Method and device for controlling unmanned vehicle to climb stairs, unmanned vehicle and readable storage medium

Abstract

The application provides a step climbing control method and device for an unmanned vehicle, the unmanned vehicle and a readable storage medium, and relates to the technical field of unmanned vehicle control. The method comprises the following steps: when it is determined that the front is a step, the front wheel connecting rod leg and the rear wheel connecting rod leg are respectively controlled to swing in a clockwise direction to a balance mode through a first steering engine and a second steering engine; based on the balance mode, the front wheel connecting rod leg is controlled to swing in an anticlockwise direction to the front wheel being placed on the step through the first steering engine; based on the state of the front wheel being placed on the step, the rear wheel connecting rod leg is controlled to swing in an anticlockwise direction to a backward straightening state through the second steering engine, and the unmanned vehicle is controlled to move forward to climb the step through a motor. According to the embodiment of the application, the swing angles of the front wheel connecting rod leg and the rear wheel connecting rod leg are respectively controlled through the first steering engine and the second steering engine, the mode of the unmanned vehicle is controlled to be changed, the probability that the wheels are stuck and slide can be reduced when a higher step is encountered, and the step can be successfully climbed.

Description

Technical Field

[0001] This application relates to the field of unmanned vehicle control technology, and in particular to an unmanned vehicle stair climbing control method, device, unmanned vehicle, and readable storage medium. Background Technology

[0002] With the continuous development of technology, unmanned vehicles are being used more and more widely. Various complex working environments are placing higher and higher demands on the control of unmanned vehicles. For example, common working scenarios include climbing stairs.

[0003] Currently, when encountering steps, autonomous vehicles are usually accelerated to a certain initial velocity and used inertia to climb the steps. However, this method is mostly applicable to scenarios where the steps are relatively low. For scenarios where the steps are high (e.g., the height of the steps exceeds the radius of the wheels), the wheels of the autonomous vehicle will still be blocked by the steps and keep slipping, preventing the autonomous vehicle from climbing the steps smoothly. Summary of the Invention

[0004] According to various embodiments of this application, a method, apparatus, unmanned vehicle and readable storage medium for controlling unmanned vehicle climbing stairs are provided, which can solve the problem that the wheels are blocked by the stairs and keep slipping, causing the unmanned vehicle to be unable to climb the stairs smoothly.

[0005] In a first aspect, this application provides a method for controlling an unmanned vehicle to climb stairs, applied to an unmanned vehicle, the unmanned vehicle including front wheels, rear wheels, and a first servo motor controlling the angle of the front wheel linkage leg and a second servo motor controlling the angle of the rear wheel linkage leg respectively; the method includes: when it is determined that there is a stair in front, controlling the front wheel linkage leg and the rear wheel linkage leg to swing clockwise to a balance mode by the first servo motor and the second servo motor respectively; based on the balance mode, controlling the front wheel linkage leg to swing counterclockwise to the front wheel resting on the stair; based on the state of the front wheel resting on the stair, controlling the rear wheel linkage leg to swing counterclockwise to a straightened state by the second servo motor, and controlling the unmanned vehicle to move forward and climb the stair by a motor.

[0006] In this way, the unmanned vehicle controls the swing angle of the front wheel linkage leg and the rear wheel linkage leg respectively through the first and second servo motors. This allows the unmanned vehicle to change its mode from a normal crawling mode to a balanced mode. In the balanced mode, the front wheels can climb onto the step, and then the crawling mode when the front wheels are on the step is switched to a straightened rear wheel linkage leg. This reduces the probability of the wheels getting stuck and slipping when encountering higher steps. As the unmanned vehicle moves forward, the rear wheels can also climb onto the step smoothly after the front wheels have climbed it. This method has strong ease of use and practicality.

[0007] In one possible implementation of the first aspect, controlling the front wheel link leg and the rear wheel link leg to swing clockwise to a balanced mode via the first servo and the second servo respectively includes:

[0008] Based on the crawling mode of the unmanned vehicle, the second servo motor controls the rear wheel linkage leg to swing clockwise by a first preset angle to a high position mode;

[0009] Based on the high-position mode, the first servo motor controls the front wheel linkage leg to swing clockwise by a second preset angle to the balance mode.

[0010] In one possible implementation of the first aspect, the step of controlling the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step, based on the balance mode, via the first servo, includes:

[0011] Based on the balance mode, the first servo motor controls the front wheel linkage leg to swing counterclockwise by a third preset angle, so that the front wheel rests on the step;

[0012] Accordingly, controlling the rear wheel linkage leg to swing counterclockwise to a straight rearward position via the second servo motor includes:

[0013] The second servo motor controls the rear wheel link leg to swing counterclockwise by a fourth preset angle, so that the rear wheel link leg is in a straightened rearward state.

