Split type hovercar involution method based on visual-mechanical module cooperative control

Abstract

The invention provides a split type hovercar involution method based on vision-mechanical module cooperative control. The folding system comprises a visual module, a mechanical auxiliary module and an integrated control system. Overall control of the integrated control system; the flight module is preliminarily positioned at the top of the automobile module based on a positioning system; the visual sensing processing module keeps the balance of the aircraft and controls the distance between the aircraft and an automobile through a horizontal sensor and a distance sensor respectively, so that accurate distance measurement is realized through a laser radar; the control system controls the aircraft and the automobile chassis to be pre-folded according to a feedback signal instruction attitude of the sensor and the laser radar; the mechanical riveting module assists the aircraft and the vehicle body to be accurately combined based on sliding groove positions preset at the bottom of the aircraft and the top of the vehicle. Based on the method, rapid folding of the split type hovercar under various topographic conditions can be achieved, the time needed by the folding process is shortened so as to prolong the flight endurance mileage, and the method has the advantages of being rapid in folding, convenient and fast to operate, wide in adaptive scene and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of land and air dual-purpose vehicles, and relates to a split flying car alignment method based on visual-mechanical module collaborative control. Background Art

[0002] The split flying car is a new type of modular dual-purpose vehicle for land and air, which can travel on the ground and take off and land vertically in the air, and has the ability to maneuver and flexibly overcome obstacles over long distances. The split design effectively solves the problem that the current electric aircraft has a short range and the ground transportation vehicles have insufficient obstacle-crossing ability. It has a wide range of application potential in personal travel, emergency rescue and cargo transportation, and can greatly improve the three-dimensional maneuverability of land and air collaborative tasks. The flight module mostly adopts an electric multi-rotor manned vertical take-off and landing aircraft, and the ground module usually adopts a high-mobility chassis to achieve strong off-road maneuverability. The flight module and the ground module share the cockpit. The flying car cockpit completes the driving functions of both the aircraft and the car. The module matching of the aircraft and the car chassis is a key process when the split flying car is driving. The accuracy and time required for module matching, as well as the complexity of the operation, have an important impact on the driving experience and the range of the aircraft. Whether the high driving comfort and long-duration flight process can be achieved is closely related to whether the modules can be matched autonomously and efficiently. However, the operation scenarios of split flying cars involve urban commuting, outdoor experience and emergency rescue, and the ground environment of the service terrain is complex. Compared with smooth urban roads, when the chassis module is aligned on warped terrain such as rugged roads, the tilted chassis makes it difficult for the flight module and the ground module to be accurately and quickly aligned, which often leads to deterioration of module alignment accuracy and increased alignment time, which in turn shortens the aircraft's cruising range and reduces driving comfort. Therefore, the difficulty of aligning the aircraft and ground modules of split flying cars in complex terrain environments restricts the improvement of the flying car's driving experience and service performance.

[0003] At present, in order to solve the problem of difficulty in quickly aligning the flight module and the ground module of a split flying car, the commonly used aligning structure / method is based on a mechanical locking mechanism. When the mechanical locking method is used for docking, the aligning of the flight module and the ground module is mostly achieved by structures such as hooks and slots, rods and slots, pins and pin slots. Properly increasing the number of locking structures and optimizing the distribution of structures can reduce the time required for the module aligning process to a certain extent. At the same time, presetting the sub-docking mechanism and the mother docking hole in the pre-alignment area can guide the rapid suction and module alignment between the sub / mother mechanisms. Using materials with mutual attraction and self-locking properties such as magnetic materials to make the aligning mechanism components can also promote the combination of the intended aligning surfaces. In addition to the mechanical locking mechanism, the split module aligning method at this stage also includes the rotation adaptive docking method proposed by Airbus around the POP UP flying car, which can achieve the alignment between modules in the principle verification stage.

