Mark Christmann

Multisensor Based Indoor Vehicle Localization System for Production and Logistic

In this paper a multisensor based indoor vehicle localization system for production and logistics is introduced. To track the position and the orientation of a moving vehicle a set of distance values to several points on the vehicle is measured by a wireless ranging system. The beacons of the wireless system are mounted at known positions in the surrounding infrastructure. It is shown that conventional multilateralization is not very practical to solve the required positioning task. In order to match the complete geometry of the forklift to a set of measured distance data, a heuristic nonlinear optimization method is applied. With our novel approach it is possible to solve the complex underlying transformation problem and to calculate the position and angle of the forklift for nearly arbitrary measuring conditions. The achieved accuracy is optimal in the least squares sense. For situations where the wireless access to the vehicle is disturbed, the localization system is assisted by data from a laser scanner. By matching subsequent scans relative movements of the vehicle are be determined precisely. The fusion of an optical relative sensors and a wireless absolute localization system allows for a flexible and steady control of transportation processes even in complex and dynamically changing environments

An overview of wireless local positioning system configurations

Over the last years tremendous improvements of wireless positioning systems have been achieved. System accuracy has improved drastically and maturity changed from hand-soldered lab demonstrators to commercial products. In parallel applications moved from small, experimental installations to coverage of complete sites. Consequently the research focus shifts away from the positioning core technology to system aspects. Critical issues now are simultaneous handling of a large amount of mobile units like tags or vehicles with acceptable update rate, coverage of large areas requiring multiple cells and cell-handover, quick exchange of positioning data and fusion with other local information. This paper reviews the most common approaches to wireless positioning from the system perspective. Requirements on the infrastructure are pointed out, the communication effort is analyzed, energy consumption of the mobile unit is evaluated and feasibility of sensor fusion with other available information is investigated.

Remote local positioning radar

Based on the FMCW radar principle a mobile measuring unit simultaneously measures the distance to all modulated active reflector units that are within the range of the base station. This work elaborates on a specific implementation of such a remote positioning system, whose transponder units (tags) are simply attached to various measured objects. The main advantages are the low costs of the mobile units, the high update rate, which is possible in this kind of system, and low power consumption. In contrast to the conventional self-positioning LPR-system it is now possible to measure many mobile tags at the same time in real-time and to build up cell structures in widely ramified buildings.

Steady Delivery: Wireless Local Positioning Systems for Tracking and Autonomous Navigation of Transport Vehicles and Mobile Robots

For many players in the service and manufacturing sectors, the cost associated with transportation processes is a key factor in competitiveness and market success. Innovations such as wireless connectivity, RF identification (RFID), and the Internet of Things have already transformed these industries, and this trend-stimulated by modern wireless technologies, wave-based imaging systems, and autonomous driving-is set to continue.