[0014] In one possible implementation of the first aspect, the step of controlling the front wheel linkage leg to swing clockwise by a second preset angle to the balance mode via the first servo motor, based on the high-position mode, includes:

[0015] Based on the high-position mode, the front wheel linkage leg is controlled by the first servo motor to swing clockwise by the second preset angle until the front wheel is lifted, and the rear wheel supports the balance mode; in the balance mode, the height of the front wheel after being lifted is higher than the height of the step.

[0016] In one possible implementation of the first aspect, the method further includes:

[0017] When the front wheels are lifted, the unmanned vehicle is controlled to be in the balance mode by means of the rear wheels, based on the vehicle's posture and the rear wheel speed.

[0018] In one possible implementation of the first aspect, after controlling the front wheel link leg and the rear wheel link leg to swing clockwise to a balanced mode via the first servo and the second servo respectively, the method further includes:

[0019] Based on the balance mode, the unmanned vehicle is controlled to move forward to the target position, which is the position where the front wheels of the unmanned vehicle can step onto the step when they swing counterclockwise.

[0020] In one possible implementation of the first aspect, the step of controlling the unmanned vehicle to move forward and climb the steps via a motor includes:

[0021] The front and rear wheels are driven forward by motors on the front and rear wheels respectively, allowing the unmanned vehicle to climb the steps.

[0022] Secondly, this application provides an unmanned vehicle stair-climbing control device, applied to an unmanned vehicle, the unmanned vehicle including front wheels, rear wheels, and a first servo motor controlling the angle of the front wheel linkage leg and a second servo motor controlling the angle of the rear wheel linkage leg respectively; the device includes:

[0023] The first control unit is used to control the front wheel link leg and the rear wheel link leg to swing clockwise to a balance mode when it is determined that there is a step in front of it;

[0024] The second control unit is used to control the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step, based on the balance mode, via the first servo motor.

[0025] The third control unit is used to control the rear wheel linkage leg to swing counterclockwise to a straight rearward position via the second servo motor, based on the state of the front wheel resting on the step, and to control the unmanned vehicle to move forward and climb the step via the motor.

[0026] Thirdly, this application provides an unmanned vehicle, the unmanned vehicle including front wheels, rear wheels, at least one processor, and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the method described in any one of the first aspects.

[0027] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in any one of the first aspects.

[0028] Fifthly, this application provides a computer program product that, when run on a server, causes the server to perform the method described in any one of the first aspects above.

[0029] It is understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 A schematic diagram of the architecture of an unmanned vehicle provided in an embodiment of this application;

[0032] Figure 2 A flowchart illustrating the unmanned vehicle stair climbing control method provided in this application embodiment;

[0033] Figure 3 A schematic diagram of the state transition of an unmanned vehicle executing a first step-climbing strategy, provided in an embodiment of this application.

[0034] Figure 4 A schematic diagram illustrating the front wheels of an unmanned vehicle mounting a step, provided in an embodiment of this application;

[0035] Figure 5 A schematic diagram illustrating the state of an unmanned vehicle executing a second step-climbing strategy, provided in an embodiment of this application.

[0036] Figure 6 A schematic diagram illustrating the force distribution on the rear wheels of an unmanned vehicle provided in an embodiment of this application;

[0037] Figure 7 A schematic diagram of the rear swing angle of the rear wheel linkage leg of an unmanned vehicle provided in an embodiment of this application;

[0038] Figure 8 A schematic diagram of the overall process of the unmanned vehicle stair climbing control method provided in the embodiments of this application;

[0039] Figure 9 This is a schematic diagram of the structure of the unmanned vehicle stair climbing control device provided in the embodiments of this application;

[0040] Figure 10 A structural schematic diagram of an unmanned vehicle is provided for an embodiment of this application. Detailed Implementation

[0041] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0043] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0044] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0045] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0046] Currently, autonomous vehicle designs include two-wheeled or four-wheeled transformable vehicles, which, compared to ordinary autonomous vehicles, have joint servos that can control the overall shape of the vehicle. When faced with low steps, the autonomous vehicle can accelerate to a certain initial speed and use its inertia to climb the step. However, when encountering higher steps (e.g., steps whose height is greater than the wheel radius), the wheels will be blocked by the step, causing them to slip and preventing them from using inertia to climb the step.

[0047] This application proposes a method for controlling an unmanned vehicle to climb stairs to address the above-mentioned problems. By controlling the unmanned vehicle to change its form and switching between different forms, both the front and rear wheels can smoothly climb the stairs, thereby solving the problem of the unmanned vehicle's wheels slipping due to being blocked by higher stairs.

[0048] The architecture of this driverless car will be introduced first below.