[0004] However, the existing means cannot fundamentally solve the problem of the difficulty of docking between the flight module and the ground module of the split flying car in a complex terrain environment. The mechanical locking method has a complex structure, occupies a large space and has low structural efficiency. The position control of the sub-docking mechanism and the mother docking mechanism mainly relies on the manual operation and control of the driver and passengers, and it is difficult to achieve highly automated docking between the modules. More seriously, the current mechanical interlocking docking mechanism has pre-requirements for the posture and position of the intended docking surface due to the use of docking heads and hole structures, which is not suitable for ground scenes such as rugged mountains and post-earthquake disaster relief, resulting in an increase in the docking time between the flight module and the ground module in a complex ground environment and a reduction in the aircraft's cruising range. Although the use of magnetic materials and rotating adaptive mechanisms can accelerate the docking to a certain extent, it increases the weight of the aircraft and the mechanical adaptive structure is complex and the reliability needs to be improved. Therefore, it is difficult to effectively improve the efficiency of the docking between the flight module and the ground module of the split flying car, resulting in the latter becoming the main constraint on the improvement of the aircraft's cruising range and driving experience. Summary of the invention

[0005] The purpose of the present invention is to provide a split flying car assembly method based on visual-mechanical module coordinated control. The assembly system and assembly method are realized through the rapid positioning of the visual sensing processing module and the auxiliary coordination of the mechanical riveting module. Based on this method, the split flying car can be quickly assembled under various terrain conditions, shortening the time required for the assembly process to extend the flight range.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] The split flying car alignment method based on visual-mechanical module collaborative control includes the following steps:

[0008] Step 1: During the initial tracking process, the control system of the flight module plans the flight trajectory according to the coordinate information fed back by the ground vehicle module, assists the driver in controlling the flight to the predetermined location, and lowers the aircraft altitude according to the preset program until the module spacing reaches the optimal ranging range of the lidar.

[0009] Step 2: During the initial alignment process, the camera at the bottom of the flight module identifies multiple feature markers on the top of the car module and reconstructs the relative spatial position of the chassis, recorded as position A. The integrated control system calculates the three coordinates and inclination information of the chassis plane of the car module relative to the absolute horizontal plane at this time, and controls the flight attitude and quickly approaches position A with the goal of making the chassis plane of the aircraft and the chassis plane of the car module relatively parallel.

[0010] Step 3: Pre-alignment process, the flight module approaches position A at a relatively fast speed and gradually slows down when the module spacing is 1 to 1.5 meters. The integrated control system automatically plans the module alignment path and required time based on the preset algorithm. At the same time, the laser radar at the bottom of the flight module accurately measures the module spacing in real time and provides feedback. The control system continuously iterates and optimizes based on the feedback data to complete the pre-alignment between the flight module and the ground module.

[0011] Step 4: In the final mating process, when the distance between the mother-child mating surface of the car module and the flight module is 10-20cm, the control system further reduces the descent rate of the flight module and approaches the preset area at a rate of 1-3cm / s. When the modules are mated, the mother mating area at the bottom of the aircraft slides into the child mating area of ​​the car chassis in a riveted state, and the pins in the slide slot immediately lock and limit the module, and the mating is completed. The vehicle is then in the form of a car on the road.

[0012] Furthermore, the rapid and accurate alignment between the aircraft and the chassis of the car is achieved through the coordinated control of the visual module and the mechanical module. Under the overall planning of the integrated control system, the visual module completes the precise positioning and rapid approach between the aircraft and the chassis, and the mechanical module completes the rapid alignment and locking at close range.

[0013] Furthermore, the integrated control module of the docking system includes a variety of data processing and path planning algorithms, which can realize the automatic generation and evolution iteration of the trajectory within 10km between the aircraft and the car chassis. After the driver issues a docking command within the corresponding distance, the control module automatically generates the trajectory and then feeds back to the driver to assist the module in the initial tracking process of the docking.

[0014] Furthermore, the top of the vehicle module is provided with characteristic marking points at the support column, and a plurality of characteristic marking points are mapped to the top plane of the vehicle module. During the initial alignment process, the camera at the bottom of the flight module identifies the characteristic marking positions, reconstructs the relative spatial position (A) of the vehicle chassis, and calculates the three coordinates and inclination angle relative to the horizontal plane. The relevant coordinate information is the key reference for adjusting the attitude of the vehicle module.

