Manned lunar rover moving system capable of dealing with multiple faults and fault dealing method

Abstract

According to the manned lunar rover moving system capable of dealing with multiple faults and the fault dealing method, (1) when steering is damaged, wheels run normally; when steering fails but reverse driving can be achieved, the fault wheel is locked after steering and returning, and the whole vehicle adopts non-fault wheel steering; and when steering fails and reverse driving cannot be achieved, if the steering angle does not reach the limit angle when the fault wheel is locked, steering is achieved through a non-fault wheel, and if the steering angle is the limit angle when the fault wheel is locked, steering is achieved through a differential or torque coordinated distribution mode. (2) if the driving assembly is damaged and the wheel surface is not damaged, the fault wheel is driven and unlocked to be in a follow-up state; when steering is not damaged, four-wheel steering is adopted, and the steering angle of a fault wheel is adjusted to be matched with the friction braking force of each wheel and the lunar surface to achieve braking; and (3) when the wheel surface of the wheel is damaged, if steering does not fail or fails but reverse driving can be carried out, the fault wheel is steered, returned, locked and inserted into the spare wheel, and if steering fails and reverse driving cannot be carried out, the fault wheel is removed and then inserted into the spare wheel for driving.

Description

Technical Field

[0001] The present invention relates to a manned lunar rover mobile system and a fault response method capable of coping with multiple faults. The mobility of the manned lunar rover under fault conditions is ensured by isolating the driving of the driving wheel through an unlocking mechanism, locking the steering, or inserting a spare wheel to replace the driving wheel. Background Art

[0002] As an important means of transportation for future astronauts to perform missions on the moon, the manned lunar rover's mobility and return capability under fault mode are particularly important. The unknown environment on the moon has a great impact on the driving ability of the manned lunar rover's active wheels, which may cause wheel drive damage, wheel steering damage, or wheel surface damage. In order to ensure the safety of astronauts, when the manned lunar rover's mobility system fails, sufficient fault handling measures are required to ensure that it still has the ability to drive and return safely.

[0003] The manned lunar rover that has successfully landed on the moon many times is the Apollo lunar rover of the United States. All of its four wheels are active wheels. When a wheel fails to rotate, the drive can be unlocked to turn it into a passive wheel, and the remaining wheels are used to drive the vehicle to maintain driving. This method can provide a certain degree of fault response capability, but when the wheel surface fails and the wheel is completely unable to drive (such as abnormally stuck), the entire vehicle will be unable to drive, and the astronauts will still face life threats.

[0004] Patent: A detachable and reconfigurable manned lunar rover, CN202210930140.3 Beijing Space Vehicle General Design Department proposed a configuration scheme that separates a large 4-wheel vehicle into two small 3-wheel vehicles, which realizes the separation of the two vehicles when the active wheel fails and uses the undamaged small 3-wheel vehicle to return to the home position, thus ensuring the safety of the astronauts. The passive wheels of this system are folded on the bottom plate of the vehicle, and when separation is required, they are released and supported to the lunar surface. It has several obvious disadvantages: First, the driving stability of the three-wheeled vehicle is poor, and when two people are driving, the smaller passive wheel bears a larger weight, and it is easy to sink into the soft lunar soil, which rapidly increases the required driving traction. In serious cases, it may not be able to continue driving; second, it is mainly used for wheel damage at the same end, such as damage to a single front wheel or double front wheels. After separation, the rear part of the vehicle functions intact, but when one front and one rear wheel is damaged, it will not be possible to return safely. The passive wheel is in the middle of the vehicle body, so it is impossible to release the passive wheel to replace the active wheel function when the two vehicles are not separated; third, in order to separate the function, the whole vehicle adds an unlocking and separation mechanism and many components need to be made in duplicate, which has a large weight cost, high complexity, and low reliability. Comprehensive analysis shows that this patent provides a method to improve safety, but there are still defects, and there is a need for improvement.

