No abstract

Tactical mobile robots used in military and lawenforcement operations normally require a robust, longrange, and non-line-of-sight (NLOS) communications link to the remote control station. This is especially true for Explosive Ordnance Disposal (EOD) operators using robots to defeat Improvised Explosive Devices (IEDs). Highfrequency digital radio communications, currently the preferred technology, are subject to line-of-sight (LOS) limitations, and thus are often impossible to maintain in urban environments. We have developed a system that will allow the mobile robot to carry multiple relay radios that are automatically deployed when and where needed in order to maintain robust communications. This process is completely transparent to the operator and is entirely handled by the ad-hoc network formed by the relay radios. The system is plug-and-playable, and can be attached to many manned and unmanned vehicles requiring long-range and non-LOS operational capability. Experimental data compares the effective range achieved with and without the use of our relay deployment system.

Mobile robot tipover is a concern as it can create dangerous situations for operators and bystanders, cause collateral damage to the surrounding environment, and result in an aborted mission. Algorithms have been developed by others to assess the stability of the robot, and many of these algorithms have been demonstrated using simulated data. In order to verify that these algorithms accurately match real-world behavior, we have collected data of a mobile robot tipping over and then compared this data to the stability measures provided by three algorithms: Zero-Moment Point (ZMP), Force-Angle stability measure (FA), and Moment-Height Stability measure (MHS). A small mobile robot platform based on the iRobot PackBot drove a course including ramps and obstacles; an IMU and GPS provided inertial and positional data for the algorithms, and the actual tipover event is determined from video footage of the tests. The average normalized measure at tipover event initiation was found to be 0.665 for ZMP, -0.094 for FA, and 0.023 for MHS, where a value of 1 corresponds to resting stability. Standard deviations were 0.38, 0.84, and 0.67, respectively. The measures show a significant amount of noise, which is likely due to the vibrations caused by movement of the tracks and could be reduced by employing additional filtering during data collection. The preliminary real-world data validates these tipover algorithms as able to assess robot stability, and they can be used as part of a tipover avoidance system.

In March of last year, engineers from SPAWAR Systems Center, San Diego (SSC San Diego) and Allied Aerospace (formerly Micro Craft, Inc.) conducted the first known launch of a Vertical Takeoff and Landing Unmanned Air Vehicle (UAV) from an Unmanned Ground Vehicle (UGV) in Holtville, California (2002). The launch concluded a week-long demonstration to the Defense Advanced Research Projects Agency as part of the U.S. Army's Future Combat Systems Organic Air Vehicle Phase I effort. The launch involved Allied Aerospace's 29-inch Lift Augmented Ducted Fan iSTAR UAV and SSC San Diego's Mobile Detection Assessment Response System-Exterior UGV.SSC San Diego is now pursuing integration efforts in order to increase base security and defense missions by decreasing time and personnel required to maintain a UAV during operations. The main project goal is to develop a system that allows a UAV to be launched, recovered, and refueled in order to provide force extension through autonomous aerial response. This paper presents an overview of near term mission areas, benefits, and target recipients of the integrated system. It also provides a description of the project plan, including challenges faced and lessons learned, in order to inspire further integration ideas and efforts with existing unmanned systems. Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. Report Documentation Page

In the area of logistics, there currently is a capability gap between the one-ton Army robotic Multifunction Utility/Logistics and Equipment (MULE) vehicle and a soldier's backpack. The Unmanned Systems Branch at Space and Naval Warfare Systems Center (SPAWAR Systems Center, or SSC), San Diego, with the assistance of a group of interns from nearby High Tech High School, has demonstrated enabling technologies for a solution that fills this gap. A small robotic transport system has been developed based on the Segway Robotic Mobility Platform TM (RMP). We have demonstrated teleoperated control of this robotic transport system, and conducted two demonstrations of autonomous behaviors. Both demonstrations involved a robotic transporter following a human leader. In the first demonstration, the transporter used a vision system running a continuously adaptive mean-shift filter to track and follow a human. In the second demonstration, the separation between leader and follower was significantly increased using Global Positioning System (GPS) information. The track of the human leader, with a GPS unit in his backpack, was sent wirelessly to the transporter, also equipped with a GPS unit. The robotic transporter traced the path of the human leader by following these GPS breadcrumbs. We have additionally demonstrated a robotic medical patient transport capability by using the Segway RMP to power a mock-up of the Life Support for Trauma and Transport (LSTAT) patient care platform, on a standard NATO litter carrier. This paper describes the development of our demonstration robotic transport system and the various experiments conducted.