Method, apparatus, device, and storage medium for determining a target point of a mobile device

Abstract

An embodiment of the present invention discloses a method, device, equipment, and storage medium for determining a target point of a mobile device. The method includes: obtaining the position point, speed information, and acceleration information of the mobile device, and determining the target point closest to the position point according to the position point, the speed information, and the acceleration information, so as to control the mobile device to move based on the target point. This solution improves the moving efficiency of the mobile device, reduces unnecessary travel consumption, and the process of determining the target point does not depend on external conditions.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of route planning, and in particular, to a method, apparatus, device, and storage medium for determining a target point of a mobile device. Background Art

[0002] With the development of mobile device technology, its application scenarios are increasing, and the functions it performs are also rich and diverse. For example, in the implementation of smart agriculture, operations performed by drones or ground devices can significantly improve operation efficiency and operation effects. During the movement of a mobile device, how to quickly and accurately determine the target point to achieve smooth and efficient movement of the mobile device is an important problem that needs to be solved currently.

[0003] In the related art, taking the return of a mobile device as an example, when the mobile device receives a return instruction, it constructs a flight map based on its collected own position and image information, and then returns along the original route based on this flight map, or controls the mobile device to hover, and plans the return route after hovering. In the above methods, the method based on image information depends on the image sensor, and special weather such as rain, fog, and sand and dust will cause it to be unavailable or increase the return time. For the method of controlling the mobile device to hover and then plan the return route, it will further increase the return time and increase the power consumption of the mobile device. Summary of the Invention

[0004] The embodiments of the present invention provide a method, apparatus, device, and storage medium for determining a target point of a mobile device, which solve the problem of unreasonable selection of the target point of the mobile device in the related art, improve the movement efficiency of the mobile device, and reduce unnecessary distance consumption.

[0005] In a first aspect, the embodiments of the present invention provide a method for determining a target point of a mobile device, the method including:

[0006] Obtain the position point, speed information, and acceleration information of the mobile device;

[0007] Determine the target point closest to the position point according to the position point, the speed information, and the acceleration information, so as to control the mobile device to move based on the target point.

[0008] In a second aspect, the embodiments of the present invention further provide a device for determining a target point of a mobile device, the device including:

[0009] An information acquisition module configured to obtain the position point, speed information, and acceleration information of the mobile device;

[0010] A target point calculation module, configured to determine a target point closest to the position point according to the position point, the velocity information, and the acceleration information, for controlling the mobile device to move based on the target point.

[0011] In a third aspect, an embodiment of the present invention further provides a mobile device target point determination device, which includes:

[0012] One or more processors;

[0013] A storage device for storing one or more programs,

[0014] When the one or more programs are executed by the one or more processors, the one or more processors implement the mobile device target point determination method described in the embodiments of the present invention.

[0015] In a fourth aspect, an embodiment of the present invention further provides a storage medium storing computer-executable instructions, and the computer-executable instructions are used to execute the mobile device target point determination method described in the embodiments of the present invention when executed by a computer processor.

[0016] In the embodiments of the present invention, by obtaining the position point, velocity information, and acceleration information of the mobile device, a target point closest to the position point is determined according to the position point, the velocity information, and the acceleration information, for controlling the mobile device to move based on the target point. This solution improves the movement efficiency of the mobile device, reduces unnecessary distance consumption, and the process of determining the target point does not depend on external conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a flowchart of a mobile device target point determination method provided by an embodiment of the present invention;

[0018] Figure 2 It is a flowchart of a method for determining a target point based on a position point, velocity information, and acceleration information provided by an embodiment of the present invention;

[0019] Figure 3 It is a flowchart of a mobile device target point determination method provided by an embodiment of the present invention;

[0020] Figure 4 It is a flowchart of a method for optimizing a target point provided by an embodiment of the present invention;

[0021] Figure 5 It is a flowchart of a method for planning a return flight trajectory based on a return point provided by an embodiment of the present invention;

[0022] Figure 5a It is a schematic diagram of a generated return flight trajectory provided by an embodiment of the present invention;

[0023] Figure 6 A schematic diagram of the movement trajectory of an exemplary mobile device provided by an embodiment of the present invention;

[0024] Figure 7 A module schematic diagram of a mobile device target point determination device provided by an embodiment of the present invention;

[0025] Figure 8 A structural schematic diagram of a mobile device target point determination device provided by an embodiment of the present invention. Detailed implementation manners

[0026] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0027] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are usually of the same category, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally indicates an "or" relationship between the associated objects before and after.

[0028] Next, in conjunction with the accompanying drawings, the mobile device target point determination method provided by the embodiments of the present application will be described in detail through specific embodiments and their application scenarios.

[0029] Figure 1 A flowchart of a mobile device target point determination method provided by an embodiment of the present invention. This embodiment can achieve short-term and efficient movement of the mobile device. This method can be executed by the mobile device control unit, and specifically includes the following steps:

[0030] Step S101, obtain the position point, speed information, and acceleration information of the mobile device.

