Time-continuous acquisition method of robot path nodes

Abstract

The present invention discloses a time-continuous acquisition method for a robot's path node. Before executing the time-continuous acquisition method, the robot obtains a path node at two adjacent moments in a moving process; the robot does not obtain a path node within the time interval between the two adjacent moments; the time-continuous acquisition method comprises: according to the change of the robot's posture between the two adjacent moments, obtaining the robot's posture at a time to be measured, wherein the time to be measured is within the time interval between the two adjacent moments obtained in advance; wherein the robot's posture includes the length of the robot's radial segment at the path node, the angle of the robot's direction angle at the path node, and the angle value of the robot's rotation angle at the path node.

Description

Technical Field

[0001] The present invention relates to the technical field of robot path node processing, and in particular to a method for time-continuous acquisition of robot path nodes. Background Art

[0002] During the process of autonomous movement and timely positioning, the mobile robot will only generate posture information at regular intervals. Therefore, the robot will only mark discrete path nodes in the map constructed in a timely manner. Therefore, in the process of trajectory prediction between two adjacent moments, only the posture information of a limited number of path nodes is used for prediction, resulting in poor temporal continuity of the generated robot motion trajectory. Summary of the Invention

[0003] In order to improve the continuity of the robot's motion trajectory, the present invention discloses a method for obtaining the robot's path nodes in a time-continuous manner. In particular, between discretely distributed path nodes, the path nodes are calculated by a fixed change rate or time interval ratio to obtain the posture at any time within the continuous time period between two adjacent moments. The specific technical solution is as follows:

[0004] A time-continuous acquisition method for a robot's path node, before executing the time-continuous acquisition method, the robot obtains a path node at each of two adjacent moments during the movement process; the robot does not obtain a path node within the time interval between the two adjacent moments; the time-continuous acquisition method includes: according to the change of the robot's posture between the two adjacent moments, obtaining the robot's posture at the time to be measured, wherein the time to be measured is within the time interval between the two adjacent moments obtained in advance; wherein the robot's posture includes the length of the robot's radial line segment at the path node, the angle of the robot's direction angle at the path node, and the angle value of the robot's rotation angle at the path node.

[0005] Furthermore, the time continuity acquisition method also includes: setting two adjacent moments obtained in advance as the first moment and the second moment respectively, wherein the first moment is smaller than the second moment, and the time difference between the second moment and the first moment is fixed; wherein, calculating the time difference between the second moment and the first moment, and setting the time difference as the total time interval; calculating the time difference between the moment to be measured and the first moment, and setting the time difference as the time difference to be measured.

[0006] Further, the robot sets the path node obtained at the first moment as the first path node, and the robot sets the path node obtained at the second moment as the second path node; the robot sets its forward direction at the first path node as the first forward direction, and then sets the straight line passing through the first path node and perpendicular to the first forward direction as the first preset straight line; the robot sets its forward direction at the second path node as the second forward direction, and then sets the straight line passing through the second path node and perpendicular to the second forward direction as the second preset straight line.

[0007] Furthermore, the method for obtaining the posture of the robot at the time to be tested based on the change of the posture of the robot between two adjacent moments is: obtaining the posture of the robot at the time to be tested based on the change rate of the posture of the robot between two adjacent moments; wherein the change rate of the posture of the robot between two adjacent moments includes: the length change rate of the radial line segment of the robot between the second moment and the first moment, the angular change rate of the direction angle of the robot between the second moment and the first moment, and the angular change rate of the rotation angle of the robot between the second moment and the first moment.

[0008] Furthermore, the method for obtaining the posture of the robot at the time to be measured based on the rate of change of the posture of the robot between two adjacent moments includes: calculating the difference between the length of the second radial line segment and the length of the first radial line segment, and setting the difference as the total incremental value of the radial line segment; then setting the ratio of the total incremental value of the radial line segment to the total time interval as the rate of change of the length of the robot's radial line segment between the two adjacent moments, then multiplying the time difference to be measured by the rate of change of the length of the robot's radial line segment between the two adjacent moments, and then setting the obtained product as the effective length change of the robot's radial line segment; then multiplying the length of the first radial line segment by the effective length change of the robot's radial line segment The sum of the degree changes is set as the length of the radial line segment of the robot at the time to be measured, which is used to represent the length of the radial line segment at the path node corresponding to the robot at the time to be measured; wherein, when the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; then the line segment connecting the search center and the first path node is set as the first radial line segment of the robot, and the line segment connecting the search center and the second path node is set as the second radial line segment of the robot; wherein, the first radial line segment of the robot is the radial line segment of the robot at the first moment, and the second radial line segment of the robot is the radial line segment of the robot at the second moment.

[0009] Furthermore, the method for obtaining the posture of the robot at the time to be measured based on the rate of change of the posture of the robot between two adjacent moments includes: calculating the difference between the angle of the second direction angle and the angle of the first direction angle, and setting the difference as the total incremental value of the direction angle; then setting the ratio of the total incremental value of the direction angle to the total time interval as the angle change rate of the robot's direction angle between the two adjacent moments, then multiplying the time difference to be measured by the angle change rate, and then setting the obtained product as the effective angle change of the robot's direction angle; then setting the sum of the length of the first direction angle and the effective angle change of the robot's direction angle as the angle of the robot's direction angle at the time to be measured, which is used to represent the angle of the robot's direction angle at the path node corresponding to the time to be measured; wherein, the angle formed by the first forward direction and the baseline is set as the first direction angle of the robot; the first direction angle of the robot is the direction angle of the robot at the first moment; wherein, the angle formed by the second forward direction and the baseline is set as the second direction angle of the robot; the second direction angle of the robot is the direction angle of the robot at the second moment.

