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See detailTowards optimal positioning of surveillance UGVs
Nilsson, U.; Ögren, P.; Thunberg, Johan UL

in Optimization and Cooperative Control Strategies (2009)

Unmanned Ground Vehicles (UGVs) equipped with surveillance cameras present a flexible complement to the numerous stationary sensors being used in security applications today. However, to take full ... [more ▼]

Unmanned Ground Vehicles (UGVs) equipped with surveillance cameras present a flexible complement to the numerous stationary sensors being used in security applications today. However, to take full advantage of the flexibility and speed offered by a group of UGV platforms, a fast way to compute desired camera locations to cover an area or a set of buildings, e.g., in response to an alarm, is needed. Building upon earlier results in terrain guarding and sensor placement we propose a way to find candidate guard positions that satisfy a large set of view angle and range constraints simulataneously. Since the original problem is NP-complete, we do not seek to find the true optimal set of guard positions. Instead, a near optimal subset of the candidate points is chosen using a scheme with a known approximation ratio of O(log(n)). A number of examples are presented to illustrate the approach. [less ▲]

Detailed reference viewed: 54 (1 UL)
Full Text
Peer Reviewed
See detailOptimal positioning of surveillance UGVs
Nilsson, U.; Ögren, P.; Thunberg, Johan UL

in Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (2008)

Unmanned ground vehicles (UGVs) equipped with surveillance cameras present a flexible complement to the numerous stationary sensors being used in security applications today. However, to take full ... [more ▼]

Unmanned ground vehicles (UGVs) equipped with surveillance cameras present a flexible complement to the numerous stationary sensors being used in security applications today. However, to take full advantage of the flexibility and speed offered by a group of UGV platforms, a fast way to compute desired camera locations that cover or surround a set of buildings e.g., in response to an alarm, is needed. In this paper we focus on two problems. The first is how to create a line-of-sight perimeter around a given set of buildings with a minimal number of UGVs. The second problem is how to find UGV positions such that a given set of walls are covered by the cameras while taking constraints in terms of zoom, range, resolution and field of view into account. For the first problem we propose a polynomial time algorithm and for the second problem we extend our previous work to include zoom cameras and furthermore provide a theoretical analysis of the approach itself. A number of examples are presented to illustrate the two algorithms. [less ▲]

Detailed reference viewed: 66 (0 UL)