US Army’s Autonomous Vehicle Focus Turns Towards Demo Bravo
IVsource.net
1 January 2000

Interest throughout the armed forces is growing steadily as the involved R&D organizations engage new user communities such as the Marine Corps, Military Police, and Engineering.  As in the highway community, incremental deployment of applications is seen as essential to progress.

Demo III Marches On

Meanwhile, the flagship Demo III program continues to advance the off- and on-road capabilities of their Experimental Unmanned Vehicles (XUVs).  They are now gearing up for their second major demonstration this fall -- Demo Bravo.
 

At a program review in December, vehicle designers looked back on the accomplishments of Demo Alpha, held last September at Aberdeen Proving Ground, Maryland.  Two XUVs successfully navigated unstructured terrain and intelligently maneuvered around most obstacles (negative obstacle detection was still developmental).  Road following and convoying was successfully accomplished during engineering testing but was not seen as mature enough for the prime demo.  The operating sensor suite consisted of machine vision (black & white, color, and infrared), stereo vision on a pan/tilt axis for gaze control, and millimeter wave radar (see the Fall 1999 IVsource article Stereo Vision Leads Demo Alpha Vehicles Cross-Country for more information.)

Since Demo Alpha, the engineering team has continued to integrate new sensors to improve autonomous mobility.  New functions up and running on the XUVs include laser ranging and vehicle following, and self-calibration for the stereo vision.  Major effort is going into improving negative obstacle detection, including repositioning the radar and laser higher up and further back on the vehicle to optimize the “gaze angle” for this function — designers say that the laser rangefinder provides an enhanced angular resolution beyond what the millimeter wave radar can deliver.

The system can now successfully detect a large negative obstacle, such as a roadside ditch, and detection of smaller obstacles is expected to follow quickly.  The R&D team has also kicked off development for the foliage-penetrating radar and is preparing to fully integrate the laser rangefinder into the sensor suite.  Key areas also being addressed include integration of gyroscopes into the laser system to assist in pointing, and reduction of the minimum range of the laser from 7 feet to 3 feet (from 215 cm to 90 cm) in order to assist the negative obstacle detection task.

The total autonomous mobility (AM) suite for Demo Bravo is planned to consist of: millimeter wave radar, stereo infrared and visible-spectrum cameras, meteorological (weather) sensors, accelerometers, laser rangefinder, and front/rear bumper sensors.  The bumper sensors provide force feedback if the vehicle strikes an obstacle, such as a small tree, enabling the system to make a decision to either roll over it or go around it.  AM software developments will include an enriched obstacle map, intelligent driving/velocity control (which can help control sensor jitter), and algorithms for gaze control and convoying.

Engineers and software developers are now working towards AM testing scheduled for late April at Aberdeen.  Two additional XUV’s -- bringing the total count to four -- will be completed by June 16 to assist in test and integration for Demo Bravo during July.  Initial dry runs at the new demo site (Ft. Knox, Kentucky) will start in August, in preparation for the demo during October 13-26.  The new XUV testing ground for Demo Bravo will provide significantly rougher terrain than last year’s demo had, and the vehicles will be tested extensively by soldiers under realistic conditions, in order to assess the XUVs’ usefulness in supporting the military scout function.

The Army Research Laboratory at Aberdeen manages the Demo III program, with General Dynamics Robotics Systems (GDRS) as the prime contractor.  Supporting contractors and technology providers include SAIC, Sarnoff Labs, NASA’s Jet Propulsion Laboratory, and the National Institute of Standards and Technology (NIST) of the US Department of Commerce.
 

[Top]
 

The Demo III XUV Autonomous Vehicle Platform, similar to those being slated for Demo Bravo

... contact Scott Myers, GDRS, at scott@rst.com.
 

[Top]