[0010] Furthermore, the method for obtaining the posture of the robot at the time to be measured based on the rate of change of the posture of the robot between two adjacent moments includes: setting the ratio of the preset rotation angle to the total time interval as the angle change rate of the robot's rotation angle between the two adjacent moments, then multiplying the time difference to be measured by the angle change rate, and then setting the obtained product as the angle of the robot's rotation angle at the time to be measured, which is used to represent the angle of the rotation angle of the robot at the path node corresponding to the time to be measured; wherein, when the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; in the first preset straight line, the ray pointing from the search center to the first path node is set as the first ray; in the second preset straight line, the ray pointing from the search center to the second path node is set as the first ray; then, the angle formed by the first ray and the second ray is set as the preset rotation angle; wherein, the rotation angle of the robot at the path node corresponding to the time to be measured is the angle formed by the ray pointing from the search center to the path node relative to the first ray.

[0011] Furthermore, the method for obtaining the posture of the robot at the time to be measured based on the change of the posture of the robot between two adjacent moments is: obtaining the posture of the robot at the time to be measured based on the change of the time weight of the posture of the robot in the time interval between two adjacent moments; wherein, the proportion of the time difference to be measured in the total time interval is used to represent the change of the time weight of the posture of the robot in the time interval between two adjacent moments; wherein, the ratio of the time difference to be measured to the total time interval is set as the time change ratio.

[0012] Furthermore, the method for obtaining the posture of the robot at the time to be measured based on the time weight change of the posture of the robot within the time interval between two adjacent moments includes: calculating the difference between the length of the second radial line segment and the length of the first radial line segment, and setting the difference as the total incremental value of the radial line segment; then setting the product of the total incremental value of the radial line segment and the time change ratio as the effective length change of the radial line segment of the robot; then setting the sum of the length of the first radial line segment and the effective length change of the radial line segment of the robot as the length of the radial line segment of the robot at the time to be measured, which is used to represent the length of the radial line segment at the path node corresponding to the robot at the time to be measured; wherein, when the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; then setting the line segment connecting the search center and the first path node as the first radial line segment of the robot, and setting the line segment connecting the search center and the second path node as the second radial line segment of the robot; wherein the first radial line segment of the robot is the radial line segment of the robot at the first moment, and the second radial line segment of the robot is the radial line segment of the robot at the second moment.

[0013] Furthermore, the method for obtaining the posture of the robot at the time to be measured based on the change in the time weight of the robot's posture within the time interval between two adjacent moments includes: calculating the difference between the angle of the second direction angle and the angle of the first direction angle, and setting the difference as the total incremental value of the direction angle; then setting the product of the total incremental value of the direction angle and the time change ratio as the effective angle change of the robot's direction angle; then setting the sum of the length of the first direction angle and the effective angle change of the robot's direction angle as the angle of the robot's direction angle at the time to be measured, which is used to represent the angle of the robot's direction angle at the path node corresponding to the time to be measured; wherein, the angle formed by the first forward direction and the baseline is set as the first direction angle of the robot; the first direction angle of the robot is the direction angle of the robot at the first moment; wherein, the angle formed by the second forward direction and the baseline is set as the second direction angle of the robot; the second direction angle of the robot is the direction angle of the robot at the second moment.

[0014] Furthermore, the method for obtaining the posture of the robot at the time to be measured based on the change in the time weight of the robot's posture within the time interval between two adjacent moments includes: setting the product of the preset rotation angle and the time change ratio as the angle of the rotation angle of the robot at the time to be measured, which is used to represent the angle of the rotation angle of the robot at the path node corresponding to the time to be measured; wherein, when the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; in the first preset straight line, the ray pointing from the search center to the first path node is set as the first ray; in the second preset straight line, the ray pointing from the search center to the second path node is set as the first ray; and then, the angle formed by the first ray and the second ray is set as the preset rotation angle.

[0015] Furthermore, any moment within the time interval between the second moment and the first moment corresponds to a path node, and the larger the moment to be measured is, the closer the calculated posture of the path node is to the posture of the second path node.

[0016] Compared to the prior art, the present invention controls the radial distance, rotation angle, and azimuth angle of a path node within the time interval between two adjacent moments to calculate the pose information at the time to be measured at a fixed rate of change, thereby obtaining the pose information of a predicted path node corresponding to the time to be measured. Furthermore, the pose information at the time to be measured is converted based on the ratio of the time interval between the time to be measured and the starting moment (the first moment disclosed in the aforementioned technical solution) to the total time interval, thereby obtaining the pose information at any moment in a continuous time period. This overcomes the problem of insufficient temporal continuity in the robot motion trajectory formed by inserting a limited number of path nodes between two discretely distributed locations, and makes it easier to obtain more representative pose information within a continuous time period than the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of obtaining the position information of a position point P3 at a time to be measured between a point P1 obtained at a first time and a point P2 obtained at a second time, disclosed in another embodiment of the present invention. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings in the embodiments of the present invention.

[0019] The embodiment of the present invention provides a method for obtaining the path nodes of a robot in a time-continuous manner, which can be applied to mobile robots, especially mobile robots working in indoor environments, such as sweeping robots, inspection robots, unmanned sampling robots, unmanned forklifts, etc. The mobile robot includes a robot body, a sensor, a controller, and a walking mechanism. The robot body is the main structure of the robot, and the corresponding shape, structure, and manufacturing material (such as hard plastic or metals such as aluminum and iron) can be selected according to the actual needs of the robot. For example, if it is set to a relatively flat cylindrical shape commonly seen in sweeping robots, the projection of the sweeping robot on the ground it is moving is a circle, such as Figure 1 As shown by the large circles at the positions P1 and P2; the walking mechanism is provided on the robot body, and is a structural device that provides the mobile robot with mobility. The walking mechanism can be implemented by any type of mobile device, such as rollers, crawlers, etc. The sensor is used to sense the external environment, obtain the coordinate information and angle information of the body itself, and constitute the posture information of the body itself; the sensor can specifically adopt any type of existing information acquisition equipment, including but not limited to an odometer for measuring the walking distance, a gyroscope for measuring the rotation angle of the body, an infrared sensor for ranging, or a visual sensor for ranging. The robot converts the information fed back by these sensors into position information and marks it on the map constructed in real time. The sensor can be set to one or more to meet the detection range of multiple angles.

