CN107463174B - Infrared ranging guidance method applied to the follow-up car - Google Patents

Abstract

The infrared distance measurement guiding method is applied to the follow-up trolley, and the method utilizes a module built by an infrared distance measurement sensor to detect the position information of a follow-up object in real time so as to realize that the follow-up trolley is guided by a moving object within a certain range; the method comprises the following specific steps: (1) setting two infrared distance measuring sensors on the trolley so as to form an infrared distance measuring sensing device, (2) establishing a two-dimensional coordinate system between the trolley and the following object, continuously scanning corresponding ranges by the sensors at a certain frequency, and recording initial position information of the following object; (3) the trolley moves according to the changed position information so as to accurately judge the moving position, direction and speed of the following object, realize the function of moving along with the target at any time and avoiding the front obstacle. The invention mainly realizes the purpose that the trolley can accurately judge the moving position, direction and speed of the target object, and simultaneously realizes the functions of following the target to move at any time and avoiding the front obstacle.

Description

Infrared ranging guidance method applied to the follow-up car

technical field

The invention relates to a technology for real-time detection of the position information of a following object by using a module constructed by an infrared ranging sensor, and is especially suitable for a follow-up trolley which can be guided by a moving object within a certain range.

Background technique

The control methods of the smart car include remote control, voice control, etc., but these methods all have the drawback that the position information of the following object cannot be accurately obtained.

SUMMARY OF THE INVENTION

Purpose of invention:

The invention provides an infrared ranging guidance method on a follow-up trolley, which aims to solve the problems existing in the past, and is a technology for real-time detection of the position information of a target object by a module constructed by an infrared ranging sensor.

Technical solutions:

An infrared ranging guidance method applied to a follow-up trolley is characterized in that: the method utilizes a module constructed by an infrared ranging sensor to detect the position information of a follow-up object in real time, so as to realize that the follow-up car is guided by a moving object within a certain range; The specific steps of the method are as follows:

(1) Set two infrared ranging sensors on the car to form an infrared ranging sensor device. The infrared ranging sensor is based on the principle of triangulation and emits an infrared beam through an infrared transmitter. When an object is encountered, the beam will reflect After returning, the reflected infrared light is received by the receiver on the trolley. After the sensor uses the CCD detector to detect the time difference data between the emission and reception, the offset value is calculated and output in the form of voltage by the signal processor. , using the triangular relationship and geometric relationship to calculate the distance from the sensor to the object;

(2) Using an infrared ranging sensor device constructed by two infrared ranging sensors on the trolley, a two-dimensional coordinate system is established between the trolley and the following object. The sensor continuously scans the corresponding range at a certain frequency, and records the tracking object Initial position information, when the following object moves, the changed position information outputs the changed voltage value, and the car can sense the change of the position information of the following object;

(3), the successive approximation AD converter is used to convert the voltage analog information measured by the sensor into its corresponding digital information and send it to the central processing unit. According to the pre-programmed settings, the car and the object always keep the initial value Therefore, the car moves according to the changed position information, so as to accurately judge the moving position, direction and speed of the following object, and realize the function of following the target movement at any time and avoiding the obstacles in front.

(2) In step 2, a two-dimensional coordinate system is established by the distance between the follow-up car and the target object measured by multiple infrared ranging sensors, and the position and direction of the target object are determined to realize the follow-up of the follow-up car.

In order to make the infrared ranging sensor device detect the largest range of the following object, the overlapping area that the two infrared ranging sensors can scan is required to be the largest;

The specific operations are as follows:

①. Use the left and upper sides of the car as the X and Y axes to establish a Cartesian coordinate system. The placement of the two infrared ranging sensors A and B is based on the fact that the red ranging range is at least 10 cm, and the A sensor is placed at the center of the circle, and the B sensor is placed below the Y axis at a distance of 10 cm from the origin;

2. According to the calculation, when the maximum allowable angles of the two infrared ranging sensors A and B are the same, the overlapping area of the A and B sensors is the largest;

3. Determine the placement angle of the A and B sensors, d is 90°, and the overlapping area of A and B is 0 at this moment; rotate sensor A clockwise, and the overlapping area increases until d is 135°, and the right side of sensors A and B The sides are completely coincident, and the overlapping area is the largest at this time; when the sensor A continues to rotate clockwise, the overlapping area will gradually decrease.

