Manned lunar rover based on rotating speed coupling driving of differential mechanism

Abstract

The invention belongs to the technical field of planetary exploration vehicle engineering, and particularly relates to a manned lunar rover based on differential rotation speed coupling drive. Comprising a frame, a power coupling system, a damping spring assembly, a cross shaft universal joint assembly, a cantilever assembly and wheel assemblies, the power coupling system is arranged on the frame, the output ends of the two sides of the power coupling system are connected with the two wheel assemblies respectively, and the wheel assemblies are hinged to the frame through the cantilever assembly. The two sides of the frame are each provided with two damping spring assemblies, and the damping spring assemblies are connected with the wheel assemblies. The power coupling system can realize switching between a single-motor power output mode and a dual-motor coupling power output mode. The differential rotating speed coupling design is introduced, so that it is guaranteed that the lunar rover can still run safely even if part of motors fail, and meanwhile the energy efficiency and the passing performance under the complex terrain are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of planetary exploration vehicle engineering, and in particular relates to a manned lunar rover based on differential speed coupling drive. Background Art

[0002] With the advancement of manned lunar exploration missions, the reliability of the lunar rover's drive system has become a core technical indicator related to the safety of astronauts. Existing four-wheel independent drive systems mostly adopt a multi-motor distributed layout. Although it can achieve flexible steering control, there is a risk of single-point failure: when a drive motor stops due to extreme temperature differences on the lunar surface, lunar dust intrusion or mechanical failure, it will cause the drive torque of the entire wheel system to be unbalanced, and in severe cases, it may cause the vehicle to lose its ability to move. Traditional solutions mostly use full-time multi-motor redundant configurations, such as equipping each wheel with a dual-motor drive device. However, this solution significantly increases the mass of the system, and the continuous operation of all motors will double the energy consumption, which is fundamentally inconsistent with the energy supply mode that relies on limited solar power during the lunar night. In addition, existing differential devices are mostly used for torque distribution of ground vehicles, and there has been no case of creatively applying the differential speed coupling characteristics to motor failure redundancy.

[0003] The current lunar rover drive system faces three major technical bottlenecks: (1) The contradiction between the redundancy mechanism and lightweight design is prominent, and excessive redundant configuration leads to excessive quality; (2) The existing fault-tolerant solution needs to cut off the power of the entire wheel when the motor fails, sacrificing the available driving force of the remaining motors; (3) The complex lunar terrain (such as slopes above 20° and soft lunar soil areas) has sharply increased the demand for instantaneous driving force, but continuous full-power operation has exacerbated the energy crisis. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a manned lunar rover based on differential speed coupling drive to solve the problem that the motor failure in the existing four-wheel drive motor system may cause the whole vehicle to be unable to drive, especially for applications in extreme environments such as the lunar surface. The existing four-wheel motor drive system usually has the risk of motor failure. Once the motor fails, it may cause the corresponding wheel to lose power, causing the lunar rover to get into trouble or even be unable to continue driving. Therefore, the present invention introduces a differential speed coupling design to ensure that the lunar rover can still drive safely even when some motors fail, while improving energy efficiency and passing performance in complex terrain.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a manned lunar rover based on differential speed coupling drive, comprising a frame, a power coupling system, a shock absorbing spring assembly, a cross-axis universal joint assembly, a cantilever assembly and a wheel assembly, wherein the power coupling system is arranged on the frame, and the output ends on both sides of the power coupling system are respectively connected to two wheel assemblies, the wheel assembly is hinged to the frame through the cantilever assembly, and two groups of shock absorbing spring assemblies are arranged on both sides of the frame, and the shock absorbing spring assembly is connected to the wheel assembly; the power coupling system can realize the switching between a single-motor power output mode and a dual-motor coupling power output mode.

[0006] The power coupling system comprises a coupling device mounting frame, a housing, and a drive motor I, an electromagnetic brake I, a differential speed coupling device, an electromagnetic brake II, a drive motor II and a secondary reduction device installed in the housing, wherein a drive motor output shaft I of the drive motor I is connected to an input shaft of the differential speed coupling device, a drive motor output shaft II of the drive motor II is connected to another input shaft of the differential speed coupling device, and the front ends of the drive motors I and II are respectively provided with electromagnetic brakes I and electromagnetic brakes II for braking the output shafts; the output shaft of the differential speed coupling device is connected to the input shaft of the secondary reduction device; The shell is mounted on a coupling device mounting frame, and the coupling device mounting frame is connected to the vehicle frame.

[0007] The differential speed coupling device comprises a coupling device housing, an input bevel gear shaft, a driven bevel gear, a planetary gear assembly I and two half-shaft bevel gears I, wherein the input bevel gear shaft is connected to the output shaft I of the drive motor, the coupling device housing is rotationally connected to the housing, the driven bevel gear is fixedly arranged on the outside of the coupling device housing, and the driven bevel gear is meshed with the input bevel gear shaft, and the drive motor I provides power for the rotation of the coupling device housing; The planetary gear assembly I is arranged in the coupling device housing, and the two half-shaft bevel gears I are rotatably installed in the coupling device housing, and the rotation axes are collinear; the two half-shaft bevel gears I are respectively located on both sides of the planetary gear assembly I and are both meshed with the planetary gear assembly I; the two half-shaft bevel gears I are respectively connected to the output shaft II of the drive motor and the input shaft of the secondary reduction device.

