Rapid check method for truck loaded with fresh agricultural products on expressway

To improve the traffic efficiency of trucks loaded with fresh agricultural products (FAPs) and reduce the workload of inspectors at toll stations, a rapid check model for trucks loaded with FAPs based on a laser ranging system was proposed. The characteristics of main types of trucks loaded with FAPs was analysed, and common types of trucks loaded with FAPs were determined by traveling route induction. The laser ranging system of carriage outline was introduced and the cargo density database was established as the basis of judgment. According to the required loading limits of tolling for free, and considering the probability distribution of cargo densities, the upper and lower thresholds of the cargo density were determined, and a cargo density judging model for unreasonable loading was developed for the case of an 8×4 truck. Based on the features of space between truck axles, the moment balance principal (MBP) was used to deduce the theoretical weight of the assembled axles, which were close to the front of the carriage. The assembled axles judging model was then developed based on the MBP. The feasibilities of the cargo density judging model and assembled-axles judging model were verified by the measuring data of toll stations, the computational errors of the two models were analyzed, and the advantages of the rapid check model were compared with those of the manual model. Analysis results show that there are five main types of trucks in FAP transport, The deviation rates of volume and density measured by the cargo density judging model are ±3.75% and ±4.94%, respectively, which is considerably less than 50% of the tolerance of a reasonable range or warning range in the judging logic. The dependence of the cargo density judging model based on the laser ranging system is less than that of the assembled axles judging model. The efficiency of the rapid check model based on the two models is 5.97 times higher than that of the manual inspection, which can effectively improve the efficiency of the lane. The inspection rate of all the investigated trucks is 16.62%, which can reduce the inspection frequency and economize labor and employment. Although the average time of the added selection and input parameter process is 0.41 min, it is only 15.70% of the time of the manual inspection. 4 tabs, 3 figs, 30 refs.