Page 24 - Autonomous Mobile Robots
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8                                      Autonomous Mobile Robots


                                TABLE 1.1
                                Classes of UGV
                                Class        kph     Capability gaps    Perception tasks  TRL6
                                Searcher (TGV)    All-weather sensors  Not applicable      2006
                                Donkey (SAP/F)  40  Localization and mapping  Detect static obstacles,  2009
                                                   algorithms        traversable paths
                                Wingman      100  Long-range sensors and  Terrain assessment to detect  2015
                                 (PC-AGV)          sensors for classifying  potential cover
                                                   vegetation
                                Hunter-killer  120  Multiple sensors and  Identification of enemy  2025
                                 (NC-AGV)          fusion            forces, situation awareness



                                The road map identifies perception as the priority area for development and
                                defines increasing levels of “technology readiness.” Some of the require-
                                ments and capability gaps for the four classes are summarized and presen-
                                ted in Table 1.1. Technology readiness level 6 (TRL 6) is defined as the
                                point when a technology component has been demonstrated in a relevant
                                environment.
                                   These roles range from the rather dumb donkey-type device used to carry
                                equipment to autonomous lethal systems making tactical decisions in open
                                country. It must be remembered, as exemplified in the inaugural Grand
                                Challenge, that the technology readiness levels of most research is a long
                                way from meeting the most simple of these requirements. The Challenge is
                                equivalent to a simple A-to-B mobility task for the SAP/F class of UGVs. On
                                a more positive note, the complexity of the Grand Challenge should not be
                                understated, and many past research programs, such as Demo III, have demon-
                                strated impressive capability. Such challenges, with clearly defined objectives,
                                are essential for making progress as they bring critical problems to the fore and
                                provide a common benchmark for evaluating technology.



                                1.2 VISUAL SENSING TECHNOLOGY
                                1.2.1 Visual Sensors
                                We first distinguish between passive and active sensor systems: A passive sensor
                                system relies upon ambient radiation, whereas an active sensor system illumin-
                                ates the scene with radiation (often laser beams) and determines how this is
                                reflected by the surroundings. Active sensors offer a clear advantage in outdoor
                                applications; they are less sensitive to changes in ambient conditions. How-
                                ever, some applications preclude their use; they can be detected by the enemy




                                 © 2006 by Taylor & Francis Group, LLC



                                  FRANKL: “dk6033_c001” — 2006/3/31 — 16:42 — page8—#8
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