[0008] The planetary gear assembly I includes a planetary gear shaft I and two planetary gears I, wherein the planetary gear shaft I is fixed in the coupling device housing, and the axis of the planetary gear shaft I is perpendicular to the axis of the half-shaft bevel gear I; the two planetary gears I are rotatably mounted on both ends of the planetary gear shaft I through needle bearings, and the backs of the two planetary gears I are connected to the coupling device housing through thrust ball bearings I; the two planetary gears I are meshed with the half-shaft bevel gears I on both sides.

[0009] The secondary reduction device comprises a secondary reduction device output shaft I, a secondary reduction device output shaft II, an input gear shaft, an intermediate gear shaft, a driven helical gear, a differential housing and a differential planetary gear mechanism, wherein the input gear shaft, the intermediate gear shaft and the driven helical gear are rotatably mounted on the housing and meshed in sequence, and the input gear shaft is connected to the output shaft of the differential speed coupling device; the driven helical gear is fixedly mounted on the differential housing, and the differential housing is rotatably connected to the housing, and the secondary reduction device output shaft I and the secondary reduction device output shaft II are rotatably mounted on both sides of the differential housing, and the axes are collinear; The differential planetary gear mechanism is arranged in the differential housing, and the differential planetary gear mechanism is connected to the secondary reduction device output shaft I and the secondary reduction device output shaft II, and the differential planetary gear mechanism is used to distribute power to the secondary reduction device output shaft I and the secondary reduction device output shaft II.

[0010] The differential planetary gear mechanism comprises a planetary gear assembly II and two half-shaft bevel gears II, wherein the planetary gear assembly II is arranged in the differential housing, and the two half-shaft bevel gears II are rotatably mounted on both sides of the differential housing, and the rotation axes are collinear; the two half-shaft bevel gears II are both meshed with the planetary gear assembly II, and the two half-shaft bevel gears II are coaxially connected to the output shaft I of the secondary reduction device and the output shaft II of the secondary reduction device respectively; The planetary gear assembly II includes a planetary gear shaft II and two planetary gears II rotatably mounted at both ends of the planetary gear shaft II. Planetary gear gaskets are provided on the backs of the two planetary gears II. Each planetary gear II is meshed with the half-shaft bevel gears II on both sides.

[0011] The electromagnetic brake I and the electromagnetic brake II have the same structure, and both include a brake housing and an elastic guide assembly, an electromagnet, an armature and a brake disc installed in the brake housing, wherein the brake housing is rotatably installed on the output shaft I of the drive motor or the output shaft II of the drive motor, and the brake housing is fixedly connected to the housing; the brake disc is connected to the output shaft I of the drive motor or the output shaft II of the drive motor through a spline shaft; The electromagnet is embedded in the inner side of the brake housing, the armature is arranged between the electromagnet and the brake disc, and the armature is connected to the brake housing through an elastic guide component; when the electromagnet is energized, the armature is adsorbed to the electromagnet; when the electromagnet is de-energized, the elastic guide component pushes the armature to fit the brake disc to achieve braking.

[0012] The wheel assembly includes a wheel, a wheel connecting shaft and a wheel fixing frame, wherein one end of the wheel connecting shaft is connected to the wheel, and the other end is connected to the output end of the power coupling system through a cross-axis universal joint assembly, and the wheel fixing frame is installed on the wheel connecting shaft through a thrust ball bearing III.

[0013] The cantilever assembly includes a connecting shaft I, a connecting shaft II, a lower fork arm, an upper fork arm and a connecting shaft VI, wherein the upper fork arm and the lower fork arm are arranged in parallel at the upper and lower sides of the wheel fixing frame, and one end of the upper fork arm and the lower fork arm is hinged to the frame through the connecting shaft I, and the other end of the upper fork arm and the lower fork arm is respectively hinged to the upper and lower sides of the wheel fixing frame through the connecting shaft VI; connecting shafts II are provided on both sides of the other end of the lower fork arm close to the frame, and connecting shafts II are used to be hinged to the lower end of the shock-absorbing spring assembly; the upper end of the shock-absorbing spring assembly is hinged to the coupling device mounting frame through the connecting shaft III.

[0014] The manned lunar rover based on differential speed coupling drive also includes front wheels, a front wheel shock absorbing system, a front support frame and a rear support frame, wherein the front support frame and the rear support frame are respectively arranged at the front and rear ends of the frame, and front wheels are arranged on both sides of the front end of the frame, and the front wheels are hinged to the frame through the front wheel shock absorbing system.

[0015] The advantages and beneficial effects of the present invention are as follows: the present invention provides a manned lunar rover based on differential speed coupling drive, which solves the problem that the existing four-wheel motor drive system cannot provide redundant power when the motor fails by adopting the differential speed coupling design, thereby ensuring the continuous driving ability of the manned lunar rover; through the cooperation of the electromagnetic brake, measures can be taken quickly when the motor fails to prevent the faulty motor from having adverse effects on the entire vehicle. In addition, the system not only improves the stability and efficiency of power transmission through the combination of speed coupling and a secondary reduction device, but also realizes stepless speed control, so that the lunar rover can flexibly respond to various driving needs in complex terrain.