[0049] Please see Figure 1 , Figure 1This is a schematic diagram of the architecture of the unmanned vehicle provided in the embodiments of this application, such as... Figure 1 Figure (a) shows a frontal side view of the unmanned vehicle. The vehicle includes a body, front wheels, rear wheels, a first servo motor, a second servo motor, front wheel linkages, and rear wheel linkages. The first servo motor connects the body to the front wheel linkages and controls their angular position by providing a certain amount of rotational torque. The second servo motor connects the body to the rear wheel linkages and controls their angular position by providing a certain amount of rotational torque. The unmanned vehicle also has built-in gyroscopes and accelerometers to detect the vehicle's attitude information. Additionally, the unmanned vehicle includes motors that individually control the speed of each wheel.

[0050] For example, the driverless vehicle can be a two-wheeled or four-wheeled variant, such as a vehicle with only two wheels, front and rear, or a front wheel with two synchronized wheels and a rear wheel with two synchronized wheels.

[0051] Taking a four-wheeled transforming vehicle as an example, such as Figure 1 As shown in Figure (b), the first servo motor may include servo motor 1 and servo motor 4, which control the swing angle of the two front wheel linkage legs respectively; the second servo motor may include servo motor 2 and servo motor 3, which control the swing angle of the two rear wheel linkage legs respectively. The front wheels may include front wheels 5 and 8, and the rear wheels may include rear wheels 6 and 7. Servo motors 1 to servo motor 4 control the swing angle of the four linkage legs respectively, and the speed of the four wheels is controlled by four corresponding motors. The two front wheels are located on both sides of the vehicle body, and the two rear wheels are located on both sides of the vehicle body.

[0052] Based on the aforementioned autonomous vehicle architecture, motion control involves balancing the rear wheels to allow the front wheels to lift and climb the steps. Simultaneously, as the front wheels touch the steps, the rear wheel linkage lifts backward to near-horizontal, and a motor drives the rear wheels forward, enabling them to smoothly climb the steps. Specifically, motion control can include: using a first servo to control the rear wheels to touch the ground and balance when the front wheels lift; moving forward (towards the steps) with the rear wheels balanced to a position where the front wheels can touch the steps; using the first servo to control the front wheels to lower and touch the steps (returning to the normal crawling state); using a second servo to control the rear wheel linkage to lift backward to near-horizontal; and using a motor to drive the wheels forward, returning to the normal crawling state after climbing the steps.

[0053] In this embodiment of the application, through the above control process, the front wheels are placed on the step in the balance mode, and then the crawling mode when the front wheels are placed on the step is converted to the rear wheel linkage leg swinging backward. This reduces the probability of the wheels getting stuck and slipping when encountering higher steps. Through the drive of the unmanned vehicle moving forward, the rear wheels can also successfully climb the step after the front wheels have climbed it.

[0054] The specific implementation process of the unmanned vehicle stair climbing control method is described below through a specific embodiment.

[0055] Please see Figure 2 , Figure 2 This is a schematic diagram illustrating the implementation flow of the unmanned vehicle stair climbing control method provided in an embodiment of this application. The executing entity of this method can be... Figure 1 The unmanned vehicle in the context can include front wheels, rear wheels, and a first servo motor that controls the angle of the front wheel linkage leg, and a second servo motor that controls the angle of the rear wheel linkage leg; such as Figure 2 As shown, the method may include the following steps:

[0056] S201, when it is determined that there is a step in front, the first servo motor and the second servo motor respectively control the front wheel link leg and the rear wheel link leg to swing clockwise to the balance mode.

[0057] In this embodiment of the application, the unmanned vehicle may include a first step-climbing strategy for the front wheels to climb the step. The first step-climbing strategy includes the process of the unmanned vehicle changing its form from crawling mode to balancing mode.

[0058] For example, an autonomous vehicle can detect the presence of steps ahead using visual sensors or radar, or determine the presence of a high step if it cannot move forward by accelerating. The first and second servos control the front and rear wheel linkages to swing clockwise, changing the vehicle's shape and reaching a balanced angular position.

[0059] S202, based on the balance mode, controls the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step via the first servo motor.

[0060] For example, the unmanned vehicle is controlled by the first and second servo motors to switch from the normal crawling mode to the balance mode when the front wheels are lifted; in the balance mode, driven by the rear wheel motor, it moves towards the step until the front wheels can rest on the step, for example, the distance to the step is measured by radar or vision sensors and is less than the length of the front wheel linkage leg; and based on the balance mode, the first servo motor controls the front wheel linkage leg to swing counterclockwise, so that the front wheels rest on the step, thus completing the strategy of the front wheels going up the step.