[0005] In summary, the design of the manned lunar rover mobile system in the current research results still has room for improvement in terms of safety. Considering the launch weight and volume constraints, the main improvement direction is to use a simple mechanism to achieve fault isolation or add fewer components. Summary of the invention

[0006] The technical problem solved by the present invention is: to propose a manned lunar rover mobile system and a fault response method that can cope with multiple faults. When the driving wheel driving steering assembly fails, the driving unlocking and steering locking are realized by a joystick. At the same time, considering the extreme case that the driving wheel surface is damaged, it is proposed to insert a passive wheel to maintain the driving ability. The two methods together constitute a suspension solution for the manned lunar rover mobile system with high comprehensive safety, increased weight and small volume.

[0007] The technical solution of the present invention is: a method for coping with a manned lunar rover fault that can cope with multiple faults, the manned lunar rover has four driving wheels with independent drive and independent steering; the method for coping with the fault ensures that the whole vehicle still has the ability to return when 1 to 2 driving wheels fail. The method includes the following coping steps according to the fault form:

[0008] Fault form 1: Steering failure, the wheels run normally. When the steering fails but can be reversed, the faulty wheel is turned back to the center and then locked, and the whole vehicle uses the normal 3-wheel or 2-wheel steering. When the steering fails and cannot be reversed, if the steering angle of the faulty wheel is not at the limit angle when it is locked, the non-faulty wheel is used to achieve steering. If the steering angle is at the limit angle when it is locked, the differential or torque coordinated distribution method is used to achieve steering.

[0009] Fault form 2: When the drive fails but the wheel surface is not damaged, unlock the faulty wheel drive to follow-up state; when the steering is not damaged, use 4-wheel steering and adjust the steering angle of the faulty wheel to match the friction braking force between each wheel and the wheel surface to achieve braking. When the steering is damaged, use the coping method of fault form 1;

[0010] Fault form three: When the wheel tread is damaged, if the steering is not faulty or failed but can be reversed, the faulty wheel should be turned back and locked, and the spare wheel should be inserted to replace the driving wheel for driving; if the steering fails and cannot be reversed, the faulty wheel should be removed and the spare wheel should be inserted for driving.

[0011] Preferably, when the drive fails and the steering is not damaged, the specific processing steps are as follows:

[0012] Calculate the braking torque required for each wheel in real time. The braking torque divided by the wheel radius is the braking force. The fault wheel rotation angle = asin (braking force / (wheel lateral friction coefficient*wheel positive pressure));

[0013] When only one wheel fails, the wheels can be turned in either direction. When two wheels fail, the steering directions of the two failed wheels must be opposite to offset the lateral force.

[0014] Preferably, if only one wheel steering fails, the remaining three wheels are used to achieve steering, and the axes of the three wheels are controlled to intersect at the rotation center; if two wheels steering fail, the remaining two wheels are used to achieve steering, and the axes of the two wheels are controlled to intersect at the rotation center.

[0015] Preferably, the step of selecting a spare wheel to replace the faulty wheel with a damaged driving wheel surface according to actual conditions comprises:

[0016] If the steering is not faulty or the steering fails but can be reverse driven, the faulty wheel is straightened and the spare wheel is installed. The ground contact point of the spare wheel is lower than the ground contact point of the faulty wheel. The faulty wheel is lifted off the lunar surface and replaced by the spare wheel.

[0017] When the faulty wheel fails to turn and cannot be reversed, remove the faulty wheel and install the spare wheel to replace the faulty wheel;

[0018] In the above two cases, the contact point between the spare wheel and the ground is lower than the contact point between the other non-faulty driving wheels and the ground, and the full-wheel adhesion is achieved by moving the suspension up and down to adapt to the height difference.

[0019] A manned lunar rover mobile system realizing a manned lunar rover fault response method capable of coping with multiple faults, comprising four sets of suspension components and spare wheels, each set of suspension components comprising a suspension mounting base plate, a suspension, a drive component, a steering component, a driving wheel, and a joystick;

[0020] One end of the suspension is mounted on the bottom plate of the manned lunar rover through a suspension mounting plate, and the other end of the suspension is connected to a steering assembly, an output shaft of the steering assembly is connected to a drive assembly, the drive assembly provides driving power, and the steering assembly provides steering power;

[0021] When the wheel surface of the driving wheel is damaged, the spare wheel is installed at the corresponding interface of the steering assembly and fixed to the steering assembly housing; when the steering is not failed or failed but can be reversed, the faulty wheel is turned back to the right position and the spare wheel is directly installed without removing the faulty wheel; the spare wheel is not in contact with the driving assembly of the driving wheel and therefore has no active rotation ability, and its spare wheel rocker arm is fixed to the upper housing of the steering assembly and therefore has no steering ability. The spare wheel can only rotate passively, and its wheel forward direction is the front and rear direction of the vehicle body; after the spare wheel is installed, the faulty wheel cannot be driven or turned; when the steering fails and cannot be reversed, the driving wheel needs to be removed before the spare wheel can be installed on the upper housing of the steering assembly, and at this time the spare wheel is also in a passive rotation state.

