A path planning method for wind tunnel models based on multiple motion mechanisms

Abstract

A wind tunnel model path planning method based on multiple motion mechanisms is used to design the running paths of aircraft models and external attachment models in a grid force measurement test of multiple motion mechanisms, so as to enable the aircraft models and external attachment models to complete all grid points efficiently and safely. The method belongs to the technical field of grid force measurement wind tunnel test, and comprises: (1) establishing motion simulation models of motion mechanisms, test models and wind tunnels; (2) designing multiple paths with different motion sequences according to the distribution of test grid points of each test model; (3) setting the motion mode of the motion mechanism to move simultaneously at the maximum running speed, and then simulating the multiple paths, selecting the first two paths A and B with the shortest time as candidate paths, assuming that path A is the path with the shortest time; (4) performing collision detection simulation on paths A and B to determine the final test implementation path.

Description

Technical Field

[0001] The present invention relates to a wind tunnel model path planning method based on a multi-motion mechanism, which is used to design the running paths of an aircraft model and an external attachment model in a multi-motion mechanism grid force measurement test, so as to enable the aircraft model and the external attachment model to complete all grid points efficiently and safely, and belongs to the technical field of grid force measurement wind tunnel tests. Background Art

[0002] At present, there are situations in which multiple motion mechanisms and multiple test models move in coordination in grid force measurement tests. For example, an angle of attack-dual-axis mechanism is used to support and control an aircraft model, and a six-degree-of-freedom motion mechanism is used to support and control an external attachment model, so as to coordinately complete the position control and measurement of grid points in the multi-body separation interference space.

[0003] The grid points of the grid force test include multiple displacement and attitude variables, including the aircraft's pitch angle, yaw angle, roll angle, X displacement of the external load relative to the aircraft, Y displacement of the external load relative to the aircraft, Z displacement of the external load relative to the aircraft, pitch angle of the external load relative to the aircraft, yaw angle of the external load relative to the aircraft, and roll angle of the external load relative to the aircraft. With so many variables, there can be many paths in the grid point space that can complete the movement of all grid points. Therefore, it is necessary to select the path with the highest test efficiency and no collision from all these paths. The time required to walk through all grid points is affected by the operation sequence and operation speed of multiple mechanisms; whether collisions will occur in the operation path, that is, whether collisions will occur at the grid point positions and between grid points during the walking process (including whether collisions will occur between mechanisms, mechanisms and models, models and models, mechanisms and wind tunnels, and models and wind tunnels). The prediction of collisions involves multiple factors such as the relationship between the forward and inverse solutions of the mechanisms, the form of the speed operation curve of the mechanisms, the operation sequence of the mechanisms, the contours of the mechanisms and models, and the positions of the mechanisms and models in the wind tunnel. Therefore, it is necessary to establish an operation model of the wind tunnel, mechanisms, and models, and to detect the collisions of the mechanisms, models, and wind tunnels.

[0004] Currently, the path design of grid force measurement tests often fails to consider test efficiency and path collision situations. Before the establishment of mechanisms, models, and wind tunnel motion simulation models, collision detection can only be performed on a few feature points. As the number of mechanisms increases and coordinated motion occurs, comprehensive collision detection is difficult to achieve. Therefore, the designed path is often tried before the wind tunnel test. This method is relatively blind and cannot find the test implementation path. If a collision occurs during the trial, there is a risk of damage to the equipment. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and propose a practical and effective method for designing a grid force measurement test path to achieve efficient and safe completion of the test content.

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

[0007] A wind tunnel model path planning method based on multiple motion mechanisms includes the following steps:

[0008] (1) Establish motion simulation models of motion mechanisms, test models, and wind tunnels;

[0009] (2) Design multiple paths with different motion sequences based on the test grid point distribution of each test model;

[0010] (3) The motion mode of the motion mechanism is set to move simultaneously at the maximum operating speed, and then multiple paths are simulated, and the paths A and B with the shortest time are selected as candidate paths. It is assumed that path A is the path with the shortest time;

[0011] (4) Perform collision detection simulation on path A and path B and process them as follows:

[0012] (a) If no collision occurs on path A, path A is selected as the test implementation path;

[0013] (b) If a collision occurs on path A and no collision occurs on path B, adjust the running sequence and running speed of the motion mechanism on path A. If no collision occurs on path A after adjustment, compare it with path B and select the path with the shortest time as the test implementation path. If a collision still occurs on path A after adjustment, select path B as the test implementation path.