[0016] The present invention significantly improves the driving safety, stability, reliability and energy utilization of the manned lunar rover, and is an innovative lunar rover with broad application prospects in extreme environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of a manned lunar rover based on differential speed coupling drive of the present invention; Figure 2 It is a structural schematic diagram of the differential speed coupling drive system in the present invention; Figure 3 It is a structural schematic diagram of the differential speed coupling device in the present invention; Figure 4 It is a schematic diagram of an explosion of the electromagnetic brake in the present invention; Figure 5 is a cross-sectional view of the electromagnetic brake of the present invention; Figure 6 It is a schematic structural diagram of the two-stage reduction device in the present invention.

[0018] In the figure: 1-drive motor Ⅰ, 11-motor housing Ⅰ, 12-bolt Ⅰ, 2-electromagnetic brake Ⅰ, 21-drive motor output shaft Ⅰ, 22-coupling, 23-tapered roller bearing Ⅰ, 3-differential speed coupling device, 31-deep groove ball bearing Ⅰ, 32-coupling device housing, 331-tapered roller bearing Ⅱ, 332-input bevel gear shaft, 341-driven bevel gear, 342-bolt Ⅱ, 35-planetary gear assembly Ⅰ, 351-planetary gear Ⅰ, 352-thrust ball bearing Ⅰ, 353-planetary gear shaft Ⅰ, 354-needle roller bearing, 361-semi-axle gear tapered roller bearing, 362-semi-axle bevel gear Ⅰ, 371-bearing fixing Sleeve, 372-bolt III, 4-housing, 41-hexagon head screw I, 42-hexagon head screw II, 43-housing end cover, 5-deep groove ball bearing II, 51-bearing pressure cover, 6-electromagnetic brake II, 61-drive motor output shaft II, 62-brake housing, 63-armature guide shaft, 64-electromagnet, 65-spring, 66-armature, 67-brake disc, 671-friction plate, 672-brake disc body, 673-rivet, 68-adjusting gasket, 69-thrust ball bearing II, 7-drive motor II, 71-bolt VI, 72-motor housing II, 8-coupling device mounting frame, 81-deep groove ball bearing III, 82-housing connector I, 83-housing Body connector Ⅱ, 9-secondary reduction device, 91-secondary reduction device output shaft Ⅰ, 92-secondary reduction device output shaft Ⅱ, 931-bearing end cover Ⅰ, 932-bolt Ⅴ, 941-tapered roller bearing Ⅲ, 942-input gear shaft, 943-deep groove ball bearing Ⅵ, 944-intermediate gear shaft, 951-bolt Ⅳ, 952-bearing end cover Ⅱ, 953-tapered roller bearing Ⅵ, 961-friction reduction gasket, 962-semi-axle bevel gear Ⅱ, 971-driven helical gear, 972-bolt Ⅶ, 98-planetary gear assembly Ⅱ, 981-planetary gear shaft Ⅱ, 982-planetary gear Ⅱ, 983-planetary gear gasket, 99-differential housing, 1 01-front wheel, 102-front wheel shock absorption system, 103-front support frame, 104-frame, 105-rear support frame, 106-power coupling system, 107-shock absorption spring assembly, 108-cross shaft universal joint assembly, 109-cantilever assembly, 1091-connecting shaft I, 1092-shaft retaining ring, 1093-connecting shaft II, 1094-connecting shaft III, 1095-lower fork arm, 1096-upper fork arm, 1097-connecting shaft VI, 20-wheel assembly, 201-fixing nut, 202-wheel, 203-wheel connecting shaft, 204-thrust ball bearing III, 205-wheel fixing frame, 206-end cover, 208-tightening nut. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] See also Figure 1 As shown, the present invention provides a manned lunar rover based on differential speed coupling drive, including a frame 104, a power coupling system 106, a shock absorbing spring assembly 107, a cross-axis universal joint assembly 108, a cantilever assembly 109 and a wheel assembly 20, wherein the power coupling system 106 is arranged on the frame 104, and the output ends on both sides of the power coupling system 106 are respectively connected to the two wheel assemblies 20, and the wheel assembly 20 is hinged to the frame 104 through the cantilever assembly 109, and two groups of shock absorbing spring assemblies 107 are arranged on both sides of the frame 104, and the shock absorbing spring assembly 107 is connected to the wheel assembly 20; the power coupling system 106 can realize the switching between the single-motor power output mode and the dual-motor coupling power output mode.

[0021] See also Figure 1 As shown, in an embodiment of the present invention, a manned lunar rover based on differential speed coupling drive provided by the present invention also includes front wheels 101, a front wheel shock absorbing system 102, a front support frame 103 and a rear support frame 105, wherein the front support frame 103 and the rear support frame 105 are respectively arranged at the front and rear ends of a frame 104, and front wheels 101 are arranged on both sides of the front end of the frame 104, and the front wheels 101 are hinged to the frame 104 through the front wheel shock absorbing system 102.

