阅读说明：本技术 一种新型车轮测速装置 (Novel vehicle wheel speed measuring device ) 是由 魏亚然 苏莘 谭渝 于 2020-05-15 设计创作，主要内容包括：本发明属于自动测量技术领域,特别涉及一种基于AVR单片机的车轮测速装置。本发明包括电源模块、AVR单片机、开关型霍尔传感器、超量程报警模块、上位机通信模块。AVR单片机作为整个测量系统的数据处理和控制核心,开关型霍尔传感器的输出为单个脉冲,直接接至AVR单片机,利用AVR单片机的输入捕捉功能计算两个相邻脉冲之间的时间差,并结合车轮的直径,经过简单的运算便可计算出轮子的角速度和线速度,计算结果可上传至LABVIEW上位机终端显示,同时上位机也可向AVR单片机发控制指令,当所测结果超阈值时则驱动声光报警,本发明可方便测量车轮速度,适合各种直径的车轮。(The invention belongs to the technical field of automatic measurement, and particularly relates to a wheel speed measuring device based on an AVR single chip microcomputer. The invention comprises a power supply module, an AVR singlechip, a switch type Hall sensor, an over-range alarm module and an upper computer communication module. The AVR singlechip is used as a data processing and control core of the whole measuring system, the output of the switch type Hall sensor is a single pulse and is directly connected to the AVR singlechip, the time difference between two adjacent pulses is calculated by utilizing the input capture function of the AVR singlechip, the diameter of the wheel is combined, the angular speed and the linear speed of the wheel can be calculated through simple operation, the calculation result can be uploaded to a LABVIEW upper computer terminal for display, meanwhile, the upper computer can also send a control instruction to the AVR singlechip, and when the measured result exceeds a threshold value, an acousto-optic alarm is driven.)

1. The utility model provides a wheel speed sensor based on AVR singlechip which characterized in that: the device comprises a power supply module, an AVR singlechip, a switch type Hall sensor, an over-range alarm module and an upper computer communication module; the connection relationship of each part is as follows: the power supply module provides working power supply for the AVR single chip microcomputer, the switch type Hall sensor and the over-range alarm module; the output of the switch type Hall sensor is directly connected to an input unit of the AVR singlechip; the AVR singlechip is connected with the over-range alarm module through a specific I/O interface; the serial port of the AVR singlechip is connected with an upper computer; all modules work cooperatively to finish the wheel speed measurement work together.

2. The vehicle wheel speed measuring device based on the AVR stand-alone as claimed in claim 1, wherein: the output voltage of the power supply module is 5V/DC.

3. The vehicle wheel speed measuring device based on the AVR single chip microcomputer as claimed in claim 1, wherein: the model of the switch type Hall sensor is AH 04E.

4. The vehicle wheel speed measuring device based on the AVR single chip microcomputer as claimed in claim 1, wherein: the AVR singlechip is ATmegal 28.

5. The vehicle wheel speed measuring device based on the AVR single chip microcomputer as claimed in claim 1, wherein: the over-range alarm module is composed of a buzzer and an alarm lamp.

Technical Field

The invention belongs to the technical field of automatic measurement, and particularly relates to a wheel speed measuring device based on an AVR single chip microcomputer.

Background

In daily life and some production processes, it is generally required to obtain the angular velocity or linear velocity of a rotating body such as a wheel, and the characteristics of the switching type hall sensor are well suited for the measurement of these physical quantities. Therefore, in order to conveniently and economically measure the angular velocity or linear velocity of the wheel, the AVR singlechip is used as a control core, and a simple and quick wheel speed measuring device is designed by combining the Hall sensor. The device is matched with a simple and friendly man-machine interaction interface, and the speed of the wheel can be measured very conveniently.

Disclosure of Invention

The invention aims to provide a wheel speed measuring device based on an AVR singlechip, which is realized by the following technical scheme:

the hardware part, the connection relation of each part is: the power supply module provides working power supply for the AVR single chip microcomputer, the switch type Hall sensor and the over-range alarm module; the output of the switch type Hall sensor is directly connected to an input unit of the AVR singlechip; the AVR singlechip is connected with the over-range alarm module through a specific I/O interface; the serial port of the AVR singlechip is connected with the upper computer.