[0031] In one embodiment, during the movement of the mobile device, its position point, speed information, and acceleration information are acquired. Among them, the position point represents the current position of the mobile device, which can be an actual geographical location or a virtual position, and the speed information and acceleration information characterize the current speed and acceleration of the mobile device. Optionally, the position point, speed information, and acceleration information can be obtained through on-board sensors of the mobile device, such as an inertial measurement unit and a positioning sensor, or can be sensed through a vision system integrated inside the mobile device. The mobile device can include, but is not limited to, a plant protection drone, a mapping drone, an unmanned vehicle, and an unmanned ship.

[0032] In one embodiment, during the movement of the mobile device, the position point, speed information, and acceleration information of the mobile device are acquired every preset time, where the preset time can be 100 milliseconds. That is, the current position point, speed information, and acceleration information of the mobile device are acquired every 100 milliseconds for calculating the target point.

[0033] Step S102: Determine the target point closest to the position point according to the position point, the speed information, and the acceleration information.

[0034] In one embodiment, after acquiring the position point, speed information, and acceleration information of the mobile device, the target point closest to the current position point is calculated based on the position point, speed information, and acceleration information. Optionally, taking the example that the mobile device needs to return during the navigation along the target route, the target point can be the determined return point, and the determined target point closest to the current position point can be the return point closest to the position point determined on the target route based on the position point, speed information, and acceleration information. The target route is a pre-planned safe navigation route of the mobile device, such as a safe operation route of the mobile device in the farmland area obtained by processing through an optimal planning algorithm.

[0035] Optionally, the method for determining the target point closest to the position point based on the acquired position point, speed information, and acceleration information can be the target point closest to the position point determined along the target route based on the trapezoidal speed distribution algorithm. The trapezoidal speed distribution algorithm is a method for trajectory planning based on a piecewise function, which consists of three sections of functions: acceleration, constant speed, and deceleration. Of course, the above three types of piecewise functions will be deleted and processed according to the actual navigation situation.

[0036] Figure 2 The flowchart of a method for determining a target point based on a position point, speed information, and acceleration information provided by an embodiment of the present invention is as Figure 2 shown, and specifically includes:

[0037] Step S1021: Calculate the speed decay time required for the mobile device to decelerate to 0 when performing speed decay control with the maximum acceleration according to the speed information.

[0038] Exemplarily, this speed decay time is denoted as t stop , the speed of the mobile device is denoted as v(k), and the maximum acceleration is denoted as a max , then It represents the time required for the mobile device to decelerate from the current speed to 0.

[0039] Step S1022: Calculate the acceleration decay time required for the mobile device to decelerate the acceleration to 0 when performing acceleration decay control with the maximum jerk according to the acceleration information.

[0040] Exemplarily, this acceleration decay time is denoted as t dcc , the acceleration of the mobile device is denoted as a(k), and the maximum jerk is denoted as j max . Then calculate t dcc During the process of calculating t, if the included angle between the velocity and acceleration vectors of the current mobile device is less than 90°, it means that the mobile device is in an accelerating process. At this time, If the included angle between the velocity and acceleration vectors of the current drone is greater than 90°, it means that the drone is in a decelerating process. At this time, t dcc = 0.

[0041] Step S1023: Add the speed decay time and the acceleration decay time to obtain the hover control time required for the mobile device to be in a hover state.

[0042] In one embodiment, after calculating the speed decay time and the acceleration decay time, the sum of the two is used as the hover control time required for the mobile device to be in a hover state. This hover control time is denoted as t0, then t0 = t dcc + t stop .

[0043] Step S1024: Calculate the target point closest to the position point according to the hover control time and the position point.

[0044] Exemplarily, the current target flight path of the mobile device is denoted as r(t), the current moment is denoted as k, and the position point p(k) at this moment k is denoted as [x(k), y(k), z(k)] T , where x(k), y(k), z(k) are the coordinates representing the current position point. The target point on the target flight path estimated by the shortest distance algorithm is denoted as r1, corresponding to the moment k1, and this k1 = k + t0. Correspondingly, the position point coordinates of the r1 point are denoted as [r x (k + t0), r y(k + t0), r z (k + t0)] T 。

[0045] After obtaining the above target points, the operation of the mobile device can be controlled based on the target points according to the actual motion scenario, where the actual motion scenario includes but is not limited to: return flight scenario, terrain-following flight scenario, route switching scenario, scenario where the height of some parts of the route needs to be vertically increased, such as crossing high obstacles, and hovering scenario. The application of the target points in the above scenarios will be described below:

[0046] In the return flight scenario, the target point can be used as the return point, which is used as a transition point for the mobile device to return from the current position to the starting point. When the mobile device needs to return, it can quickly find the target point closest to the current position and perform the return operation at the target point.

[0047] In the terrain-following flight scenario, the target point can be used as a transition point between the first working point and the second working point with a height difference greater than the set height value, so that the mobile device can quickly reach the second working point from the first working point through the transition point, without the need for the mobile device to hover and rise to the corresponding height at the previous working point and then continue to fly to the next working point as in the related art when the height difference between two working points is greater than the set height value to ensure the safe operation of the mobile device. When the height of the next position point is lower, the drone generally hovers above the next position point and then descends to the corresponding height before continuing to operate. Therefore, there must be a pause. Therefore, in the embodiment of the present invention, by using the above solution, a safe target point is first generated between the first working point and the second working point, and then the mobile device is controlled to run from the first working point through the target point to the second working point, thereby ensuring that the mobile device can continuously run from the first working point with a large height difference to the second working point during the terrain-following flight process, which is beneficial to improving the flight smoothness and operation efficiency.