[0015] Furthermore, the aircraft chassis attitude adjustment involved in the initial alignment process is intended to achieve the purpose of making the aircraft chassis parallel to the car chassis. For example, when the car chassis is in a scenario where it is tilted 10° along the XOY plane, the control system regulates the rotation speed of multiple rotors based on the reconstructed coordinate information, thereby tilting the aircraft to the corresponding inclination angle to achieve parallelism with the car chassis.

[0016] Furthermore, after the aircraft completes the attitude adjustment in the initial alignment step, the distance between the aircraft chassis and the aircraft chassis is 10 to 20 meters, and the aircraft approaches the automobile chassis within 30 seconds at a moving speed of 1 to 2 m / s.

[0017] Furthermore, the pre-alignment specifically refers to the alignment process when the distance between the aircraft and the car chassis is within 1.5 meters. At this time, the laser radar at the bottom of the aircraft starts to work. The laser radar collects the distance between the aircraft and the car chassis at a frame rate of 20 frames per second. The radar immediately feeds back the distance data obtained by precise ranging to the integrated control center, which adjusts and corrects the module pre-alignment process with a higher response frequency to achieve closed-loop trajectory control.

[0018] Furthermore, the final matching process refers to when the distance between the flight module and the automobile chassis is within 10 to 20 cm. At this time, the movement rate of the aircraft is controlled within 3 cm / s, and the parent matching area at the bottom of the aircraft gradually approaches the child matching area at the top of the automobile chassis. The module is naturally sucked in and matched by matching with the characteristic grooves. After the aircraft is in place, the pin in the slide groove is triggered to quickly lock and limit the module.

[0019] Furthermore, the fast alignment method includes four steps, initial tracking, initial alignment, pre-alignment and final alignment. Each step calls different modules according to the characteristics of the scene and is combined with a specific aircraft movement rate. For example, the initial tracking and initial alignment have a faster movement rate due to the large spacing, and the pre-alignment and final alignment processes use a lower aircraft movement rate to improve accuracy and ensure the alignment efficiency.

[0020] The split flying car alignment method based on the visual-mechanical module collaborative control adopts a split flying car alignment system, including a flight module and a ground module. The modules can be quickly and accurately aligned and reset under various terrain conditions such as urban flat roads and mountainous rugged roads, so as to extend the cruising range and improve the driving experience. The means to improve the module alignment rate and accuracy is to introduce the visual module and the mechanical module for collaborative control, and the alignment system as a whole includes the visual module, the mechanical auxiliary module and the integrated control system. The specific process is that the integrated control system is overall controlled; the flight module is initially positioned on the top of the car module based on the positioning system; the visual sensor processing module uses the horizontal sensor and the distance sensor to maintain the balance of the aircraft and control the distance from the top of the car respectively, and then uses the laser radar to accurately measure the distance; the control system uses the sensor and laser radar feedback signal to command the attitude control of the aircraft and the car chassis for pre-alignment; the mechanical riveting module assists the precise alignment of the aircraft and the car body based on the preset slide slots at the bottom of the aircraft and the top of the car.

[0021] Furthermore, the split flying car docking system has modular features, including a visual module, a mechanical auxiliary module and an integrated control system. The visual module is further composed of a laser radar, a distance sensor and a horizontal module sensor. The mechanical auxiliary module is specifically composed of a mother docking area at the bottom of the aircraft, a sub-docking area at the top of the chassis, and a latch-type locking mechanism. The integrated control system is responsible for receiving, processing and transmitting instructions, and adjusting and correcting the aircraft's attitude in real time based on the image and position information fed back by the visual module, so as to overall control the entire process of docking between the aircraft and the vehicle body.

[0022] The present invention has the following advantages:

[0023] 1) Rapid alignment and short time consumption. Using the rapid alignment method based on vision and mechanical coordination, the aircraft alignment process is divided into stages according to the distance, and the control system adjusts the aircraft movement speed according to the characteristics of each stage to improve the overall operation efficiency. Compared with the method of relying solely on mechanical alignment, it effectively reduces time consumption and extends the range.

[0024] 2) Adaptability to a wide range of terrains. The present invention can flexibly adjust the tilt angle of the aircraft to match the chassis position by identifying and reconstructing the chassis position in the initial alignment stage, thereby improving the adaptability of the alignment process to the terrain where the vehicle chassis is located, thereby increasing the use scenarios.

