Ground unmanned platform cross-floor maneuvering method and device facing indoor unknown environment

Abstract

The invention provides an indoor unknown environment-oriented ground unmanned platform autonomous cross-floor maneuvering method and device. According to the method, a two-wheel differential crawler unmanned platform is adopted and is provided with a front swing arm and a rear swing arm for providing support for stair climbing; the length of the front and rear swing arms is larger than the distance between two steps. The recognition module is used for outputting stair information in real time in the maneuvering process based on laser radar information, stair modeling is conducted in the upstairs process, and the stair information is used in the downstairs process; acquiring the pose of the unmanned platform in real time by using a positioning module; the whole floor-crossing maneuver is divided into two stages of going upstairs and going downstairs, and each stage is divided into a process from the flat ground to the first step, a stable climbing process and a process from the last step to the flat ground; stair detection is carried out based on the laser radar, a three-stage cross-floor maneuvering process is matched, going upstairs and downstairs in an indoor unknown environment can be completed without a depth camera, only the stair part needs to be identified and modeled, and consumption of computing resources is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of autonomous exploration of robots / unmanned vehicles, and particularly relates to a method and device for autonomous cross-floor maneuvering of a ground unmanned platform for an indoor unknown environment. Background Art

[0002] A ground unmanned platform performing autonomous tasks in a three-dimensional space needs to cross complex three-dimensional surfaces, and the traditional two-dimensional information model is insufficient. Therefore, current environmental modeling solutions for autonomous navigation in complex buildings mostly perform a complete modeling of the entire three-dimensional environment. For example, Bouman et al. from the California Institute of Technology use a depth camera for short-range perception (Bouman A, Ginting M F, Alatur N, et al. Autonomous spot: Long-range autonomous exploration of extreme environments with legged locomotion[C] / / 2020 IEEE / RSJ International Conference on Intelligent Robots and Systems (IROS), 2020: 2518-2525.), use instantaneous lidar point clouds for medium-range perception, and use spatially fused point clouds for long-range detection, thereby constructing a local topographic map around the robot.

[0003] For a ground unmanned platform to achieve cross-floor maneuvering, it is necessary to detect and model stairs. Currently, most stair detection and modeling algorithms are based on point cloud photos taken by a depth camera. For example, Fourre et al. proposed a stair detection and localization algorithm based on the depth camera data of a tracked robot (Fourre J, Vauchey V, Dupuis Y, Savatier X. Autonomous rgbd-based industrial staircase localization from tracked robots[C] / / 2020 IEEE / RSJ International Conference on Intelligent Robots and Systems (IROS), 2020: 10691-10696.). This algorithm can be used for both ordinary stairs and industrial stairs. Their evaluation relies on the ground truth data provided by a motion capture system.

[0004] If the environment modeling scheme of autonomous navigation adopts the method of completely modeling the entire three-dimensional environment, it will cause a waste of computing resources and reduce the efficiency of data storage and reading. The present invention only recognizes and models the staircase part, which greatly reduces the consumption of computing resources.

[0005] The stair detection method based on the depth camera is restricted by the shortcomings of the depth camera itself. For example, the ground unmanned platform must adjust its yaw angle before detection to ensure that the stairs are located at the shooting angle of the depth camera for detection and modeling, which results in a large visual blind spot. The depth camera has high requirements for light. If the light intensity is too low, the accuracy of the stair detection modeling results will be low, or even the results cannot be output. This method has high requirements for the environment and is limited in its usage scenarios. The present invention uses a stair detection method based on laser radar to make up for the visual blind spot and high environmental requirements of the depth camera. Summary of the invention

[0006] In view of this, the present invention provides a method and device for autonomous cross-floor maneuvering of a ground unmanned platform in an unknown indoor environment. It performs stair detection based on a lidar and cooperates with a three-stage cross-floor maneuvering process design. It can complete going up and down stairs in an unknown indoor environment without a depth camera, and only needs to identify and model the stair part, which greatly reduces the consumption of computing resources and improves the efficiency of data storage and reading.