[0022] See also Figure 2 As shown, in the embodiment of the present invention, the power coupling system 106 includes a coupling device mounting frame 8, a housing 4, and a drive motor Ⅰ1, an electromagnetic brake Ⅰ2, a differential speed coupling device 3, an electromagnetic brake Ⅱ6, a drive motor Ⅱ7 and a secondary reduction device 9 installed in the housing 4, wherein the drive motor output shaft Ⅰ21 of the drive motor Ⅰ1 is connected to an input shaft of the differential speed coupling device 3, and the drive motor output shaft Ⅱ61 of the drive motor Ⅱ7 is connected to another input shaft of the differential speed coupling device 3. The front ends of the drive motor Ⅰ1 and the drive motor Ⅱ7 are respectively provided with electromagnetic brakes Ⅰ2 and electromagnetic brakes Ⅱ6 for braking the output shafts; the output shaft of the differential speed coupling device 3 is connected to the input shaft of the secondary reduction device 9, the housing 4 is installed on the coupling device mounting frame 8, the coupling device mounting frame 8 is connected to the frame 104, and the differential speed coupling device 3 can realize single-motor power output or dual-motor coupled power output to the secondary reduction device 9.

[0023] See also Figure 3As shown, in the embodiment of the present invention, the differential speed coupling device 3 includes a coupling device housing 32, an input bevel gear shaft 332, a driven bevel gear 341, a planetary gear assembly I35 and two half-shaft bevel gears I362, wherein the input bevel gear shaft 332 is connected to the output shaft I21 of the driving motor through the coupling 22, and the coupling 22 and the input bevel gear shaft 332 are rotatably connected to the housing 4 through the tapered roller bearing I23 and the tapered roller bearing II331 respectively; deep groove ball bearings I31 are provided at both ends of the coupling device housing 32, and a bearing fixing sleeve 371 is provided on the outer side of the deep groove ball bearing I31, and the bearing fixing sleeve 371 is fixedly connected to the housing 4 through bolts III372, and the coupling device housing 32 can rotate relative to the housing 4. The driven bevel gear 341 is fixed to the outer end of the coupling device housing 32 by bolts II 342, and the driven bevel gear 341 is meshed with the input bevel gear shaft 332, and the driving motor I1 provides power for the rotation of the coupling device housing 32; the planetary gear assembly I35 is arranged in the coupling device housing 32, and the two half-shaft bevel gears I362 are rotatably installed in the coupling device housing 32 through the half-shaft gear tapered roller bearings 361, and the rotation axes are collinear; the two half-shaft bevel gears I362 are respectively located on both sides of the planetary gear assembly I35 and are both meshed with the planetary gear assembly I35; the two half-shaft bevel gears I362 are respectively connected to the output shaft II61 of the driving motor and the input shaft of the secondary reduction device 9.

[0024] See also Figure 3 As shown, in the embodiment of the present invention, the planetary gear assembly Ⅰ35 includes a planetary gear shaft Ⅰ353 and two planetary gears Ⅰ351, wherein the planetary gear shaft Ⅰ353 is fixed in the coupling device housing 32, and the axis of the planetary gear shaft Ⅰ353 is perpendicular to the axis of the half-shaft bevel gear Ⅰ362; the two planetary gears Ⅰ351 are rotatably mounted on both ends of the planetary gear shaft Ⅰ353 through needle bearings 354, and the backs of the two planetary gears Ⅰ351 are connected to the coupling device housing 32 through thrust ball bearings Ⅰ352; the two planetary gears Ⅰ351 are meshed with the half-shaft bevel gears Ⅰ362 on both sides.

[0025] Specifically, the thrust ball bearing I352 of the planetary gear I351 is used to bear the axial force, and convert the sliding friction between the planetary gear I351 and the coupling device housing 32 into rolling friction; the needle bearing 354 is used to bear the radial force, and convert the sliding friction between the planetary gear I351 and the planetary gear shaft I353 into rolling friction. The half-shaft bevel gear I362 rotates with the spline shaft under the drive of the spline shaft, and will rub against the housing under the action of the axial force. Therefore, the half-shaft gear tapered roller bearing 361 is installed at the contact point between the half-shaft bevel gear I362 and the coupling device housing 32, which can not only support the spline shaft but also convert the sliding friction into rolling friction.

[0026] The planetary gear shaft of the traditional differential is a smooth shaft, and sliding friction will occur when the planetary gear rotates relative to the shaft. In order to avoid severe friction under the influence of the speed difference, the present invention installs a K-type needle roller bearing 354 on the planetary gear shaft I 353. The needle roller bearing 354 has a small radial size and a simple structure, and can be directly installed on the planetary gear shaft I 353.

[0027] Specifically, the coupling housing 32 is made of high-strength cast iron, and the overall structure is a complex geometric shape. Precision mounting seats and bearing cavities are set inside to accommodate the internal gears and bearings, which is convenient for assembly and maintenance. Reinforcement ribs are designed at key locations, and the surface is treated with corrosion-resistant coating to increase service life. Heat dissipation requirements are taken into account during the design process to ensure that the differential works normally under high load and high temperature conditions.

[0028] In an embodiment of the present invention, the differential speed coupling device 3 is used to smoothly couple the driving speeds of the drive motor I1 and the drive motor II7, so that the output speeds of the drive motor I1 and the drive motor II7 are linearly superimposed as needed. Considering the compactness and stability of the structure, the input bevel gear shaft 332 adopts a cantilever double-bearing fixed support. The differential speed coupling device 3 can not only accurately synchronize the speeds of the two drive motors, but also has an efficient energy transfer function, reduces energy loss, and improves the efficiency of the overall system. Due to the speed coupling characteristics of the differential, the lunar rover can intelligently switch the working mode according to actual needs under different driving conditions to achieve efficient power output.