[0048] In the scenario where the height of some parts of the route needs to be vertically increased, such as when crossing wires or other high obstacles, the target point can be used as a transition point during the obstacle avoidance process of the mobile device for high obstacles, so that the mobile device can safely and smoothly cross the high obstacles from the current position through the target point. The horizontal and vertical coordinates of the target point can be the same as those of the original route or can be adaptively adjusted, but generally the height information will be changed, and the height information can be increased or decreased to avoid high obstacles. This can solve the pause caused by hovering first and then avoiding obstacles when the mobile device encounters high obstacles in the related art.

[0049] In the flight path switching scenario, the target point can serve as the flight path switching point when the mobile device switches flight paths, and is used as a transition point during the process of the mobile device smoothly switching from the current position to the new flight path. After the mobile device is controlled to move from the current position to the target point, it continues to move from the target point to the starting point of the new flight path, so as to smoothly switch the mobile device from the current position to the new flight path to continue the operation.

[0050] In the hovering scenario, the target point can serve as the safe hovering end point after the mobile device avoids obstacles, or can also serve as the safe hovering end point for the mobile device to perform hovering operations after receiving a hovering instruction. By using the target point as the safe hovering end point to control the mobile device to hover when moving from the current position to the target point, it is possible to avoid the problem that a large shake of the mobile device caused by rapid hovering affects the service life of the mobile device.

[0051] It should be noted that the target points in the above scenarios can all be determined through the above steps S1021 to S1024 provided by the present invention. When generating the trajectory from the position point to the target point, the corresponding trajectory constraints are followed to ensure that when the determined target point moves from the position point to this point, the mobile device can achieve smooth, continuous and non-rapid speed changes. When the target point is used as a transition point, the path adopted by the mobile device when continuing to move forward from the target point to the next position point, such as the starting point or the second working point, can be planned by using the path optimization algorithm in the related technology, but it is not limited thereto.

[0052] As can be seen from the above, this solution can determine the target point in real time by obtaining the position point, speed information and acceleration information of the mobile device, and determining the target point closest to the position point according to the position point, speed information and acceleration information, so as to timely meet the flight requirements of the mobile device in the above various scenarios that it may face. Moreover, it does not require external dependence conditions, nor does it need to first control the mobile device to hover and then perform route planning, which greatly reduces the movement time and movement distance, and thus improves the flight efficiency of the mobile device.

[0053] In some scenarios where the mobile device is suspended, for example, the mobile device is suspended due to obstacle avoidance or receiving user instructions, such as when a drone is hovering for a period of time, because it is in a non-operating state, if the target point determined last time is continued to be used to control the operation of the mobile device, the target point may not be applicable to the operation requirements of the current mobile device, for example, it may cause the mobile device to collide with an obstacle during the process of continuing to operate according to the target point. Therefore, in order to ensure whether the target point is applicable to the mobile control of the current mobile device to ensure the safe operation of the mobile device, in one embodiment, before controlling the mobile device to move based on the target point, the method may also include the following steps: based on the current time information of the mobile device and the determination time information of the target point determined last time, determine whether the target point is available; if it is determined that the target point is available, control the mobile device to move based on the target point; if it is determined that the target point is not available, redetermine the target point based on the current position point, velocity information and acceleration information of the mobile device, and control the mobile device to move based on the redetermined target point. Among them, the process of redetermining the target point can be exemplarily: r2=p(k)+0.5*v(k)*(t dcc +t stop ), where r2 is the updated target point, p(k) is the current position of the mobile device, v(k) is the current speed of the mobile device, and t dcc is the acceleration decay time, t stop is the velocity decay time, where t dcc and t stop The calculation method of is referred to the above exemplary description and will not be repeated here.

[0054] In the above, when the difference between the current time information and the determined time information is less than the preset interval threshold, it is determined that the target point determined last time is available; otherwise, it is determined that the target point determined last time is unavailable.

[0055] Based on the embodiment of determining whether the target point is available, the following takes the target point as the return point as an example to illustrate another method for determining the target point of a mobile device provided by an embodiment of the present invention. Figure 3 As shown, Figure 3 The flowchart of a method for determining a target point of a mobile device provided by an embodiment of the present invention. It should be noted that the aforementioned description of the target point may also be a transition point in other scenarios, a safe hovering end point, etc., and similarly, it may also include a method for determining whether it is available, an optimization process, and a subsequent method for generating a smooth trajectory based on the transition point, the operation end point, etc. The following is an exemplary description using the return point as an example, and the other explanations are not repeated. Figure 3 The examples shown specifically include:

[0056] Step S201: Obtain the position points, speed information, and acceleration information of the mobile device.

[0057] Step S202: Determine the return point closest to the position point based on the position point, the speed information, and the acceleration information.

[0058] In one embodiment, the position points, speed information, and acceleration information of the mobile device can be obtained every preset time, such as 100 milliseconds described in the foregoing exemplary description, and the return point can be calculated accordingly, and the determination time information of obtaining this return point can be recorded accordingly. Exemplarily, taking the current moment as the 0th second, when calculating the return point closest to the position point based on the current position point, speed information, and acceleration information of the mobile device through the trapezoidal speed distribution algorithm, the corresponding time span can be exemplarily 2 to 3 seconds, where this time span can be the hovering control time calculated above. Of course, the above takes the trapezoidal speed distribution algorithm as an example to calculate the return point, and other distribution algorithms can also be used to calculate the return point closest to the position point.