[0022] Preferably, the driving assembly includes a driving motor assembly, a harmonic reducer, an output shaft, a fixing groove, a sliding bearing, a driving pull ring, and an elastic pressure plate;

[0023] The output shaft of the driving assembly is located at the center of the active wheel spoke plate. One end of the driving assembly is connected to the output shaft of the steering assembly through the housing flange of the driving motor assembly, and a fixing groove is installed at the other end. A sliding bearing is installed between the fixing groove and the active wheel spoke plate. The fixing groove is an annular structural member. A groove is arranged on the inner side of the structural member for realizing insertion connection with the petal structure on the output shaft of the driving assembly to realize torque transmission. The outer side of the annular structural member is provided with protrusions on both sides and an outer convex groove facing radially outward. The rectangular part of the driving pull ring passes through the active wheel spoke plate and the notch between the protrusions on both sides to the outer convex groove in sequence, and is axially limited by two spring pressure plates on the outer side. When the driving pull ring is not pulled out, it serves as a power transmission pin between the fixing groove and the active wheel spoke plate; when the driving pull ring is pulled, it breaks through the elastic force of the elastic pressure plate, and then is pulled out from the notch on the side of the fixing groove, and the driving power cannot be transmitted to the active wheel, thereby realizing that the active wheel is unlocked to a follow-up state; when the active wheel needs to be locked, the steering locking assembly realizes the fixing of the active wheel rotation angle;

[0024] The steering assembly includes a steering motor assembly, a steering harmonic reducer, and a steering output shaft; the driving motor assembly drives the output shaft to rotate through the harmonic reducer, and then transmits the torque to the active spoke plate through the fixed groove and the driving pull ring, thereby driving the wheel to rotate; the steering motor assembly drives the steering output shaft to rotate through the steering harmonic reducer, and the steering output shaft is connected to the driving motor assembly, so it will cause the driving assembly to rotate around the steering output shaft, thereby driving the wheel to steer.

[0025] Preferably, the steering lock assembly comprises a steering pull ring, a pin, a pin cylinder, a compression spring, a pin, and an intermediate housing;

[0026] The outer shell of the steering assembly is divided into an upper shell, an intermediate shell and a lower shell. The three parts are fixedly connected. The upper shell is used to install the steering motor assembly, connect the upper cross arm of the suspension and install the spare wheel; the intermediate shell is used to install the steering lock assembly, and the lower shell is used to install the steering position resolver and connect the lower cross arm of the suspension;

[0027] A pin hole is set on the intermediate shell; a pin cylinder is installed on the intermediate shell for installing a pin; a compression spring is installed between the pin and the bottom of the pin cylinder, and an inner hole is set on the side wall of the pin. In the unlocked state, the pin connected to the steering pull ring is inserted into the inner hole of the pin from the side wall of the pin cylinder, and the pre-tightening force of the compression spring is used to prevent the pin from easily falling out. When locked, the steering pull ring is pulled out and then the pin is pulled out. The pin is extended out under the thrust of the compression spring and enters the pin hole of the output shaft of the steering assembly after returning to the center position, thereby completing the locking.

[0028] Preferably, the spare wheel comprises a passive wheel rocker arm, a wheel axle assembly, a wheel, a plug, a claw, a rotating shaft, and a torsion spring;

[0029] The wheel is rotatably connected to one end of the rocker arm through the wheel axle assembly, and a plug is installed downwardly at the other end of the rocker arm. Two claws are installed inside the plug and extend outward. A torsion spring is installed between the two claws. The plug is used to cooperate with the socket on the upper shell of the wheel steering assembly. After being inserted into place, the two claws extend out and clamp into the corresponding grooves on the upper shell of the wheel steering assembly under the thrust of the torsion spring to achieve locking;

[0030] After the spare wheel is installed, the driving wheel that has not been removed will not be able to rotate or turn. The spare wheel touches the ground lower than the driving wheel. It lifts the driving wheel and replaces the driving wheel for driving, but it has no steering ability.