[0061] Among them, such as Figure 3 As shown in Figure (a), the crawling mode of an autonomous vehicle in its normal state is characterized by all tires in contact with the ground, the front wheels in front of the vehicle, the rear wheels behind the vehicle, and the vehicle remaining level. Figure 3As shown in Figure (c), the balance mode when the front wheels are raised and the rear wheels rotate clockwise by a preset angle in crawling mode to maintain the overall balance of the autonomous vehicle, with the front of the vehicle higher than the rear, is the balance mode when the front wheels are raised. By raising the front wheel linkage leg to climb the steps, the problem of the wheels getting stuck due to the steps being too high can be avoided. Through the transformation of the autonomous vehicle's shape, the front wheels can climb the steps smoothly.

[0062] In some embodiments, controlling the front wheel link leg and the rear wheel link leg to swing clockwise to a balanced mode via a first servo motor and a second servo motor respectively includes:

[0063] Based on the crawling mode of the unmanned vehicle, the second servo motor controls the rear wheel linkage leg to swing clockwise by a first preset angle to the high position mode; based on the high position mode, the first servo motor controls the front wheel linkage leg to swing clockwise by a second preset angle to the balance mode.

[0064] For example, such as Figure 3 The diagram illustrates the specific form change process of the autonomous vehicle when executing the first step-climbing strategy. From crawling mode, the vehicle uses a first servo motor to control the swing angle of the front wheel linkage leg, and a second servo motor to control the swing angle of the rear wheel linkage leg. This causes the vehicle's wheels to change position while in contact with the ground, raising the center of gravity and shifting it forward. The rear wheels tilt towards the front wheels, placing the vehicle in a high position (front low, rear high), i.e., the autonomous vehicle in its high-position mode. Figure 3 The shape shown in Figure (b) is as follows.

[0065] In some embodiments, based on the high-position mode, controlling the front wheel linkage leg to swing clockwise by a second preset angle to the balance mode via a first servo motor includes:

[0066] Based on the high-position mode, the front wheel linkage leg is controlled by the first servo motor to swing clockwise by a second preset angle until the front wheel is lifted, and the rear wheel supports it in the balance mode; in the balance mode, the height of the front wheel after it is lifted is higher than the height of the step.

[0067] For example, after the autonomous vehicle switches from crawling mode to high-position mode, the first servo motor controls the angle of the front wheel linkage leg to raise it to a position where the front wheel is higher than the step height. At the same time, the rear wheels support the vehicle body and maintain the vehicle body balance, so that the autonomous vehicle is in a balanced mode.

[0068] For example, such as Figure 3 As shown in Figure (b), the high-position mode is the transitional form for the unmanned vehicle to switch from crawling mode to balanced mode. The angle of the rear wheel linkage leg is changed by the second servo motor. For example, the inner angle of the rear wheel linkage leg gradually swings forward (clockwise) from 45° in crawling mode to 110° (swinging 65°), which is the high-position mode.

[0069] In one possible implementation, during the transition from crawling mode to high-position mode, the rotation of the second servo motor simultaneously lifts the front of the vehicle body upwards, changing the vehicle position required for the rear wheel balance mode. For example, while the rear wheel linkage leg swings forward, the first servo motor can simultaneously control the front wheel linkage leg to swing from an inner angle of 45° in crawling mode to 65° (i.e., rotate counterclockwise by 20° or make the inner angle greater than 45°), causing the autonomous vehicle's center of gravity to be too high and lean forward, and the rear wheels to tilt forward, thus placing the autonomous vehicle in a high-position mode. Here, the aforementioned inner angle can be the angle between the linkage leg and the horizontal direction.

[0070] For example, when the autonomous vehicle is in the high-position mode, a first servo motor provides rotational torque, controlling the front wheel linkage leg to swing clockwise, i.e., lift upwards. Supported by the rear wheels, this maintains the autonomous vehicle's balance, placing it in a balanced mode. Figure 3 As shown in Figure (c), in balance mode, the height of the front wheel after it is lifted can be higher than the height of the step.

[0071] In some embodiments, the method further includes: when the front wheels are lifted, controlling the autonomous vehicle to be in a balance mode based on the vehicle's attitude and the rear wheel speed by supporting the rear wheels.

[0072] For example, when the front wheels are lifted and the rear wheels are supported, the autonomous vehicle is controlled to be in a balanced mode by using a proportional-derivative-integral (PID) algorithm based on the vehicle's posture and the speed of the rear wheels.

[0073] Among them, in such Figure 3 The crawling mode shown in Figure (a) and the switching to such Figure 3 In the high-position mode shown in Figure (b), the PID algorithm is not required to control vehicle balance; it is only activated in balance mode when the front wheels are lifted. Vehicle attitude includes the vehicle's pitch angle, and rear wheel speed includes forward and backward speeds.

[0074] For example, the process of controlling vehicle balance using a PID algorithm can be calculated based on the error between the actual measured pitch angle of the vehicle body and the preset pitch angle of the balanced state. For instance, it can be calculated using the following formula:

[0075]

[0076] Where error(t) is the pitch angle error that changes over time, and cmd(t) is a parameter used to control the rear wheel speed. The pitch angle error is used to control the wheel speed to achieve balance. The actual pitch angle can be measured based on the accelerometer and gyroscope. Based on the balance control, the front wheel is lifted up.