[0007] In order to solve the above technical problems, the present invention is implemented as follows.

[0008] A method for autonomous cross-floor maneuvering of a ground unmanned platform in an unknown indoor environment, the method adopts a two-wheel differential track unmanned platform, which has front and rear swing arms to provide support for climbing stairs; the length of the front and rear swing arms must be greater than the distance between two steps;

[0009] The entire cross-floor maneuver is divided into two stages: ascending stairs and descending stairs. Each stage is divided into the S1 process from the flat ground to the first step, the S2 process of stable climbing, and the S3 process from the last step to the flat ground.

[0010] The recognition module is used to output stair information in real time during the maneuver based on the laser radar information, stair modeling is performed during the upstairs process, and it is used when going downstairs; the positioning module is used to obtain the position and posture of the unmanned platform in real time;

[0011] In the S1 process, the stair model is used to locate the initial position of the movement, the forearm and the steps are used to interact to change the posture of the unmanned platform, and the crawler tracks are combined to make the unmanned platform parallel to the inclined surface of the stairs;

[0012] In the S2 process, according to the stair information and the posture of the unmanned platform, the posture is adjusted so that the unmanned platform remains parallel to the inclined surface of the stairs during the climbing process until it reaches the last step;

[0013] During the S3 process, the attitude of the unmanned platform is changed by the interaction between the forearm and the steps, and it moves forward with the crawlers. When the unmanned platform is in front of the last step, the support between the swing arm and the stairs is withdrawn by rotating the swing arm, and the unmanned platform falls to the ground under the action of gravity.

[0014] Preferably, the S1 process of climbing the stairs is specifically as follows:

[0015] First, the climbing stairs are identified by the recognition module and the stairs are modeled to obtain the position information at the midpoint of the first step and the direction information of the stairs; then enter the S1 process, control the unmanned platform to move to a point that is offset by a set distance in the opposite direction of the climbing direction from the midpoint of the first step, achieving the attitude in the climbing direction, and the angles of the front and rear swing arms are both perpendicular to the ground direction;

[0016] Then, control the front swing arm to swing downward to raise the front part of the crawlers of the unmanned platform to the height of the first step, and then control the unmanned platform to move forward; after the positioning module outputs that the front wheel position of the unmanned platform is above the first step, adjust the angles of the front and rear swing arms to ensure that the front swing arm does not touch the step and the rear swing arm contacts the ground; control the unmanned platform to continue moving forward. When the positioning module outputs that the center of gravity position of the unmanned platform is above the first step, it is considered that it has completely climbed the stairs, the S1 process of climbing the stairs ends and the S2 process of climbing the stairs is entered.

[0017] Preferably, the S2 process of climbing the stairs is specifically as follows:

[0018] Adjust the yaw angular velocity of the unmanned platform in real time according to the yaw angle information output by the positioning module to ensure going straight during the climbing process; control the angles of the front and rear swing arms in real time according to the pitch angle information output by the positioning module to ensure that the unmanned platform is parallel to the inclined surface of the stairs during the climbing process;

[0019] When the center of gravity height information of the unmanned platform output by the positioning module is consistent with the stair height information output by the recognition module, it is considered that the last step has been reached, the S2 of climbing the stairs ends and the S3 process of climbing the stairs is entered.

[0020] Preferably, the S3 process of climbing the stairs is specifically as follows:

[0021] Control the front swing arm to swing downward to provide support for the unmanned platform to fall to the ground; then control the unmanned platform to move forward; when the center of gravity of the unmanned platform exceeds the last step, control the front swing arm to swing upward to gradually withdraw the support, and the unmanned platform on the ground falls to the flat ground under the action of gravity until it is completely in contact with the ground; the S3 process of climbing the stairs ends and the climbing of the stairs is completed.