[0059] Step S203: When receiving the return instruction of the mobile device, obtain the current moment information.

[0060] In one embodiment, the triggering conditions of the return instruction include at least one of insufficient battery power of the mobile device, insufficient materials, or receiving a user's control instruction. Of course, it can also include return instructions generated by other triggering conditions. The above is only an exemplary scenario description.

[0061] Step S204: Determine whether the return point is available according to the current moment information and the determination time information. If available, execute step S205; otherwise, execute step S206.

[0062] In one embodiment, the judgment process of determining whether the return point is available can be the time point recorded in the determination time information, that is, whether the difference between the time point of determining the return point and the time point of the current moment information is less than the preset interval threshold. If so, it is determined that the return point is available; otherwise, the return point is unavailable. Optionally, the preset interval threshold can be set to be greater than the above preset time and less than twice the above preset time. For example, the preset interval threshold can take any value in the interval (100ms, 200ms), such as 150 milliseconds.

[0063] S205: In response to the judgment result that the return point is available, control the mobile device to return based on the return point.

[0064] S206. In response to the determination result that the return point is unavailable, re-determine the return point based on the current position point, speed information, and acceleration information of the mobile device, and control the mobile device to return based on the re-determined return point.

[0065] In one embodiment, if it is determined that the return point is unavailable, the return point is updated. Among them, the update process of the return point can be exemplary as follows: r2 = p(k) + 0.5 * v(k) * (t dcc +t stop ), where r2 is the updated return point, p(k) is the current position point of the mobile device, v(k) is the current speed of the mobile device, t dcc is the acceleration decay time, t stop is the speed decay time, where t dcc and t stop The calculation methods of are referred to the foregoing exemplary description and will not be elaborated here.

[0066] As can be seen from the above, when controlling the return of the mobile device, the return point is planned in real time, and it is determined whether the return point is available. In the case of availability, a return trajectory is generated based on the determined return point. If it is unavailable, the return point is re-determined, ensuring that the determined return point is available during the navigation of the mobile device, without the need to control the mobile device to hover and then re-plan the return route, nor the need to rely on external additional sensor data conditions, improving the return efficiency of the mobile device, reducing the return time and return distance.

[0067] Figure 4 The flowchart of a method for optimizing a target point provided by an embodiment of the present invention. When controlling the return of the mobile device, the target point is further optimized to further shorten the distance between the target point and the position point, specifically including:

[0068] Step S301. Obtain the position point, speed information, and acceleration information of the mobile device.

[0069] Step S302. Calculate the speed decay time required for the mobile device to decelerate to 0 with the maximum acceleration according to the speed information, and calculate the acceleration decay time required for the mobile device to decelerate to 0 with the maximum jerk according to the acceleration information.

[0070] Step S303. Add the speed decay time and the acceleration decay time to obtain the hover control time required for the mobile device to be in a hover state, and calculate the target point closest to the position point according to the hover control time and the position point.

[0071] Step S304: Calculate the estimated speed information when the mobile device sails from the target point to the position point.

[0072] Exemplarily, the current speed of the mobile device is denoted as v(k), and the estimated speed is denoted as The method for calculating the estimated speed information when the mobile device sails from the target point to the position point is as follows: When the mobile device sails to the current position point with the speed at the target point being 0 and the acceleration being a set constant or variable acceleration, calculate the estimated speed at this time.

[0073] Step S305: Determine the adjustment factor corresponding to the speed decay time according to the estimated speed information and the speed information. The adjustment factor is used to adjust the magnitude of the speed decay time to calculate the optimized target point.

[0074] In one embodiment, after obtaining the estimated speed information, i.e., the estimated speed Compare the estimated speed with the current speed v(k) of the mobile device to determine the adjustment factor corresponding to the speed decay time.

[0075] Specifically, in the case where the speed value of the estimated speed information is greater than the speed value of the speed information, shorten the speed decay time through the adjustment factor; in the case where the speed value of the estimated speed information is less than the speed value of the speed information, increase the speed decay time through the adjustment factor.

[0076] In one embodiment, to ensure the determination of the optimal target point, when is satisfied, that is, is greater than v(k) and the two are close, the determined target point is the most optimal. At this time, after obtaining the actual and v(k), if then the value range of the adjustment factor is set to (0.8, 1), which means that when the current mobile device can plan its state to the previously calculated target point through the optimal trapezoidal speed distribution method, continue to optimize the target point to make the distance between the current position of the mobile device and the target point the shortest, thereby improving the motion efficiency; when is satisfied, the value range of the adjustment factor is (1, 1.2), that is, when the current mobile device cannot plan its state to the calculated target point through the optimal trapezoidal speed distribution method, make the mobile device successfully obtain the reachable target point to plan the operation trajectory based on this. Among them, the updated speed decay time t stop is the product of the originally calculated t stop and the adjustment factor.