[0077] In one possible implementation, when the autonomous vehicle switches from high-position mode to balanced mode, it may be far from the step. In this case, the rear-wheel motor drives the vehicle to move towards the step in balanced mode until the front wheels can land on the step without the rear wheels hitting it. That is, the autonomous vehicle is controlled to move forward to the target position based on balanced mode. The target position is the position where the front wheels can reach the step when the vehicle swings counter-clockwise. Figure 4 As shown in Figure (a), the specific distance detection and target position determination in front of the steps can be based on radar or visual sensors.

[0078] In some embodiments, based on a balance mode, controlling the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step via a first servo motor includes:

[0079] Based on the balance mode, the front wheel linkage leg is controlled by the first servo motor to swing counterclockwise by a third preset angle, so that the front wheel rests on the step.

[0080] For example, in such Figure 4 In the balance mode shown in Figure (a), the first servo motor controls the swing angle of the front wheel linkage leg, causing the front wheel linkage leg to rotate counterclockwise, and the front wheel lands on the step, as shown in Figure (a). Figure 4 As shown in Figure (b) of the document.

[0081] For example, when the autonomous vehicle is moved to a position where the front wheels can land on the step by the rear wheel motor, the PID algorithm can be turned off. The first servo motor controls the front wheel linkage leg to swing downwards, and the rear wheel linkage leg to swing backwards. Simultaneously, the second servo motor controls the rear wheel linkage leg to swing backwards, while the rear wheel motor drives the rear wheel to accelerate backwards for a short time, ensuring that the front wheels are on the step (or the vehicle body is placed forward on the step), so that the entire autonomous vehicle is in a crawling mode, lying on the step.

[0082] S203, based on the state of the front wheels resting on the steps, controls the rear wheel linkage leg to swing counterclockwise to a straight position through the second servo motor, and controls the unmanned vehicle to move forward and climb the steps through the motor.

[0083] In this embodiment, the autonomous vehicle may further include a second step-climbing strategy for the rear wheels during the step-climbing process. This second strategy involves the autonomous vehicle switching from a front-wheel-on-step-step crawling mode to a rear-wheel linkage leg swinging counter-clockwise until it is fully extended. Based on the front-wheel-on-step state, the autonomous vehicle uses a second servo motor to adjust the angle of the rear-wheel linkage leg, causing it to swing backward to a state nearly parallel to the vehicle body. This changes the angle between the rear-wheel linkage leg and the ground, allowing the rear wheels to touch the ground while simultaneously raising the contact point with the step. This makes it easier for the autonomous vehicle to climb the step under motor drive.

[0084] For example, driverless cars can be manufactured by, for instance, Figure 4 As shown in Figure (b), proceed forward to the state as described in Figure (b). Figure 5 The state shown in Figure (a) is the rear wheel against the step. Then, the second servo controls the rear wheel linkage leg to swing backward to the position shown in Figure (a). Figure 5 The state is shown in Figure (b). Based on the front wheels being on the step, the motors of both the front and rear wheels simultaneously drive the autonomous vehicle forward, causing the rear wheels to be carried onto the step.

[0085] In some embodiments, controlling the rear wheel linkage leg to swing counterclockwise to a straight rearward position via the second servo motor includes:

[0086] The second servo motor controls the rear wheel link leg to swing counterclockwise by a fourth preset angle, so that the rear wheel link leg is in a straightened rearward state.

[0087] The fourth preset angle is used to bring the rear wheels onto the step when the driverless car is moving forward.

[0088] For example, before the rear wheels of the autonomous vehicle go up the step, the vehicle's center of gravity needs to be raised, but Figure 5 As shown in Figure (a), the rear wheels did not swing backward to a near-horizontal position. The rear of the autonomous vehicle was already quite high, and the front wheels were already against the step. The upward movement of the center of gravity meant that the upward friction from the step was insufficient for the rear wheels, causing them to continuously slip on the ground. Figure 5 As shown in Figure (b), the rear wheel linkage leg extends to near horizontal position. At this time, the rear of the vehicle body is in a low position, and when the wheel moves forward, the rear of the vehicle body is more likely to rise to a position sufficient to allow the rear wheel to get onto the step when the rear wheel linkage leg hits the step.

