A robot chassis and a mowing robot

Abstract

The scheme belongs to the technical field of mowing equipment, and discloses a robot chassis and a mowing robot. The chassis comprises a body and a first wheel set and a second wheel set which are arranged at intervals along a first direction, the first wheel set comprises a first driving wheel and a second driving wheel which are arranged at intervals along a second direction and are rotationally connected to the body, and the second wheel set comprises a third driving wheel and a fourth driving wheel which are arranged at intervals along the second direction and are rotationally connected to the body. The first driving wheel can rotate around a first rotation axis and can turn around a first turning axis, and the second driving wheel can rotate around a second rotation axis and can turn around a second turning axis. The first driving wheel and the second driving wheel which can turn are used to construct a chassis configuration of all-wheel drive and turning, realize the organic combination of all-wheel drive and turning ability, and make the chassis have high traction, high obstacle crossing, high mobility and low abrasion, and can well adapt to the increasing performance requirements of the chassis in complex and unstructured environments.

Description

Technical Field

[0001] This solution belongs to the field of lawn mowing equipment technology, specifically involving a robot chassis and a lawn mowing robot. Background Technology

[0002] The "two-wheel drive + omnidirectional wheel" chassis configuration commonly used in commercial lawnmowers has become a technological paradigm in the field of automated garden maintenance. This configuration typically manifests as a combination of front-wheel drive with rear omnidirectional wheels, or rear-wheel drive with front omnidirectional wheels. Its core feature is that it only uses two drive motors for power, supplemented by small-diameter omnidirectional wheels for support and steering. Although this design has certain advantages in control logic and manufacturing costs, its inherent structural limitations are becoming increasingly apparent in practice, especially in unstructured and complex terrain, becoming a technical bottleneck restricting the improvement of operational efficiency.

[0003] The primary limitation lies in the overall traction performance of the machine. Since only 50% of the wheel sets have driving force, the overall adhesion coefficient and maximum propulsion are fundamentally restricted. When the equipment faces grassy slopes with an angle exceeding 15 degrees, slippery grass soaked with morning dew, or areas with soft soil, the ground pressure and shear force provided by the two drive wheels alone are often insufficient to overcome the resistance. In such situations, the drive wheels are prone to slipping and spinning, and the swivel wheels, as passive driven wheels, not only fail to provide effective traction, but their tendency to sink on soft surfaces also creates additional obstacles, causing the equipment to become stuck and forcibly interrupting the continuity of operations.

[0004] Secondly, this configuration has a significant weakness in obstacle-crossing capability. The small-diameter omnidirectional wheels, designed for flexible steering, naturally have limited physical dimensions and ground clearance, resulting in extremely limited ability to roll over obstacles. In actual garden environments, common obstacles such as exposed gravel, protruding tree roots, or scattered broken branches can easily exceed the effective passing radius of the omnidirectional wheels. Once the omnidirectional wheels come into contact with an obstacle, they are very likely to get stuck and lock up, causing the entire chassis system to instantly lose its steering freedom. At this point, the power output of the drive wheels not only fails to help get out of trouble, but may also cause local turf damage and energy waste due to continuous spinning, and may even lead to the risk of motor overload.

[0005] When performing complex boundary trimming, tree circling operations, or navigating narrow courtyard passages, the limited steering angle forces the equipment to perform multiple cumbersome "forward-turn-reverse" maneuvers to complete path tracking. This discontinuous, step-by-step movement pattern not only significantly reduces operational efficiency and increases energy consumption, but the unevenness of its trajectory can also cause unnecessary crushing of the lawn edges.

[0006] A deeper problem lies in the fact that this rigid connection and non-all-wheel-drive configuration result in a lack of adaptability and dynamic stability for the entire machine in the face of continuously changing terrain. When driving on lawns with slight potholes or undulations, the vehicle's posture will produce unexpected bumps and swaying due to the passive response of the omnidirectional wheels. This unstable motion directly affects the constant distance between the mowing blade and the turf, leading to uneven mowing height and reduced work quality. On the other hand, continuous non-uniform load impacts will also accelerate the fatigue wear of the mechanical structure and interfere with the data accuracy of onboard sensors (such as IMU and GPS antennas), affecting the reliability of the navigation system. Utility Model Content

[0007] This solution aims to overcome at least one deficiency in the existing technology and provide a robot chassis to solve the problems of insufficient driving force and obstacle crossing ability of traditional chassis.