④ Combine the results obtained in the above steps:

The equation for a circle with center B:

dx ² +(y+10) ² =6400 (1)

The equation of line AB:

y=xtand (2)

From (1) and (2) we get

x ² +x ² tand ² +100+20xtand=6400 (3)

D: point x-axis coordinate

(1+tand ² )x ² +20dtanx-6300=0 (4)

Bring (3) into (4) to get

Among them, S is the overlapping area of sensors A and B, d is the angle from the left side of sensor A to the positive half-axis of the X-axis, and x is the maximum range of the infrared ranging sensor.

If the angle d is determined, the overlapping area of the sensors A and B increases with the increase of the maximum range x of the infrared ranging.

Let x be 80dm and d be 135° when the overlapping area is the largest, S _max =3291.7cm ² .

Advantage effect:

The invention adopts the follow-up mode to control the car, the car can accurately obtain the position information of the following object, judge the position and direction of the target object, and realize the follow-up car to follow the target object to move.

Two infrared ranging sensors are built on the trolley to form an infrared ranging sensing device. A non-standard two-dimensional coordinate system is established between the trolley and the following object, and the initial position information is recorded. When the object moves, the changed position information is output. The voltage value, and then the A/D converter of the successive approximation method is used to convert the output voltage value into a corresponding digital signal and transmit it to the central processing unit. The object always maintains the initial position, so the car moves according to the changed position information.

The transmitter in the infrared ranging sensor emits infrared rays, and is received by the receiver when it encounters the reflection of obstacles. The sensor uses the CCD detector to detect and calculate the time difference data between the emission and reception. form output, and then use the A/D converter of successive approximation method to convert the output voltage value into its corresponding digital signal. Two infrared ranging sensors are used to build an infrared ranging sensing device on the trolley, a two-dimensional coordinate system is established between the trolley and the following object, and the initial position information is recorded. When the object moves, the changed position information outputs the changed voltage value. , the car gets the change of the position information of the following object. According to the preset program setting, the car and the object always maintain the initial position, so the car moves according to the changed position information to accurately judge the moving position, direction and speed of the following object. Realize the function of following the target movement at any time and avoiding obstacles in front.

A two-dimensional coordinate system is established through the distance between the follow-up car and the target object measured by multiple infrared ranging sensors, and the position and direction of the target object are determined to realize the follow-up of the follow-up car.

Through the equipped infrared ranging sensor, it senses whether there is an obstacle ahead, so that the follow-up car can automatically adjust the movement direction, stay away from the obstacle, intelligently respond to obstacle avoidance in complex environments, and realize the obstacle avoidance of the follow-up car. Through the equipped infrared ranging module, the change of the moving state of the follower object is sensed, so that the follower car changes in real time with the change of the speed of the target object, so as to ensure the relative distance between the follower car and the target object, and realize the followability of the follower car.

To sum up, the present invention mainly realizes the purpose that the trolley can accurately determine the moving position, direction and speed of the target object, and also realizes the function of following the target movement at any time and avoiding obstacles in front.

Description of drawings

1 is a schematic diagram of a certain target object C of the present invention on the coordinate axis;

Fig. 2 is the schematic diagram of successive approximation AD converter;

3 is a schematic diagram of the position of the two infrared ranging sensors of the present invention when the placement angle is 90°;

4 is a schematic diagram of the position of two infrared ranging sensors of the present invention when the placement angle is 135°;

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings:

In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention are described below clearly and completely.

The infrared ranging sensor uses the principle that the intensity of the reflection of the infrared signal is different depending on the distance of the obstacle. The distance is short, the reflected light is strong, and the distance is far, the reflected light is weak, to detect the distance of the obstacle. The infrared ranging sensor has a pair of infrared signal transmitting and receiving diodes. The transmitting tube transmits infrared signals of a specific frequency, and the receiving tube receives infrared signals of this frequency. The infrared ranging sensor is based on the principle of triangulation. The infrared transmitter emits an infrared beam at a certain angle. When the infrared detection direction encounters an obstacle, the reflected signal is detected by the CCD detector, and the offset value is obtained. Using the triangular relationship The distance between the sensor and the target object can be calculated from the geometric relationship, and the data processed by the signal processor is output in the form of voltage, and then the A/D conversion chip of the successive approximation method is used to convert the output voltage value into its corresponding digital signal .