[0020] At present, a mobile robot generates a position point only at a certain sampling time interval, resulting in two adjacent position points being relatively discrete. The robot will only mark discrete path nodes in the map constructed in a timely manner. The existing technology predicts the robot's motion trajectory by inserting a limited number of path nodes between two path nodes that are far apart. However, these limited number of inserted path nodes cannot be the position points that the mobile robot has moved to at any time within the sampling time interval between the two aforementioned path nodes that are far apart. Among them, the inserted position points are predicted position points, which represent the position points that the mobile robot has moved to at the corresponding time.

[0021] An embodiment of the present invention discloses a time-continuous acquisition method for a robot's posture. Before executing the time-continuous acquisition method, the robot obtains a path node at two adjacent moments in the movement process, that is, a path node is obtained at each of the two adjacent moments; the robot does not obtain a path node within the time interval between the two adjacent moments; wherein, the sensor samples a position point at a certain time interval, and marks the position information of the position point sampled by the sensor to the corresponding coordinate point on the map, such as Figure 1The position points P1 and P2 shown in the figure are the path nodes that the robot has actually moved. In the actual physical environment, the robot walks along a continuous motion trajectory during its movement from one moment to another. However, the robot does not mark each position point it has actually moved to on the map one by one, but instead samples a position point at every time interval.

[0022] In order to make the generated robot motion trajectory more continuous and comprehensive in time, and to obtain representative posture information at any time, the time continuity acquisition method includes obtaining the posture of the robot at the time to be measured based on the change of the robot's posture between two adjacent moments, wherein the time to be measured is within the time interval of the two adjacent moments obtained in advance. This embodiment obtains the change of the robot's posture between two adjacent moments from multiple dimensions. It can be that the change of the robot's posture between two moments is averaged in the dimension of change rate to obtain the average change rate of the robot in the time interval of the two adjacent moments, and the posture information at any moment in the time interval of the two adjacent moments can be obtained based on the average change rate of the relevant posture; it can also be that the weight of the robot's posture change in a certain time interval accounts for the weight of the posture change in the time interval of the two adjacent moments in the dimension of change weight, and then the posture information at any moment in the time interval of the two adjacent moments is obtained, wherein the weight can be converted into the ratio of the time interval between the time to be measured and one of the two adjacent moments to the time interval of the two adjacent moments for calculation. This overcomes the problem of insufficient temporal continuity of the robot's motion trajectory formed by inserting a limited number of path nodes between two discretely distributed position points, and makes it easier to obtain more representative posture information within a continuous time period than existing technologies.

[0023] It should be noted that the execution entity of the time-continuous acquisition method is the robot's internal main control device. This main control device can be an electronic device, including a wireless transceiver; a control circuit board; or a chip with sufficient memory and high integration. In this specification, the execution of corresponding steps by the robot's internal main control device is referred to as "the robot executing corresponding steps." If the execution entity is not specified, the robot or its main control device is assumed to be the execution entity.

[0024] In this embodiment, the robot's posture includes the length of the robot's radial segment at the path node, the angle of the robot's azimuth at the path node, and the angle value of the robot's rotation angle at the path node; the length of the robot's radial segment at the path node, the angle of the robot's azimuth at the path node, and the angle value of the robot's rotation angle at the path node are independent of each other, and the method of obtaining these three types of physical quantities and the method of calculating their changes in the time interval between the two adjacent moments are carried out synchronously, and do not reference related parameters to each other. The synchronous calculation of the changes in these three physical quantities can avoid the prior art of directly using the coordinate information and angle information output by the robot in real time during movement and performing trajectory prediction calculations after coordinate system conversion, thereby reducing the errors between dimensional transformations.

[0025] Based on the above embodiment, the robot sets two pre-acquired adjacent moments as the first and second moments, respectively, where the time difference between the second moment and the first moment is fixed, and the first moment is smaller than the second moment. In this embodiment, the robot first records the first moment and then records the second moment. After recording the second moment, the robot indicates that it has reached a sampling time interval. The time to be measured is any moment within the time interval between the two pre-acquired adjacent moments. In this embodiment, the robot calculates the time difference between the second moment and the first moment and sets this time difference as the total time interval to determine the time range of the time to be measured. The robot also calculates the time difference between the time to be measured and the first moment and sets this time difference as the time difference to be measured to determine the time offset of the time to be measured relative to the first moment, thereby determining the duration of the robot's posture change. In this embodiment, the robot selects the first of the two adjacent moments as the starting moment, which in this embodiment is the first moment. At this moment, a corresponding path node is recorded as the starting path node, and the posture information of the starting path node is recorded as the starting posture information. Combined with the aforementioned rate of change or amount of change, the robot's posture at the time to be measured can be calculated.

[0026] On the basis of the above embodiment, the robot sets the path node obtained at the first moment as the first path node, and sets the path node obtained at the second moment as the second path node; correspondingly, Figure 1 In the example, the first path node is position point P1, the second path node is position point P2, and each moment corresponds to a path node that has actually been moved or a predicted path node. The robot sets its forward direction at the first path node as the first forward direction, which is also the forward direction of the robot at the first moment. Then, a straight line passing through the first path node and perpendicular to the first forward direction is set as the first preset straight line, corresponding to Figure 1The arrow at position point P1 is shown as the first preset straight line. The robot sets its forward direction at the second path node as the second forward direction, which is also the forward direction of the robot at the second moment. Then, the straight line passing through the second path node and perpendicular to the second forward direction is set as the second preset straight line, corresponding to Figure 1 As indicated by the arrow pointing at the position point P2, the second preset straight line is the straight line OP2.

