GPS World, June 2016
DEFENSEUPDATE Figure 1 Sensor suite aboard TerraMax UGV independent benefits in the form of advanced driver assistance system ADAS features to benefit manual driving reducing accidents and collisions To facilitate detecting errors absent in an in vehicle drivers intuition the drive by wire system communicates with core vehicle diagnostic sensors It also utilizes add on sensors that enable monitoring of vehicle and auxiliary subsystem attributes such as hydraulic and pneumatic pressures ambient and local temperatures fuel and fluid levels battery charges and power usage All of this data is accessible from the control interface In addition threshold values are configured for each monitored sensor such that an operator will be advised if any components exceed warning or critical levels This ensures that severe conditions do not go unnoticed by an operator who could be at a distance beyond direct line of sight and may be preoccupied or otherwise unable to dedicate full attention to monitoring multiple UGVs downrange Perception Sensors The TerraMax UGV sensor suite FIGURE 1 uses multiple sensor modalities to provide robust sensing capability The primary sensor for analyzing terrain and obstacles is the high definition HD laser detection and ranging LADAR with 64 scanning lasers sweeping 360 degrees In addition radars are positioned around the vehicle to detect moving obstacles such as other vehicles Wideangle 54 GPS WORLD WWW GPSWORLD COM JUNE 2016 cameras are also positioned around the periphery to give a remote operator the ability to visually check vehicle surroundings A navigation solution using GPS and an inertial navigation system INS supports the ability to drive accurately even with limited GPS signal availability On the roof facing forward are two cameras used for teleoperation of the vehicle a wide dynamic range WDR camera for daytime use and a short wavelength infrared SWIR camera for night operations Perception Software The TerraMax UGV perception software leverages a multi sensor suite that compensates for the weaknesses of one sensing modality with the strengths of another for example relying upon the dustpenetrating ability of automotive radar when LADAR and visible spectrum camera feeds are obscured The perception software uses several modules to interpret the world around it terrain detection which assesses roughness of the nearby terrain and informs the selection of appropriate speeds terrain classification which distinguishes among foliage dust or other airborne obscurants and obstacles FIGURE 2 and enables traversability appraisals of the surrounding area and dynamic obstacle detection which tracks vehicles and dismounts and allows the UGV to exhibit defensive driving behaviors This software also affords situational awareness and a means for remote supervision of the vehicle by providing processed output for display at the operator control unit In addition fused sensor data are combined using novel registration techniques that couple the vehicles perception of its surroundings with ground truth geospatial mapping data to correct for errors in GPS position estimates This allows the system to be enhanced by rather than dependent upon GPS and vehicle to vehicle data Government testing has demonstrated the ability of the TerraMax UGV system to endure complete GPS blackout for more than 19 kilometers with no noticeable impact on mission performance Key features of the perception system are operable in all environments under all weather and lighting conditions installed inconspicuously on the base vehicle and capable of covert modes of operation able to deliver reliable system performance under extreme GPS degradation or denial Motion Planning Software This onboard software takes in an operators objectives regarding routing speed and intervehicle spacing as entered during mission planning or onthe fly It consequently observes processed sensor data from the perception system and calculates and executes speed and steering commands that guide the vehicle along an optimal path The motion planning software has been developed with machine learning techniques to emulate smooth human figure 2 Perception system display in the TerraMax UGV
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