[0031] Preferably, the joystick comprises a hollow rod and a hook mounted on the end thereof, and the hook functions to hook the drive pull ring and the steering pull ring to achieve drive unlocking and steering locking.

[0032] Preferably, a support head is installed at the non-hook-mounted end of the joystick, which is used to prop up the vehicle body with the joystick after inserting it into the lunar soil, so as to remove the driving wheel.

[0033] The beneficial effects of the present invention compared with the prior art are:

[0034] The scheme of driving unlocking, steering locking and inserting spare wheels proposed in the present invention comprehensively ensures the safe return of the manned lunar rover mobile system under fault conditions. In extreme cases where the wheel surface is not damaged, only simple driving unlocking and steering locking are required to ensure driving capability, and the weight and volume of the added components are very small. In extreme cases where the wheel surface is damaged, the vehicle can continue to drive by inserting a spare wheel, and only two passive wheel assemblies need to be carried on the vehicle body. The passive wheel rocker arm is simple in design and operation, automatically locks when inserted, and is light in weight. The scheme proposed in this invention is simple to implement, has low weight and volume costs, and is comprehensive and effective in dealing with faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The braking configuration is that the faulty wheel follows;

[0036] Figure 2 Measures to deal with simultaneous failure of two wheels of the steering assembly;

[0037] Figure 3 To deal with steering component locking failure;

[0038] Figure 4 Suspension wheel assembly with multi-failure coping capability;

[0039] Figure 5 Cross-sectional view of the driving wheel drive fault isolation mechanism;

[0040] Figure 6 Side view of the driving wheel drive fault isolation mechanism;

[0041] Figure 7 Cross-sectional view of the driving wheel steering fault isolation mechanism;

[0042] Figure 8 joystick;

[0043] Fig. 9 Schematic diagram of spare wheel installation process;

[0044] Fig.10 Spare wheel assembly diagram;

[0045] Fig.11 Spare wheel rocker arm vertical insertion mechanism. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with the embodiments.

[0047] The manned lunar rover consists of a base plate and four sets of suspensions. Each of the four sets of suspensions has a driving wheel, and the four wheels are independently driven and independently steered. The manned lunar rover mobile system has four driving wheels 5. The failure mode mainly includes failure of 1 to 2 driving wheels 5. The failure mode response plan proposed in this invention is used to ensure that the whole vehicle still has the ability to return when 1 to 2 driving wheels 5 fail. There are three main types of driving wheel failures: damage to the wheel drive component 3, damage to the wheel steering component 4, and damage to the wheel surface of the driving wheel 5. The fault response method of the present invention ensures that the whole vehicle still has the ability to return when 1 to 2 driving wheels fail. The method mainly targets the three main fault forms of the mobile system: drive component failure, i.e., drive failure form, steering component failure, i.e., steering failure form, and wheel surface failure form. The three fault forms can occur independently or in combination. The steps of the fault response method include:

[0048] Fault form 1: Steering failure, the wheels run normally. When the steering fails but can be reversed, the faulty wheel is turned back to the center and then locked, and the whole vehicle uses the normal 3-wheel or 2-wheel steering. When the steering fails and cannot be reversed, if the steering angle of the faulty wheel is not at the limit angle when it is locked, the non-faulty wheel is used to achieve steering. If the steering angle is at the limit angle when it is locked, the differential or torque coordinated distribution method is used to achieve steering.

[0049] Fault form 2: When the drive fails but the wheel surface is not damaged, unlock the faulty wheel drive to follow-up state; when the steering is not damaged, use 4-wheel steering and adjust the steering angle of the faulty wheel to match the friction braking force between each wheel and the wheel surface to achieve braking. When the steering is damaged, use the coping method of fault form 1;

[0050] Fault form three: When the wheel tread is damaged, if the steering is not faulty or failed but can be reversed, the faulty wheel should be turned back and locked, and the spare wheel should be inserted to replace the driving wheel for driving; if the steering fails and cannot be reversed, the faulty wheel should be removed and the spare wheel should be inserted for driving.