[0014] (c) If both path A and path B collide, the operation sequence and operation speed of the two motion mechanisms are adjusted respectively, and the path that still cannot avoid collision is eliminated. The candidate path is re-selected based on the principle of minimum time from the paths that did not collide and the remaining paths in step (3), and the process goes to step (4).

[0015] A wind tunnel model path planning device based on multiple motion mechanisms, comprising:

[0016] The first module is used to establish motion simulation models of motion mechanisms, test models and wind tunnels;

[0017] In the second module, multiple paths with different motion sequences are designed based on the test grid point distribution of each test model;

[0018] In the third module, the motion mechanism is set to move simultaneously at the maximum speed. Multiple paths are then simulated, and the paths A and B with the shortest time are selected as candidate paths. Path A is assumed to be the shortest path.

[0019] The fourth module performs collision detection simulation on path A and path B and processes them as follows:

[0020] (a) If no collision occurs on path A, path A is selected as the test implementation path;

[0021] (b) If a collision occurs on path A and no collision occurs on path B, adjust the running sequence and running speed of the motion mechanism on path A. If no collision occurs on path A after adjustment, compare it with path B and select the path with the shortest time as the test implementation path. If a collision still occurs on path A after adjustment, select path B as the test implementation path.

[0022] (c) If both path A and path B collide, the operation sequence and speed of their motion mechanisms are adjusted respectively, and the path that still cannot avoid collision is eliminated. The candidate path is reselected based on the principle of minimum time from the paths that did not collide and the remaining paths of the third module, and the collision detection simulation is repeated.

[0023] In one embodiment of the present invention, the plurality of mechanisms include a set of three-degree-of-freedom motion mechanisms and a set of six-degree-of-freedom motion mechanisms operating simultaneously in the wind tunnel.

[0024] In one embodiment of the present invention, a motion simulation model of multiple mechanisms, multiple models, and a wind tunnel needs to consider the degree of freedom constraints of the connections between the mechanisms, models, and wind tunnels.

[0025] In one embodiment of the present invention, the motion simulation model of multiple mechanisms, multiple models, and a wind tunnel needs to consider the realistic simulation of the operating speed curve of the driving components of each mechanism.

[0026] In one embodiment of the present invention, the motion simulation model of multiple mechanisms, multiple models and wind tunnels needs to consider whether collisions will occur between the various components of the mechanism itself, between mechanisms, between mechanisms and models, between models, between mechanisms and wind tunnels, and between models and wind tunnels. If a collision occurs in any of these situations, the collision detection result is determined to be "collision", otherwise the collision detection result is determined to be "safe".

[0027] In one embodiment of the present invention, when selecting a test implementation path from among the candidate paths, the following situations are considered:

[0028] (a) When simulating the two paths with the shortest time in both simultaneous motion and maximum speed modes, if no collision occurs on the path with the shortest time, the path with the shortest time will be selected as the test implementation path;

[0029] (b) When simulating the two paths with the shortest time in both simultaneous motion and maximum speed modes, the path with the shortest time collided, while the path with the second shortest time did not collide. The following situations can be considered:

[0030] (b.1) Improve the mechanism operation mode of the path with the shortest maximum speed, including changing the operation sequence and speed of each mechanism to prevent collisions. Compare this path with the path with the second shortest maximum speed. Select the path with the shortest time as the experimental path and select the corresponding mechanism operation mode as the mechanism operation mode during the test.