[0029] See also Figure 6 As shown, in the embodiment of the present invention, the two-stage reduction device 9 includes a two-stage reduction device output shaft I 91, a two-stage reduction device output shaft II 92, an input gear shaft 942, an intermediate gear shaft 944, a driven bevel gear 971, a differential housing 99 and a differential planetary gear mechanism, wherein the input gear shaft 942, the intermediate gear shaft 944 and the driven bevel gear 971 are rotatably mounted on the housing 4 and meshed in sequence, the input gear shaft 942 is connected to the half-shaft bevel gear I 362 of the differential speed coupling device 3, and the intermediate gear shaft 944 is used to connect and transmit power to the half-shaft gears. The driven bevel gear 971 is fixedly mounted on the outer end of the differential housing 99 by bolts VII 972. The differential housing 99 is rotationally connected to the housing 4. The secondary reduction device output shaft I91 and the secondary reduction device output shaft II 92 are rotationally mounted on both sides of the differential housing 99 by tapered roller bearings VI 953, and the axes are collinear. The differential planetary gear mechanism is arranged in the differential housing 99. The differential planetary gear mechanism is connected to the secondary reduction device output shaft I91 and the secondary reduction device output shaft II 92. The differential planetary gear mechanism is used to distribute power to the secondary reduction device output shaft I91 and the secondary reduction device output shaft II 92.

[0030] See also Figure 6 As shown, in the embodiment of the present invention, the differential planetary gear mechanism includes a planetary gear assembly II98 and two half-shaft bevel gears II962, wherein the planetary gear assembly II98 is arranged in the differential housing 99, and the two half-shaft bevel gears II962 are rotatably mounted on both sides of the differential housing 99, and the rotation axes are collinear; the two half-shaft bevel gears II962 are both meshed with the planetary gear assembly II98, and the two half-shaft bevel gears II962 are coaxially connected to the secondary reduction device output shaft I91 and the secondary reduction device output shaft II92, respectively. Further, the backs of the two half-shaft bevel gears II962 are provided with anti-friction washers 961, and the anti-friction washers 961 are used to reduce the friction between the half-shaft bevel gears II962 and the differential housing 99, and the ends of the secondary reduction device output shaft I91 and the secondary reduction device output shaft II92 are both internal splines.

[0031] In an embodiment of the present invention, the planetary gear assembly II98 includes a planetary gear shaft II981 and two planetary gears II982 rotatably mounted at both ends of the planetary gear shaft II981, and planetary gear gaskets 983 are provided on the backs of the two planetary gears II982; each planetary gear II982 is meshed with the half-shaft bevel gears II962 on both sides.

[0032] Furthermore, the two ends of the secondary reduction device 9 are respectively provided with a bearing end cover I931 and a bearing end cover II952, the bearing end cover I931 is connected to the housing 4 through a bolt V932, and the bearing end cover II952 is connected to the housing 4 through a bolt IV951. The input gear shaft 942 is connected to the bearing end cover I931 through a tapered roller bearing III941, and the two ends of the intermediate gear shaft 944 are respectively connected to the bearing end cover I931 and the bearing end cover II952 through a deep groove ball bearing VI943.

[0033] Furthermore, the housing 4 is arranged on two coupling device mounting frames 8, the two coupling device mounting frames 8 are connected to the vehicle frame 4, and the secondary reduction device output shaft I 91 and the secondary reduction device output shaft II 92 are rotatably connected to the two coupling device mounting frames 8 through deep groove ball bearings III 81. A housing end cover 43 is provided on the side of the housing 4 opposite to the drive motor I, and the housing end cover 43 is connected to the housing 4 through a hexagon head screw II 42, and a housing connector 82 is provided on the side wall of the housing 4.

[0034] In the embodiment of the present invention, the secondary reduction device 9 adopts a helical gear reduction mechanism to ensure smooth power transmission and efficient power conversion, play the role of reducing speed and increasing torque, and reasonably distribute the torque from the drive motor I1 and the drive motor II7 to the left and right wheels; the differential planetary gear mechanism evenly distributes power through the coordinated work of the planetary gear II 982 and the half-shaft bevel gear II 962, ensuring that the vehicle maintains stable driving under turning or different load conditions.

[0035] See also Figure 4 and Figure 5 As shown, in the embodiment of the present invention, the electromagnetic brake I2 and the electromagnetic brake II6 have the same structure, both of which include a brake housing 62 and an elastic guide assembly, an electromagnet 64, an armature 66 and a brake disc 67 installed in the brake housing 62, wherein the brake housing 62 is rotatably installed on the drive motor output shaft I21 or the drive motor output shaft II61 through a deep groove ball bearing II5, and one end of the brake housing 62 is fixedly connected to the housing of the drive motor I1 or the drive motor II7 by a bolt VI71, and an adjustment gasket 68 is provided between the brake housing 62 and the housing of the drive motor I1 or the drive motor II7, and the adjustment gasket 68 is used to adjust the gap between the drive motor II7 and the brake housing 62, and is fixed by a bolt VI71. The other end of the brake housing 62 is connected to the housing 4 by a hexagon head screw I41. The brake disc 67 is fixed on the drive motor output shaft Ⅰ21 or the drive motor output shaft Ⅱ61 through a spline shaft; the electromagnet 64 is embedded in the inner side of the brake housing 62, the armature 66 is arranged between the electromagnet 64 and the brake disc 67, and the armature 66 is connected to the brake housing 62 through an elastic guide component; when the electromagnet 64 is energized, the armature 66 is adsorbed on the electromagnet 64; when the electromagnet 64 is de-energized, the elastic guide component pushes the armature 66 to fit the brake disc 67 to achieve braking.