[0027] When the first preset straight line intersects with the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center, and the forward direction of the robot at any path node remains perpendicular to the line connecting the position point and the search center. Then, the forward direction of the robot at any path node is determined to be the tangent direction at the path node, which is the tangent direction of a path node in the actual motion trajectory recorded by the robot or the tangent direction of a predicted path node in the predicted motion trajectory to which it belongs. Therefore, this embodiment can mark the rotation trajectory of the robot and the position information of the path node at any time within an angle range formed by the intersection of the second preset straight line and the first preset straight line with the search center as the vertex, and form the position information of the robot in a continuous time interval within the angle range, replacing the discretely distributed path nodes and their position information periodically collected by the robot sensor in the prior art.

[0028] As a first embodiment, the method for obtaining the posture of the robot at the time to be measured based on the change of the posture of the robot between two adjacent moments is: obtaining the posture of the robot at the time to be measured based on the rate of change of the posture of the robot between two adjacent moments. In the first embodiment, the rate of change of the posture of the robot between two adjacent moments includes: the rate of change of the length of the radial line segment of the robot between the second moment and the first moment, the rate of change of the angle of the robot's orientation between the second moment and the first moment, and the rate of change of the angle of the robot's rotation between the second moment and the first moment. The aforementioned rates of change can be expressed as average rates of change, although only the result of processing the postures at two moments; in some embodiments, the rate of change of the length of the radial line segment of the robot between the second moment and the first moment is the average rate of change of the length of the radial line segment during the time interval between the second moment and the first moment, and the rate of change of the angle of the radial line segment of the robot between the second moment and the first moment is the average rate of change of the angle of the orientation during the time interval between the second moment and the first moment; in some embodiments, the rate of change of the angle of the robot's rotation between the second moment and the first moment can be expressed as the average rate of change of the angle of the rotation during the time interval between the second moment and the first moment.

[0029] As a specific implementation of Example 1, when the robot posture to be calculated is the length of a radial line segment, the method for obtaining the robot posture at the time to be measured based on the rate of change of the robot posture between two adjacent moments includes:

[0030] When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; then the line segment connecting the search center and the first path node is set as the first radial line segment of the robot, and the line segment connecting the search center and the second path node is set as the second radial line segment of the robot, wherein the first radial line segment of the robot is the radial line segment of the robot at the first moment, and the second radial line segment of the robot is the radial line segment of the robot at the second moment; the forward direction of the robot at the first path node is perpendicular to the first radial line segment, and the forward direction of the robot at the second path node is perpendicular to the second radial line segment; when the forward direction of the robot changes, that is, it is predicted or planned to be at the first moment The forward direction of the robot between the first moment and the second moment deflects at a certain angle, indicating that the robot rotates. The robot may actually rotate and form an arc trajectory between the first moment and the second moment. Then, the line segment formed by connecting the search center and a predicted path node at the time to be measured (which can be understood as a path node inserted between the first preset straight line and the second preset straight line, a path node inserted between the second path node and the first path node, and a path node inserted within an angle range formed by the intersection of the second radial line segment and the first radial line segment) becomes a radial line segment predicted at the time to be measured, which is used to represent the distance information of the robot deviating from the search center, thereby using spatial coordinates or line segment length information. Accordingly, at Figure 1 In the figure, position point P3 is the predicted position point at the time to be tested, O is the search center, and line segment OP3 is a radial line segment determined at the time to be tested. The direction of the arrow at position point P3 is perpendicular to line segment OP3 because the line connecting the path node at any time and the search center remains perpendicular to the forward direction of the robot at that time.

[0031] On this basis, the robot calculates the difference between the length of the second radial line segment and the length of the first radial line segment, and sets the difference as the total incremental value of the radial line segment, which is used to represent the difference between the length of the radial line segment at the two adjacent moments, that is, the difference between the length of the radial line segment at the second moment and the length of the radial line segment at the first moment, which can represent the change and value of the length of the radial line segment between the two adjacent moments; wherein, this embodiment sets the first radial line segment as the initial radial line segment, so that the length of the radial line segment at any subsequent moment is calculated based on the length of the first radial line segment, and the first moment is selected as the starting moment of the calculation. To obtain the length of the robot's radial segment at the time to be measured, the robot sets the ratio of the total incremental value of the radial segment to the total time interval as the length change rate of the robot's radial segment between the two adjacent moments, which can represent the rate of change of the length of the robot's radial segment in the time interval between the second moment and the first moment. The robot then multiplies the time difference to be measured by the length change rate, and the resulting product is set as the effective length change of the robot's radial segment, which serves as the predicted length change of the radial segment during the robot's movement from the first moment to the time to be measured, i.e., the change in the distance between the robot's moving position and the same search center. The dimension of the length change rate of the robot's radial segment between the two adjacent moments is the same as the dimension of velocity, corresponding to centimeters per second or meters per second in the International System of Units; the time difference to be measured is in seconds. Therefore, the robot sets the sum of the length of the first radial segment and the effective length change of the robot's radial segment as the length of the robot's radial segment at the time to be measured, representing the length of the radial segment at the path node corresponding to the time to be measured.