[0051] Table 1 Troubleshooting methods

[0052]

[0053] In case of a drive failure, if the steering is not damaged, 4-wheel steering is used and the steering angle of the faulty wheel is adjusted to match the friction braking force between each wheel and the moon surface to achieve braking: When the vehicle needs to brake, the control system will calculate the braking torque required for each wheel in real time. The braking torque divided by the wheel radius is the braking force. The steering angle of the faulty wheel = asin (braking force / (wheel lateral friction coefficient*wheel positive pressure)). When only one wheel is faulty, the wheel can be turned to either side. When two wheels are faulty, the steering directions of the two faulty wheels must be opposite to offset the lateral force. Figure 1 shown.

[0054] If only one wheel fails to turn, the remaining three wheels are used to turn, and the axes of the three wheels are controlled to intersect at the rotation center; if two wheels fail to turn, the remaining two wheels are used to turn, and the axes of the two wheels are controlled to intersect at the rotation center, such as Figure 2 shown.

[0055] The present invention provides a manned lunar rover mobile system for realizing the above-mentioned fault response, such as Figure 4 As shown, it includes four sets of suspension components and a spare wheel 7. Each set of suspension components includes a suspension mounting base plate 1, a suspension 2, a drive component 3, a steering component 4, and a driving wheel 5. The whole vehicle is equipped with a joystick 6.

[0056] One end of the suspension is mounted on the bottom plate of the manned lunar rover through a suspension mounting plate 1, and the other end of the suspension is connected to a steering assembly 4, an output shaft 4-7 of the steering assembly 4 is connected to a drive assembly 3, the drive assembly 3 provides driving power, and the steering assembly 4 provides steering power;

[0057] When the wheel surface of the driving wheel is damaged, the spare wheel 7 is installed to the corresponding interface of the steering assembly 4 and fixed to the upper shell 4-8 of the steering assembly; when the steering has not failed or failed but can be reversed, the faulty wheel is returned to the normal position, and the spare wheel 7 is directly installed without removing the faulty wheel. The spare wheel 7 is not in contact with the driving assembly 3 of the driving wheel and therefore has no active rotation capability. Its spare wheel rocker arm 7-1 is fixed to the upper shell 4-8 of the steering assembly 4 and therefore has no steering capability. The spare wheel 7 can only rotate passively, and the forward direction of its wheel is the front and rear direction of the vehicle body. After the spare wheel 7 is installed, the faulty wheel cannot be driven or turned. When the steering fails and cannot be reversed, the driving wheel 5 needs to be removed before the spare wheel 7 can be installed on the upper shell 4-8 of the steering assembly. At this time, the spare wheel is also in a follow-up passive rotation state.

[0058] like Figure 5As shown, the driving assembly includes a driving motor assembly 3-7, a harmonic reducer 3-6, an output shaft 3-1, a fixing groove 3-2, a sliding bearing 3-3, a driving pull ring 3-4, and an elastic pressure plate 3-5;

[0059] The output shaft 3-1 of the driving assembly is located at the center of the active wheel spoke plate 5-1. One end of the driving assembly is connected to the output shaft 4-7 of the steering assembly through the housing flange of the driving motor assembly 3-7, and the other end is installed with a fixing groove 3-2. A sliding bearing 3-3 is installed between the fixing groove 3-2 and the active wheel spoke plate 5-1. The fixing groove 3-2 is an annular structural member. A groove is arranged on the inner side of the structural member for realizing insertion connection with the petal structure on the output shaft 3-1 of the driving assembly to realize torque transmission. The outer side of the annular structural member 3-2 is provided with protrusions on both sides and an outer convex groove facing radially outward. The driving pull ring 3-4 The rectangular part of the driving wheel spoke plate 5-1 and the notches between the protrusions on both sides sequentially pass through the driving wheel spoke plate 5-1, and the notches between the protrusions on both sides to the outer convex groove, and is axially limited by the two outer spring pressure plates 3-5. When the driving pull ring 3-4 is not pulled out, it serves as a power transmission pin between the fixed groove 3-2 and the driving wheel spoke plate 5-1; when the driving pull ring 3-4 is pulled, it breaks through the elastic force of the elastic pressure plate 3-5, and then is pulled out from the notch on the side of the fixed groove 3-2, and the driving power cannot be transmitted to the driving wheel, thereby realizing the unlocking of the driving wheel to the follow-up state; when the driving wheel needs to be locked, the steering locking assembly realizes the fixing of the driving wheel rotation angle;