[0022] Preferably, the S1 process of going down the stairs is specifically as follows:

[0023] Based on the centroid position information output by the positioning module and the midpoint position of the last step in the stair model established when going upstairs, determine whether the unmanned platform enters the stair area; after entering the stair area, enter the S1 process;

[0024] Control the unmanned platform to move to a point that is offset by a set distance in the opposite direction of the downward stair direction along the midpoint of the step and face the downward stair direction; then control the front swing arm to swing downward to provide support for the unmanned platform to land on the stairs; then control the unmanned platform to move forward; the unmanned platform lands on the stairs under the action of gravity, and the S1 process of going downstairs ends and enters the S2 process of going downstairs.

[0025] Preferably, the S2 process of going downstairs is specifically as follows:

[0026] According to the yaw angle information output by the positioning module, adjust the yaw angular velocity of the unmanned platform in real time to ensure going straight during the climbing process; according to the pitch angle information output by the positioning module, control the angles of the front and rear swing arms in real time to ensure being parallel to the stair inclined plane during the climbing process; the unmanned platform relies on the self-locking function of the crawler to prevent it from sliding down;

[0027] When the centroid height information of the unmanned platform output by the positioning module is consistent with the height information of the first step in the stair model established when going upstairs, it is considered that the last step has been reached; the S2 process of going downstairs ends and enters the S3 process of going downstairs.

[0028] Preferably, the S3 process of going downstairs is specifically as follows:

[0029] Control the front swing arm to swing upward and control the crawler to move forward; when the position output by the positioning module is in front of the last step, control the front and rear swing arms to swing upward to avoid contacting the ground and the step, and the unmanned platform lands on the flat ground under the action of gravity; the S3 process of going downstairs ends and the downstairs process is completed.

[0030] The present invention also provides a ground unmanned platform autonomous cross-floor maneuvering device for an indoor unknown environment. The device uses a two-wheel differential crawler unmanned platform, which has front and rear swing arms to provide support for climbing stairs; the lengths of the front and rear swing arms need to be greater than the straight-line distance between the edges of two steps; an identification module, a positioning module, and a path planning and control module are installed on the unmanned platform;

[0031] The identification module is based on lidar information and outputs stair information in real time during the maneuvering process; stair modeling is carried out during the upstairs process and used during the downstairs process;

[0032] The positioning module obtains the pose of the unmanned platform in real time;

[0033] The path planning and control module controls the cross-floor maneuvering process: The entire cross-floor maneuvering is divided into two stages: going up the stairs and going down the stairs. Each stage is further divided into an S1 process from flat ground to the first step, an S2 process of stable climbing, and an S3 process from the last step to flat ground.

[0034] In the S1 process, the initial movement position is located using the stair model, the attitude of the unmanned platform is changed by the interaction between the forearm and the step, and the crawler is combined to move forward, so that the unmanned platform reaches a posture parallel to the inclined plane of the stairs.

[0035] In the S2 process, according to the stair information and the pose of the unmanned platform, the pose is adjusted so that the unmanned platform maintains a parallel posture with the inclined plane of the stairs during the climbing process until it reaches the last step.

[0036] In the S3 process, the attitude of the unmanned platform is changed by the interaction between the forearm and the step, and the crawler is combined to move forward. When the unmanned platform is in front of the last step, the support between the swing arm and the stairs is withdrawn by rotating the swing arm, and the unmanned platform falls to the ground under the action of gravity.

[0037] Preferably, the positioning module uses lidar point cloud information and inertial measurement unit information for positioning.

[0038] Advantages:

[0039] (1) In an unknown environment without prior map information, relying only on the lidar point cloud information and the positioning signal of the inertial measurement unit, the vehicle self-positioning and stair detection modeling can be completed simultaneously, and the cross-floor trajectory planning can be completed according to the positioning signal and stair information. There is no need to use a depth camera, so the light requirement for the scene is not high, and high-precision stair detection modeling and up-and-down stair control can be realized in various scenarios.

[0040] (2) The present invention does not need to completely model the entire three-dimensional environment, only needs to identify and model the stair part, which greatly reduces the consumption of computing resources and improves the data storage and reading efficiency.