[0077] As can be seen from the above, by setting the adjustment factor to adjust the speed decay time, and then adjusting the hover control time, so that the target point planned by the gradient speed distribution method based on this is available and the distance is the closest, which improves the movement efficiency of the mobile device, reduces the movement time and the movement distance; for example, in the return flight scenario, the return efficiency of the mobile device can be improved; in the hover scenario, the hover efficiency of the mobile device can be improved; in the flight path switching scenario, the flight path switching efficiency of the mobile device can be improved; in the terrain-following flight scenario, the operation efficiency of the mobile device can be improved.

[0078] In some embodiments, when the target point is a transition point, the path between the target point and the end point can be further optimized. The following takes the target point as the return point as an example to illustrate the path optimization scheme between the return point and the starting point, as Figure 5 shown. Figure 5 FIG. is a flowchart of a method for planning a return flight trajectory based on a return point provided by an embodiment of the present invention, specifically including:

[0079] Step S401, obtain the position point, speed information and acceleration information of the mobile device.

[0080] Step S402, determine the return point closest to the position point according to the position point, the speed information and the acceleration information.

[0081] Step S403, when receiving the return instruction of the mobile device and determining that the return point is available, obtain the starting departure point of the mobile device, generate a return flight trajectory based on the starting departure point, the return point and the position point as reference points, and control the mobile device to sail along the return flight trajectory.

[0082] In one embodiment, if there is also a safety point set in the area where the mobile device is located, the points obtained above may also include the safety point, that is, a return flight trajectory including the starting departure point, the safety point, the return point and the position point is generated. Among them, the safety point can be a pre-calibrated flight point that the mobile device can pass through safely, and the mobile device will not be affected by obstacles when sailing through it. The starting departure point is the end point that needs to finally return. Here, the starting departure point is used as the end point of the return flight as an example for illustration. The end point of the return flight can be different from the starting departure point. For example, it can be a flight point set different from the starting departure point.

[0083] Optionally, when generating the return flight trajectory, the specific process may be: generating a first planning trajectory based on the position point, the return point and the starting departure point through the optimal trapezoidal speed distribution algorithm; generating a second planning trajectory based on the first planning trajectory by using the B-spline optimization algorithm, wherein the generation of the second planning trajectory includes performing tracking constraint processing on the first planning trajectory through the B-spline optimization algorithm.

[0084] Among them, the generation of the second planned trajectory includes performing a tracking constraint process on the first planned trajectory through a B-spline optimization algorithm. Since the classic trapezoidal speed distribution method can make full use of the maximum values of the speed, acceleration, and jerk of the mobile device for planning and ensure the shortest space of the generated trajectory, the mobile device can return quickly along this first planned trajectory. In addition, further considering the physical constraints of the unmanned aerial vehicle and the obstacles in the environment, on the basis of the first planned trajectory, a B-spline optimization algorithm is used to generate a second planned trajectory to achieve the planning of a barrier-free and smooth return trajectory. Exemplarily, Figure 5a A schematic diagram of a generated return trajectory provided by an embodiment of the present invention is shown in Figure 5a As shown, taking the mobile device as an unmanned aerial vehicle, when the unmanned aerial vehicle moves along the to-be-operated route, the current position point of the unmanned aerial vehicle is denoted as p(k), the estimated return point obtained is r1, the obstacle is the circular area in the figure, the take-off point p2 and the safety point p1 are the obtained waypoints, and the finally generated return trajectory is the smooth and smooth trajectory from the return point through the safety point to the take-off point in the figure.

[0085] Optionally, considering comprehensively the smoothness, kinematic feasibility, safety, tracking constraint, and end constraint of the return trajectory, the objective function of the B-spline optimization with an optimization time domain length of N is set as follows:

[0086]

[0087] Among them, r* is the finally calculated optimal return trajectory.

[0088]

[0089] Among them, C0 is the smoothness constraint, and p μ (i) is the control point at the i-th moment.

[0090]

[0091] Among them, C1 is the kinematic feasibility constraint to constrain the speed and acceleration of the planned trajectory within the maximum speed and the maximum acceleration of the mobile device.

[0092]

[0093] Among them, C2 is the safety constraint for obstacle avoidance to keep the generated trajectory away from obstacles, where

[0094]

[0095] Among them, d safeThe minimum safe distance between the mobile device and the obstacle.

[0096]

[0097] Among them, C3 is a phased tracking constraint to constrain the mobile device to fit as closely as possible to the trajectory r obtained by the optimal trapezoidal speed distribution nominal , so that the mobile device can fly back as quickly as possible.

[0098]

[0099] C4 is an end constraint to stabilize the end of the UAV's trajectory to the desired trajectory r nominal ;

[0100] Among them, Q1 ∈ R + 、Q2 ∈ R + 、Q3 ∈ R + 、Q4 ∈ R + 、Q5 ∈ R + are the weight coefficients of each constraint respectively.

[0101] As can be seen from the above, based on the position point, the return point, the starting point and the safety point, the first planned trajectory is generated by the optimal trapezoidal speed distribution algorithm, and then the second planned trajectory is generated by the B-spline optimization algorithm based on the first planned trajectory. Among them, the generation of the second planned trajectory includes performing tracking constraint processing on the first planned trajectory through the B-spline optimization algorithm, so that the finally generated return trajectory is the shortest and smooth, and the return of the mobile device is realized efficiently.