[0060] like Figure 6 As shown, the driving motor assembly 3-7 drives the output shaft 3-1 to rotate through the harmonic reducer 3-6, and then transmits the torque to the active spoke plate 5-1 through the fixed groove 3-2 and the driving pull ring 3-4, thereby driving the wheel 5 to rotate; the steering motor assembly drives the steering output shaft to rotate through the steering harmonic reducer, and the steering output shaft is connected to the driving motor assembly 3-7, so it will cause the driving assembly 3 to rotate around the steering output shaft 4-7, thereby driving the wheel 5 to steer.

[0061] The steering assembly 4 includes a steering motor assembly, a steering harmonic reducer, and a steering output shaft. The steering motor assembly drives the steering output shaft to rotate through the steering harmonic reducer. The steering output shaft is connected to the driving motor assembly, so it causes the driving assembly to rotate around the steering output shaft, thereby driving the wheel to steer. The steering assembly of the present invention is similar to the internal structure of the driving assembly, but the specific models are different and the performance is different; the outer shell of the steering assembly is divided into an upper shell 4-8, an intermediate shell 4-6 and a lower shell, and the three parts are fixedly connected. The upper shell 4-8 is used to install the steering motor assembly, connect the upper cross arm of the suspension, and install the spare wheel 7; the intermediate shell 4-6 is used to install the steering lock assembly, and the lower shell is used to install the steering position resolver and connect the lower cross arm of the suspension.

[0062] like Figure 7As shown, the steering lock assembly includes a steering pull ring 4-1, a pin 4-2, a pin tube 4-3, a compression spring 4-4, a pin 4-5, and an intermediate housing 4-6; a pin hole is arranged on the intermediate housing 4-6; the pin tube 4-3 is installed on the intermediate housing 4-6 for installing the pin 4-5; a compression spring 4-4 ​​is installed between the pin 4-5 and the bottom of the pin tube 4-3, and an inner hole is arranged on the side wall of the pin 4-5. In the unlocked state, the pin 4-2 connected to the steering pull ring 4-1 is inserted into the inner hole of the pin 4-5 from the side wall of the pin tube 4-3, and the pre-tightening force of the compression spring 4-4 ​​is used to prevent the pin 4-2 from falling out easily. When locking, the steering pull ring 4-1 is pulled out and then the pin 4-2 is pulled out. The pin 4-5 is extended out under the thrust of the compression spring 4-4 ​​and enters the pin hole of the output shaft 4-7 of the steering assembly after returning to the center position to complete the locking.

[0063] like Fig. 9 , 10 As shown in Figure 11, the spare wheel includes a passive wheel rocker arm 7-1, an axle assembly 7-2, a wheel 7-3, a plug 7-4, a claw 7-5, a rotating shaft 7-6, and a torsion spring 7-7; the wheel is rotatably connected to one end of the rocker arm through the axle assembly 7-2, and a plug 7-4 is downwardly installed on the other end of the rocker arm. Two claws 7-5 are installed inside the plug 7-4 extending outward, and a torsion spring 7-7 is installed between the two claws 7-5. The plug 7-4 is used to cooperate with the socket on the upper shell 4-8 of the wheel steering assembly. After being inserted into place, the two claws 7-5 are extended and locked into the corresponding grooves on the upper shell 4-8 of the wheel steering assembly under the thrust of the torsion spring 7-7 to achieve locking.

[0064] like Figure 8 As shown, the operating lever 6 includes a hollow rod 6-2 and a hook 6-1 installed at the end thereof. The hook 6-1 is used to hook the driving pull ring 3-4 and the steering pull ring 4-1 to achieve driving unlocking and steering locking.

