A method for generating a calibration function of a WIM sensor that is arranged in a roadway and measures a wheel force exerted on the surface of the roadway includes recording the roadway's road profile. A wheel force is determined by a simulation. The simulation is used to determine the dependency of the wheel force on the road profile for at least one position of the road profile that has been recorded in the first step. The dependency is used to minimize the influence of the road profile on the measured wheel force of the WIM sensor.

Weigh-in-motion sensors comprise a beam including a plate with a load-bearing surface, and a tube portion including a base wall and a cover and defining a cavity therebetween. A sensing package is disposed within the cavity and is under pre-load with the cover and the base wall. The sensing package comprises a piezoelectric element. The base wall includes an aperture extending from a mounting surface to the cavity. The aperture includes a fastener therein to secure the sensing package within the cavity. The fastener is sized having a cross-section dimension taken through a center axis of the fastener that is greater than that of a cross-section dimension of the piezoelectric element taken along the fastener center axis. In an example, the fastener has a cross-section dimension sized about 10 percent or greater in dimension than that of the respective cross-section dimension of the piezoelectric element.

A displacement and weight association apparatus includes a measuring unit configured to measure a displacement amount generated on a structure by a weight of a vehicle traveling on the structure; an aggregating unit configured to obtain a distribution of the measured displacement amount; an extracting unit configured to extract a displacement amount corresponding to a car from the distribution; and an associating unit configured to associate the extracted displacement amount with a weight of the car.

A measurement method includes: a step of acquiring, based on observation information obtained by an observation device, first observation point information including a time point when each of a plurality of parts of a moving object passes a first observation point of a structure and a physical quantity which is a response to an action of each of the plurality of parts on the first observation point; a step of acquiring, based on the observation information, second observation point information including a time point when each of the plurality of parts passes a second observation point and a physical quantity which is a response to an action of each of the plurality of parts on the second observation point; a step of calculating, based on the first observation point information, the second observation point information, a predetermined coefficient, and an approximate expression of deflection of the structure, a deflection waveform of the structure generated by each of the plurality of parts; and a step of calculating a deflection waveform of the structure generated by the moving object by adding the deflection waveform of the structure generated by each of the plurality of parts.

A measurement method includes: a step of acquiring first observation point information including a time point when each part of a moving object passes a first observation point and a physical quantity which is a response to an action; a step of acquiring second observation point information including a time point when the each part passes a second observation point and a physical quantity which is a response to an action; a step of calculating a deflection waveform of a structure generated by the each part; a step of adding the deflection waveforms to calculate a moving object deflection waveform, and calculating a path deflection waveform based on the moving object deflection waveform; a step of calculating a displacement waveform by twice integrating an acceleration of a third observation point; and a step of calculating, based on the path deflection waveform, a value of each coefficient of a polynomial approximating an integration error, and correcting the displacement waveform based on the value of each coefficient.

A method to calibrate a Weigh in Motion (WIM) sensor that is arranged in a road flush with a road surface for determining a force exerted on the road surface by a vehicle's wheel transgressing the WIM sensor uses an evaluation unit that calculates the wheel force upon receiving the vehicle's velocity and a distance signal from a first device fixed on the vehicle and coordinates the wheel force with a synchronized signal from the WIM sensor to generate a calibrate function for the WIM sensor. The evaluation unit continuously adjusts the wheel force to take into account one or more of wheel pressure, wheel temperature, wheel tilt and vehicle acceleration. A system employing the method includes the vehicle, the evaluation unit, the first device, a synchronization device such as a GPS unit, and sensors for one or more of pressure, temperature, tilt and acceleration.

A measurement method include a step to obtain observation point information, including physical quantities in association of a plurality of times, via observation devices at observation points of a structure on which a moving object moves, a step to calculate a correction coefficient that corrects the physical quantities based on a plurality of time periods and a reference time periods, a step to calculate a plurality of deflection waveforms of the structure generated by a plurality of parts of the moving object, a step to calculate a second deflection waveform of the structure generated by the moving object by adding the plurality of deflection waveforms, and a step to calculate a displacement of the structure based on the second deflection waveform. The structure is a superstructure of a road bridge or a railway bridge.

A hollow profile for a WIM sensor elongates along a longitudinal direction and includes a plate-shaped force introduction element, an anchoring element and a tubular element disposed between the force introduction element and the anchoring element. The tubular element is integrally connected to the force introduction element and to the anchoring element and encloses a first cavity. The anchoring element encloses at least one second cavity. The anchoring element, tubular element and force introduction element are formed integrally with each other.

A transducer assembly for mounting in a roadway includes a hollow profile defining sides extending along a longitudinal axis, an insulating element arranged on the exterior of the sides of the hollow profile. The profile defines an interior facing away from the exterior of the sides and defining a cavity. A force sensor assembly is disposed within the cavity of the hollow profile. The insulating element is secured to the hollow profile by a positive fit connection and is configured to insulate the transducer assembly from a rolling force acting on the sides of the hollow profile. When the transducer assembly is installed in a roadway, the force sensor assembly is configured to detect a weight force exerted onto the hollow profile.

Provided is a charging system including: an axle load meter disposed on a lane and configured to measure an axle load of each of a plurality of axles of a vehicle traveling on the axle load meter; an acceleration information acquisition unit configured to acquire, from the vehicle, vertical-direction acceleration information associated with each of the axles; a correction calculation unit configured to calculate a corrected axle load for each of the axles by correcting, based on the vertical-direction acceleration information, a measurement result for each of the axles obtained by the axle load meter; and a toll determination unit configured to determine a toll for the vehicle based on the corrected axle load for each of the axles.