[0102] On the basis of the above technical solution, controlling the mobile device to navigate along the return trajectory includes: during the process of controlling the mobile device to navigate from the position point to the return point, determining whether to continue the operation according to the remaining material carried by the mobile device. That is, during the process of the mobile device navigating from the current position point to the return point, it can be determined whether to continue the navigation operation according to the remaining material situation. Thus, in the presence of materials, the mobile device can continue the operation, improving the overall operation efficiency of the mobile device and the smoothness of the connection between the operation process and the return process.

[0103] It should be noted that if a safety point is not set in the area where the mobile device operates, it can be considered that the mobile device can directly generate a return trajectory based on the starting point, the return point and the position point without considering the safety point.

[0104] In one embodiment, during the process of trajectory planning after determining the target point, it may further include: uniformly sampling between the position point and the target point to obtain at least two trajectory points; generating a trajectory for guiding the mobile device to move from the position point to the target point based on the position point, the at least two trajectory points, and the target point; the trajectory includes the at least two trajectory points. Among them, uniform sampling can be performed at a fixed time interval. Optionally, in the case of an existing target route, sampling can be performed between the position point and the target point on the target route to obtain multiple trajectory points, so that the generated trajectory from the position point to the target point is more conforming to the target route. Exemplarily, as Figure 6 shown Figure 6 is a schematic diagram of the movement trajectory of an exemplary mobile device provided by an embodiment of the present invention. Among them, the determined estimated return point is r1, the current position point of the mobile device is p(k), and the trajectory points to be operated obtained by uniformly sampling between the position point and the estimated return point are shown in the figure. Optionally, Figure 6 further exemplarily shows the takeoff point p2 and the safety point p1, and the arrowed line segment therein is the target route.

[0105] In one embodiment, during the process of trajectory planning after determining the target point, it may further include: determining at least two virtual control points before the mobile device moves to the position point according to the position point and the acceleration information, for performing trajectory constraint when generating the movement trajectory from the position point to the target point. Exemplarily, with a fixed time interval ΔT as the sampling interval, multiple virtual control points such as M are deduced backward at the position point, and the second difference values between the respective virtual control points are all equal to the acceleration vector of the current mobile device. Exemplarily, as Figure 6 shown, the virtual control points are sampling points with a fixed time interval ΔT deduced backward along the target route from the current position point p(k). During the subsequent process of trajectory planning, these M points can be added to the foregoing respective constraint functions. Thus, by further performing trajectory constraint on the movement trajectory from the position point to the target point based on the virtual control points, the continuity of the acceleration of the mobile device from the position point to the target point and the acceleration of the mobile device before the position point can be ensured, thereby improving the smoothness of the movement of the mobile device, which is beneficial to further improving the smoothness of the movement of the mobile device and reducing the damage to the mechanical structure of the mobile device.

[0106] Figure 7 is a schematic diagram of the modules of a mobile device target point determination device provided by an embodiment of the present invention. This device is used to execute the mobile device target point determination method described above, and has the corresponding functional modules and beneficial effects for executing the method. As Figure 7 shown, this device specifically includes: an information acquisition module 101 and a target point calculation module 102, where,

[0107] An information acquisition module 101, configured to acquire the position points, speed information, and acceleration information of the mobile device;

[0108] A target point calculation module 102, configured to determine the target point closest to the position point according to the position point, the speed information, and the acceleration information, so as to control the mobile device to move based on the target point.

[0109] As can be seen from the above solution, by acquiring the position points, speed information, and acceleration information of the mobile device, the target point closest to the position point is determined according to the position point, the speed information, and the acceleration information, so as to control the mobile device to move based on the target point. This solution improves the movement efficiency of the mobile device, reduces unnecessary travel consumption, and the process of determining the target point does not depend on external conditions.

[0110] In a possible embodiment, the target point includes a return point, and the target point calculation module 102 is configured to:

[0111] Determine the return point closest to the position point on the target route according to the position point, the speed information, and the acceleration information, where the target route includes the route pre-planned during the operation of the mobile device.

[0112] In a possible embodiment, the device further includes a trajectory control module 103, configured to:

[0113] After determining the return point closest to the position point, record the determination time information when determining the return point;

[0114] When receiving the return instruction of the mobile device, obtain the current time information, and determine whether the return point is available according to the current time information and the determination time information, where the triggering conditions of the return instruction include at least one of insufficient battery power, insufficient materials, or receiving a control instruction from the user;

[0115] In response to the judgment result that the return point is available, control the mobile device to return based on the return point.

[0116] In a possible embodiment, the trajectory control module 103 is configured to:

[0117] In response to the judgment result that the return point is unavailable, re-determine the return point based on the current position point, speed information, and acceleration information of the mobile device, so as to control the mobile device to return based on the re-determined return point.

[0118] In a possible embodiment, the target point calculation module 102 is configured to:

[0119] Based on the position point, the velocity information, and the acceleration information, determine the target point closest to the position point based on the trapezoidal velocity distribution algorithm.

[0120] In a possible embodiment, the target point calculation module 102 is configured to:

[0121] Calculate the velocity decay time required for the mobile device to decelerate to 0 when controlling the velocity decay with the maximum acceleration according to the velocity information;

[0122] Calculate the acceleration decay time required for the mobile device to decelerate the acceleration to 0 when controlling the acceleration decay with the maximum jerk according to the acceleration information;

[0123] Add the velocity decay time and the acceleration decay time to obtain the hover control time required for the mobile device to be in the hover state;

[0124] Calculate the target point closest to the position point according to the hover control time and the position point.