[0089] like Figure 6 As shown, the center of gravity O of the unmanned vehicle, the center of the front wheel A, and the center of the rear wheel B are considered as a rigid link AOB, with the mass of the unmanned vehicle located at the center O of the vehicle body. Since the height of the step may be greater than or equal to the wheel radius, the elastic force exerted by the step on the wheel points horizontally to the right from the contact point to the center of the circle. As the wheel rotates forward, a vertically upward frictional force is generated between the wheel and the step. The resultant force in the vertical direction is assumed to be f. If the center of gravity needs to be lifted upwards, the entire rigid link AOB is rotated counterclockwise, with the front wheel A as the rotation point. Since the component of the rotational force is fcosθ, it is clear that the component of the rotational force is larger in the straightened state, i.e., the rotational force is greater. Figure 6 The angle θ shown in Figure (a) is greater than Figure 6 The angle θ is shown in Figure (b); where, Figure 6 Figure (a) shows the state when the rear wheel has not swung backward to near horizontal. Figure 6 Figure (b) shows the state when the rear wheel swings backward to near horizontal.

[0090] For example, such as Figure 7 As shown, the angle between the line connecting the center of gravity O and the center of the servo and the straight line of the vehicle body is set to α (unchanged). When the control command from the second servo gives the rear wheel linkage leg a backward swing angle of α (i.e., α = β), the straight-line distance between the center of gravity and the rear wheel is at its maximum, the lever arm is at its longest, and the torque is at its maximum, i.e., the rotational force is at its maximum, making it easier for the rear wheel to climb the step. Specifically, when the servo angle control β is 10 degrees and 45 degrees, the difference in the lever arm controlling the rear wheel is very small. The second servo can control the rear wheel linkage leg to swing backward to a position with an angle of 10° or 45° to the horizontal.

[0091] In some embodiments, controlling an unmanned vehicle to move forward and climb stairs by means of motors includes: driving the front wheels and the rear wheels forward by means of motors on the front wheels and the rear wheels, respectively, so that the unmanned vehicle can climb stairs.

[0092] For example, after controlling the second servo to swing the rear wheel linkage leg backward to near full extension, the second servo remains stationary, controlling the motors of the front and rear wheels to rotate forward, thereby allowing the rear wheel to climb the step. By extending the rear wheel linkage leg backward to near horizontal, the probability of being blocked by the step can be reduced, while allowing the rear wheel to climb the step using the friction of the step's edge.

[0093] Correspondingly, after controlling the rear wheels to climb the steps, the unmanned vehicle returns to the normal crawling mode, that is, the rear wheel linkage leg is controlled to swing to the normal mode by the second servo motor.

[0094] Through the embodiments of this application, the unmanned vehicle executes a first step-climbing strategy and a second step-climbing strategy, enabling the unmanned vehicle to change its form from a normal crawling mode to a balanced mode. In the balanced mode, the front wheels are placed on the step, and then the crawling mode when the front wheels are on the step is converted to a rear wheel linkage leg that is swung backward. This reduces the probability of the wheels getting stuck and slipping when encountering higher steps. With the unmanned vehicle moving forward, the rear wheels can also successfully climb the step after the front wheels have climbed it. For unmanned vehicles with few degrees of freedom, low torque, and the ability to change form, the method provided by the embodiments of this application effectively solves the problem of wheels being unable to climb steps due to slippage when stuck.

[0095] like Figure 8 As shown in the figure, this application embodiment also provides an overall flowchart of the unmanned vehicle climbing stair control method. Based on the same implementation principle as the above embodiment, it will not be repeated here. The overall process may include the following steps:

[0096] S81, preparing to enter high-level mode.

[0097] S82 controls the front wheels to lift while the rear wheels provide support and balance.

[0098] S83, move forward.

[0099] S84: Is it near the edge of the step? If yes, then execute S85; otherwise, then execute S83.

[0100] S85, control the front wheels to lower and mount the step.

[0101] S86 controls the rear wheel linkage to achieve a straight rearward swing.

[0102] S87 controls the motors of the front and rear wheels to drive forward simultaneously, causing the rear wheels to be carried up the step.

[0103] S88, switch to normal crawling mode.

[0104] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0105] Corresponding to the unmanned vehicle climbing stairs method provided in the above embodiment, Figure 9 A schematic diagram of the unmanned vehicle stair-climbing device provided in the embodiments of this application is shown. For ease of explanation, only the parts related to the embodiments of this application are shown.

[0106] Reference Figure 9 The device includes:

[0107] The first control unit 91 is used to control the front wheel link leg and the rear wheel link leg to swing clockwise to a balance mode when it is determined that there is a step in front of it;

[0108] The second control unit 92 is used to control the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step, based on the balance mode, via the first servo motor.

[0109] The third control unit 93 is used to control the rear wheel linkage leg to swing counterclockwise to a straight rearward position via the second servo motor based on the state of the front wheel resting on the step, and to control the unmanned vehicle to move forward and climb the step via the motor.

[0110] In one possible implementation, the first control unit 91 is further configured to, based on the crawling mode of the unmanned vehicle, control the rear wheel linkage leg to swing clockwise by a first preset angle to a high position mode via the second servo motor; and based on the high position mode, control the front wheel linkage leg to swing clockwise by a second preset angle to the balance mode via the first servo motor.