[0031] (b.2) If improving the operating mode of the mechanism with the shortest maximum speed time, including changing the operating sequence and speed of each mechanism, fails to prevent collisions, then the path with the second shortest maximum speed time will be selected as the experimental path;

[0032] (c) Among the candidate paths, if collisions occur when simulating the two paths with the shortest time in both simultaneous motion and maximum speed modes, the operation sequence and speed of the two motion mechanisms are adjusted respectively, and the paths that still cannot avoid collisions are eliminated. The candidate paths are reselected based on the principle of shortest time from the paths that did not collide and the remaining paths, and the test implementation path is reselected based on situations (a) and (b).

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) Conventional grid force measurement tests do not consider the contradiction between test efficiency and test collision conditions when designing the path of grid points. The method of the present invention can realize the calculation and prediction of the test efficiency and collision conditions of the path in the grid force measurement test, and select the test implementation path according to the path planning method to achieve the grid force measurement test to efficiently and safely complete the measurement of all grid points, taking into account both safety and efficiency.

[0035] (2) Currently, grid force measurement tests only perform collision detection on feature points, and the detection results cannot cover all moving objects in the wind tunnel. The present invention establishes a three-dimensional model of all objects in the wind tunnel and their kinematic models, strictly simulates the driving speed mode of the moving objects, and achieves accurate simulation of the position change of the objects in the wind tunnel, thereby more accurately predicting the collision situation of all moving objects in the wind tunnel during simultaneous movement, providing a safer protection technology for multi-mechanism and multi-model wind tunnel tests.

[0036] (3) Compared with the conventional method of judging whether a collision occurs in the selected grid path through trial and error, the present invention establishes a three-dimensional model and a kinematic simulation model of multiple mechanisms and models, which can accurately simulate the running trajectories of multiple mechanisms and models in the wind tunnel in a virtual environment, thereby realizing collision detection of multiple mechanisms and models in a virtual environment, avoiding equipment losses caused by trial and error collisions, improving the safety of the test system, and also improving the iterative efficiency of test grid path preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of the steps of the wind tunnel model path planning method of the present invention;

[0038] Figure 2 Schematic diagram of a dual-model wind tunnel test system with dual mechanisms (angle of attack-dual-axis mechanism, six-degree-of-freedom mechanism);

[0039] Figure 3 is the driving speed curve of the motion mechanism, Figure 3 a is the attack angle-driving speed curve of the dual-axis mechanism, Figure 3 b is the driving speed curve of the 6-PTRT spindle;

[0040] Figure 4 Schematic diagram of grid point distribution for dual-model test;

[0041] Figure 5 is a schematic diagram of the test grid point path, Figure 5 a is grid path 1, Figure 5 b is grid path 2. DETAILED DESCRIPTION

[0042] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0043] A path planning method for a wind tunnel model based on multiple motion mechanisms, such as Figure 1 Shown, including:

[0044] (1) Establish a motion simulation model of the motion mechanism, test model, and wind tunnel, and detect whether there will be a collision between the motion mechanism, test model, and wind tunnel based on the operating positions of the motion mechanism, test model, and wind tunnel;

[0045] like Figure 2 As shown, a set of three-degree-of-freedom motion mechanisms and a set of six-degree-of-freedom motion mechanisms are shown. The three-degree-of-freedom motion mechanism is a dual-axis mechanism, and the six-degree-of-freedom motion mechanism is a 6-PTRT mechanism. The model includes a first-stage aircraft model and a second-stage aircraft model. The established motion simulation model considers the connection degree-of-freedom constraints between the dual-axis mechanism, the 6-PTRT mechanism, the first-stage aircraft model, the second-stage aircraft model, and the wind tunnel.

[0046] In the embodiment, the driving components of the angle-of-attack-dual-axis mechanism include an angle-of-attack axis drive, a main axis drive, and a tail axis drive. The maximum output rotation speed of the three drives is 16.615° / s, the speed curve is a trapezoidal curve, the acceleration time is 0.5s, and the deceleration time is 0.5s. Figure 3 As shown in a;

[0047] In the embodiment, the 6-PTRT uses the axis with the largest running amount as the main axis of the six-axis synchronous motion (simultaneous start and stop), the maximum running speed of the main axis is 100mm / s, and the acceleration value of the acceleration and deceleration section is 1000mm / s 2 , the speed curve is a trapezoidal curve, such as Figure 3 As shown in b, the acceleration value of the acceleration and deceleration section is 1000 mm / s 2 , acceleration time 0.1s, deceleration time 0.1s.