[0125] In a possible embodiment, the target point calculation module 102 is further configured to:

[0126] After calculating the target point closest to the position point according to the hover control time and the position point, it further includes: calculating the estimated velocity information when the mobile device moves from the target point to the position point;

[0127] Determine the adjustment factor corresponding to the velocity decay time according to the estimated velocity information and the velocity information, and the adjustment factor is used to adjust the magnitude of the velocity decay time to calculate the optimized target point.

[0128] In a possible embodiment, when the velocity value of the estimated velocity information is greater than the velocity value of the velocity information, shorten the velocity decay time through the adjustment factor, and when the velocity value of the estimated velocity information is less than the velocity value of the velocity information, increase the velocity decay time through the adjustment factor.

[0129] In a possible embodiment, the trajectory control module 103 is further configured to:

[0130] After determining the return point closest to the position point, obtain the starting departure point of the mobile device;

[0131] Generate a return trajectory with the starting departure point, the return point, and the position point as reference points;

[0132] Control the mobile device to move along the return trajectory.

[0133] In a possible embodiment, the trajectory control module 103 is configured to:

[0134] Generate a first planned trajectory based on the position point, the return point, and the starting departure point through an optimal trapezoidal speed distribution algorithm;

[0135] Generate a second planned trajectory based on the first planned trajectory by using a B-spline optimization algorithm, wherein the generation of the second planned trajectory includes performing tracking constraint processing on the first planned trajectory through the B-spline optimization algorithm.

[0136] In a possible embodiment, the trajectory control module 103 is configured to:

[0137] During the process of controlling the mobile device to navigate from the position point to the return point, determine whether to continue the operation process according to the remaining material situation carried by the mobile device.

[0138] In a possible embodiment, the trajectory control module 103 is configured to:

[0139] After determining the target point closest to the position point according to the position point, the speed information, and the acceleration information, uniformly sample between the position point and the target point to obtain at least two trajectory points;

[0140] Generate a trajectory for guiding the mobile device to move from the position point to the target point based on the position point, the at least two trajectory points, and the target point; the trajectory includes the at least two trajectory points.

[0141] In a possible embodiment, the trajectory control module 103 is configured to:

[0142] After determining the target point closest to the position point according to the position point, the speed information, and the acceleration information, determine at least two virtual control points before the mobile device moves to the position point according to the position point and the acceleration information, for performing trajectory constraint when generating the movement trajectory from the position point to the target point.

[0143] In a possible embodiment, the target point includes at least one or more of a transition point between a first operation point and a second operation point with a height difference greater than a set height value, a transition point during the avoidance of high obstacles, a route switching point during route switching, a safe hover end point after avoiding obstacles, or a safe hover end point that needs to perform a hover operation after receiving a hover instruction.

[0144] Figure 8 The following is a schematic structural diagram of a mobile device target point determination device provided by an embodiment of the present invention. As Figure 8 shown, the device includes a processor 201, a memory 202, an input device 203, and an output device 204; the number of processors 201 in the device may be one or more, Figure 8 and one processor 201 is taken as an example here; the processor 201, the memory 202, the input device 203, and the output device 204 in the device may be connected through a bus or other means, Figure 8 and connection through a bus is taken as an example here. The memory 202, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as program instructions / modules corresponding to the mobile device target point determination method in the embodiments of the present invention. The processor 201 executes various functional applications and data processing of the device by running the software programs, instructions, and modules stored in the memory 202, that is, implements the above-mentioned mobile device target determination method. The input device 203 can be used to receive input digital or character information, and generate key signal inputs related to the user settings and function controls of the device. The output device 204 may include a display device such as a display screen.

[0145] An embodiment of the present invention also provides a storage medium containing computer-executable instructions, which can be stored in the form of a server application. The computer-executable instructions, when executed by a computer processor, are used to execute a mobile device target point determination method, and the method includes:

[0146] Obtain the position point, speed information, and acceleration information of the mobile device;

[0147] Determine the target point closest to the position point according to the position point, the speed information, and the acceleration information, so as to control the mobile device to move based on the target point.

[0148] It should be noted that in this text, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising that element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, but may also include performing functions in a substantially simultaneous manner or in the reverse order according to the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted or combined. Additionally, the features described with reference to certain examples may be combined in other examples.

[0149] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described example methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on this understanding, the technical solution of the present application, in essence or the part that contributes to the prior art, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to enable a terminal (which can be a mobile device, mobile phone, computer, server or network device, etc.) to execute the methods described in the various embodiments of the present application.

[0150] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose of the present application and the scope protected by the claims, and all of them fall within the protection scope of the present application.

Claims

1. Method for determining target point of mobile device, characterized in that, Including: Obtain the position points, speed information, and acceleration information of the mobile device; Determine the target point closest to the position point according to the position point, the speed information, and the acceleration information, where it includes: Calculate the speed decay time required for the mobile device to decelerate to 0 with the maximum acceleration according to the speed information, calculate the acceleration decay time required for the mobile device to decelerate to 0 with the maximum jerk according to the acceleration information, add the speed decay time and the acceleration decay time to obtain the hover control time required for the mobile device to be in a hover state, calculate the target point closest to the position point according to the hover control time and the position point, so as to control the mobile device to move based on the target point, and the target point closest to the position point is the return point closest to the position point.