[0025] 3) The process is highly automated and intelligent, reducing the burden on drivers. The present invention uses an integrated control system to complete the calculation and generation of the aircraft's flight trajectory, data processing, attitude control, etc., which can effectively assist the driver in manipulating the aircraft. Compared with traditional mechanical or rotational adaptive matching mechanisms, it effectively reduces the burden on the driver and improves the driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG1( a ) is a schematic diagram of the initial tracking process before the aircraft and the car module are aligned based on vision and mechanical collaboration;

[0027] Figure 1(b) is a schematic diagram of the initial alignment of the aircraft and car modules based on vision and mechanical collaboration;

[0028] Figure 1(c) is a schematic diagram of the pre-alignment of the aircraft and automobile modules based on vision and mechanical collaboration;

[0029] Figure 1(d) is a schematic diagram of the final alignment of the aircraft and car modules based on vision and mechanical collaboration;

[0030] Figure 2 This is a schematic diagram of the initial alignment step where the visual module identifies and reconstructs relative positions based on feature sites;

[0031] Figure 3 It is a schematic diagram of the laser radar ranging and iterative optimization process between the modules in the pre-alignment step;

[0032] Figure 4 This is a schematic diagram of the final mating step, in which the mother-child mating area is mated based on the groove suction and the latch locking limit.

[0033] In the figure: 1-flight module, 2-ground vehicle module, 3-chassis relative space A position, 4-laser radar, 5-feature position on top of vehicle module, 6-female mating area at bottom of aircraft, 7-sub-mating area of ​​vehicle chassis, 8-slide, 9-form of vehicle after mating, 10-aircraft chassis camera, 11-feature marking point on top of vehicle module, 12-control system, 13-laser radar involved in the embodiment, 14-bottom of aircraft, 15-female mating area, 16-car chassis, 17-sub-mating area, 18-latch. DETAILED DESCRIPTION

[0034] FIG1 is a schematic diagram of the process of merging the aircraft and vehicle modules of a split flying car based on vision and mechanical collaboration. Figure 2 This is a schematic diagram of the relative spatial position identified and reconstructed by the visual module based on the chassis feature locations in the initial alignment step. Figure 3 This is a schematic diagram of the iterative optimization process between modules based on LiDAR precise ranging in the pre-alignment step. Figure 4 It is a schematic diagram of the final mating process, in which the sub-mating area and the mother-mating area are combined based on the characteristic groove suction and the latch locking limit.

[0035] like Figure 1a As shown, during the initial tracking process before the start of alignment, the control system of the flight module 1 plans the flight trajectory according to the coordinate information fed back by the ground vehicle module 2, assists the driver in controlling the flight to the sky above the predetermined location, and lowers the aircraft altitude according to the preset program until the module spacing reaches the optimal ranging range of the lidar.

[0036] After entering the initial alignment step, if Figure 1b As shown, the camera at the bottom of the aircraft identifies multiple feature markers on the top of the car module and reconstructs the relative spatial position of the chassis, which is recorded as position A 3. The integrated control system calculates the three coordinates and inclination information of the chassis plane of the car module relative to the absolute horizontal plane at this time, and controls the attitude of the flight module to adjust to the corresponding attitude with the goal of making the aircraft chassis plane and the car module chassis plane relatively parallel, and then quickly approaches position A.

[0037] Figure 1cThis is a schematic diagram of the pre-alignment steps between the aircraft and the car module. At this time, the distance between the modules is about 1 to 1.5 meters. The integrated control system instructs the laser radar 4 to start working. At the same time, based on the algorithm preset by the control system, the module alignment path and required time are automatically calculated and planned. The laser radar captures the characteristic site 5 on the top of the car module, thereby accurately measuring the module spacing in real time and providing feedback. The control system continuously iterates and optimizes based on the feedback data to complete the pre-alignment between the flight module and the ground module.

[0038] After completing the above steps, the mechanical module begins to intervene and enters the final alignment step, such as Figure 1d As shown, at this time, when the distance between the mother-child mating surface of the car module and the flight module in the docking area is 10 to 20 cm, the control system further reduces the descent rate of the flight module and approaches the preset area at a rate of 1 to 3 cm / s. When the modules are mated, the mother mating area 6 at the bottom of the aircraft slides into the child mating area 7 of the car chassis in a riveted state, and the pin in the slide groove 8 immediately locks and limits the module, and the mating is completed. The vehicle is then in the form of a car 9 on the road surface.

