Power Export Upgrade for the Diesel Hybrid RST-V

23 May 2005

General Dynamics Land Systems has received a $5.9 million rider on its development contract to augment the currently specified features of the new hybrid diesel-electric Reconnaissance, Surveillance and Targeting Vehicle (RST-V). The upgrade reflects design changes requested for various US Marine Corps (USMC) applications, including a 30-kW export power capability to power battlefield loads such as radars.

The basic demonstration unit features a powertrain based on a front-mounted, turbocharged, intercooled 2.5-liter Detroit Diesel common rail direct injection diesel engine that develops 114 kW (152 hp). The diesel engine powers a 110-kW Magnet Motors permanent magnet generator that drives four 50-kW Magnet Motors permanent magnetic hub motors, mounted one in each of the four wheel hubs. The power generation system also includes twin SAFT Li-Ion battery packs with total rated output of 20 kW hours and a peak power output of 80 kW.

The hybrid electric drive system enables the vehicle to operate in stealth (battery-only), hybrid or engine-only (no use of the energy store) modes. The system can be adapted to use a full spectrum of energy storage options, from a base diesel electric with no energy store, to ultra capacitors, to any battery chemistry.

The in-hub electric drive, unfettered by differentials, CV joints or half shafts to bring torque to the wheels like conventional drivetrains, enables a unique folding, pneumatic suspension in the RST-V. The suspension can reduce the dimensions of the vehicle by pulling the wheels in from a 2-meter (79-inch) footprint to a 1.6-meter (62-inch) footprint, and dropping the height so the base is 0.1 meter (4 inches) off the ground. This enables the RST-V to scrunch down for transport, yet be able to offer a wide, stable stance when deployed.

The vehicle has a demonstrated maximum road speed of 112 km/h (70 mph). With 95 liters of fuel (25 US gallons), the Shadow has an unrefueled range of 758 km (471 miles) at a speed of 50 km/h (31 mph). Using only battery power the vehicle’s range is 32 km (20 miles).

General Dynamics Land Systems has partnered with the Defense Advanced Research Projects Agency (DARPA), the Office of Naval Research (ONR) and the USMC on the RST-V program since 1999. In this latest round of funding, DARPA contributed $5 million of the total $5.9 million.