[0008] To solve the above-mentioned technical problems, the following technical solution is adopted: In a first aspect, a robot chassis is proposed. The chassis includes a body and a first wheel set and a second wheel set spaced apart along a first direction; the first wheel set includes a first drive wheel and a second drive wheel spaced apart along a second direction and rotatably connected to the body, the first drive wheel being able to rotate around a first rotation axis and be able to turn around a first steering axis, the second drive wheel being able to rotate around a second rotation axis and be able to turn around a second steering axis, the first steering axis and the second steering axis being parallel to a third direction; the second wheel set includes a third drive wheel and a fourth drive wheel spaced apart along the second direction and rotatably connected to the body, the third drive wheel being able to rotate around a third rotation axis, the fourth drive wheel being able to rotate around a fourth rotation axis, the third rotation axis and the fourth rotation axis always being parallel to the second direction; the first direction, the second direction and the third direction are perpendicular to each other.

[0009] This chassis features an all-wheel drive and steering configuration achieved through the steerable first and second drive wheels. This combination of all-wheel drive and steering capabilities results in high traction, excellent obstacle clearance, high maneuverability, and low wear, effectively meeting the increasing performance demands of complex and unstructured environments. Drive force is evenly distributed to all four contact points, providing uniform and strong traction. When facing slopes, slippery or soft surfaces, temporary slippage of a single drive wheel can be compensated for by the power output of the other three drive wheels, ensuring strong and stable passability. Climbing ability is increased to over 30°. When encountering obstacles such as exposed gravel, protruding tree roots, or scattered branches, the large diameter of the drive wheels prevents them from getting stuck, allowing it to traverse obstacles over 80mm in height and adapt to terrains such as steps and potholes. The steering capabilities of the first and second drive wheels give the chassis high maneuverability. Steering can be achieved without a large linear speed difference between the first and second wheel sets. When the chassis is steering, the first drive wheel can rotate in a direction tangent to its trajectory, and the second drive wheel can rotate in a direction tangent to its trajectory. This makes the friction between the first and second drive wheels and the ground primarily rolling friction, with almost no sliding friction, effectively reducing or even eliminating damage to turf and other ground cover caused by steering.

[0010] The third and fourth rotation axes are always parallel to the second direction, which simplifies the structure of the second wheel set and allows it to work in conjunction with the first wheel set. While ensuring excellent maneuverability, it significantly improves the stability and reliability of the system and reduces the complexity of control. No matter how complex the steering maneuver of the first wheel set is, the second wheel set always provides a driving force reference that is fixed to the main body and has a constant direction, which greatly simplifies the kinematic inverse calculation and control command generation in straight-line driving and most conventional curved driving conditions.

[0011] The first drive wheel steers around the first steering axis, and the second drive wheel steers around the second steering axis, preferably independently, to provide the chassis with a wider range of motion modes. In scenarios requiring high maneuverability, such as turning around in narrow spaces or traveling along complex curved paths, the two drive wheels of the first wheel set can deflect in the same direction (achieving Ackerman steering, and the chassis's steering center can be freely adjusted along the extension line connecting the centers of the third and fourth drive wheels, without being confined to a specific point on that extension line), or they can deflect in opposite directions (achieving on-the-spot turning). This flexible steering mechanism allows the chassis's minimum turning radius to approach zero, further improving the chassis's maneuverability, achieving near-omnidirectional motion capability, and significantly enhancing the machine's ability to get out of trouble.

[0012] The chassis preferably includes a first part near the first wheel set and a second part near the second wheel set. The first part is T-shaped and includes a longitudinal segment parallel to the first direction and a transverse segment parallel to the second direction. One end of the longitudinal segment connects to the middle of the transverse segment, and the other end connects to the second part. The first steering shaft and the second steering shaft are located at the two ends of the transverse segment, respectively. The difference in width between the transverse segment and the longitudinal segment in the second direction is preferably 0.8 to 1.2 times the diameter of the first drive wheel / second drive wheel. Space is left between the transverse segment and the second part for the first drive wheel / second drive wheel to turn, significantly reducing the interference of the chassis on the steering of the drive wheels. Therefore, when performing Ackermann steering, the chassis steering center located on the extension line connecting the centers of the third drive wheel and the fourth drive wheel can be infinitely far away from the third drive wheel / fourth drive wheel, infinitely close to the third drive wheel / fourth drive wheel, or even coincide with the third drive wheel / fourth drive wheel, further improving the steering flexibility and maneuverability of the chassis. Moreover, it allows for the installation of larger diameter drive wheels without raising the overall chassis center of gravity, thereby increasing the chassis's ground clearance and enhancing its ability to cross obstacles, thus improving the overall mobility of the machine.