[0039] The object involved in this embodiment is a split-type flying vehicle for both land and air use. The vehicle is driven by a power battery. It can be a four-axis eight-propeller or a six-axis twelve-propeller according to the load requirements. The effective load of the aircraft module is not less than 200kg, and the flight range is greater than 50km. The ground vehicle chassis has a load capacity greater than 800kg. The aircraft and the chassis share a cockpit, can fly freely in the air, and can perform L2-L3 automatic driving on the ground. The aircraft and the vehicle chassis are autonomously, quickly, and accurately docked based on the above-mentioned modular docking system and docking method.

[0040] When the aircraft completes its flight mission and returns to a straight-line distance of 5 to 10 km from the ground module, the pilot issues a docking command. The flight module integrated control system then automatically plans the trajectory according to the coordinate information fed back by the ground vehicle module, assists the pilot in controlling the flight to the predetermined location, and lowers the aircraft's altitude according to the preset program until the module spacing reaches the optimal ranging range of the lidar.

[0041] Initial pairing Figure 2 As shown, the aircraft chassis camera 10 identifies the four characteristic marking points 11 on the top of the car module to reconstruct the relative spatial position. The control system 12 calculates the three coordinates and inclination information of the car chassis plane relative to the absolute horizontal plane at this time, as shown in the coordinate system, and then controls the aircraft to adjust its attitude to the corresponding attitude and approach downward at a speed of 2m / s.

[0042] After that, the involution enters the pre-involution phase ( Figure 3a), at this time, the distance between the aircraft and the car chassis is 1 meter, and the chassis laser radar 13 captures the characteristic position of the top of the car module, so as to accurately measure the module spacing in real time and feedback the results. The control system continuously iterates and optimizes based on the feedback data. The aircraft continues to move downward to the car chassis while ensuring the moving speed and trajectory accuracy. Figure 3 As shown in b~3c.

[0043] When the distance between the aircraft chassis and the top of the ground module is 15cm, the final mating stage is entered, and the control system reduces the descent rate of the flight module to 1.5cm / s. When the modules are mated, the female mating area 15 of the aircraft bottom 14 slides into the sub-mating area 17 of the vehicle chassis 16 in a riveted state, and the latch 18 in the slide groove immediately locks and limits the module, and the mating is completed.

[0044] The vehicle is then placed on the road in the form of a car.

Claims

1. A split flying car alignment method based on visual-mechanical module collaborative control, characterized in that: The following steps are involved: The method adopts a split flying car matching system, including a flight module, a vision module, a car module, a mechanical auxiliary module and an integrated control system; Step 1: During the initial tracking process, the control system of the flight module plans the flight trajectory according to the coordinate information fed back by the ground vehicle module, assists the driver in controlling the flight to the predetermined location, and lowers the aircraft altitude according to the preset program until the module spacing reaches the optimal ranging range of the lidar; Step 2: During the initial alignment process, the camera at the bottom of the flight module identifies multiple feature markers on the top of the car module and reconstructs the relative spatial position of the chassis, which is recorded as position A. The integrated control system calculates the three coordinates and inclination information of the chassis plane of the car module relative to the absolute horizontal plane at this time, and controls the flight attitude and quickly approaches position A with the goal of making the chassis plane of the aircraft and the chassis plane of the car module relatively parallel. Step 3: During the pre-alignment process, the flight module approaches position A at a relatively fast speed and gradually decelerates when the module spacing is 1 to 1.5 meters. The integrated control system automatically plans the module alignment path and required time based on a preset algorithm. At the same time, the laser radar at the bottom of the flight module accurately measures the module spacing in real time and provides feedback. The control system continuously iterates and optimizes based on the feedback data to complete the pre-alignment between the flight module and the ground module. Step 4: In the final mating process, when the distance between the parent-child mating surfaces of the docking area of ​​the car module and the flight module is 10 to 20 cm, the control system further reduces the descent rate of the flight module and approaches the preset area at a rate of 1 to 3 cm / s; when the modules are mated, the parent mating area at the bottom of the aircraft slides into the child mating area of ​​the car chassis in a riveted state, and the pins in the slide groove immediately lock and limit the module, and the mating is completed; the vehicle is subsequently in the form of a car on the road.

