CN102023003A - Unmanned helicopter three-dimensional positioning and mapping method based on laser detection and image recognition - Google Patents

Abstract

The invention relates to an unmanned helicopter three-dimensional positioning and mapping method based on laser detection and image recognition, which belongs to the technical field of application of unmanned aerial vehicles. A distance measurement sensor based on laser detection and image recognition, an altimetric sensor and a flight control computer are comprised, wherein the distance measurement sensor consists of a vehicle-mounted camera and a laser emitter and used for detecting the distance from the unmanned helicopter to obstacles around. The distance measurement sensor is used for detecting and measuring distance for the around environment of the unmanned helicopter by means of changing the angle of pitch and the angle of yaw. The altimetric sensor is used for measuring the flight altitude from the unmanned helicopter to the ground. The distance measurement data obtained from the measurement under different angles of altitude, angles of yaw and flight altitudes can realize three-dimensional synchronous positioning and mapping of unknown environment by the unmanned helicopter. In the invention, the around environment can be rapidly, simply and reliably detected during the flying by carrying the distance measurement sensor based on laser detection and image recognition on the unmanned helicopter.

Description

Three-dimensional positioning and mapping method for unmanned helicopter based on laser detection and image recognition

technical field

The invention is a method for positioning and detection of an unmanned helicopter in a complex unknown environment, and can realize three-dimensional synchronous positioning and surveying and mapping of the unmanned helicopter in a complex unknown environment with high precision. It is mainly used in technical fields such as aerospace, drones and robots.

Background technique

Three-dimensional simultaneous positioning and mapping in complex and unknown environments is one of the important intelligent functions of unmanned helicopters. Its main purpose is to complete positioning, detection and mapping in unknown environments, and to assist unmanned helicopters in highly autonomous flight. Traditional three-dimensional simultaneous positioning and mapping flights are mostly completed with the assistance of terrain detection radar. Due to the heavy weight of terrain detection radar, small unmanned helicopters are difficult to equip. Therefore, unmanned helicopters usually use lidar. However, lidar can only obtain two-dimensional positioning and mapping data. If three-dimensional positioning and detection are required, the unmanned helicopter must change the flying height to complete positioning and detection at different heights. For unmanned helicopters flying in unknown environments, changing the flight altitude may cause collisions with obstacles. In addition, lidar is expensive and heavy, which is not the best choice for unmanned helicopters.

Because ordinary unmanned helicopters usually have onboard cameras, altitude sensors and flight control computers. On the basis of the above equipment, the present invention makes a laser transmitter and an airborne camera form a distance measuring sensor based on laser detection and image recognition by adding a laser transmitter. Subsequently, with the cooperation of the altitude sensor and the flight control computer, by synchronously deflecting the onboard camera and laser transmitter in the pitch direction and yaw direction, the distance and distance between the unmanned helicopter and the surrounding obstacles can be detected and obtained in real time. Height from the ground. According to the detection distance, detection angle and flight height, the database of the distance between the unmanned helicopter and the surrounding environment and the detection angle can be obtained, so as to obtain a three-dimensional digital map of the unknown environment around the unmanned helicopter, and then realize three-dimensional simultaneous positioning and mapping. Compared with traditional terrain detection radar (100Kg level), the weight of the present invention is much lighter (50g level), and can be carried by unmanned helicopter, especially small unmanned helicopter; Compared with laser radar, the present invention does not need To change the flying height of the unmanned helicopter, only the pitch angle and yaw angle of the laser transmitter can be changed to realize three-dimensional synchronous positioning and detection, which can greatly increase the flight safety of the unmanned helicopter. In addition, the present invention makes full use of the original airborne equipment of the unmanned helicopter, and only needs to add a laser transmitter. Therefore, the present invention has the advantages of simple structure, low cost, and easy modification, and does not add complicated and expensive hardware, mainly focuses on software upgrades, adds little weight to unmanned helicopters, and can be used to assist unmanned helicopters in highly autonomous flight.

Contents of the invention

The purpose of the present invention is to provide a method for unmanned helicopters to realize high-precision three-dimensional synchronous positioning and surveying and mapping in complex and unknown environments.

The present invention is characterized in that it contains: a ranging sensor based on laser detection and image recognition, a height sensor and a flight control computer, wherein the ranging sensor based on laser detection and image recognition is composed of an airborne camera and a laser transmitter for To detect the distance D between the unmanned helicopter and surrounding obstacles, the height sensor is used to measure the flying height H of the unmanned helicopter, where:

By changing the pitch angle Θ and the heading angle Ψ of the laser transmitter, the laser transmitter uses the laser it emits to scan and detect the surrounding environment of the unmanned helicopter; when the laser irradiates the surrounding obstacles, it will generate laser light point; the airborne camera captures the laser light spot, and sends the video to the flight control computer; the flight control computer can calculate the distance D between the unmanned helicopter and the surrounding obstacles according to the position of the light spot in the video; the flight control computer Through the height sensor, the flight height H of the unmanned helicopter from the ground can be known; according to the distance D from the obstacle measured by the laser transmitter under the conditions of various pitch angles Θ, heading angle Ψ, and flight height H, the surrounding area of the unmanned helicopter can be obtained. The three-dimensional digital map of the unknown environment, so as to realize three-dimensional simultaneous positioning and mapping; and the shielding of the laser emitted by the laser transmitter by the fuselage of the unmanned helicopter can be solved by the yaw flight of the unmanned helicopter.

