide many times more thrust than needed for the AUV alone, but without cavitation or excessive roll-moment. Likewise, the control system requires unconventional control affectors in order to meet maneuvering objectives while towing a large payload. The outside diameter is 4.875" so that it can be deployed from existing infrastructure for A-size systems.

Principal Investigators: Stilwell and Brizzolara
Sponsor: Office of Naval Research (ONR)

Description: In collaboration with colleagues at Penn State, we will formally examine a wide array of design trade-offs for an autonomous vehicle system that can operate both in air and in water. We seek to develop overall design guidance as well as tools that can be used to map functional requirements, such as endurance, payload size/weight/power, etc, to a specic candidate vehicle. In addition, we will contribute to the design, fabrication, and testing of specic autonomous vehicles that operate in a marine environment. We will develop a low-noise propulsion system for an existing quad-rotor unmanned air vehicle, as well as autonomous vehicles that operate in both air and water. In collaboration with our colleagues at Penn State, we will develop an entirely new hybrid autonomous vehicle that is able to operate in air and underwater. We will focus on the vehicle's propulsion subsystem as well as other subsystems related to operating underwater.

Principal Investigators: Dr. Craig Woolsey
Sponsor: Office of Naval Research (ONR)

Description: The forces and moments acting on a submerged vessel moving near the free surface are strongly influenced by external waves and also by the waves generated by the vessel’s own motion. A Lagrangian mechanics model that captures the essential physics of maneuvering in a seaway would enable the design of model-based controllers that enable more precise and effective motion control.

Principal Investigators: Dr. Craig Woolsey
Sponsor: National Science Foundation (NSF)

Description: While bound by the same physical laws that govern engineered systems, creatures exhibit astonishing capabilities for speed, agility, stealth, robustness, and efficiency. Focusing on the case of pisciform (“fish-like”) locomotion, this effort aims to develop low-dimensional, state space models for unsteady flow effects and to incorporate these models in a geometric control framework that enables the design of optimum morphologies and gaits.

Principal Investigators: Dr. Dan Stilwell, Dr. Craig Woolsey, Dr. Pratap Tokekar
Sponsor: Institute for Critical Technology and Applied Science (ICTAS)

Description: There is an extraordinary demand for inspection services of civil infrastructure. Bridges, high-rise buildings, off-shore oil gas facilities, and chemical processing plants, to name a few, all have regulatory requirements for periodic inspection to evaluate current conditions, deterioration rates, and potential safety issues. Due to the repetitive nature, limited access, and need for accuracy, many of the inspection tasks are ideal applications for autonomous vehicles. The goal of this project is to jump-start the new and highly lucrative industry of autonomous infrastructure inspection by solving key fundamental technical challenges, and by working with industry to develop safe, reliable, and commercially viable autonomous inspection systems. Our approach encompasses inspection tasks that are dull, difficult, and/or dangerous for human inspectors, and for which there is strong economically-justied commercial pull for autonomous systems to replace human inspectors.

Principal Investigators: Stilwell
Sponsor: Office of Naval Research (ONR)

Description: We address fundamental challenges in collaborative mapping for a variety of underwater mapping applications. We seek new decentralized control policies that can be computed in real-time, require minimal inter-vehicle communication, and that enable a team of cooperating autonomous underwater vehicles (AUVs) to jointly maximize a rigorously defined measure of mapping performance. The principal challenge of our project is to determine minimal communication requirements. We will test our results in the field by assisting with sea-trials being conducted by colleagues at the Naval Research Laboratory.

Principal Investigators: Faculty from the Electrical and Computer Engineering Department, Aerospace and Ocean Engineering Department, and the Mechanical Engineering Department
Sponsor: Virginia Tech, Huntington Ingalls Industries, Marine Sonic Technology: a brand of Atlas North America, and Ping DSP

Description: The Shell Ocean Discovery XPRIZE challenges teams to develop technology for mapping the deep ocean faster and with more autonomy than is possible with today’s systems.  In the final round of the competition, participants are asked to survey 500 sq. km in 24 hours images of a specified object, and to find and image additional archaeological, biological or geological features. The Virginia Distributed Environmental Exploration Project X (DEEP-X) is an innovative system for rapid surveys and opportunistic discovery in the deep ocean.  The DEEP-X system is composed of a team of inexpensive autonomous underwater vehicles (AUVs) that intelligently and collaboratively explore the deep ocean.

August 2018 Update:  The Virginia Tech XPRIZE team successfully passed through the first phase of the contest and earned a spot in the finals.  In addition, the team split the $1M Millennium prize with the other eight teams that earned a spot in the finals. 

Regrettably, the team passed through the last go/no-go decision date without sufficient financial sponsorship for the XPRIZE team, and we have reluctantly withdrawn from the contest.  However, the marine autonomy and robotics program had a remarkably good year.  We have been awarded $4.5M in new projects in addition to our portfolio of on-going research projects. Among our new projects is an award to fabricate a team of our 690 AUVs, and other awards to develop and implement new approaches to multi-vehicle collaborative autonomy.  In other words, we will continue most of the research initiatives needed for XPRIZE (e.g., collaborative autonomy, subsea navigation, etc), but with emphasis on developing fundamental and practical contributions to marine autonomy and robotics for our research sponsors

Principal Investigators: Stilwell, Woolsey, Farhood, Patterson
Sponsor: Office of Naval Research (ONR)

We seek to develop a planning and control framework that will enable a human operator, who is possibly onboard a host asset (e.g., a submarine), to task one or more UUVs by providing high-level mission objectives. The framework will ensure probabilistic guarantees of mission success and safety of all manned and unmanned systems. For the case that the UUVs are engaged in a set of tasks before the arrival of the human operator, the planning and control framework will prioritize the human operator’s mission objectives. The planning and control framework will enable the UUVs to continue prior tasks, but only to the extent that they do not reduce the probability of the human operator’s tasking being successfully completed.