1) simple structure
2) convenient construction
3) flexible debug, high security.
4)low maintenance costs

Parking guidance system is very important for ITS(intelligent transportation system),Europe and USA have conducted massive researching work it which can greatly ease the urban traffic congestion, reduce road occupation and significantly enhance the utilization of existing parking facilities, achieve good social and economic benefit. It designed not only for the large single parking lots but also for the multiple parking lots. Its good originality and high performance can let the drivers know the real-time information of free parking stall of relative parking lots and induce the vehicles go into the berth directly .It avoid driving blindness and improve the utilization rate of the city road and parking lot.

It can offer comprehensive parking guidance service and greatly improve the service standard improve the utilization of park berth, set up the perfect image by using the parking guidance system. The parking guidance which designed and produced by ourselves has the following characteristics:

For users  simple structure, convenient construction, flexible debug, high security.For managers  easy to maintenance and operate, higher automation and offer high quality, security , shortcut service and establish a new image.For investor low maintenance costs, significantly advertising effectiveness, more profits1.      program design

The parking guidance system is usually composed by the follow three parts : data collection system, data issuing system, and data management analyzing system.The main function of the data collection system is making a real-time collection for the parking information in the parking lots and influx the data to the data processing centre. The main function of data issuing system is sending the information about every free parking stall of the location data processing centre to LED display installed in every entrance and entry of parking lots and traffic main artery by the two ways of wire and wireless. The main function of the data analyzing manage system is stating, analyzing, printing report for the received real-time data from the location data procession centre.

In the present technical condition, there are two collection ways.

1) the vehicles` flux collection by the detect loop at the entrance & exit.

2)The vehicles` collection by the ultrasonic detector.

Both of them have merits and demerits respectively

The first collection way is using the accumulative calculation method,installing two detect loop at the entrance & exit of every parking lot to detect the vehicles` length and run direction for vehicles` accumulation or decreased statistics. It has the low cost, construction simple, but a certain accumulation error is existing (usually one in a thousands).the statistics data must be calibrated within a period.

The second collection way using the “calling step by step” method, Installing a ultrasonic detector in every  empty space to detect weather car is being or not, stating the information of the parking space through the collection terminal `inquiring to every ultrasonic detector. The advantage of this way with low error, however, high cost together with complex construction.

No matter in the vehicles flux `collection condition or in the car space collection condition, all the collected information should be transported to the location data procession centre through the data collection terminal and CAN bus, and then the processed data should be transported to the display around in the near empty car space by the way of CAN bus or wireless to direct the driver to choose the right driving way. CAN Bus LAN control system of parking lots is composed of TTA-108 AND TTC-101.Empty location display module is composed of LED displays with stainless steel frame and light boxes with the LED the digital pipe embedded. Install one TTC-108 at each entrance or exit of single-driveway. N entrance and exit of the driveway need to install N TTA-101. A distributed control system called “N+1 is formed by the star connection of CAN bus and the location data procession centre at the vehicles collection terminal condition.

One set ultrasonic detector should be installed on each park space and each collection terminal can connect 32 ultrasonic detectors, the amount of the collection terminal is determined by the number of park space of in the parking stall which can formed a distributed control system through the star connection of the CAN bus and location data procession centre in the park space collection condition.

The parameters of code, way of data collection should be set and the following operation should be conducted after finishing the equipment installation

1)Set up the total number of the car parking distribution area and TTC-101(total number of entrance & exit)

2) Set up the total number of the parking spaces in each area and the existing vehicles` number.

3)set up the communication address of the LED display for displaying the empty car spaces in each distributed area.

4)The entrance and exit direction of each collection terminal and the code of the relative area.

When vehicles is on the detect loop of the collection terminal, the running direction is detected and take count of the vehicles number and send those information to the location data procession centre by the CAN bus synchronously ,the car space information which counted in according with the formal setting information by TTA-108 in each distributed area  and which is send to each TTC-101 with the broadcast way by the CAN bus,After receiving the broadcasting information and sent the car space information send to the LED display by the way of wire or wireless,each LED has an address and which is only corresponding to the code of each car location and display the rest corresponding car location information.