Two infrared ranging sensors are used to build an infrared ranging sensing device on the trolley, and a two-dimensional coordinate system is established between the trolley and the following object. The sensor continuously scans the corresponding range at a certain frequency. When an object appears, it can collect Different distance information, when the object moves, the position information received by the two sensors also changes. This constantly changing distance information directly affects the change of the voltage value output by the sensor. Then the AD converter converts the voltage analog information measured and output by the sensor into digital information and sends it to the central processing unit. The car with the central processor first receives the initial position information of the object. When the object moves, the car understands the change of the position information of the following object. According to the pre-programmed settings, the car and the object always keep the initial position information, so the car changes according to the change. To achieve accurate judgment of the moving position, direction, and speed of the following object, to achieve the function of following the target movement at any time and avoiding obstacles in front.

Fig. 1 is a schematic diagram of a certain target object C of the present invention on the coordinate axis, as shown in Fig. 1, a Cartesian coordinate system is established with the upper left vertex of the trolley as the origin O, and the coordinates of a certain point C within the range that can be recognized by sensors A and B are ( x, y), the distance from the point O is L, and the angle between the positive semi-axis of the x-axis is e, so the initial position information of the object can be obtained. In Figure 1, when a point C moves, the distance and angle from point C to the origin O are changing, and the output voltage value of the corresponding sensor is changing. The A/D converter using the successive approximation method converts the changing voltage value into a change According to the preset program setting, the car and the object always maintain the initial position information, so the car moves according to the changed position information to realize the guidance of moving objects, intelligent car follow-up function.

Figure 2 is a schematic diagram of the successive approximation AD converter. As shown in Figure 2, the successive approximation A/D converter is composed of a comparator, a D/A converter, a buffer register and a control logic circuit. The basic principle is to test and compare from high position to low position one by one, as if using a balance to weigh objects, and increase or decrease weights step by step from heavy to light to test. The conversion process of the successive approximation method is: clear the bits of the successive approximation register during initialization; when the conversion starts, first set the highest position of the successive approximation register to 1, send it to the D/A converter, and send the analog quantity generated after the D/A conversion into the The comparator, called Vo, compares the analog quantity Vi to be converted into the comparator. If Vo<Vi, this bit 1 is reserved, otherwise it is cleared. Then set the second highest bit of the successive approximation register to 1, send the new digital quantity in the register to the D/A converter, and compare the output Vo with Vi. If Vo<Vi, the bit 1 is reserved, otherwise it is cleared. Repeat this process until the lowest register bit is approached. After the conversion, the digital quantity in the successive approximation register is sent to the buffer register, and the output of the digital quantity is sent to the central processing unit for processing.

In order for the infrared ranging sensor device to detect the maximum range of the following object, the overlapping area that the two infrared ranging sensors can scan is required to be the largest.

The specific operations are as follows:

①. Use the left and upper sides of the car as the X and Y axes to establish a Cartesian coordinate system. The placement positions of the two infrared ranging sensors A and B are shown in Figure 1. According to the minimum range of the infrared ranging sensor is 10 cm, it is determined that the A sensor is placed at the center of the circle, and the B sensor is placed below the Y axis at a distance of 10 cm from the origin. ;

2. According to the calculation, when the maximum allowable angles of the two infrared ranging sensors A and B are the same, the overlapping area of the A and B sensors is the largest;

3. Figure 3 is a schematic diagram of the position of the two infrared ranging sensors of the present invention when the placement angle is 90°. As shown in Figure 3, the placement angle of the A and B sensors is determined, and d is 90°. At this moment, the overlap of A and B The area is 0; when sensor A is rotated clockwise, the overlapping area increases until as shown in Figure 4, d is 135°, the right sides of sensors A and B are completely overlapped, and the overlapping area is the largest at this time; when sensor A continues to rotate clockwise, The overlapping area will gradually decrease.