[0032] As another specific implementation of Example 1, when the robot posture to be calculated is an angle of direction, the method for obtaining the posture of the robot at the time to be measured based on the rate of change of the robot posture between two adjacent moments includes:

[0033] The robot sets the angle between the first forward direction and the baseline as the robot's first direction angle; the robot's first direction angle is the robot's direction angle at the first moment; the robot also sets the angle between the second forward direction and the baseline as the robot's second direction angle; the robot's second direction angle is the robot's direction angle at the second moment. The robot's direction angle is used to represent the angular characteristics of the robot's forward direction at a path node. It belongs to the robot navigation direction carried by a path node. It can be the angle relative to one of the coordinate axes of the map coordinate system, or it can be the axis of one of the coordinate axes of the map coordinate system, so that the direction angle and its angle can adapt to different types of map marking methods, where the map is constructed by the robot and is used to mark path nodes. Corresponding to Figure 1 In the example, when the path node to be calculated is P3, the direction angle at the path node is the angle between the arrow direction at the position point P3 and the reference line ( Figure 1 The included angle (not shown) is used to represent the angular characteristics of the robot's forward direction at position point P3.

[0034] On this basis, the robot calculates the difference between the angle of the second direction angle and the angle of the first direction angle, and sets the difference as the total incremental value of the direction angle, which is the angular change of the robot's direction angle between the two adjacent moments, and can represent the angle at which the robot's forward direction deflects within the time interval between the two adjacent moments. In particular, when the angle of the robot's direction angle monotonically increases or decreases within the time interval between the two adjacent moments, the angular change at any moment relative to the first moment within the time interval between the two adjacent moments can be controllable. Among them, this embodiment sets the first direction angle as the initial direction angle, which is used as the starting position information for predicting subsequent angles, so that the angle of the direction angle at any subsequent moment is calculated based on the angle of the first direction angle. The robot then sets the ratio of the total incremental value of the orientation angle to the total time interval as the angular change rate of the robot's orientation angle between the two adjacent moments, which can be considered the average angular change rate of the orientation angle within the total time interval. The robot then multiplies the time difference to be measured by this angular change rate, and the resulting product is set as the effective angular change of the robot's orientation angle, which serves as the angular change of the robot's orientation angle predicted during the time interval from the first moment to the time to be measured, i.e., the deflection angle of the robot's forward direction during this time interval. The angular change rate of the robot's orientation angle between the two adjacent moments has the same dimension as the angular velocity, corresponding to rad / s or degrees / s in the International System of Units; the time difference to be measured is in seconds. The sum of the length of the first orientation angle and the effective angular change of the robot's orientation angle is then set as the angle of the robot's orientation angle at the time to be measured, representing the angle of the robot's orientation angle at the path node corresponding to the time to be measured, relative to the baseline.

[0035] As another specific implementation of Example 1, when the robot posture to be calculated is a rotation angle, the method for obtaining the posture of the robot at the time to be measured based on the rate of change of the robot posture between two adjacent moments includes:

[0036] When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; in the first preset straight line, the robot sets the ray pointing from the search center to the first path node as the first ray; in the second preset straight line, the robot sets the ray pointing from the search center to the second path node as the second ray; then the angle between the first ray and the second ray is set as the preset rotation angle, corresponding to Figure 1In the example, the intersection of the second preset straight line OP2 and the first preset straight line OP1 is set as the search center O, the ray from the search center O to the first path node P1 is set as the first ray OP1, the ray from the search center O to the second path node P2 is set as the second ray OP2, and the angle formed by the first ray OP1 and the second ray OP2 is set as the preset rotation angle P1OP2. Specifically, the robot's rotation angle at the first path node P1 is the angle formed by the first ray OP1 and the first ray OP1, that is, the robot's rotation angle at the first path node P1 is equal to 0; the robot's rotation angle at the second path node P2 is the angle formed by the second ray OP2 and the first ray OP1, that is, the robot's rotation angle at the second path node P2 is equal to the angle P1OP2. The robot's rotation angle at the path node corresponding to the time to be measured is the angle formed by the ray from the search center to the path node relative to the first ray. Therefore, when the robot's rotation angle changes, it indicates that the robot is rotating around the search center and forming an arc trajectory between the first and second moments.

[0037] On this basis, the robot sets the ratio of the preset rotation angle to the total time interval as the angle change rate of the robot's rotation angle between the two adjacent moments. At this time, the preset rotation angle represents the amount of angle change of the robot's rotation angle between the two adjacent moments, which is regarded as the sum of the azimuth angle changes formed by the robot's rotation within the total time interval; the angle change rate can be used as the angle between the two path nodes that the robot passes through successively and the line connecting the search center within the time interval between the first moment and the second moment. Here, the time interval between the robot passing through the path nodes is relatively small, so that the angle change rate can also evenly divide the spacing angle value of the preset rotation angle. Then multiply the time difference to be measured by the angle change rate, and then set the obtained product as the angle of the robot's rotation angle at the moment to be measured, which is used to represent the angle of the robot's rotation angle at the path node corresponding to the moment to be measured, specifically the angle of the ray from the search center to the path node corresponding to the moment to be measured relative to the first ray. Corresponding to Figure 1 In the figure, when a path node corresponding to the time to be measured is P3, the rotation angle of the robot at the path node is the angle P3OP1 formed by the ray OP3 and the first ray PO1, which is used to represent the rotation angle of the robot at position P3 relative to the first path node P1 around the search center O.

[0038] In summary, Example 1 calculates the posture information of the path node at any moment within the time interval between the first moment and the second moment between the first path node and the second path node by calculating the angle change rate and the length change rate. The angle change rate and the length change rate can be calculated under the premise that the parameters do not affect each other, so as to obtain two posture information of different dimensions. While ensuring the time continuity of the obtained posture information, it can also reduce the phenomenon of introducing the mechanical error of the posture information of one dimension into the posture information of another dimension.

