A lunar rover wheel drive system ultra-low temperature impact adaptability test verification method

Abstract

The application discloses a lunar vehicle wheel driving system super-low-temperature impact adaptability test verification method, which comprises the following steps: installing a to-be-detected wheel and a driving mechanism on a test table, adjusting the load on the wheel, and setting the rotating speed of the driving mechanism; stopping the wheel after driving the wheel into a heating area of the test table, until the temperature of multiple positions on the wheel and the driving mechanism is higher than a preset temperature; driving the wheel out of the heating area; stopping the wheel after driving the wheel into a refrigeration area of the test table, rapidly cooling the wheel, and driving the wheel out of the refrigeration area after a preset calibration cooling time; continuing to drive the wheel into the heating area, starting a second cycle, and performing a load capacity test on the wheel and a performance test on the driving mechanism after a preset cycle number is reached. The application can simulate the actual working condition of the wheel driving system through temperature rising and rapid cooling, and can test the mechanical performance and structural performance of the wheel driving system under long-distance and multiple alternating temperature working conditions.

Description

Technical Field

[0001] This invention belongs to the field of lunar rover testing, and in particular relates to a method for verifying the ultra-low temperature shock adaptability of a lunar wheel drive system. Background Technology

[0002] In the high-latitude, sunlit areas of the lunar south pole, the ambient temperature is below 100K, while the temperature at the bottom of the shadowed craters can drop to as low as 40K (-233℃). When the lunar rover is exploring the south pole region, the solar altitude angle is close to 0°, and obstructions from rocks, lunar ridges, and small craters cause the rover's movement system to rapidly transition from sunlit to shadowed areas. my country's lunar rover plans to explore deep into the bottom of permanently shadowed craters. When the rover moves from sunlit areas into permanently shadowed areas, its wheel drive system will face severe temperature shocks (from ambient temperature of 25℃ to -233℃).

[0003] To verify the reliability and stability of the lunar wheel drive system under cryogenic shock conditions, including the wheel structure, drive mechanism, and connections, it is necessary to conduct cryogenic shock verification tests on the wheel drive system during lunar surface exploration. This involves simulating the lunar surface temperature environment on Earth to test the wheel drive performance during operation, providing a reference for wheel drive material selection, structural design, transmission design, connections, and exploration path planning. Summary of the Invention

[0004] The technical objective of this invention is to provide a method for testing and verifying the ultra-low temperature shock adaptability of a lunar wheel drive system, so as to solve the problem of ultra-low temperature shock adaptability of the lunar wheel drive system during its operation in the polar regions of the moon.

[0005] To solve the above problems, the technical solution of the present invention is as follows: A method for verifying the cryogenic shock adaptability of a lunar wheel drive system includes the following steps: The wheel to be tested and the drive mechanism driving the wheel to be tested are installed on the test bench. The load on the wheel to be tested is adjusted and the speed of the drive mechanism is set. After driving the wheel under test into the heating zone of the test bench, stop until the temperature of multiple parts of the wheel under test and the drive mechanism are higher than the preset temperature, then drive it out of the heating zone. After driving the wheel to be tested into the cooling zone of the test bench, stop and rapidly cool the wheel. After the cooling time reaches the preset calibrated cooling time, drive it out of the cooling zone. The wheel under test is driven into the heating zone to begin the second cycle. After the number of cycles reaches the preset number, the load-bearing capacity of the wheel under test is tested, and the performance of the drive mechanism is tested.

[0006] More preferably, before installing the wheel to be tested and the drive mechanism that drives the wheel to be tested on the test bench, it is necessary to conduct a load-bearing capacity test on the wheel to be tested and a performance test on the drive mechanism, so as to compare the load-bearing capacity of the wheel to be tested and the performance of the drive mechanism after the ultra-low temperature impact adaptability test.

[0007] More preferably, before and after the load-bearing capacity test, the condition of the wheel to be tested must be checked and recorded, including: the connection status of the wheel surface, hub, and punctures, as well as any deformation or damage.

[0008] The performance of the drive mechanism is tested, and the drive voltage, current and speed of the drive mechanism are recorded.

[0009] More preferably, before installing the wheel to be tested and the drive mechanism that drives the wheel to be tested on the test bench, it is also necessary to obtain the calibration cooling time. In the cooling zone, the wheel to be tested and the drive mechanism are cooled from room temperature to the preset minimum temperature, and the time required is measured. The average value of the multiple measurements is taken as the preset calibration cooling time.

[0010] More preferably, during the cyclic test, after the number of cycles reaches the preset number of tests, the wheel condition is checked and recorded, including the wheel, drive, connection condition, mechanism operation condition, wheel deformation or damage condition.

[0011] The test bench has a ring structure, which is divided into a heating zone, a transition zone and a cooling zone. The cooling zone is equipped with a liquid helium tank, and only the part of the wheel under test below the axle is immersed in liquid helium to achieve cooling. The transition zone is covered with cotton and linen pads to absorb the residual liquid helium brought out by the wheel under test from the liquid helium tank.

