The Research Of New WIM Technology Based On Fiber Bragg Grating

The reasonable load of vehicle to the bridge load-bearing security, the path transportation security as well as the road maintenance and so on, is very important. With the continuous growth of mileages of highway in our country, the highway transportation in the logistics and the passenger transportation are becoming increasing significant. Some transport groups and individuals regardless of the vehicle's carrying capacity, the phenomenon that illegal overload transport frequently be reported in various newspapers. Some foreign scholars' research demonstrated that, the vehicle's axle load and the extent of pavement's damage have a certain proportion relations, overload is an important reason of which accelerated the pavement's damage. Under this background, the detection of vehicle load is particularly important; in addition, the change of method about toll collection also promoted the development of WIM (Weigh in Motion) .In WIM field, the traditional detection method is carries on under the static state, which means high accuracy, low efficiency, is not suitable to the site detection. Therefore, many countries in the world have spent most time on the study that how to weigh a running vehicle's load accurate, this technology is called WIM.At the present time, look around the domestic and foreign WIM product, we can find that the majority was developed based on the traditional electrical sensor. These sensors have a long history, and are mature in technology. However, they will inevitably face some problems, for example they are difficult to overcome the electromagnetic interference, corrosion and so on. These factors seriously influence the weighing results, so developing a new type of WIM system has become a major issue.Based on the research status of load cell and the needs of domestic market, in this paper, we use the advanced FBG (Fiber Bragg Grating) as the sensitive element, and do a series of theoretical and experimental research.This paper, conducted a detailed analysis about WIM technology, the relevant mathematical model, the principle of Fiber Bragg Grating, the structural design and signal processing algorithm (RLS) .In addition, the outdoor experiment also be carried on, and the acquired data was analyzed.Some work done in this paper is listed as follow:1) Establishes the mathematical model of dynamic WIM system;2) Analyze the signal processing algorithm, and do Matlab simulation; 3) The design of WIM platform;4) Adhere the FBG sensitive element to the load cell;5) The static calibration of the FBG sensor;6) Do the site experiment, acquire the weight signal of a bus, and make a detailed analysis.Comparing with the current WIM sensor, this new type sensor shows many distinctive characteristics, such as anti-interference, the high measurement precision. Experimental results showed that the WIM system based FBG sensor is feasible, and will have the broad application prospect.