The invention has the advantages of simple structure, low cost and easy refitting, and does not add complicated and expensive hardware, mainly focuses on software upgrades, adds little weight to unmanned helicopters, and can be used to assist unmanned helicopters to carry out high autonomy morphed flight. Compared with traditional terrain detection radar (100Kg level), the weight of the present invention is much lighter (50g level), and can be carried by unmanned helicopter; Compared with laser radar, the present invention does not need to change the flight height of unmanned helicopter , Just change the pitch angle and yaw angle of the laser transmitter to realize three-dimensional synchronous positioning and detection, which can greatly increase the flight safety of unmanned helicopters. In addition, the present invention makes full use of the original airborne equipment of the unmanned helicopter, and only needs to add a laser transmitter.

Description of drawings

Fig. 1 is a schematic diagram (side view) of a three-dimensional positioning and mapping method for an unmanned helicopter based on laser detection and image recognition.

Fig. 2 is a schematic diagram (top view) of the three-dimensional positioning and mapping method of the unmanned helicopter based on laser detection and image recognition.

In Figure 1 and Figure 2, 1. Unmanned helicopter, 2. Flight control computer, 3. Ranging sensor based on laser detection and image recognition, 4. Airborne camera, 5. Laser transmitter, 6. Laser, 7 .Laser light spot on the target, 8.Height sensor.

Detailed ways

The three-dimensional positioning and mapping method of the unmanned helicopter based on laser detection and image recognition requires the cooperation of a distance measuring sensor (3), an altitude sensor (8) and a flight control computer (2) based on laser detection and image recognition. Among them, the ranging sensor (3) based on laser detection and image recognition is used to detect the distance D between the unmanned helicopter (1) and the surrounding obstacles, and the height sensor (8) is used to measure the flight of the unmanned helicopter (1). At height H, the flight control computer (2) is used to calculate sensor data, and complete the three-dimensional positioning and mapping of the unmanned helicopter (1) in a complex and unknown environment.

The ranging sensor (3) based on laser detection and image recognition is composed of an airborne camera (4) and a laser transmitter (5). The airborne camera (4) and the laser emitter (5) deflect synchronously as a whole, and transmit the captured video to the flight control computer (2) in real time. According to the position of the laser spot (7) in the video, the flight control computer (2) can calculate the distance D between the unmanned helicopter (1) and surrounding obstacles.

By changing the pitch angle Θ and the heading angle Ψ of the laser transmitter (5), the laser transmitter (5) scans the surrounding environment of the unmanned helicopter (1) using the laser (6) it emits. When the laser light (6) irradiates the surrounding obstacles, laser light spots (7) will be generated on the surface thereof. The on-board camera (4) captures the laser spot (7), and sends the video to the flight control computer (2). The flight control computer (2) can calculate the distance D between the unmanned helicopter (1) and the surrounding obstacles according to the position of the laser spot (7) in the video in the camera plane. The flight control computer (2) can learn the flying height H of the unmanned helicopter (1) from the ground through the height sensor (8).

Inevitably, the fuselage of the unmanned helicopter (1) will block the laser (6) emitted by the laser emitter (5), which can be solved by the yaw flight of the unmanned helicopter (1).

According to the laser transmitter (5) under each pitch angle Θ, heading angle Ψ and unmanned helicopter (1) flight height H conditions, the measured distance D from obstacles can be obtained from the unmanned helicopter (1) to the surrounding environment Database of distances and detection angles. Thereby, a three-dimensional digital map (spherical coordinates) of the unknown environment around the unmanned helicopter (1) can be obtained, thereby realizing three-dimensional synchronous positioning and mapping of the unmanned helicopter (1) in the unknown environment.

Claims (1)

1. based on the depopulated helicopter three-dimensional localization and the mapping method of laser acquisition and image recognition, it is characterized in that, contain: based on distance measuring sensor, height sensor and the flight-control computer of laser acquisition and image recognition, wherein, distance measuring sensor based on laser acquisition and image recognition is made up of airborne video camera and generating laser, be used to survey the distance D between depopulated helicopter and the peripheral obstacle, height sensor is used to measure the flying height H of depopulated helicopter, wherein:

Relative position between airborne video camera and the generating laser is fixed, and can wholely rotate synchronously; By rotation, can change the course angle Ψ of the angle of pitch Θ of generating laser based on the distance measuring sensor of laser acquisition and image recognition around pitch axis and course axle; The course angle Ψ of angle of pitch Θ by changing generating laser, generating laser utilizes its emitted laser that the surrounding environment of depopulated helicopter is carried out scanning probe; When laser radiation to around barrier the time, can produce laser spot on its surface; Airborne video camera photographs laser spot, and video is sent to flight-control computer; Flight-control computer can calculate the distance D of depopulated helicopter apart from this barrier according to the position of luminous point in this video; Flight-control computer can be known the flying height H of depopulated helicopter apart from ground by height sensor; According to generating laser under each angle of pitch Θ, course angle Ψ and unmanned helicopter flight height H condition, measure apart from obstacle distance D, can obtain depopulated helicopter apart from the distance of surrounding environment and the database of detection angle, thereby obtain the depopulated helicopter Three-dimensional Numeric Map of circumstances not known on every side, and then realize three-dimensional synchronized positioning and the mapping of depopulated helicopter in circumstances not known; And the depopulated helicopter fuselage can solve by the yawed flight of depopulated helicopter blocking that generating laser institute emitted laser causes.

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