[0048] The maximum operating speed and acceleration values ​​of other axes are converted according to the ratio w of the operating amount to the maximum operating amount. For example, the operating amount S of axes 1 to 6 is i If they are 1000, 900, 800, 700, 600 and 500 respectively, let axis 1# be the main axis and the other axes be slave axes. The maximum operating speed and acceleration values ​​of each axis are shown in Table 1.

[0049] Table 1 Running speed and acceleration of each axis

[0050]

[0051] In the embodiment, if a collision occurs between the angle of attack-dual-axis mechanism, the 6-PTRT mechanism, the first-level aircraft model, the second-level aircraft model, and the wind tunnel, the collision detection result is determined to be "collision", otherwise the collision detection result is determined to be "safe".

[0052] (2) Design multiple paths based on the multiple point positions in the wind tunnel of multiple models in the wind tunnel test.

[0053] (3) According to the simultaneous motion and maximum operating speed modes of each motion mechanism, multiple paths are simulated, and the paths with the shortest time are selected as candidate paths.

[0054] like Figure 4 As shown, in the embodiment, the pitch angle range in the grid points of the first-level aircraft model is The displacement X range in the grid point of the secondary aircraft is The displacement Y range is The displacement Z range is Based on these grid points, the following two grid point paths are designed.

[0055] Path 1: If Figure 5 As shown in a, it is divided into 4 levels. The first level sequence is the pitch angle of the first-level aircraft model. The second-level sequence is the displacement x of the second-level aircraft model 2 , the third level sequence is the displacement z of the second level aircraft model 2 , the fourth level sequence is the displacement y of the second level aircraft model 2; Traverse all grid points step by step in the order of "4th level sequence - 3rd level sequence - 2nd level sequence - 1st level sequence";

[0056] Path 2: If Figure 5 As shown in b, it is divided into 4 levels. The first level sequence is the pitch angle of the first-level aircraft model. The second-level sequence is the displacement x of the second-level aircraft model 2 , the third level sequence is the displacement y of the second level aircraft model 2 , the fourth level sequence is the displacement z of the second level aircraft model 2 ; Traverse all grid points step by step in the order of "4th level sequence - 3rd level sequence - 2nd level sequence - 1st level sequence";

[0057] Using the simultaneous motion and maximum speed modes of all motion mechanisms, path 1 is the shortest path, and path 2 is the second shortest path;

[0058] (4) Perform collision detection simulation on the two paths with the shortest time, and select the path with the shortest time and no collision.

[0059] In the embodiment, a collision detection simulation is performed on path 1 and path 2, and path 1 collides while path 2 does not. The collision condition of path 1 is: Sequence, first-level aircraft model from Towards Sports, secondary aircraft models from Towards During this movement, the first-stage aircraft model collides with the second-stage aircraft model. By reducing the speed of the first-stage aircraft model, path 1 can prevent collisions. Comparing the time taken for path 1 and path 2, which reduce the speed of the first-stage aircraft model, path 1 takes less time than path 2. Finally, path 1, which reduces the speed of the first-stage aircraft model, is selected as the experimental implementation path.

[0060] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

[0061] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solutions of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the scope of protection of the technical solutions of the present invention.