[0111] In one possible implementation, the second control unit 92 is further configured to control the front wheel link leg to swing counterclockwise by a third preset angle via the first servo motor based on the balance mode, so that the front wheel rests on the step; the third control unit 93 is further configured to control the rear wheel link leg to swing counterclockwise by a fourth preset angle via the second servo motor, so that the rear wheel link leg is in a backward straightened state.

[0112] In one possible implementation, the first control unit 91 is further configured to, based on the high-position mode, control the front wheel linkage leg to swing clockwise by a first servo motor to a second preset angle until the front wheel is lifted, and to be in the balance mode by the rear wheel support; the height of the front wheel after being lifted in the balance mode is higher than the height of the step.

[0113] In one possible implementation, the first control unit 91 is further configured to control the unmanned vehicle to be in the balance mode based on the vehicle posture and rear wheel speed, by means of the rear wheel support, when the front wheels are lifted.

[0114] In one possible implementation, the second control unit 92 is further configured to control the unmanned vehicle to move forward to a target position based on the balance mode, the target position being a position where the front wheels of the unmanned vehicle can step onto a step when they swing counterclockwise.

[0115] In one possible implementation, the third control unit 93 is also used to drive the front wheel and the rear wheel forward by means of the motors of the front wheel and the rear wheel, respectively, so that the unmanned vehicle can climb the steps.

[0116] Through the embodiments of this application, the unmanned vehicle executes a first step-climbing strategy and a second step-climbing strategy, enabling the unmanned vehicle to change its form from a normal crawling mode to a balanced mode. In the balanced mode, the front wheels are placed on the step, and then the crawling mode when the front wheels are on the step is converted to a rear wheel linkage leg that is straightened backward. This reduces the probability of the wheels getting stuck and slipping when encountering higher steps. With the propulsion of the unmanned vehicle moving forward, the rear wheels can also successfully climb the step after the front wheels have climbed it.

[0117] Figure 10 A schematic diagram of the hardware structure of the unmanned vehicle 10 is shown.

[0118] like Figure 10 As shown, the unmanned vehicle 10 in this embodiment includes: at least one processor 100 ( Figure 10 (Only one is shown in the image), memory 101, front wheel 103, and rear wheel 104. Memory 101 stores a computer program 102 that can run on the processor 100. When the processor 100 executes the computer program 102, it implements the steps in the above method embodiments, for example... Figure 2 S201 to S203 are shown. Alternatively, when the processor 100 executes the computer program 102, it implements the functions of each module / unit in the above-described device embodiments.

[0119] It is understood that the structures illustrated in the embodiments of this application do not constitute a specific limitation on the unmanned vehicle 10. In other embodiments of this application, the unmanned vehicle 10 may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0120] The unmanned vehicle 10 may include, but is not limited to, a processor 100 and a memory 101. Those skilled in the art will understand that... Figure 10 This is merely an example of the driverless car 10 and does not constitute a limitation on the driverless car 10. It may include more or fewer components than shown, or combine certain components, or different components. For example, the server may also include input sending devices, network access devices, buses, etc.

[0121] The processor 100 mentioned above can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor.

[0122] The processor 100 may also include a memory for storing instructions and data. In some embodiments, the memory in the processor 100 is a cache memory. This memory can store instructions or data that the processor 100 has just used or that are used repeatedly. If the processor 100 needs to use the instruction or data again, it can retrieve it directly from the memory. This avoids repeated accesses, reduces the waiting time of the processor 100, and thus improves the efficiency of the system.

[0123] In some embodiments, the aforementioned memory 101 may be an internal storage unit of the autonomous vehicle 10, such as a hard drive or memory of the autonomous vehicle 10. The memory 101 may also be an external storage device of the autonomous vehicle 10, such as a plug-in hard drive, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the autonomous vehicle 10. Furthermore, the memory 101 may include both internal and external storage units of the autonomous vehicle 10. The memory 101 is used to store operating systems, applications, bootloaders, data, and other programs, such as program code for computer programs. The memory 101 can also be used to temporarily store data that has been sent or will be sent.

[0124] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0125] It should be noted that the above server structure is only illustrative. Depending on the application scenario, other entity structures may also be included. No limitation is made on the entity structure of the server here.

[0126] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0127] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps described in the various method embodiments above.

[0128] This application provides a computer program product that, when run on a server, enables the server to execute the steps described in the various method embodiments above.

[0129] If the integrated modules / units are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0130] The apparatus, unmanned vehicle, computer storage medium, and computer program product provided in the embodiments of this application are all used to execute the methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects corresponding to the methods provided above, and will not be repeated here.