④ Combine the results obtained in the above steps:

The equation for a circle with center B:

dx ² +(y+10) ² =6400 (1)

The equation of line AB:

y=xtand (2)

From (1) and (2) we get

x ² +x ² tand ² +100+20xtand=6400 (3)

D: point x-axis coordinate

(1+tand ² )x ² +20dtanx-6300=0 (4)

Bring (3) into (4) to get

Among them, S is the overlapping area of sensors A and B, d is the angle from the left side of sensor A to the positive half-axis of the X-axis, and x is the maximum range of the infrared ranging sensor.

If the angle d is determined, the overlapping area of the sensors A and B increases with the increase of the maximum range x of the infrared ranging.

Let x be 80dm and d be 135° when the overlapping area is the largest, S _max =3291.7cm ² .

Claims (3)

1. The infrared distance measurement guiding method applied to the follow-up trolley is characterized in that: the method utilizes a module built by an infrared distance measuring sensor to detect the position information of a following object in real time so as to realize that the following trolley is guided by a moving object within a certain range; the method comprises the following specific steps:

(1) the infrared distance measuring sensor transmits an infrared light beam through an infrared transmitter based on the principle of triangulation, the light beam is reflected back when encountering an object, the reflected infrared light is received by a receiver on the trolley, the sensor detects time difference data between transmission and reception by using a CCD (charge coupled device) detector, calculates to obtain an offset value, outputs the offset value in a voltage form after being processed by a signal processor, and calculates to obtain the distance from the sensor to the object by using a triangular relation and a geometric relation;

(2) the method comprises the following steps of establishing a two-dimensional coordinate system between a trolley and a following object by utilizing an infrared distance measuring sensing device formed by two infrared distance measuring sensors on the trolley, continuously scanning a corresponding range by the sensors at a certain frequency, recording initial position information of the following object, outputting a changed voltage value by the changed position information when the following object moves, and changing the position information of the sensor of the trolley to the following object;

(3) the changed voltage analog quantity information measured by the sensor is converted into digital quantity information corresponding to the changed voltage analog quantity information by adopting a successive approximation type AD converter, and the digital quantity information is sent to a central processing unit, and the trolley and the object are always kept at the initial position according to the preset program setting, so that the trolley moves according to the changed position information, the moving position, the direction and the speed of a following object are accurately judged, the function of following the target at any time and avoiding a front obstacle is realized;

in order to maximize the range of the infrared distance measuring sensor device capable of detecting the following object, the overlapped area which can be scanned by the two infrared distance measuring sensors is required to be the largest;

the specific operation is as follows:

firstly, establishing a rectangular coordinate system by taking the left side and the upper side of the trolley as X, Y axes; the placement positions of the two infrared ranging sensors A, B are that the sensor A is placed at the center of a circle according to the fact that the range of the infrared ranging range is 10 cm at the minimum, and the sensor B is placed at the position which is 10 cm away from the original point below the Y axis;

secondly, according to calculation, when the maximum allowable angles of the two infrared ranging sensors A, B are the same, the overlapping area of the A, B sensors is the maximum;

thirdly, determining the placement angle of the A, B sensor, wherein d is 90 degrees, and the overlapping area of A, B is 0 at the moment; rotating the sensor A clockwise, increasing the overlapping area until d is 135 degrees, completely overlapping the right side edge of the sensor A, B, and then maximizing the overlapping area; when the sensor A continues to rotate clockwise, the overlapping area is gradually reduced;

combining the results obtained in the steps:

equation of circle with B as center:

x²+(y+10)²＝6400 (1)

equation for line AB:

y＝xtand (2)

is prepared from (1) and (2)

x²+x²(tand)²+100+20xtand＝6400 (3)

Wherein S is the overlapping area of the sensor A, B, d is the angle from the left side of the sensor A to the positive half shaft of the X axis, and X is the maximum range of the infrared distance measuring sensor;

if the angle d is determined, the overlap area of the sensor A, B increases as the maximum range x of infrared ranging increases.

2. The infrared distance measurement guiding method applied to the follow-up carriage as claimed in claim 1, wherein: (2) in the step, a two-dimensional coordinate system is established through the distance between the follow-up trolley and the target object measured by the plurality of infrared distance measuring sensors, the position and the direction of the target object are judged, and the follow-up property of the follow-up trolley is realized.

3. The infrared distance measurement guiding method applied to the follow-up carriage as claimed in claim 1, wherein: the maximum overlap area is obtained when x is 80dm and d is 135 DEG, S_max＝3291.7cm²。

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