[0036] Specifically, the elastic guide assembly includes a plurality of armature guide shafts 63 and a plurality of springs 65 which are circumferentially arranged on the inner side of the brake housing 62, wherein the plurality of armature guide shafts 63 are located on the inner side of the electromagnet 64, the armature 66 slides with the plurality of armature guide shafts 63 through guide holes, and the plurality of springs 65 are located on the outer side of the electromagnet 64 and abut against the armature 66, and the springs 65 can push the armature 66 to move axially.

[0037] In an embodiment of the present invention, the brake disc 67 includes a friction plate 671 and a brake disc body 672, wherein the brake disc body 672 is key-connected to the drive motor output shaft Ⅰ21 or the drive motor output shaft Ⅱ61, and the back of the brake disc body 672 is rotatably connected to the housing of the drive motor Ⅰ1 or the drive motor Ⅱ7 through a thrust ball bearing Ⅱ69, and the friction plate 671 is fixed to the front end face of the brake disc body 672 by a rivet 673.

[0038] Specifically, the electromagnetic brake is used to quickly apply braking force when a motor fails, so that the faulty motor stops rotating, thereby ensuring that the other motor can continue to provide power. The brake housing 62 is used to protect the internal components and provide structural support, and has sealing properties to prevent dust and impurities from entering the interior. The electromagnet 64 is one of the key components. Its internal coil is wound with insulated copper wire. When the coil is energized, a magnetic field is generated to attract the armature 66 to release the brake. The movable part of the armature 66 is made of soft magnetic material, and the contact with the brake disc 67 is a high friction flange located near the electromagnetic coil. When power is turned on, the magnetic force generated by the electromagnetic coil attracts the armature 66, and the armature 66 overcomes the spring force and moves, thereby releasing the brake. The function of the spring 65 is to provide a reaction force when the power is off, push the armature 66 back to the initial position, compress the brake disc 67, and generate braking force. The brake disc 67 is fixed to the motor output shaft through a spline, and the friction plate 671 needs to have a high friction coefficient and wear resistance, and is made of synthetic materials to generate friction to achieve braking.

[0039] Working principle of electromagnetic brake Ⅰ2 and electromagnetic brake Ⅱ6: When the coil of the electromagnet 64 is energized, the electromagnet 64 generates an electromagnetic force to attract the armature 66, and the armature 66 approaches the brake housing 62 through the armature guide shaft 63. When the coil of the electromagnet 64 loses power, the armature 66 is pushed toward the brake disc 67 by the spring 65 installed in the brake housing 62, and rubs against the friction plate 671 on the brake disc 67 to generate a braking force, thereby limiting the rotation of the motor output shaft. The generated axial braking force is first transmitted to the motor through the thrust ball bearing and then to the housing. The power distributor input shaft is connected to the motor shaft through the spline on the brake disc, and the deep groove ball bearing is used to support one end of the power distributor input shaft. Through this design, even if the motor fails, the electromagnetic brake can quickly take effect to ensure the safety and driving ability of the vehicle.

[0040] See also Figure 1 As shown, in the embodiment of the present invention, the wheel assembly 20 includes a wheel 202, a wheel connecting shaft 203 and a wheel fixing frame 205, wherein one end of the wheel connecting shaft 203 is connected to the wheel 202 and is locked by a fixing nut 201, and the other end of the wheel connecting shaft 203 is connected to the output end of the power coupling system 106 through the cross-axis universal joint assembly 108, and the wheel fixing frame 205 is installed on the wheel connecting shaft 203 through a thrust ball bearing III 204, and the thrust ball bearing III 204 is axially limited by an end cover 206 and a clamping nut 208.

[0041] In the embodiment of the present invention, the cantilever assembly 109 includes a connecting shaft I 1091, a connecting shaft II 1093, a lower fork arm 1095, an upper fork arm 1096 and a connecting shaft VI 1097, wherein the upper fork arm 1096 and the lower fork arm 1095 are arranged in parallel on the upper and lower sides of the wheel fixing frame 205, and one end of the upper fork arm 1096 and the lower fork arm 1095 are respectively hinged to the rear support frame 105 and the frame 104 through the connecting shaft I 1091, and at the connecting shaft I 1091, the upper fork arm 1096 and the lower fork arm 1095 are respectively hinged to the rear support frame 105 and the frame 104. The end is axially limited by the shaft retaining spring 1092; the other ends of the upper fork arm 1096 and the lower fork arm 1095 are respectively hinged to the upper and lower sides of the wheel fixing frame 205 through the connecting shaft VI 1097; the other end of the lower fork arm 1095 close to the frame 104 is provided with a connecting shaft II 1093 on both sides, and the connecting shaft II 1093 is used to be hinged to the lower end of the shock-absorbing spring assembly 107; the upper end of the shock-absorbing spring assembly 107 is hinged to the coupling device mounting frame 8 through the connecting shaft III 1094.