[0012] More preferably, it also includes an obstacle testing step: setting up obstacles near the entrance of the refrigeration zone to test the obstacle-crossing ability and structural strength of the wheel under test under the large temperature difference condition of driving from high temperature to low temperature zone; or setting up obstacles near the exit of the refrigeration zone, and after the wheel under test stays in the refrigeration zone until the temperature of each part reaches the test requirements, testing the obstacle-crossing ability and structural strength under low temperature condition.

[0013] Because the present invention adopts the above technical solution, it has the following advantages and positive effects compared with the prior art: The temperature shock adaptability test of the wheel drive system designed in this invention fully considers the driving requirements of the lunar rover and the temperature difference on the lunar surface. By heating and rapidly cooling, it simulates the actual working conditions of the wheel drive system and can test the mechanical and structural performance of the wheel drive system under long-distance and multiple alternating temperature conditions. Attached Figure Description

[0014] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0015] Figure 1 This is a schematic diagram of the layout of the test bench of the present invention; Figure 2 This is a cross-sectional unfolded schematic diagram of the test bench of the present invention; Figure 3 This is a flowchart of a method for verifying the cryogenic shock adaptability of a lunar wheel drive system according to the present invention. Detailed Implementation

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0017] To keep the drawings concise, only the parts relevant to the invention are shown schematically in each figure, and they do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of components with the same structure or function is shown schematically, or only one is labeled. In this document, "one" can mean not only "only one" but also "more than one".

[0018] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a method for verifying the cryogenic shock adaptability of a lunar wheel drive system according to the present invention. The advantages and features of the present invention will become clearer from the following description and claims.

[0019] Example See Figures 1 to 3 This embodiment provides a method for verifying the cryogenic shock adaptability of a lunar wheel drive system. The implementation of this method depends on the test rig used in the test, specifically as follows: Figure 1 and Figure 2 As shown. Specifically, the test bench has a ring structure, which is divided into a heating zone, a transition zone, and a cooling zone. The heating zone is used to simulate the high temperature conditions of the wheel and can be heated electrically; the cooling zone is equipped with a liquid helium tank, which is filled with liquid helium and the liquid helium level in the tank is kept constant; the transition zone is lined with cotton and linen pads to absorb residual liquid helium brought out by the wheel under test from the liquid helium tank.

[0020] like Figure 2As shown, considering the requirements for wheel movement, the test system includes the motor, transmission, and corresponding control system necessary for wheel drive and control. Therefore, the wheel cannot be completely immersed in the liquid helium tank; only the structure below the wheel axle is immersed in liquid helium. Since the wheel and drive mechanism are made of metal, which has good thermal conductivity, the temperature of each part of the wheel drive system can be ensured to meet the test requirements by measuring the residence time in liquid helium. To monitor the temperature of each part, multiple temperature sensors are installed at various points on the wheel surface, wheel hub, and drive mechanism.

[0021] like Figure 3 As shown, this embodiment specifically includes the following steps: First, before conducting the temperature shock adaptability test, it is necessary to perform load-bearing capacity tests on the wheels under test and performance tests on the drive mechanism to compare the load-bearing capacity of the wheels under test and the performance of the drive mechanism after the ultra-low temperature shock adaptability test. Specifically: Before the test, check and record the condition of the wheel, including the wheel surface, hub, and chock connection, and whether there is any deformation or damage. After the inspection, place the wheel on the testing machine to test the wheel's forward load-bearing capacity and lateral tensile strength, and record the data. After the load-bearing capacity test, check and record the condition of the wheel again, including the wheel surface, hub, and chock connection, and whether there is any deformation or damage. Perform performance tests on the drive mechanism, and record the drive voltage, current, and speed.

[0022] Secondly, before the formal temperature shock test, the cooling time of the wheel drive system was calibrated within the test apparatus. The time required, t, to lower the wheel drive system from room temperature (above 25°C) to the minimum temperature (below -233°C) was determined. During measurement, liquid helium was filled into the cooling zone, and wheels at a temperature not lower than 25°C were placed in the cooling tank. Temperature sensors were installed at multiple locations on the wheel surface, hub, and drive mechanism to measure the temperature at different locations in real time until the main temperature measurement points dropped to -233°C. The time interval from when the wheel drive system entered the cooling zone to when the temperature met the minimum requirement was calculated as the cooling time, t. The test was repeated three times, and the average value was taken to obtain the calibrated cooling time.