[0065] The non-hook-mounted end of the joystick 6 is installed with a support head 6 - 3, which is used to prop up the vehicle body with the joystick 6 after inserting it into the lunar soil, so as to remove the driving wheel 5.

[0066] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution 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 solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for coping with a manned lunar rover fault capable of coping with multiple faults, characterized in that: The manned lunar rover has four active wheels with independent driving and independent steering; The fault response method ensures that the vehicle still has the ability to return when 1-2 driving wheels fail. The response steps include: Fault form 1: Steering failure, the wheels run normally. When the steering fails but can be reversed, the faulty wheel is turned back to the center and then locked, and the whole vehicle uses the normal 3-wheel or 2-wheel steering. When the steering fails and cannot be reversed, if the steering angle of the faulty wheel is not at the limit angle when it is locked, the non-faulty wheel is used to achieve steering. If the steering angle is at the limit angle when it is locked, the differential or torque coordinated distribution method is used to achieve steering. Fault form 2: When the drive fails but the wheel surface is not damaged, unlock the faulty wheel drive to follow-up state; when the steering is not damaged, use 4-wheel steering and adjust the steering angle of the faulty wheel to match the friction braking force between each wheel and the wheel surface to achieve braking. When the steering is damaged, use the coping method of fault form 1; Fault form three: When the wheel tread is damaged, if the steering is not faulty or failed but can be reversed, the faulty wheel should be turned back and locked, and the spare wheel should be inserted to replace the driving wheel for driving; if the steering fails and cannot be reversed, the faulty wheel should be removed and the spare wheel should be inserted for driving.

2. The method according to claim 1, characterized in that: When the drive fails and the steering is not damaged, the specific processing steps are as follows: Calculate the braking torque required for each wheel in real time. The braking torque divided by the wheel radius is the braking force. The fault wheel rotation angle = asin (braking force / (wheel lateral friction coefficient*wheel positive pressure)); When only one wheel fails, the wheels can be turned in either direction. When two wheels fail, the steering directions of the two failed wheels must be opposite to offset the lateral force.

3. The method according to claim 1, characterized in that: If only one wheel fails to turn, the remaining three wheels are used to steer, and the axes of the three wheels are controlled to intersect at the center of rotation; if two wheels fail to turn, the remaining two wheels are used to steer, and the axes of the two wheels are controlled to intersect at the center of rotation.

4. The method according to claim 1, characterized in that: The method of selecting a spare wheel to replace the faulty wheel of the driving wheel with a damaged wheel surface according to the actual situation comprises: If the steering is not faulty or the steering fails but can be reverse driven, the faulty wheel is straightened and the spare wheel is installed. The ground contact point of the spare wheel is lower than the ground contact point of the faulty wheel. The faulty wheel is lifted off the lunar surface and replaced by the spare wheel. When the faulty wheel fails to turn and cannot be reversed, remove the faulty wheel and install the spare wheel to replace the faulty wheel; In the above two cases, the contact point between the spare wheel and the ground is lower than the contact point between the other non-faulty driving wheels and the ground, and the full-wheel adhesion is achieved by moving the suspension up and down to adapt to the height difference.

5. A manned lunar rover mobile system that implements the manned lunar rover fault response method capable of coping with multiple faults as claimed in claim 1, characterized in that: It includes four sets of suspension components and spare wheels. Each set of suspension components includes a suspension mounting base plate, a suspension, a driving component, a steering component, a driving wheel and a joystick. One end of the suspension is mounted on the bottom plate of the manned lunar rover through a suspension mounting plate, and the other end of the suspension is connected to a steering assembly, an output shaft of the steering assembly is connected to a drive assembly, the drive assembly provides driving power, and the steering assembly provides steering power; The spare wheel is installed at the corresponding interface of the steering assembly and fixed to the steering assembly housing when the driving wheel surface is damaged; when the steering is not failed or failed but can be reversed, the faulty wheel is returned to the normal position and the spare wheel is directly installed without disassembling the faulty wheel; When the steering fails and cannot be reverse driven, the driving wheel needs to be removed and the spare wheel installed on the steering assembly housing; the spare wheel has no active rotation and steering capabilities and is in a follow-up passive rotation state.