[0041] (3) The present invention divides the entire cross-floor maneuvering process into two stages: going up the stairs and going down the stairs, and each stage is further divided into a process from flat ground to the first step, a stable climbing process, and a process from the stairs to flat ground. In each process, the pose that the ground unmanned platform should reach and the angle that the swing arm should reach are analyzed in detail, which improves the attitude control ability and accurately completes the maneuvering of each stage. Description of the Drawings

[0042] Figure 1 It is a module composition diagram of the autonomous cross-floor maneuvering method for a ground unmanned platform facing an indoor unknown environment;

[0043] Figure 2Schematic diagram of the process from flat ground to the first step during the up - stair stage;

[0044] Figure 3 Schematic diagram of the stable climbing process during the up - stair stage;

[0045] Figure 4 Schematic diagram of the process from the stairs to flat ground during the up - stair stage;

[0046] Figure 5 Schematic diagram of the process from flat ground to the first step during the down - stair stage;

[0047] Figure 6 Schematic diagram of the stable descending process during the down - stair stage;

[0048] Figure 7 Schematic diagram of the process from the stairs to flat ground during the down - stair stage. Detailed implementation manners

[0049] The present invention will be described in detail below with reference to the accompanying drawings and by way of examples.

[0050] In the present invention, a two - wheel differential tracked mobile platform is used. Two tracks provide power to enable the movement of the unmanned platform. The front and rear swing arms are used as auxiliary means to provide support for the ground unmanned platform to climb stairs. The angle range of the front and rear swing arms needs to reach - 180° to 180°, and the swing arm angle needs to be accurate to 1°. The length of the front and rear swing arms needs to be greater than the distance between two steps, and this distance is the straight - line distance between the edges of adjacent two steps. In one embodiment, there are 2 front and rear swing arms respectively, a total of four swing arms, so as to facilitate stable postures. In practice, a structure with more swing arms can also be adopted. If there is one front and one rear swing arm, it will increase the difficulty of attitude control.

[0051] Figure 1 The figure shows a schematic diagram of a ground unmanned platform autonomous cross - floor maneuvering device provided by the present invention. This maneuvering device uses the above - mentioned mobile platform and is equipped with an identification module, a positioning module, and a planning and control module.

[0052] The identification module uses a lidar to realize the identification and modeling of stairs. The positioning module uses a tightly - coupled LIO (a system combining lidar and inertial measurement unit) to realize the self - vehicle pose estimation. The planning and control module controls the cross - floor maneuvering process. It divides the entire cross - floor maneuvering process into two stages: up - stair and down - stair, and each stage is further divided into a process from flat ground to the first step (S1), a stable climbing process (S2), and a process from the stairs to flat ground (S3). According to the data of the identification module and the positioning module, in each process, it controls the position and attitude of the ground unmanned platform to move autonomously, as well as the angle reached by the swing arms.

[0053] In the S1 process, the stair model is used to locate the initial position of the movement, the forearm and the steps are used to interact to change the posture of the unmanned platform, and the crawler tracks are combined to make the unmanned platform parallel to the inclined surface of the stairs;

[0054] In the S2 process, according to the stair information and the posture of the unmanned platform, the posture is adjusted so that the unmanned platform remains parallel to the inclined surface of the stairs during the climbing process until it reaches the last step;

[0055] In the S3 process, the posture of the unmanned platform is changed by the interaction between the forearm and the steps, and the unmanned platform moves forward in combination with the tracks. When the unmanned platform is in front of the last step, the swing arm is rotated to cancel the support of the swing arm and the stairs, and the unmanned platform falls to the ground under the action of gravity.

[0056] The three processes of going up and down stairs are described in detail below with reference to the accompanying drawings.