2. The method for determining the target point of a mobile device according to claim 1, wherein The target point includes a return point, and determining the target point closest to the position point according to the position point, the speed information, and the acceleration information includes: Determine the return point closest to the position point on the target route according to the position point, the speed information, and the acceleration information, where the target route includes the route pre-planned during the operation of the mobile device.

3. The method for determining a target point of a mobile device according to claim 2, wherein, After determining the return point closest to the position point, the method further includes: Record the determination time information when determining the return point; When receiving the return instruction of the mobile device, obtain the current time information, and determine whether the return point is available according to the current time information and the determination time information. The triggering conditions of the return instruction include at least one of insufficient battery power, insufficient materials, or receiving a user control instruction of the mobile device; In response to the judgment result that the return point is available, control the mobile device to return based on the return point.

4. The method for determining a target point of a mobile device according to claim 3, wherein After determining the return point closest to the position point, the method further includes: In response to the judgment result that the return point is unavailable, re-determine the return point based on the current position point, speed information, and acceleration information of the mobile device, so as to control the mobile device to return based on the re-determined return point.

5. The method for determining the target point of the mobile device according to claim 1, wherein After calculating the target point closest to the position point according to the hover control time and the position point, the method further includes: Calculate the estimated speed information when the mobile device moves from the target point to the position point; Determine the adjustment factor corresponding to the speed decay time according to the estimated speed information and the speed information, and the adjustment factor is used to adjust the size of the speed decay time to calculate the optimized target point.

6. The method for determining the target point of a mobile device according to claim 5, wherein In the case where the speed value of the estimated speed information is greater than the speed value of the speed information, shorten the speed decay time through the adjustment factor; in the case where the speed value of the estimated speed information is less than the speed value of the speed information, increase the speed decay time through the adjustment factor.

7. The method for determining a target point of a mobile device according to claim 2, wherein After determining the return point closest to the position point, the method further includes: Obtain the starting point of the mobile device; Generate a return flight trajectory based on the starting point, the return point, and the position point as reference points; Control the mobile device to move along the return flight trajectory.

8. The method for determining the target point of a mobile device according to claim 7, wherein The generating a return flight trajectory based on the starting point, the return point, and the position point as reference points includes: Generate a first planned trajectory based on the position point, the return point, and the starting point through an optimal trapezoidal speed distribution algorithm; Generate a second planned trajectory based on the first planned trajectory using a B-spline optimization algorithm, wherein the generation of the second planned trajectory includes performing a tracking constraint process on the first planned trajectory through the B-spline optimization algorithm.

9. The method for determining the target point of a mobile device according to claim 7, characterized in that, The controlling the mobile device to sail along the return flight trajectory includes: During the process of controlling the mobile device to sail from the position point to the return point, determine whether to continue the operation according to the remaining material carried by the mobile device.

10. The method for determining a target point of a mobile device according to claim 1, wherein After determining the target point closest to the position point according to the position point, the speed information, and the acceleration information, the method further includes: Perform uniform sampling between the position point and the target point to obtain at least two trajectory points; Generate a trajectory for guiding the mobile device to move from the position point to the target point based on the position point, the at least two trajectory points, and the target point; the trajectory includes the at least two trajectory points.

11. The method for determining a target point of a mobile device according to claim 1, wherein After determining the target point closest to the position point according to the position point, the speed information, and the acceleration information, it further includes: Determine at least two virtual control points before the mobile device moves to the position point according to the position point and the acceleration information, for trajectory constraint when generating the movement trajectory from the position point to the target point.

12. The method for determining a target point of a mobile device according to claim 1, characterized in that, The target point includes at least one or more of a transition point between a first working point and a second working point with a height difference greater than a set height value, a transition point during obstacle avoidance for high obstacles, a route switching point during route switching, a safe hover end point after avoiding an obstacle, or a safe hover end point that needs to perform a hover operation after receiving a hover instruction.

13. Mobile device target point determination device, characterized in that, Includes: An information acquisition module configured to acquire the position point, speed information, and acceleration information of the mobile device; A target point calculation module, configured to determine a target point closest to the position point according to the position point, the speed information, and the acceleration information, for controlling the mobile device to move based on the target point, where the target point closest to the position point is the return point closest to the position point. The target point calculation module is specifically configured to calculate, according to the speed information, the speed decay time required for the mobile device to decay to a speed of 0 when performing speed decay control with the maximum acceleration, calculate, according to the acceleration information, the acceleration decay time required for the mobile device to decay to an acceleration of 0 when performing acceleration decay control with the maximum jerk, add the speed decay time and the acceleration decay time to obtain the hover control time required for the mobile device to be in a hover state, and calculate the target point closest to the position point according to the hover control time and the position point.

14. Mobile device target point determination device, the device comprising: One or more processors; A storage device for storing one or more programs, which when executed by the one or more processors cause the one or more processors to implement the method for determining the target point of the mobile device according to any one of claims 1-12.

15. A storage medium storing computer-executable instructions, which are used to execute the method for determining the target point of the mobile device according to any one of claims 1-12 when executed by a computer processor.

Images