[0042] The present invention provides a manned lunar rover based on differential speed coupling drive, wherein both driving motors are high-efficiency permanent magnet synchronous motors of the same power, suitable for the power requirements of the lunar rover, and can be speed-coupled through a coupling device. The working state of the driving motor is adjusted in real time through the differential speed coupling device 3 to ensure the stability of power transmission.

[0043] When the lunar rover is in a flat terrain or low power demand environment, the system will automatically switch to a single motor drive mode to reduce energy consumption and extend working time. The single motor drive mode is to turn off one of the drive motors, and limit the rotation of one of the input shafts by a connected electromagnetic brake, and the power is transmitted from the working drive motor to the wheels through the differential speed coupling device 3 and the secondary reduction device 9; when the lunar rover enters a steep slope or complex terrain, the system will automatically switch to a dual motor drive mode to increase the total power output of the system and enhance the vehicle's climbing ability and passability.

[0044] During the power coupling process of the differential speed coupling device 3 of the present invention, the torques of the two power sources are in a certain proportional relationship with each other, the output speeds are independent of each other, and the final output synthetic speed is the linear superposition of the speeds of the two power sources. When the speed of one power source changes, the speed of the other power source will also change accordingly. Therefore, it is only necessary to fix the speed of one of the drive motors and adjust the speed of the other drive motor to achieve stepless speed change, automatically adjust the vehicle speed under different terrains, and improve sports performance.

[0045] When one of the drive motors cannot be used due to a fault, the electromagnetic brake is activated to lock the corresponding output shaft, limiting the rotation of the output shaft. The other drive motor works alone to transmit power to the wheels through the differential speed coupling device 3 and the secondary reduction device 9, thereby realizing single-motor drive.

[0046] The present invention provides a manned lunar rover based on differential speed coupling drive, wherein the differential speed coupling device 3 realizes speed coupling and power distribution, and has single motor fault tolerance capability, thereby ensuring that the manned lunar rover can still drive safely even when some motors fail, and significantly improving driving safety and passability under complex lunar terrain. The present invention can effectively reduce energy loss in the transmission system, improve the transmission efficiency of the system, and ensure that the lunar rover has stronger adaptability under different terrain conditions.

[0047] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A manned lunar rover based on differential speed coupling drive, characterized in that: The vehicle comprises a vehicle frame (104), a power coupling system (106), a shock absorbing spring assembly (107), a cross-axis universal joint assembly (108), a cantilever assembly (109) and a wheel assembly (20), wherein the power coupling system (106) is arranged on the vehicle frame (104), the output ends on both sides of the power coupling system (106) are respectively connected to two wheel assemblies (20), the wheel assembly (20) is hinged to the vehicle frame (104) through the cantilever assembly (109), two groups of shock absorbing spring assemblies (107) are arranged on both sides of the vehicle frame (104), and the shock absorbing spring assembly (107) is connected to the wheel assembly (20); the power coupling system (106) can realize the switching between a single motor power output mode and a dual motor coupling power output mode.

2. The manned lunar rover based on differential speed coupling drive according to claim 1, characterized in that: The power coupling system (106) comprises a coupling device mounting frame (8), a housing (4), a drive motor I (1), an electromagnetic brake I (2), a differential speed coupling device (3), an electromagnetic brake II (6), a drive motor II (7) and a two-stage reduction device (9) mounted in the housing (4), wherein a drive motor output shaft I (21) of the drive motor I (1) is connected to an input shaft of the differential speed coupling device (3), a drive motor output shaft II (61) of the drive motor II (7) is connected to another input shaft of the differential speed coupling device (3), and the front ends of the drive motor I (1) and the drive motor II (7) are respectively provided with an electromagnetic brake I (2) and an electromagnetic brake II (6) for braking the output shafts; and the output shaft of the differential speed coupling device (3) is connected to the input shaft of the two-stage reduction device (9); The housing (4) is mounted on a coupling device mounting frame (8), and the coupling device mounting frame (8) is connected to the vehicle frame (104).

3. The manned lunar rover based on differential speed coupling drive according to claim 2, characterized in that: The differential speed coupling device (3) comprises a coupling device housing (32), an input bevel gear shaft (332), a driven bevel gear (341), a planetary gear assembly I (35) and two half-shaft bevel gears I (362), wherein the input bevel gear shaft (332) is connected to the output shaft I (21) of the drive motor, the coupling device housing (32) is rotationally connected to the housing (4), the driven bevel gear (341) is fixedly arranged on the outside of the coupling device housing (32), and the driven bevel gear (341) is meshed with the input bevel gear shaft (332), and the drive motor I (1) provides power for the rotation of the coupling device housing (32); The planetary gear assembly I (35) is arranged in a coupling device housing (32); the two half-shaft bevel gears I (362) are rotatably mounted in the coupling device housing (32) with their rotation axes collinear; the two half-shaft bevel gears I (362) are respectively located on both sides of the planetary gear assembly I (35) and are both meshed with the planetary gear assembly I (35); the two half-shaft bevel gears I (362) are respectively connected to the output shaft II (61) of the drive motor and the input shaft of the secondary reduction device (9).

4. The manned lunar rover based on differential speed coupling drive according to claim 3, characterized in that: The planetary gear assembly I (35) comprises a planetary gear shaft I (353) and two planetary gears I (351), wherein the planetary gear shaft I (353) is fixed in the coupling device housing (32), and the axis of the planetary gear shaft I (353) is perpendicular to the axis of the half-shaft bevel gear I (362); the two planetary gears I (351) are rotatably mounted on both ends of the planetary gear shaft I (353) via needle bearings (354), and the backs of the two planetary gears I (351) are connected to the coupling device housing (32) via thrust ball bearings I (352); and the two planetary gears I (351) are meshed with the half-shaft bevel gears I (362) on both sides.

