Automotive Ultrasonic Radar Rangefinder

By Devin
4 min read
Automotive-Ultrasonic-Radar-Rangefinder Laser Ranging

The automotive ultrasonic radar range finder is a device that detects obstacles at the rear of a car and can accurately measure the distance to the obstacle. It is composed of a radome (1), an ultrasonic sensor (9), a host box (10) and other components. It is installed on the automobile chassis (2) and is driven by a micro motor (6) to scan the radome (1) left and right. Therefore, it has the outstanding characteristics of ultra-long detection distance and elimination of blind spots. It is a high-performance and ideal automotive ultrasonic distance measuring instrument.

 

Automotive ultrasonic radar range finder

Figure 1

The vehicle ultrasonic radar rangefinderis composed of a radome (1), a chassis (2), an ultrasonic sensor (9), a host box (10) and other components. It is characterized in that the radome (1) is made of metal or plastic. The paraboloid is formed, the ultrasonic sensor (9) is fixed on its focus with a bracket (8), the mesh cover (15) is set in front of the radome, and the radome is inserted into the positioning seat (4) through the pivot shaft (5) and can be rotated and positioned The base (4) is fixed on the chassis (2), and the turbine (3) meshes with the motor shaft (7); the main box (10) is provided with a circuit board (14), a digital display (11), a button (12), etc. It is connected with the ultrasonic sensor (9) by wires (13). The circuit board (14) is provided with a time-sharing circuit and a motor control circuit. The micro motor (6) and the host box are also connected by wires. The beneficial effect is that the driving of the motor (6) can cause the radome (1) to rotate left and right, thereby eliminating detection blind spots on both sides of the rear of the vehicle, and due to the focusing effect of the radome paraboloid, the detection distance can be greatly extended.


Description of the drawings
Figure 1 is a schematic structural diagram of the utility model.

Figure 2 is a schematic diagram of the circuit of the present utility model.

 

Automotive ultrasonic radar range finder

Figure 2

Figure 3 is the control electrical diagram of the micro motor (6) of the present utility model.

 

 

Figure 3

Detailed ways

The working principle is as follows: B₁B₂ in Figure 2 is an ultrasonic sensor, B₁ is used for transmitting, and B₂ is used for receiving. You can also use one for both transmitting and receiving. Since they are placed at the focal point of the radome (1), the well-known parabolic properties allow B₂ (i.e. the sensor (9)) to absorb the energy collected by the parabolic section. This cross-sectional area can be hundreds to thousands of times larger than the cross-sectional area of the sensor itself, which greatly improves the signal-to-noise ratio of the receiving amplifier IC₁, thereby greatly increasing the detection distance, up to 30 meters or more.On the other hand, the present utility model can use lower ultrasonic frequencies because it utilizes the directional focusing effect of the parabolic radome (1). According to the propagation characteristics of ultrasonic waves, this is also beneficial to increasing the transmission distance of ultrasonic waves.Under the driving and forward and reverse rotation of the micro motor (6) and the functions of the transmission mechanism turbine (3), motor wheel (7), supporting shaft (5), and positioning seat (4), the radome (1) and The emitted ultrasonic beam scans left and right on the horizontal plane to eliminate blind spots and blind spots at the rear of the car.

Figure 2 consists of clock circuit, differential, shaping circuit, ultrasonic transmitting circuit, ultrasonic receiving circuit, RS flip-flop, counting and display circuit and time division circuit.


Press the measurement switch (12) (ie SK), pin 3 of IC₃CD4060 outputs a clock pulse of about 20HZ. On the one hand, it causes D₃ and D₄ to generate ultrasonic oscillation of 20KHz, and B₁ emits ultrasonic waves. On the other hand, it causes the IC₂CD4013RS trigger to be set. IC₄ 5G7225 starts counting.

When the ultrasonic wave is reflected back by the obstacle, it is converted into an electrical signal by B₂, which is amplified by IC₁741, D₆, and D₇ are shaped to reset IC₂ and act on IC₄ to latch the counting result and display it on the digital display to complete the measurement.

BG1, Ro, D, etc. form a time division circuit. Since the potentials of terminals 2 and 4 of D1 and D2 are in opposite phases, when B1 emits ultrasonic waves, BG₁ is turned off and IC1741 stops working. When B₁ stops transmitting, BG₁ is turned on and IC₁ works and amplifies the signal received by B1. This avoids misjudgment caused by B2 directly receiving the ultrasonic waves emitted by B1.

Figure 3 is composed of a single-variable dual power supply, a multivibrator, and an electronic switching circuit. IC1TDA2030, C₂, C₃ and other components constitute a single-variable dual power supply, outputting positive and negative 6 volt power supply for the micro motor (6) (i.e. MD). IC₂NE555, 3DK₂, R3, C₄ and other components constitute a multivibrator. Pin 3 outputs a square wave. After inversion by 3DG₆, the two points A and B alternately output positive pulses to trigger the electronic switches MRC₁ and MRC₂, thereby making the motor MD alternately positive and negative. Reverse rotation drives the radome (1) to rotate left and right to achieve ultrasonic back and forth scanning motion.

To sum up, we have introduced an ultrasonic detection device with ultra-long distance and eliminates blind spots and blind spots. It is an ideal high-performance automotive ultrasonic distance measuring instrument.

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