Car reversal radar that automatically modifies the sensor scanning range and method of the same

• US 20080094193A1
• Filed: 10/24/2006
• Published: 04/24/2008
• Est. Priority Date: 10/24/2006
• Status: Active Grant

• Current Assignee: Coligen Corp.
• Original Assignee: Shih-Hsiung Li
• Inventors: Li, Shih-Hsiung
• Granted Patent: US 7,567,168 B2
• Time in Patent Office: Days
• US Class Current: 340/435
• CPC Class Codes: G01S 15/931 of land vehicles
• CPC Class Codes: G08G 1/16 Anti-collision systems road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08
• CPC Class Codes: G08G 1/168 Driving aids for parking, e.g. acoustic or visual feedback on parking space

Abstract

A car reversal radar automatically modifies the sensor scanning range and the method of the same. The car reversal radar includes a central processing unit that has predetermined compensation value and threshold distance. When the car reversal radar starts, its surrounding environment is recorded into an initial detecting value. The initial detecting value is compared with a subsequent detecting value recorded for the environment when the car is being backed. When the subsequent detecting value is greater than the sum of the initial detecting value and the compensation value, the distance between an obstacle and the ultrasonic sensor of the car is compared with the threshold distance. If the former is greater than the latter, the compensation value is increased. Therefore, the obstacle has to even closer to the ultrasonic sensor to reduce the sensitivity of the ultrasonic sensors at the tail and to prevent incorrect actions.

Claims

1. A method of automatically modifying the sensor scanning range of a car reversal radar for the central processing unit (CPU) of a car reversal radar, comprising the steps of:

predetermining compensation values for the ultrasonic sensors and a threshold distance;

when the car reversal radar starts, sending out ultrasonic waves from the ultrasonic sensors to detect any obstacle and obtaining initial sensing results from the ultrasonic sensors;

storing each of the initial sensing results as an initial sensing value;

continuously detecting obstacles using the ultrasonic sensors, obtaining a plurality of subsequent sensing results from the ultrasonic sensors;

storing each of the subsequent sensing results as a subsequent sensing value;

when the subsequent sensing value of any of the ultrasonic sensors is greater than the corresponding “

initial sensing value+compensation value,”

determining that an obstacle is detected and computing the actual distance between the obstacle and the ultrasonic sensor; and

if the actual distance between the obstacle and the ultrasonic sensors on both sides at the back of the car is greater than the threshold distance, increasing the compensation value to reduce the sensitivity thereof.

2. The method of claim 1, wherein the CPU is an ATMega8 microprocessor.

3. A car reversal radar that automatically modifies its sensor scanning range, comprising:

a CPU;

a memory unit connected to the CPU;

an ultrasonic wave transceiving module, which is used to emit and receive ultrasonic waves, and including a plurality of sensor drivers and a plurality of ultrasonic sensors;

wherein each of the ultrasonic sensors is coupled to the CPU via one of the sensor drivers and the CPU controls to the ultrasonic sensors to send out ultrasonic waves;

a signal amplifying module, which is connected between the CPU and the ultrasonic transceiving module for amplifying the signals received by the ultrasonic sensors and then sending them to the CPU; and

a warning module, which is connected to the CPU for notifying the driver about the obstacle.

4. The car reversal radar of claim 3, wherein the ultrasonic transceiving module further includes a multiplexer connected to the CPU, the sensor drivers, and the signal amplifying module, and the multiplexer selects to send signals for amplification into the signal amplifying module.

5. The car reversal radar of claim 3, wherein the warning module includes a display unit and a sound warning unit with the display unit coupling to the CPU via a display driver and the sound warning unit being a buzzer coupling to the CPU via a sound driver.

6. The car reversal radar of claim 3, wherein the memory unit is built in the CPU.

7. The car reversal radar of claim 4, wherein the memory unit is built in the CPU.

8. The car reversal radar of claim 5, wherein the memory unit is built in the CPU.

9. The car reversal radar of claim 6, wherein the CPU is an ATMega8 microprocessor.

10. The car reversal radar of claim 7, wherein the CPU is an ATMega8 microprocessor.

11. The car reversal radar of claim 8, wherein the CPU is an ATMega8 microprocessor.