5. The manned lunar rover based on differential speed coupling drive according to claim 2, characterized in that: The secondary reduction device (9) comprises a secondary reduction device output shaft I (91), a secondary reduction device output shaft II (92), an input gear shaft (942), an intermediate gear shaft (944), a driven helical gear (971), a differential housing (99) and a differential planetary gear mechanism, wherein the input gear shaft (942), the intermediate gear shaft (944) and the driven helical gear (971) are rotatably mounted on the housing (4) and meshed in sequence, the input gear shaft (942) is connected to the output shaft of the differential speed coupling device (3); the driven helical gear (971) is fixedly mounted on the differential housing (99), the differential housing (99) is rotatably connected to the housing (4), and the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92) are rotatably mounted on both sides of the differential housing (99), with their axes being collinear; The differential planetary gear mechanism is arranged in the differential housing (99), and the differential planetary gear mechanism is connected to the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92), and the differential planetary gear mechanism is used to distribute power to the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92).

6. The manned lunar rover based on differential speed coupling drive according to claim 5, characterized in that: The differential planetary gear mechanism comprises a planetary gear assembly II (98) and two half-shaft bevel gears II (962), wherein the planetary gear assembly II (98) is arranged in the differential housing (99), and the two half-shaft bevel gears II (962) are rotatably mounted on both sides of the differential housing (99), and the rotation axes are collinear; the two half-shaft bevel gears II (962) are both meshed with the planetary gear assembly II (98), and the two half-shaft bevel gears II (962) are coaxially connected to the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92), respectively; The planetary gear assembly II (98) comprises a planetary gear shaft II (981) and two planetary gears II (982) rotatably mounted at both ends of the planetary gear shaft II (981), and planetary gear gaskets (983) are provided on the backs of the two planetary gears II (982); each planetary gear II (982) is meshed with the half-shaft bevel gears II (962) on both sides.

7. The manned lunar rover based on differential speed coupling drive according to claim 2, characterized in that: The electromagnetic brake I (2) and the electromagnetic brake II (6) have the same structure, and both include a brake housing (62) and an elastic guide assembly, an electromagnet (64), an armature (66) and a brake disc (67) installed in the brake housing (62), wherein the brake housing (62) is rotatably mounted on the output shaft I (21) of the drive motor or the output shaft II (61) of the drive motor, and the brake housing (62) is fixedly connected to the housing (4); the brake disc (67) is connected to the output shaft I (21) of the drive motor or the output shaft II (61) of the drive motor via a spline shaft; The electromagnet (64) is embedded in the inner side of the brake housing (62), the armature (66) is arranged between the electromagnet (64) and the brake disc (67), and the armature (66) is connected to the brake housing (62) through an elastic guide component; when the electromagnet (64) is energized, the armature (66) and the electromagnet (64) are attracted; when the electromagnet (64) is de-energized, the elastic guide component pushes the armature (66) and the brake disc (67) to fit together, thereby achieving braking.

8. The manned lunar rover based on differential speed coupling drive according to claim 2, characterized in that: The wheel assembly (20) comprises a wheel (202), a wheel connecting shaft (203) and a wheel fixing frame (205), wherein one end of the wheel connecting shaft (203) is connected to the wheel (202), and the other end is connected to the output end of the power coupling system (106) via a cross-axis universal joint assembly (108), and the wheel fixing frame (205) is mounted on the wheel connecting shaft (203) via a thrust ball bearing III (204).

9. The manned lunar rover based on differential speed coupling drive according to claim 8, characterized in that: The suspension assembly (109) comprises a connecting shaft I (1091), a connecting shaft II (1093), a lower fork arm (1095), an upper fork arm (1096) and a connecting shaft VI (1097), wherein the upper fork arm (1096) and the lower fork arm (1095) are arranged in parallel at the upper and lower sides of the wheel fixing frame (205), and one end of the upper fork arm (1096) and the lower fork arm (1095) are hinged to the vehicle frame (104) via the connecting shaft I (1091), and the upper fork arm (109 6) and the other end of the lower fork arm (1095) are respectively hinged to the upper and lower sides of the wheel fixing frame (205) through a connecting shaft VI (1097); the other end of the lower fork arm (1095) close to the frame (104) is provided with a connecting shaft II (1093) on both sides, and the connecting shaft II (1093) is used to be hinged to the lower end of the shock absorbing spring assembly (107); the upper end of the shock absorbing spring assembly (107) is hinged to the coupling device mounting frame (8) through a connecting shaft III (1094).

10. The manned lunar rover based on differential speed coupling drive according to claim 1, characterized in that: The vehicle also comprises a front wheel (101), a front wheel shock absorbing system (102), a front support frame (103) and a rear support frame (105), wherein the front support frame (103) and the rear support frame (105) are respectively arranged at the front and rear ends of the vehicle frame (104), and front wheels (101) are arranged on both sides of the front end of the vehicle frame (104), and the front wheels (101) are hinged to the vehicle frame (104) via the front wheel shock absorbing system (102).

Images