[0039] As a second embodiment, the method for obtaining the posture of the robot at the time to be measured based on the change of the posture of the robot between two adjacent moments is as follows: according to the change of the time weight of the posture of the robot in the time interval between the two adjacent moments, the posture of the robot at the time to be measured is obtained; wherein, the proportion of the time difference to be measured in the total time interval is used to represent the change of the time weight of the posture of the robot in the time interval between the two adjacent moments; wherein, the ratio of the time difference to be measured to the total time interval is set as the time change ratio. In the second embodiment, the ratio of the time interval of the time to be measured relative to one of the two adjacent moments to the time interval between the two adjacent moments has the meaning of calculating the change in the time dimension. Therefore, in this embodiment, the ratio of the time interval of the time to be measured relative to the first moment to the time interval between the two adjacent moments is set as the degree of change of the posture of the robot in the time interval between the time to be measured relative to the first moment. In embodiment 2, the ratio of the time interval of the moment to be measured relative to the first moment to the time interval of the two adjacent moments is set to be equal to the ratio of the change of the robot's posture in the time interval of the moment to be measured relative to the first moment to the change of the same posture of the robot in the time interval of the two adjacent moments.

[0040] As a specific implementation of Example 2, when the robot posture to be calculated is the length of a radial line segment, the method for obtaining the robot posture at the time to be measured based on the change in the time weight of the robot posture within the time interval between two adjacent moments includes:

[0041] When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; then the line segment connecting the search center and the first path node is set as the first radial line segment of the robot, and the line segment connecting the search center and the second path node is set as the second radial line segment of the robot, wherein the first radial line segment of the robot is the radial line segment of the robot at the first moment, and the second radial line segment of the robot is the radial line segment of the robot at the second moment; the forward direction of the robot at the first path node is perpendicular to the first radial line segment, and the forward direction of the robot at the second path node is perpendicular to the second radial line segment

[0042] Then, the robot calculates the difference between the length of the second radial segment and the length of the first radial segment, and sets the difference as the total incremental value of the radial segment, which is used to represent the length change of the radial segment of the robot at the second moment relative to the radial segment at the first moment; then the product of the total incremental value of the radial segment and the time change ratio is set as the effective length change of the radial segment of the robot; specifically, the robot will set the ratio of the time difference to be measured to the total time interval as the time change ratio, which is used to represent the ratio of the time spent by the moment to be measured relative to the first moment to the time interval between two adjacent moments, which is represented by the total incremental value of the radial segment. , the weight of the robot's posture change at the time to be measured relative to the first moment; then multiply the total incremental value of the radial segment by the time change ratio to obtain the effective length change of the robot's radial segment, as the predicted length change of the radial segment in the process of the robot moving from the first moment to the time to be measured, that is, the change in the distance between the robot's moving position and the same search center; then the robot sets the sum of the length of the first radial segment and the effective length change of the robot's radial segment as the length of the robot's radial segment at the time to be measured, which is used to represent the length of the radial segment at the path node corresponding to the robot at the time to be measured. Correspondingly, Figure 1 In the figure, position point P3 is the predicted position point at the time to be tested, O is the search center, and line segment OP3 is a radial line segment determined at the time to be tested. The direction of the arrow at position point P3 is perpendicular to line segment OP3 because the line connecting the path node at any time and the search center remains perpendicular to the forward direction of the robot at that time.

[0043] As another specific implementation of Example 2, when the robot posture to be calculated is an angle of direction, the method for obtaining the posture of the robot at the time to be measured based on the change in the time weight of the robot posture within the time interval between two adjacent moments includes:

[0044] The robot sets the angle between the first forward direction and the baseline as the robot's first direction angle; the robot's first direction angle is the robot's direction angle at the first moment; the robot also sets the angle between the second forward direction and the baseline as the robot's second direction angle; the robot's second direction angle is the robot's direction angle at the second moment. The robot's direction angle is used to represent the angular characteristics of the robot's forward direction at a path node. It belongs to the robot's navigation direction carried by a path node and can be the angle relative to one of the coordinate axes of the map coordinate system or the axis of one of the coordinate axes of the map coordinate system, so that the direction angle and its angle are adaptable to different types of map marking methods, where the map is constructed by the robot and is used to mark path nodes.

[0045] On this basis, the robot calculates the difference between the angle of the second direction angle and the angle of the first direction angle, and sets the difference as the total incremental value of the direction angle, which can be expressed as the cumulative angle information of the robot's forward direction deflected in the time interval between the two adjacent moments; then the product of the total incremental value of the direction angle and the time change ratio is set as the effective angle change of the robot's direction angle; specifically, the robot will set the ratio of the time difference to be measured to the total time interval as the time change ratio, which is used to express the weight of the deflection angle change of the robot's forward direction at the moment to be measured relative to the first moment within the total incremental value of the direction angle, and then multiply the total incremental value of the direction angle by the time change ratio to obtain the effective angle change of the robot's direction angle, which is the predicted angle change of the direction angle in the process of the robot moving from the first moment to the moment to be measured, that is, the deflection angle change of the robot's forward direction. Then, the sum of the length of the first direction angle and the effective angle change of the robot's direction angle is set as the angle of the robot's direction angle at the time to be measured, which is used to represent the angle of the direction angle of the robot at the path node corresponding to the time to be measured, specifically, the angle formed by the robot's forward direction at the time to be measured relative to the baseline. Figure 1 In FIG, position point P3 is the position point predicted at the time to be measured, and the direction of the arrow at position point P3 is the forward direction of the robot corresponding to the direction angle calculated by the above method.

[0046] As another specific implementation of Example 2, when the robot posture to be calculated is a rotation angle, the method for obtaining the robot posture at the time to be measured based on the change in the time weight of the robot posture within the time interval between two adjacent moments includes:

[0047] When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; in the first preset straight line, the robot sets the ray pointing from the search center to the first path node as the first ray; in the second preset straight line, the robot sets the ray pointing from the search center to the second path node as the second ray; then the angle between the first ray and the second ray is set as the preset rotation angle, corresponding to Figure 1 In the example, the intersection of the second preset straight line OP2 and the first preset straight line OP1 is set as the search center O, the ray from the search center O to the first path node P1 is set as the first ray OP1, the ray from the search center O to the second path node P2 is set as the second ray OP2, and the angle between the first ray OP1 and the second ray OP2 is set as the preset rotation angle P1OP2. The rotation angle of the robot at the path node corresponding to the time to be measured is the angle formed by the ray from the search center to the path node with respect to the first ray.