[0131] It should be understood that the above description is merely to help those skilled in the art better understand the embodiments of this application, and is not intended to limit the scope of the embodiments of this application. Based on the examples given above, those skilled in the art can obviously make various equivalent modifications or changes. For example, some steps in the various embodiments of the above detection method may be unnecessary, or new steps may be added. Alternatively, any combination of two or more of the above embodiments may be used. Such modifications, changes, or combinations also fall within the scope of the embodiments of this application.

[0132] It should also be understood that the methods, situations, categories, and classifications of embodiments in this application are for the convenience of description only and should not constitute a special limitation. Various methods, categories, situations, and features in embodiments can be combined without contradiction.

[0133] It should also be understood that, in the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0134] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0135] In the embodiments provided in this application, it should be understood that the disclosed apparatus / network devices and methods can be implemented in other ways. For example, the apparatus / network device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0136] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0137] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

[0138] Finally, it should be noted that the above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for controlling an unmanned vehicle to climb stairs, characterized in that, The method is applied to an unmanned vehicle, which includes front wheels, rear wheels, and a first servo motor that controls the angle of the front wheel linkage leg and a second servo motor that controls the angle of the rear wheel linkage leg; the method includes: When it is determined that there is a step in front, the first servo motor and the second servo motor respectively control the front wheel link leg and the rear wheel link leg to swing clockwise to the balance mode; Based on the balance mode, the first servo motor controls the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step; Based on the state of the front wheel resting on the step, the second servo motor controls the rear wheel linkage leg to swing counterclockwise until it is straightened backward, and the motor controls the unmanned vehicle to move forward and climb the step.

2. The method according to claim 1, characterized in that, The step of controlling the front wheel link leg and the rear wheel link leg to swing clockwise to a balanced mode via the first servo and the second servo respectively includes: Based on the crawling mode of the unmanned vehicle, the second servo motor controls the rear wheel linkage leg to swing clockwise by a first preset angle to a high position mode; Based on the high-position mode, the first servo motor controls the front wheel linkage leg to swing clockwise by a second preset angle to the balance mode.

3. The method according to claim 1, characterized in that, Based on the balance mode, controlling the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step via the first servo motor includes: Based on the balance mode, the first servo motor controls the front wheel linkage leg to swing counterclockwise by a third preset angle, so that the front wheel rests on the step; Accordingly, controlling the rear wheel linkage leg to swing counterclockwise to a straight rearward position via the second servo motor includes: The second servo motor controls the rear wheel link leg to swing counterclockwise by a fourth preset angle, so that the rear wheel link leg is in a straightened rearward state.

4. The method according to claim 2, characterized in that, Based on the high-position mode, controlling the front wheel linkage leg to swing clockwise by a second preset angle to the balance mode via the first servo motor includes: Based on the high-position mode, the front wheel linkage leg is controlled by the first servo motor to swing clockwise by the second preset angle until the front wheel is lifted, and the rear wheel supports the balance mode; in the balance mode, the height of the front wheel after being lifted is higher than the height of the step.

5. The method according to claim 4, characterized in that, The method further includes: When the front wheels are lifted, the unmanned vehicle is controlled to be in the balance mode by means of the rear wheels, based on the vehicle's posture and the rear wheel speed.

6. The method according to claim 1, characterized in that, After controlling the front wheel link leg and the rear wheel link leg to swing clockwise to a balanced mode via the first servo and the second servo respectively, the method further includes: Based on the balance mode, the unmanned vehicle is controlled to move forward to the target position, which is the position where the front wheels of the unmanned vehicle can step onto the step when they swing counterclockwise.

7. The method according to any one of claims 1 to 6, characterized in that, The step of controlling the unmanned vehicle to move forward and climb the steps by means of a motor includes: The front and rear wheels are driven forward by motors on the front and rear wheels respectively, allowing the unmanned vehicle to climb the steps.

8. A stair-climbing control device for an unmanned vehicle, characterized in that, The device is applied to an unmanned vehicle, which includes front wheels, rear wheels, and a first servo motor that controls the angle of the front wheel linkage leg and a second servo motor that controls the angle of the rear wheel linkage leg; the device includes: The first control unit is used to control the front wheel link leg and the rear wheel link leg to swing clockwise to a balance mode when it is determined that there is a step in front of it; The second control unit is used to control the front wheel linkage leg to swing counterclockwise until the front wheel rests on the step, based on the balance mode, via the first servo motor. The third control unit is used to control the rear wheel linkage leg to swing counterclockwise to a straight rearward position via the second servo motor, based on the state of the front wheel resting on the step, and to control the unmanned vehicle to move forward and climb the step via the motor.

9. An unmanned vehicle, characterized in that, The unmanned vehicle includes front wheels, rear wheels, at least one processor, and a memory communicatively connected to the at least one processor; The memory stores a computer program that is executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 7.

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