Rugged Mobile Robotic System for Surveillance and Reconnaissance

Sandia's Intelligent Systems and Robotics Center (ISRC) has developed Marvin, an extremely rugged mobile robotic system. This state-of-the-art achievement was built upon Sandia's established core capabilities in the areas of systems integration and designing and building rugged and reliable ground robotic platforms. In October 1998, Marvin not only successfully demonstrated these capabilities, but also took them to the next level: demonstrating the capability of a mobile robotic system to withstand violent deployment via drop from a moving truck, forceful ejection from a window, and other extreme scenarios.

Sandia had previously delivered rugged field-ready systems with SARGE, the Surveillance And Reconnaissance Ground Equipment robot. SARGE was the first mobile robotic vehicle to undergo extensive proof-of-concept testing with a US Army scout battalion at the Ft. Benning, Georgia, US Army Infantry School and with the US Marines in an "urban warrior" mock battle exercise in the San Francisco Bay Area.

Customized technology was used to enable Marvin to survive a wide range of high-impact deployments (at impact velocities exceeding 75 feet per second), tumble to a stop, and drive away completely intact and operational. The ISRC successfully met these criteria by designing

• wheels that mitigate the shock environment. These specially designed Kevlar-urethane composite wheels crush upon impact, absorb the shock forces, and spring back to their original shape. These wheels limit the deceleration forces on internal components and are the key to the system's survival and success.
• a symmetrical vehicle that can operate either side up. This unique design eliminates the need for complicated self-righting mechanisms.
• on-board sensors that determine the vehicle's resting orientation. This information is used to automatically correct driving commands so that the system will operate no matter which side is up.

Systems integration tasks resulted in additional features being included in Marvin's design. These features facilitate Marvin's use by special operations forces as a surveillance and reconnaissance robot in an urban environment. The rugged robot has

• a teleoperated system. A human is in direct (remote) control of the vehicle and its sensor payloads.
• a mobile platform. The spin-turn capability of the platform allows the operator to command the entire platform to turn so that mission-specific sensor packages can perform surveillance, such as a video camera recording the field of vision as it pans the area. The platform configuration can carry a variety of mission-specific sensor payloads.
  
• a single uncooled infrared video camera, or FLIR (Forward Looking Infrared). The FLIR, which is carried by the platform, provides imagery to the operator both for driving and surveillance during day or night reconnaissance missions.
• built-in global positioning system (GPS) guidance aids. The guidance system shows an overlay of a vehicle (robot) icon on a high-resolution aerial photograph or topographic map to allow the operator to determine vehicle location relative to the final destination and local area landmarks and to help the operator direct the vehicle to the desired destination.
  
• three redundant patch antennas on both the top and bottom surfaces of the vehicle. One antenna is for the video link, which transmits video and audio from the vehicle to the operator. The second is for the two-way data link, which receives commands from the operator and transmits status information back to the control station. The third is the GPS antenna used for position location. The antennas are protected by Kevlar radomes during the violent tumbling experienced on deployment. The radomes also provide a smooth exterior surface that will not hang up on obstructions when the robot traverses rough cross-country terrain.

This combination of state-of-the-art technologies in one robot will allow the ISRC to rethink the way that mobile reconnaissance platforms are deployed. Because the plans for Marvin include deployment from a moving vehicle, aircraft, or ballistic launch into extremely rugged terrain, the robot will be able to perform surveillance in areas that typically have been very difficult or impossible for humans to reach. In addition, by assuming this job, Marvin can determine the safety of an area before people are sent in, thus creating a buffer between human soldiers and a dangerous surveillance destination.

The development of Marvin has contributed significantly to Sandia's core capabilities of designing and building extremely rugged and reliable ground robotic platforms, and the knowledge and experience gained will be extremely valuable to both Sandia and its customers when developing the next generation of mobile reconnaissance platforms.