[0057] 1) Stair climbing stage

[0058] The specific process of stair climbing S1 stage is as follows:

[0059] First, the recognition module identifies the stairs and models the stairs, and then obtains the position information of the midpoint of the first step and the direction information of the stairs. Then, the process of going from the flat ground to the first step is started. The control module controls the ground unmanned platform to move to the midpoint of the first step and the point offset by a set distance in the opposite direction of the stairs. The posture to be achieved is facing the direction of the stairs. It is preferred to control the front and rear swing arm angles to be perpendicular to the ground to avoid collision with the stairs and affect movement. Figure 2 Then, the regulation and control module controls the front swing arm to swing downward, and preferably, the rear swing arm can keep the position unchanged, as shown in FIG. Figure 2 The downward swing of the front swing arm will contact the step surface, thereby raising the front part of the crawler of the ground unmanned platform to the height of the first step. Then the control module controls the crawler of the ground unmanned platform to work and move forward, as shown in Figure (b). Figure 2 When the positioning module outputs that the front wheel position of the ground unmanned platform is above the first step, the front and rear swing arms are adjusted to ensure that the front swing arm does not hit the step and the rear swing arm is in contact with the ground, as shown in (c). Figure 2 The control module controls the ground unmanned platform to continue moving forward. When the positioning module outputs that the center of gravity of the ground unmanned platform is above the first step, it is considered that it has completely climbed the stairs, as shown in (d). Figure 2 The first process ends and enters the stable climbing process S2.

[0060] The specific process of stair climbing S2 stage is as follows:

[0061] First, the control module adjusts the yaw angular velocity of the ground unmanned platform in real time according to the yaw angle information output by the positioning module to ensure that it can walk in a straight line during the climbing process; and controls the front and rear swing arm angles in real time according to the pitch angle information output by the positioning module to ensure that it can remain parallel to the inclined surface of the stairs during the climbing process. Figure 3 When the center of gravity height information of the ground unmanned platform output by the positioning module is consistent with the stair height information output by the recognition module, it is considered that it has reached the last step. The second process ends and enters the process from stairs to flat ground S3.

[0062] The specific process of stair climbing S3 stage is as follows:

[0063] In the process of going from the stairs to the flat ground, the regulation and control module controls the front swing arm to swing downward to provide support for the unmanned platform to land on the ground, and slowly lift the unmanned platform. Figure 4 Then the control module controls its forward movement, as shown in (a). Figure 4 When the center of gravity of the unmanned platform exceeds the last step, the front swing arm is controlled to swing upward to gradually remove the support, and the ground unmanned platform falls to the flat ground under the action of gravity until it is completely in contact with the ground. Figure 4 As shown in (c), the stair climbing process S3 ends and the stair climbing is completed.

[0064] 2) Stair descent

[0065] The specific process of the S1 stage of going down the stairs is as follows:

[0066] In this stage, the stair model established when going upstairs is still used. If the center of gravity position information output by the positioning module is near the midpoint of the last step in the stair model established when going upstairs, it is judged that the ground unmanned platform has entered the stair area. Then, it enters the process S1 from the flat ground to the first step. The regulation and control module controls the ground unmanned platform to move to the point in the middle of the step that is offset by a set distance in the opposite direction of the downstairs. The posture to be achieved is facing the downstairs direction, and the swing arm angle remains unchanged.

[0067] Then, the regulation and control module controls the front swing arm to swing downward to provide support for the unmanned platform on the ground to land on the stairs. Figure 5 Then the ground unmanned platform is controlled to move forward. The ground unmanned platform falls onto the stairs under the action of gravity, as shown in (a). Figure 5 The first process S1 ends and enters the stable climbing process S2.

[0068] The specific process of the S2 stage of going down the stairs is as follows:

[0069] During the stable climbing process, the path planning and control module adjusts the yaw angular velocity of the ground unmanned platform in real time according to the yaw angle information output by the positioning module to ensure that it can move in a straight line during climbing; and controls the angles of the front and rear swing arms in real time according to the pitch angle information output by the positioning module to ensure that it can remain parallel to the inclined surface of the stairs during climbing, as Figure 6 shown.

[0070] During this process, the ground unmanned platform relies on the self-locking function of the crawlers to prevent it from sliding down, and relies on the front and rear swing arms to ensure a stable climbing process.