2. The split flying car merging method based on visual-mechanical module collaborative control as claimed in claim 1, characterized in that: The integrated control module of the split flying car docking system includes data processing and path planning algorithms, which can realize the automatic generation and evolution iteration of the trajectory within 10km between the aircraft and the car chassis. After the driver issues a docking command within the corresponding distance, the control module automatically generates the trajectory and then feeds back to the driver to assist the initial tracking process of the module docking.

3. The split flying car merging method based on visual-mechanical module collaborative control as claimed in claim 1 or 2, characterized in that: The top of the automobile module is provided with characteristic marking points at the support column position, and a plurality of characteristic marking points are mapped to the top plane of the automobile module; during the initial alignment process, the camera at the bottom of the flight module identifies the characteristic marking positions, reconstructs the relative spatial position (A) of the automobile chassis and calculates the three coordinates and inclination angle relative to the horizontal plane; the relevant coordinate information is the key reference for adjusting the posture of the automobile module.

4. The split flying car merging method based on visual-mechanical module collaborative control as claimed in claim 1 or 2, characterized in that: After the aircraft completes the attitude adjustment in the initial alignment step, the aircraft is 10 to 20 meters away from the aircraft chassis and moves toward the automobile chassis within 30 seconds at a moving speed of 1 to 2 m / s.

5. The split flying car merging method based on visual-mechanical module collaborative control as claimed in claim 3, characterized in that: After the aircraft completes the attitude adjustment in the initial alignment step, the aircraft is 10 to 20 meters away from the aircraft chassis and moves toward the automobile chassis within 30 seconds at a moving speed of 1 to 2 m / s.

6. The split flying car merging method based on visual-mechanical module collaborative control as described in claim 1, 2 or 5, characterized in that: In the third step, pre-alignment specifically refers to the alignment process when the distance between the aircraft and the car chassis is within 1.5 meters. At this time, the laser radar at the bottom of the aircraft starts to work. The laser radar collects the distance between the aircraft and the car chassis at a frame rate of 20 frames per second. The radar immediately feeds back the distance data obtained by precise ranging to the integrated control center, which adjusts and corrects the module pre-alignment process with a higher response frequency to achieve closed-loop trajectory control.

7. The split flying car merging method based on visual-mechanical module collaborative control as claimed in claim 3, characterized in that: In the third step, pre-alignment specifically refers to the alignment process when the distance between the aircraft and the car chassis is within 1.5 meters. At this time, the laser radar at the bottom of the aircraft starts to work. The laser radar collects the distance between the aircraft and the car chassis at a frame rate of 20 frames per second. The radar immediately feeds back the distance data obtained by precise ranging to the integrated control center, which adjusts and corrects the module pre-alignment process with a higher response frequency to achieve closed-loop trajectory control.

8. The split flying car merging method based on visual-mechanical module collaborative control as claimed in claim 4, characterized in that: In the third step, pre-alignment specifically refers to the alignment process when the distance between the aircraft and the car chassis is within 1.5 meters. At this time, the laser radar at the bottom of the aircraft starts to work. The laser radar collects the distance between the aircraft and the car chassis at a frame rate of 20 frames per second. The radar immediately feeds back the distance data obtained by precise ranging to the integrated control center, which adjusts and corrects the module pre-alignment process with a higher response frequency to achieve closed-loop trajectory control.

9. The split flying car merging method based on visual-mechanical module collaborative control as claimed in claim 1, characterized in that: In the fourth step, the final matching process refers to when the distance between the flight module and the car chassis is within 10 to 20 cm. At this time, the movement rate of the aircraft is controlled within 3 cm / s, and the mother matching area at the bottom of the aircraft gradually approaches the child matching area at the top of the car chassis. The module is naturally sucked in and matched in a characteristic groove matching manner. After the aircraft is in place, the pin in the slide groove is triggered to quickly lock and limit the module.

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