Claims

1. A wind tunnel model path planning method based on multiple motion mechanisms, characterized in that: include: (1) Establish motion simulation models of motion mechanisms, test models, and wind tunnels; (2) Design multiple paths with different motion sequences based on the test grid point distribution of each test model; (3) The motion mode of the motion mechanism is set to move simultaneously at the maximum operating speed, and then multiple paths are simulated, and the paths A and B with the shortest time are selected as candidate paths. It is assumed that path A is the path with the shortest time; (4) Perform collision detection simulation on path A and path B and process them as follows: (a) If no collision occurs on path A, path A is selected as the test implementation path; (b) If a collision occurs on path A and no collision occurs on path B, adjust the running sequence and running speed of the motion mechanism on path A. If no collision occurs on path A after adjustment, compare it with path B and select the path with the shortest time as the test implementation path. If a collision still occurs on path A after adjustment, select path B as the test implementation path. (c) If both path A and path B collide, the operation sequence and operation speed of the two motion mechanisms are adjusted respectively, and the path that still cannot avoid collision is eliminated. The candidate path is re-selected based on the principle of minimum time from the paths that did not collide and the remaining paths in step (3), and the process goes to step (4).

2. The wind tunnel model path planning method according to claim 1, characterized in that: The motion mechanism includes a set of three-degree-of-freedom motion mechanism and a set of six-degree-of-freedom motion mechanism running simultaneously in the wind tunnel.

3. The wind tunnel model path planning method according to claim 1, characterized in that: To establish the motion simulation model of the motion mechanism, test model and wind tunnel, it is necessary to consider the degree of freedom constraints of the connections between the motion mechanism, test model and wind tunnel.

4. The wind tunnel model path planning method according to claim 1, characterized in that: To establish motion simulation models of motion mechanisms, test models and wind tunnels, it is necessary to consider the realistic simulation of the operating speed curves of the driving components of each motion mechanism.

5. The wind tunnel model path planning method according to claim 1, characterized in that: Consider whether collisions may occur between the components of the motion mechanism itself, between the motion mechanism and the motion mechanism, between the motion mechanism and the test model, between the test models, between the motion mechanism and the wind tunnel, and between the test model and the wind tunnel. If any of these situations occurs, the collision detection result is judged as "collision". Otherwise, the collision detection result is judged as "safe".

6. A wind tunnel model path planning device based on multiple motion mechanisms, characterized in that: include: The first module is used to establish motion simulation models of motion mechanisms, test models and wind tunnels; In the second module, multiple paths with different motion sequences are designed based on the test grid point distribution of each test model; In the third module, the motion mechanism is set to move simultaneously at the maximum speed. Multiple paths are then simulated, and the paths A and B with the shortest time are selected as candidate paths. Path A is assumed to be the shortest path. The fourth module performs collision detection simulation on path A and path B and processes them as follows: (a) If no collision occurs on path A, path A is selected as the test implementation path; (b) If a collision occurs on path A and no collision occurs on path B, adjust the running sequence and running speed of the motion mechanism on path A. If no collision occurs on path A after adjustment, compare it with path B and select the path with the shortest time as the test implementation path. If a collision still occurs on path A after adjustment, select path B as the test implementation path. (c) If both path A and path B collide, the operation sequence and speed of their motion mechanisms are adjusted respectively, and the path that still cannot avoid collision is eliminated. The candidate path is reselected based on the principle of minimum time from the paths that did not collide and the remaining paths of the third module, and the collision detection simulation is repeated.

7. The wind tunnel model path planning device according to claim 6, characterized in that: The motion mechanism includes a set of three-degree-of-freedom motion mechanism and a set of six-degree-of-freedom motion mechanism running simultaneously in the wind tunnel.

8. The wind tunnel model path planning device according to claim 6, characterized in that: To establish the motion simulation model of the motion mechanism, test model and wind tunnel, it is necessary to consider the degree of freedom constraints of the connections between the motion mechanism, test model and wind tunnel.

9. The wind tunnel model path planning device according to claim 6, characterized in that: To establish motion simulation models of motion mechanisms, test models and wind tunnels, it is necessary to consider the realistic simulation of the operating speed curves of the driving components of each motion mechanism.

10. The wind tunnel model path planning device according to claim 6, characterized in that: Consider whether collisions may occur between the components of the motion mechanism itself, between the motion mechanism and the motion mechanism, between the motion mechanism and the test model, between the test models, between the motion mechanism and the wind tunnel, and between the test model and the wind tunnel. If any of these situations occurs, the collision detection result is judged as "collision". Otherwise, the collision detection result is judged as "safe".

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