[0071] When the height information output by the positioning module is consistent with the height information of the first step in the stair model established during going upstairs, it is considered that it has reached the last step. The second process S2 ends and enters the process S3 from the stairs to the flat ground.

[0072] The specific process of the going-downstairs S3 stage is as follows:

[0073] The path planning and control module controls the front swing arm to swing upward, and then the path planning and control module controls it to move forward, as Figure 7 shown in (a). When the center-of-gravity position output by the positioning module is in front of the last step, the path planning and control module controls the rear swing arm to swing upward, and the ground unmanned platform falls onto the flat ground under the action of gravity, as Figure 7 shown in (b). The third process S3 ends and the going-downstairs is completed.

[0074] The above specific embodiments only describe the design principle of the present invention. The shapes and names of the components in this description can be different and are not limited. Therefore, those skilled in the art of the present invention can modify or make equivalent replacements to the technical solutions recorded in the foregoing embodiments; and these modifications and replacements do not depart from the spirit and technical solutions of the present invention and should all fall within the protection scope of the present invention.

Claims

1. A method for autonomous cross-floor maneuvering of a ground unmanned platform in an unknown indoor environment, characterized in that: This method uses a two-wheel differential crawler unmanned platform, which has front and rear swing arms to provide support for climbing stairs; the length of the front and rear swing arms must be greater than the distance between two steps; The entire cross-floor maneuver is divided into two stages: ascending stairs and descending stairs. Each stage is divided into the S1 process from the flat ground to the first step, the S2 process of stable climbing, and the S3 process from the last step to the flat ground. The recognition module is used to output stair information in real time during the maneuver based on the laser radar information, stair modeling is performed during the upstairs process, and it is used when going downstairs; the positioning module is used to obtain the position and posture of the unmanned platform in real time; In the S1 process, the stair model is used to locate the initial position of the movement, the forearm and the steps are used to interact to change the posture of the unmanned platform, and the crawler tracks are combined to make the unmanned platform parallel to the inclined surface of the stairs; In the S2 process, according to the stair information and the posture of the unmanned platform, the posture is adjusted so that the unmanned platform remains parallel to the inclined surface of the stairs during the climbing process until it reaches the last step; In the S3 process, the posture of the unmanned platform is changed by the interaction between the forearm and the steps, and the unmanned platform moves forward in combination with the tracks. When the unmanned platform is in front of the last step, the swing arm is rotated to cancel the support of the swing arm and the stairs, and the unmanned platform falls to the ground under the action of gravity.

2. The method according to claim 1, characterized in that The S1 process of climbing stairs is as follows: First, the recognition module identifies the stairs and models the stairs to obtain the position information of the midpoint of the first step and the direction information of the stairs; then enters the S1 process to control the unmanned platform to move to the midpoint of the first step and the point offset by a set distance in the opposite direction of the stairs to achieve a posture facing the direction of the stairs, and the front and rear swing arm angles are both perpendicular to the ground; Then, the front swing arm is controlled to swing downward to raise the front part of the crawler track of the unmanned platform to the height of the first step, and then the unmanned platform is controlled to move forward; when the positioning module outputs that the front wheel position of the unmanned platform is above the first step, the angles of the front and rear swing arms are adjusted to ensure that the front swing arm does not hit the step and the rear swing arm is in contact with the ground; the unmanned platform is controlled to continue moving forward, and when the positioning module outputs that the center of gravity of the unmanned platform is above the first step, it is considered that it has completely climbed the stairs, and the stair climbing S1 process ends and enters the stair climbing S2 process.

3. The method according to claim 1, characterized in that The S2 process of going up the stairs is as follows: According to the yaw angle information output by the positioning module, the yaw angular velocity of the unmanned platform is adjusted in real time to ensure that it moves in a straight line during the climbing process; according to the pitch angle information output by the positioning module, the front and rear swing arm angles are controlled in real time to ensure that the unmanned platform remains parallel to the inclined surface of the stairs during the climbing process; When the center of gravity height information of the unmanned platform output by the positioning module is consistent with the stair height information output by the recognition module, it is considered that the last step has been reached, the stair climbing S2 is completed and the stair climbing S3 process is entered.