[0023] Next, the wheel to be tested and the drive mechanism driving the wheel are installed on the test bench. The load on the wheel to be tested is adjusted, and the rotational speed of the drive mechanism is set. The wheel drive system is started, and the wheel to be tested is driven into the heating zone of the test bench and then stopped. Heating begins until the temperature of multiple parts of the wheel to be tested and the drive mechanism are higher than the preset temperature (25°C). Then, the drive is started and the wheel is driven out of the heating zone. The wheel to be tested is driven into the cooling zone of the test bench and then stopped. Liquid nitrogen in the cooling zone rapidly cools the wheel. After the cooling time reaches the preset calibrated cooling time, the drive is started and the wheel is driven out of the cooling zone, completing one cycle of high and low temperature test. The wheel continues to drive into the heating zone to start the second cycle. After the number of cycles reaches the preset number of cycles (which should be no less than 200 times, and can be adjusted according to actual needs), the cycle is stopped. More preferably, during the cyclic test, when the number of cycles reaches the preset number of tests (which can be 20 times, and can be adjusted according to actual needs), the wheel status is checked and recorded, including the wheel, drive, connection status, mechanism operation status, and wheel deformation or damage. Finally, after completing the low-temperature adaptability test of the wheels, the wheel load-bearing capacity test and the drive mechanism performance test were conducted again. See Figure 2 Furthermore, during the low-temperature adaptability test of the wheel drive system, obstacles can be added to the heating zone, transition zone, and cooling zone of the test bench as needed. For example, to measure the wheel performance and driving performance of the wheel drive system under temperature difference impact after entering the low-temperature zone from a high-temperature zone, obstacles such as stones can be set near the entrance of the cooling zone to examine the obstacle-crossing ability and structural strength of the wheel drive system under large temperature difference conditions. To measure the performance of the wheel drive system under low-temperature conditions, the wheel drive system can be kept in the cooling zone for a sufficient time, at which point the temperature of all parts of the wheel drive system will be sufficiently low. Then, obstacles such as stones can be set near the exit of the cooling zone to examine the obstacle-crossing ability and structural strength of the wheel drive system under low-temperature conditions.

[0024] In summary, the temperature shock adaptability test of the wheel drive system designed in this embodiment fully considers the driving requirements of the lunar rover and the temperature difference on the lunar surface. By simulating the actual working conditions of the wheel drive system through heating and rapid cooling, the mechanical and structural performance of the wheel drive system under long-distance and multiple alternating temperature conditions can be tested.

[0025] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. A method for verifying the cryogenic shock adaptability of a lunar wheel drive system, characterized in that, Includes the following steps: The wheel to be tested and the drive mechanism driving the wheel to be tested are installed on the test bench. The load on the wheel to be tested is adjusted and the speed of the drive mechanism is set. After the wheel under test is driven into the heating zone of the test bench, it stops and continues until the temperature of multiple parts of the wheel under test and the drive mechanism is higher than the preset temperature, then it drives out of the heating zone. After the wheel to be tested is driven into the cooling zone of the test bench, it stops and is rapidly cooled down. After the cooling time reaches the preset calibrated cooling time, it is driven out of the cooling zone. The wheel under test is driven into the heating zone to begin the second cycle. After the number of cycles reaches the preset number, the load-bearing capacity of the wheel under test is tested, and the performance of the drive mechanism is tested.

2. The method for verifying the cryogenic shock adaptability of the lunar wheel drive system according to claim 1, characterized in that, Before installing the wheel to be tested and the drive mechanism that drives the wheel to be tested on the test bench, it is necessary to conduct load-bearing capacity tests on the wheel to be tested and performance tests on the drive mechanism, so as to compare the load-bearing capacity of the wheel to be tested and the performance of the drive mechanism after the ultra-low temperature impact adaptability test.

3. The method for verifying the cryogenic shock adaptability of the lunar wheel drive system according to claim 2, characterized in that, Before and after the load-bearing capacity test, the condition of the wheel to be tested must be checked and recorded, including: the wheel surface, hub, connection of the chuck, deformation or damage.

4. The method for verifying the cryogenic shock adaptability of the lunar wheel drive system according to claim 2, characterized in that, Perform performance tests on the drive mechanism and record the drive voltage, current, and speed.

5. The method for verifying the cryogenic shock adaptability of the lunar wheel drive system according to claim 1, characterized in that, Before installing the wheel to be tested and the drive mechanism that drives the wheel to be tested on the test bench, the calibration cooling time needs to be obtained. In the cooling zone, the wheel to be tested and the drive mechanism are cooled from room temperature to the preset minimum temperature, and the time required is measured. The average value of the multiple measurements is taken as the preset calibration cooling time.

6. The method for verifying the cryogenic shock adaptability of the lunar wheel drive system according to claim 1, characterized in that, During the cyclic test, after the preset number of cycles is reached, the wheel condition is checked and recorded, including the wheel, drive, connection, mechanism operation, wheel deformation or damage.

7. The method for verifying the cryogenic shock adaptability of the lunar wheel drive system according to claim 1, characterized in that, The test bench has a ring structure and is divided into a heating zone, a transition zone, and a cooling zone. The cooling zone is equipped with a liquid helium tank, and only the part of the wheel under test below the axle is immersed in liquid helium to achieve cooling. The transition zone is covered with cotton and linen pads to absorb residual liquid helium brought out by the wheel under test from the liquid helium tank.

8. The method for verifying the cryogenic shock adaptability of the lunar wheel drive system according to claim 1, characterized in that, It also includes obstacle testing steps: setting obstacles near the entrance of the refrigeration zone to test the obstacle crossing ability and structural strength of the wheel under test under the large temperature difference condition of driving from high temperature to low temperature zone; or setting obstacles near the exit of the refrigeration zone, and after the wheel under test stays in the refrigeration zone until the temperature of each part reaches the test requirements, testing the obstacle crossing ability and structural strength under low temperature condition.

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