In every country, road networks are one of the largest and highly expensive investment. Equally expensive are the consequences of not ensuring adequate road safety. This creates the need for an efficient and automatic system for the detection of overloaded vehicles [17]. One of the tools designed to measure the weight and individual axle loads of vehicles are the systems weighing vehicles in motion (WIM). Due to their measurement imprecision, WIM systems composed of two lines of sensors are only used as pre-selection systems. At present, the only viable option for reducing measurement uncertainty in dynamic weighing is to increase number of load sensors (Multi-Sensor systems; MS-WIM). The paper presents the results of research on a MS-WIM system equipped with 16 lines of load sensors. The conceptual objectives, system design, results of experimental evaluation of the system's accuracy, and the final conclusions based on a 6-year operating period, during which the system has been used under normal traffic conditions have been presented.

Due to their lack of driving controllability, overweight vehicles are a big threat to road safety. The proposed method for a moving passenger car load estimation is capable of detecting an overweight vehicle, and thus it finds its application in road safety improvement. The weight of a car’s load entering or leaving a considered zone, e.g., industrial facility, a state, etc., is also of concern in many applications, e.g., surveillance. Dedicated vehicle weight-in-motion measurement systems generally use expensive load sensors that also require deep intervention in the road while being installed and also are calibrated only for heavy trucks. In this paper, a vehicle magnetic profile (VMP) is used for defining a load parameter proportional to the passenger vehicle load. The usefulness of the proposed load parameter is experimentally demonstrated in field tests. The sensitivity of the VMP to the load change results from the fact that the higher load decreases the vehicle clearance value which in turn increases the VMP. It is also shown that a slim inductive-loop sensors allows the building of a load estimation system, with a maximum error around 30 kg, which allows approximate determination of the number of passengers in the car. The presented proof of concept extends the functionality of inductive loops, already installed in the road, for acquiring other traffic parameters, e.g., moving vehicle axle-to-axle distance measurement, to road safety and surveillance related applications.

Road Traffic Parameters Measuring System with Variable Structure: Systems of road traffic parameters measurement play a key role in the process of road traffic control, its supervision as well as in gathering and processing information for statistical purposes. Expectations of users of such systems mainly concern automation and provision of measurement continuity, possibility of selection of the measured road traffic parameters and high accuracy along with reliability of obtained results. In order to meet the requirements set for such systems, at the Department of Instrumentation and Measurement of the AGH University of Science and Technology in Cracow a new prototype system of road traffic parameters measurement - Traffic-1 - has been constructed. The innovativeness of the solution is manifested in the structure of the system that can be modified by the user adequately to current measurement needs and in the used algorithms of signals processing. The work contains a brief description of the constructed system with particular focus on the used innovations that are the result of many years of research work of the designers.

This paper describes temperature influence on the uncertainty of weighing results in Weigh in Motion systems (WIM). The analysis bases on the long-term investigation of the WIM site, as well as on simulation tests conducted on sensor and conditioning circuit models. The drawn conclusions suggest, that this uncertainty may be significantly reduced if a proper temperature correction algorithm is applied.