The AVR singlechip is an ATmegal28 minimum system and comprises a power supply circuit, a reset circuit, an ISP download interface circuit and an I/O unit. The AVR singlechip processes the output pulse of the switch type Hall sensor, and when the switch type Hall sensor generates the output pulse, an input capturing module of the AVR singlechip can capture the input in time; the angular velocity of the wheel can be calculated by measuring the time interval between two adjacent pulses and the number of magnetic poles matched with the switch type Hall sensor, and the linear velocity of the wheel can be further obtained by combining the diameter of the wheel.

The output voltage of the power supply module is 5V/DC and is provided by a simple DC/DC module.

The model of the switch type Hall sensor is AH04E, the working voltage range is 3.8V-30V/DC, and 5V direct current is adopted for power supply.

The over-range alarm module is a simple buzzer and an alarm indicator lamp, the frequency of the buzzer is 50Hz, and the working voltage is 5V; the alarm indicator lamp is an LED lamp, and the working voltage is 5V.

The software part is used for programming a singlechip program, processing the signal captured by the AVR singlechip, calculating the angular velocity and the linear velocity of the wheel, and comparing the angular velocity and the linear velocity with a set threshold value to determine whether to give an alarm control signal or not.

And designing a LABVEW upper computer interface to facilitate the user to set parameters and read the parameters, wherein the parameter setting comprises wheel diameter setting and alarm threshold setting, and the parameter reading comprises the reading of wheel angular speed, wheel linear speed and output pulse waveforms of the switch type Hall sensor. The upper computer displays the content of the output pulse waveform, the wheel diameter, the wheel linear velocity, the wheel angular velocity and the alarm threshold of the switch type Hall sensor, and the number of magnetic poles matched with the switch type Hall sensor. The upper computer can also store the displayed data and the oscillogram in real time during running so as to facilitate further analysis.

The invention has the beneficial effects that: the angular velocity and the linear velocity of the wheel can be rapidly measured, the device is suitable for wheels with various diameters, and is convenient to install and disassemble and good in economic benefit.

Drawings

Fig. 1 is a functional block diagram of the speed measuring device system.

Fig. 2 is a schematic view of the installation of the switching hall sensor.

Fig. 3 is a flow chart of the software program of the speed measuring device.

Detailed Description

The invention provides a wheel speed measuring device based on an AVR single chip microcomputer.

The invention is further described with reference to the following figures and detailed description.

Fig. 1 is a functional block diagram of a velocity measurement device system. The power supply module provides working power supply for the AVR single chip microcomputer, the switch type Hall sensor and the over-range alarm module; the output of the switch type Hall sensor is directly connected to an input unit of the AVR singlechip; the AVR singlechip is connected with the over-range alarm module through a specific I/O interface; the serial port of the AVR singlechip is connected with the upper computer. The AVR singlechip adopted in the invention is an ATmegal28 minimum system, and comprises a power supply circuit, a reset circuit, an ISP download interface circuit and an I/O unit.

Fig. 2 is a schematic view of the installation of the switching hall sensor. The switched hall sensor is unipolar and rotates with respect to the wheel, while the magnetic pole is mounted on the rotating wheel and is stationary with respect to the wheel. When the wheel rotates, the magnetic pole rotating along with the wheel continuously faces the Hall sensor, so that the Hall sensor outputs a series of pulses. The AVR singlechip processes the output pulse of the switch type Hall sensor, and when the switch type Hall sensor generates the output pulse, the input capturing pin of the AVR singlechip can capture the input in time; the angular velocity of the wheel can be calculated by measuring the time interval between two adjacent pulses and the number of magnetic poles matched with the switch type Hall sensor, and the linear velocity of the wheel can be further obtained by combining the diameter of the wheel.

Fig. 3 is a flowchart of the software program of the speed measuring device. Firstly, initializing the state of an AVR singlechip, and then continuously detecting the output of a switch type Hall sensor by the AVR singlechip and calculating the speed of a wheel; meanwhile, the AVR singlechip polls an instruction sent by the upper computer and performs different operations according to different instructions, such as setting a measuring range, uploading a measuring result and a pulse waveform; when the measured result exceeds the measuring range, the AVR single chip microcomputer gives out a control signal to drive the acousto-optic alarm.