4. The method according to claim 1, characterized in that The S3 process of going up the stairs is as follows: The front swing arm is controlled to swing downward to provide support for the unmanned platform to land on the ground; then the unmanned platform is controlled to move forward; when the center of gravity of the unmanned platform exceeds the last step, the front swing arm is controlled to swing upward to gradually withdraw the support, and the ground unmanned platform falls to the flat ground under the action of gravity until it is completely in contact with the ground; the stair climbing S3 process ends and the stair climbing is completed.

5. The method according to claim 1, characterized in that The S1 process of going down the stairs is as follows: According to the center of gravity position information output by the positioning module and the midpoint position of the last step in the stair model established when going upstairs, it is determined whether the unmanned platform has entered the stair area; after entering the stair area, it enters the S1 process; The unmanned platform is controlled to move to the midpoint of the step and to a point offset by a set distance in the opposite direction of the stairs, and faces the direction of the stairs; then the front swing arm is controlled to swing downward to provide support for the unmanned platform to fall on the stairs; then the unmanned platform is controlled to move forward; the unmanned platform falls on the stairs under the action of gravity, and the downstairs S1 process ends and enters the downstairs S2 process.

6. The method according to claim 1, characterized in that The S2 process of going down the stairs is as follows: The yaw angle information output by the positioning module is used to adjust the yaw angular velocity of the unmanned platform in real time to ensure that it moves in a straight line during climbing. The pitch angle information output by the positioning module is used to control the front and rear swing arm angles in real time to ensure that it is parallel to the inclined surface of the stairs during climbing. The unmanned platform relies on the self-locking function of the crawler to prevent it from sliding down. When the center of gravity height information of the unmanned platform output by the positioning module is consistent with the height information of the first step in the stair model established when going upstairs, it is considered that the last step has been reached; the downstairs S2 process ends and enters the downstairs S3 process.

7. The method according to claim 1, characterized in that The S3 process of going down the stairs is as follows: The front swing arm is controlled to swing upward and the crawler track is controlled to move forward. When the position output by the positioning module is in front of the last step, the front and rear swing arms are controlled to swing upward to avoid contact with the ground and the steps. The unmanned platform falls to the flat ground under the action of gravity. The stair descent S3 process ends and the stair descent is completed.

8. An autonomous cross-floor maneuvering device for an unmanned ground platform in an unknown indoor environment, characterized in that: The device uses a two-wheel differential crawler unmanned platform, which has front and rear swing arms to provide support for climbing stairs; the length of the front and rear swing arms must be greater than the straight-line distance between the corners of two steps; the unmanned platform is equipped with an identification module, a positioning module and a regulation and control module; The recognition module outputs stair information in real time during the maneuver based on the LiDAR information; stair modeling is performed during the ascent process and used when descending the stairs; The positioning module obtains the position and posture of the unmanned platform in real time; The regulation and control module controls the cross-floor maneuvering process: the entire cross-floor maneuvering is divided into two stages: ascending stairs and descending stairs. Each stage is divided into the S1 process from the flat ground to the first step, the S2 process of stable climbing, and the S3 process from the last step to the flat ground. In the S1 process, the stair model is used to locate the initial position of the movement, the forearm and the steps are used to interact to change the posture of the unmanned platform, and the crawler tracks are combined to make the unmanned platform parallel to the inclined surface of the stairs; In the S2 process, according to the stair information and the posture of the unmanned platform, the posture is adjusted so that the unmanned platform remains parallel to the inclined surface of the stairs during the climbing process until it reaches the last step; In the S3 process, the posture of the unmanned platform is changed by the interaction between the forearm and the steps, and the unmanned platform moves forward in combination with the tracks. When the unmanned platform is in front of the last step, the swing arm is rotated to cancel the support of the swing arm and the stairs, and the unmanned platform falls to the ground under the action of gravity.

9. The device according to claim 8, characterized in that The positioning module uses laser radar point cloud information and inertial measurement unit information for positioning.

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