[0048] On this basis, the robot sets the product of the preset rotation angle and the time change ratio as the angle of the robot's rotation angle at the time to be measured, which is used to represent the angle of the robot's rotation angle at the path node corresponding to the time to be measured, wherein the preset rotation angle represents the angle change of the robot's rotation angle between the two adjacent moments; specifically, the robot sets the ratio of the time difference to be measured to the total time interval as the time change ratio, which is used to represent the weight of the angle change of the robot's rotation angle at the time to be measured relative to the rotation angle at the first moment within the preset rotation angle, wherein the ratio of the angle between the path node of the robot at the time to be measured and the search center relative to the first ray to the angle of the preset rotation angle is equal to the ratio of the time taken by the robot to move from the first moment to the time to be measured to the total time interval; therefore, after multiplying the preset rotation angle by the time change ratio, the robot obtains the angle of the robot's rotation angle at the time to be measured, which is used as the deflection angle of the radial segment of the robot relative to the first ray during the process of the robot moving from the first moment to the time to be measured. Corresponding to Figure 1 In the figure, position point P3 is the position point predicted at the time to be measured, O is the search center, and line segment OP3 is a radial line segment determined at the time to be measured. The angle P1OP3 formed by line segment OP3 and the first ray OP1 is the rotation angle of the robot at position point P3.

[0049] In summary, Example 2 converts the posture information at the time to be measured according to the proportion of the time interval between the time to be measured and the starting time (the first time disclosed in the aforementioned technical solution) in the total time interval, and calculates the posture information of the path node at any time in the time interval between the first time and the second time between the first path node and the second path node. It can calculate the angle change and the length change under the premise that the calculation parameters do not affect each other, and supports the simultaneous acquisition of two posture information with different dimensions and non-interference. While ensuring the time continuity of the obtained posture information, it can also reduce the phenomenon of introducing the mechanical error of the posture information of one dimension into the posture information of another dimension, that is, overcome the interference of the error caused by the mechanical activity carried by the spatial coordinate distance information and the angle information of the path node, and realize the acquisition of predicted path nodes with less error, replacing the original discrete path composed of only two discrete points, and realizing the continuous processing of the discrete path composed of the aforementioned two discrete points.

[0050] In the aforementioned embodiment, the path node corresponding to the time to be tested is used to predict the position point to which the robot will move at the time to be tested in the process of the robot moving on the motion trajectory between the first path node and the path node in advance. The robot may have traversed this position point in advance, or may move to the area adjacent to this position point at the time to be tested.

[0051] In the aforementioned embodiment, each moment within the time interval between the second moment and the first moment corresponds to a path node. Starting from the first path node, the greater the moment to be measured used in the calculation, the closer the position of the path node calculated by the aforementioned embodiment is to the position of the second path node, including the length of the radial segment of the robot at the path node, the angle of the robot's direction angle at the path node, and the angle value of the robot's rotation angle at the path node. This facilitates counting and statistically predicting the number of path nodes and the order of inserting the predicted motion trajectory within the time interval between the second moment and the first moment, thereby forming a node information set of a traceable robot motion trajectory.

[0052] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for obtaining a robot's path nodes in a time-continuous manner, characterized in that: Before executing the time-continuous acquisition method, the robot obtains a path node at each of two adjacent moments in the movement process; the robot does not obtain a path node within the time interval between the two adjacent moments; The time-continuous acquisition method comprises: Obtaining the robot's posture at a time to be measured based on a change in the robot's posture between two adjacent moments, wherein the time to be measured is within a time interval between the two adjacent moments obtained in advance; The robot's posture includes the length of the robot's radial segment at the path node, the angle of the robot's orientation angle at the path node, and the angle value of the robot's rotation angle at the path node; The time continuity acquisition method further includes: setting two adjacent moments obtained in advance as the first moment and the second moment respectively; The method for obtaining the posture of the robot at the time to be measured based on the change of the posture of the robot between two adjacent moments is: According to the rate of change of the robot's posture between two adjacent moments, the posture of the robot at the time to be measured is obtained; The rate of change of the robot's posture between two adjacent moments includes: The length change rate of the robot's radial segment between the second moment and the first moment, the angular change rate of the robot's direction angle between the second moment and the first moment, and the angular change rate of the robot's rotation angle between the second moment and the first moment.

2. The time-continuous acquisition method according to claim 1, characterized in that: The first moment is less than the second moment, and the time difference between the second moment and the first moment is fixed; The time difference between the second moment and the first moment is set as the total time interval; the time difference between the time to be measured and the first moment is set as the time difference to be measured.

3. The time-continuous acquisition method according to claim 2, characterized in that: The robot sets the path node obtained at the first moment as the first path node, and the robot sets the path node obtained at the second moment as the second path node; The robot sets its forward direction at the first path node as the first forward direction, and then sets a straight line passing through the first path node and perpendicular to the first forward direction as a first preset straight line; The robot sets its forward direction at the second path node as the second forward direction, and then sets the straight line passing through the second path node and perpendicular to the second forward direction as the second preset straight line.

