TECHNOLOGY AREA(S): Ground/Sea Vehicles

ACQUISITION PROGRAM: Unmanned Swarming Amphibious Assault Craft

OBJECTIVE: Develop a physics-based simulation to allow autonomy developers to evaluate perception sensors, vehicle control, obstacle avoidance, and path planning algorithms to maneuver an amphibious vehicle in and through the surf zone.

DESCRIPTION: The Office of Naval Research is interested in accelerating autonomy capabilities for landing craft and amphibious vehicles with a focus on complementing experimentation with simulation.� A major challenge of these vehicles is operating from the sea through the surf zone. A realistic simulation environment is required which provides the appropriate sensor feedback and vehicles motions for software-in-the-loop testing.� Various simulators exist for simulating robot environments [Ref 1] as well as numerous gaming environments and physics engines.� Amphibious vehicle simulators have also been developed [Ref 2], but have not incorporated perception and autonomous controls.� This simulator will combine the realistic response of a vehicle in a surf zone environment with autonomous control to allow for testing, training, and evaluating autonomy algorithms for a range of vehicles such as the Landing Craft Utility (LCU), Amphibious Assault Vehicle (AAV), and smaller vehicles such as those being developed under ONR�s USAAC program.

To achieve this, the simulator must:
- represent the sea surface (to include breaking waves), bathymetry, and beach or landing zone characteristics
- characterize sensor performance in visual, thermal, and radar bands for detection of waves, obstacles, and land features
- describe underwater features such as bottom types and depth in the acoustic and visual spectrum
- incorporate a realistic vehicle response model for wave, surf, and bottom interactions
- allow for modular autonomy components such as sensors, fusion, path planning, obstacle avoidance, and low-level vehicle controls to be incorporated and executed by the vehicle under simulation
- incorporate static and moving obstacles (such as floating objects or small craft) on the surface and submerged

The simulation should allow the user to select a variety of geographic locations, environmental conditions (time of day, wind speed, sea state, etc.), and vehicle designs to evaluate autonomy software components.� To ensure that a large sample of potential interactions can be addressed, it is desirable for the simulation to run in faster than real time.� It is not expected that the performer will develop fast running numerical analysis for hydrodynamics or wave characterization data sets, but incorporate existing techniques and data sets into the simulation.� Reference 3 provides a link to the Unmanned Swarming Amphibious Assault Craft (USAAC) BAA which defines the desired operating environments and notional vehicle characteristics and performance that will need to be addressed in this simulator.

PHASE I: The performers will conduct an investigation of existing simulation environments and physics engines and design the base architecture.� The architecture will define the interfaces and interoperability between existing software components and any new components that must be developed as well as define how the modular autonomy aspects will be included.� The performer will explore fast-running hydrodynamic tools and wave models and determine how an accurate representation of wave-vehicle interactions will occur through the surf zone and transitioning to land.� The performer will also identify or develop wave feature rendering to be used for the sensor detection modalities.

During the option period, the performer will produce a proof-of-concept simulation that demonstrates a single vehicle moving through the environment with notional sensing, path planning, and control algorithms.

PHASE II: In Phase II, the performer will develop a prototype of the simulation with fully defined wave characterization, vehicles dynamics, and autonomy component integration to allow for simulation of a vehicle from open ocean through the surf zone and onto land.� The performer will be provided data sets of a variety of vehicles and environmental conditions to be used for validation.� The performer will implement the Government provided autonomy components in the simulation and compare the simulation results to collected experimental data.

PHASE III DUAL USE APPLICATIONS: In Phase III, the performer will use the simulator environment to evaluate autonomy approaches for perception, path planning, world modeling, and vehicle controls for programs such as the USAAC.� The performer will provide a common simulation environment to test and evaluate autonomy approaches in a range of environmental conditions and locations to identify limitations of their approach prior to live testing.� The application of this simulation may be valuable to environmental monitoring and surveys and the development of commercial and recreational craft.� The simulation may also be used in a gaming environment.

REFERENCES:

1. Robot Simulator - Gazebo Simulation; http://gazebosim.org/

2. Lachman, L.W. 2006. Surf zone modeling for an EFV Trainer for the USMC. Interservice/Industry Training, Simulation, and Education Conference. December 4-7, Florida.

3. Broad Agency Announcement: N00014-17-S-B004; Autonomy and Unmanned Vehicle Technologies to Support Amphibious Operations; Retrieved from https://www.onr.navy.mil/-/media/Files/Funding-Announcements/BAA/2017/N00014-17-S-B004.ashx

KEYWORDS: Autonomy; Amphibious; Landing Craft; Surf; Perception; Simulation