6. The manned lunar rover mobile system according to claim 5, characterized in that: The driving assembly includes a driving motor assembly, a harmonic reducer, an output shaft, a fixing groove, a sliding bearing, a driving pull ring, and an elastic pressure plate; The output shaft of the driving assembly is located at the center of the active wheel spoke plate. One end of the driving assembly is connected to the output shaft of the steering assembly through the housing flange of the driving motor assembly, and a fixing groove is installed at the other end. A sliding bearing is installed between the fixing groove and the active wheel spoke plate. The fixing groove is an annular structural member. A groove is arranged on the inner side of the structural member for realizing insertion connection with the petal structure on the output shaft of the driving assembly to realize torque transmission. The outer side of the annular structural member is provided with protrusions on both sides and an outer convex groove facing radially outward. The rectangular part of the driving pull ring passes through the active wheel spoke plate and the notch between the protrusions on both sides to the outer convex groove in sequence, and is axially limited by two spring pressure plates on the outer side. When the driving pull ring is not pulled out, it serves as a power transmission pin between the fixing groove and the active wheel spoke plate; when the driving pull ring is pulled, it breaks through the elastic force of the elastic pressure plate, and then is pulled out from the notch on the side of the fixing groove, and the driving power cannot be transmitted to the active wheel, thereby realizing that the active wheel is unlocked to a follow-up state; when the active wheel needs to be locked, the steering locking assembly realizes the fixing of the active wheel rotation angle; The steering assembly includes a steering motor assembly, a steering harmonic reducer, and a steering output shaft; The driving motor assembly drives the output shaft to rotate through the harmonic reducer, and then transmits the torque to the active wheel spoke plate through the fixed groove and the driving pull ring, thereby driving the wheel to rotate; The steering motor assembly drives the steering output shaft to rotate through the steering harmonic reducer. The steering output shaft is connected to the drive motor assembly, so it causes the drive assembly to rotate around the steering output shaft, thereby driving the wheels to steer.

7. The manned lunar rover mobile system according to claim 6, characterized in that: The steering lock assembly comprises a steering pull ring, a pin, a pin cylinder, a compression spring, a pin, and an intermediate housing; The outer shell of the steering assembly is divided into an upper shell, an intermediate shell and a lower shell. The three parts are fixedly connected. The upper shell is used to install the steering motor assembly, connect the upper cross arm of the suspension and install the spare wheel; the intermediate shell is used to install the steering lock assembly, and the lower shell is used to install the steering position resolver and connect the lower cross arm of the suspension; A pin hole is set on the intermediate shell; a pin cylinder is installed on the intermediate shell for installing a pin; a compression spring is installed between the pin and the bottom of the pin cylinder, and an inner hole is set on the side wall of the pin. In the unlocked state, the pin connected to the steering pull ring is inserted into the inner hole of the pin from the side wall of the pin cylinder, and the pre-tightening force of the compression spring is used to prevent the pin from easily falling out. When locked, the steering pull ring is pulled out and then the pin is pulled out. The pin is extended out under the thrust of the compression spring and enters the pin hole of the output shaft of the steering assembly after returning to the center position, thereby completing the locking.

8. The manned lunar rover mobile system according to claim 7, characterized in that: The spare wheel comprises a passive wheel rocker arm, a wheel axle assembly, a wheel, a plug, a claw, a rotating shaft, and a torsion spring; The wheel is rotatably connected to one end of the rocker arm through an axle assembly, and a plug is installed downwardly at the other end of the rocker arm. Two claws are installed inside the plug to extend outward, and a torsion spring is installed between the two claws. The plug is used to cooperate with the socket on the upper shell of the wheel steering assembly. After being inserted into place, the two claws extend out under the thrust of the torsion spring and are clamped into the corresponding grooves on the upper shell of the wheel steering assembly to achieve locking.

9. The manned lunar rover mobile system according to claim 5, characterized in that: The joystick comprises a hollow rod and a hook mounted on the end thereof. The hook is used to hook the driving pull ring and the steering pull ring to achieve driving unlocking and steering locking.

10. The manned lunar rover mobile system according to claim 9, characterized in that: The non-hook-mounted end of the joystick is installed with a support head, which is used to prop up the vehicle body with the joystick after inserting it into the lunar soil, so as to remove the driving wheel.

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