4. The time-continuous acquisition method according to claim 3, characterized in that: The method for obtaining the posture of the robot at the time to be measured based on the rate of change of the posture of the robot between two adjacent moments includes: Calculate the difference between the length of the second radial segment and the length of the first radial segment, and set the difference as the total incremental value of the radial segment; Then, the ratio of the total incremental value of the radial segment to the total time interval is set as the length change rate of the robot's radial segment between the two adjacent moments. Then, the time difference to be measured is multiplied by the length change rate of the robot's radial segment between the two adjacent moments. The obtained product is then set as the effective length change of the robot's radial segment. Then, the sum of the length of the first radial segment and the effective length change of the radial segment of the robot is set as the length of the radial segment of the robot at the time to be measured, which is used to represent the length of the radial segment of the robot at the path node corresponding to the time to be measured; When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; then the line segment connecting the search center and the first path node is set as the first radial line segment of the robot, and the line segment connecting the search center and the second path node is set as the second radial line segment of the robot; The first radial line segment of the robot is the radial line segment of the robot at the first moment, and the second radial line segment of the robot is the radial line segment of the robot at the second moment.

5. The time-continuous acquisition method according to claim 1, characterized in that: The method for obtaining the posture of the robot at the time to be measured based on the rate of change of the posture of the robot between two adjacent moments includes: Calculate the difference between the second direction angle and the first direction angle, and set the difference as the total incremental value of the direction angle; Then, the ratio of the total increment value of the direction angle to the total time interval is set as the angle change rate of the robot's direction angle between the two adjacent moments, and then the time difference to be measured is multiplied by the angle change rate, and the obtained product is set as the effective angle change of the robot's direction angle; Then, the sum of the length of the first direction angle and the effective angle change of the robot's direction angle is set as the angle of the robot's direction angle at the time to be measured, which is used to represent the angle of the robot's direction angle at the path node corresponding to the time to be measured; The angle between the first forward direction and the reference line is set as the first direction angle of the robot; the first direction angle of the robot is the direction angle of the robot at the first moment; The angle formed by the second forward direction and the reference line is set as the second direction angle of the robot; the second direction angle of the robot is the direction angle of the robot at the second moment.

6. The time-continuous acquisition method according to claim 3, characterized in that: The method for obtaining the posture of the robot at the time to be measured based on the rate of change of the posture of the robot between two adjacent moments includes: The ratio of the preset rotation angle to the total time interval is set as the angle change rate of the robot's rotation angle between the two adjacent moments, the time difference to be measured is multiplied by the angle change rate, and the obtained product is set as the angle of the robot's rotation angle at the moment to be measured, which is used to represent the angle of the robot's rotation angle at the path node corresponding to the moment to be measured; When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; In a first preset straight line, setting the ray from the search center to the first path node as a first ray; In the second preset straight line, the ray from the search center to the second path node is set as the first ray; Then, the angle formed by the first ray and the second ray is set as a preset rotation angle; The rotation angle of the robot at the path node corresponding to the time to be measured is the angle formed by the ray from the search center to the path node relative to the first ray.

7. The time-continuous acquisition method according to claim 3, characterized in that: The method for obtaining the posture of the robot at the time to be measured based on the change of the posture of the robot between two adjacent moments is: According to the time weight change of the robot's posture in the time interval between two adjacent moments, the posture of the robot at the time to be measured is obtained; The ratio of the time difference to be measured to the total time interval is used to represent the time weight change of the robot's posture within the time interval between the two adjacent moments; The ratio of the time difference to be measured to the total time interval is set as the time change ratio.

8. The time-continuous acquisition method according to claim 7, characterized in that: The method for obtaining the posture of the robot at the time to be measured according to the change of the time weight of the posture of the robot in the time interval between two adjacent moments includes: Calculate the difference between the length of the second radial segment and the length of the first radial segment, and set the difference as the total incremental value of the radial segment; Then, the product of the total incremental value of the radial segment and the time change ratio is set as the effective length change of the radial segment of the robot; Then, the sum of the length of the first radial segment and the effective length change of the radial segment of the robot is set as the length of the radial segment of the robot at the time to be measured, which is used to represent the length of the radial segment of the robot at the path node corresponding to the time to be measured; When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; then the line segment connecting the search center and the first path node is set as the first radial line segment of the robot, and the line segment connecting the search center and the second path node is set as the second radial line segment of the robot; The first radial line segment of the robot is the radial line segment of the robot at the first moment, and the second radial line segment of the robot is the radial line segment of the robot at the second moment.

9. The time-continuous acquisition method according to claim 7, characterized in that: The method for obtaining the posture of the robot at the time to be measured according to the change of the time weight of the posture of the robot in the time interval between two adjacent moments includes: Calculate the difference between the second direction angle and the first direction angle, and set the difference as the total incremental value of the direction angle; Then, the product of the total increment value of the direction angle and the time change ratio is set as the effective angle change of the robot's direction angle; Then, the sum of the length of the first direction angle and the effective angle change of the robot's direction angle is set as the angle of the robot's direction angle at the time to be measured, which is used to represent the angle of the robot's direction angle at the path node corresponding to the time to be measured; The angle between the first forward direction and the reference line is set as the first direction angle of the robot; the first direction angle of the robot is the direction angle of the robot at the first moment; The angle formed by the second forward direction and the reference line is set as the second direction angle of the robot; the second direction angle of the robot is the direction angle of the robot at the second moment.

10. The time-continuous acquisition method according to claim 7, characterized in that: The method for obtaining the posture of the robot at the time to be measured according to the change of the time weight of the posture of the robot in the time interval between two adjacent moments includes: The product of the preset rotation angle and the time change ratio is set as the rotation angle of the robot at the time to be measured, which is used to represent the rotation angle of the robot at the path node corresponding to the time to be measured; When the first preset straight line intersects the second preset straight line, the intersection of the second preset straight line and the first preset straight line is set as the search center; In a first preset straight line, setting the ray from the search center to the first path node as a first ray; In the second preset straight line, the ray from the search center to the second path node is set as the first ray; Then, the angle formed by the first ray and the second ray is set as a preset rotation angle.

11. The time-continuous acquisition method according to claim 1 or 7, characterized in that: Any moment within the time interval between the second moment and the first moment corresponds to a path node. The larger the measured moment is, the closer the calculated posture of the path node is to the posture of the second path node.

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