[0013] The first drive wheel is driven by the first steering mechanism to steer around the first steering axis, and the second drive wheel is driven by the second steering mechanism to steer around the second steering axis. The projections of the first and second steering mechanisms onto the normal plane in the third direction lie within the projection range of the lateral segment onto the normal plane in the third direction. Therefore, by directly and independently assigning values ​​to the front wheel steering angle, decoupling it from the speed control of the drive wheels can be achieved, resulting in richer and more precise motion synthesis. The control system can calculate the optimal deflection angle and speed required for each front / rear wheel in real time according to the preset path planning and execute it rapidly through the highly responsive steering mechanism. This direct control eliminates steering lag and trajectory errors present in passive systems, enabling the chassis to strictly track any predetermined path, including complex curves. This greatly improves the operational accuracy required for high-end applications and avoids unnecessary crushing of ground cover caused by multiple cumbersome "forward-steering-reverse" operation combinations.

[0014] The first part of the T-shape is configured to allow the steering angles of the first and second drive wheels to be continuously and independently adjusted between maximum reverse deflection and maximum unidirectional deflection, so that the instantaneous steering center (A) of the robot chassis can be continuously located at different positions on the extension line connecting the centers of the third and fourth drive wheels.

[0015] The first steering mechanism includes a first steering shaft, and the second steering mechanism includes a second steering shaft. The first and / or second steering shafts preferably include an outer shaft and an inner shaft that are nested together and can only slide axially relative to each other. A compression spring is fitted onto the inner shaft between the lower ends of the outer and inner shafts. When the first or second drive wheel crosses an obstacle and experiences an impact force exceeding the preload of the compression spring, relative axial sliding will occur between the inner and outer shafts, further compressing the compression spring. This effectively converts the sharp impact into the storage and release of the spring's potential energy, establishing a reliable mechanical barrier for upstream precision transmission components (gear sets, motors), and improving the steering mechanism's impact resistance.

[0016] An origin detection component is also provided between the first steering shaft and / or the second steering shaft and the main body. The origin detection component includes an origin detection plate installed on the first steering shaft and / or the second steering shaft and an origin detector installed on the main body. This allows for the rapid and accurate location of the mechanical zero position of the steering mechanism during initialization, establishing an absolute position coordinate reference for the entire steering control system. This not only eliminates the risk of cumulative steering angle errors and ensures that the starting point of each steering action is accurately known, but more importantly, it enables the control system to continuously monitor and calibrate the actual angular position of the drive wheels, comparing and correcting it in real time with the command value. This effectively combats angle drift that may be caused by factors such as gear wear, load changes, or external impacts, fundamentally ensuring the long-term repeatability accuracy and reliability of the steering angle. This allows precise algorithms such as the Ackerman steering geometry model to be faithfully and stably executed on the chassis.

[0017] The lower side of the main body is provided with a serrated first protective cover and a second protective cover. The first protective cover and the second protective cover are spaced apart in the first direction. The first rotating shaft, the second rotating shaft, the third rotating shaft and the fourth rotating shaft are located between the first protective cover and the second protective cover. While ensuring that the grass will not be blocked and missed cutting will occur, the shaft prevents people from reaching into the bottom of the machine to touch the blades of the cutting module, thus reducing safety hazards.

[0018] Secondly, a lawn mowing robot is proposed. The lawn mowing robot includes a cutting module, a battery, and the aforementioned robot chassis. The main body of the robot chassis has a downward-facing working compartment and a battery compartment. The cutting module is installed in the working compartment, and the battery is installed in the battery compartment.

[0019] This lawnmower robot uses the aforementioned robot chassis, which has an all-wheel drive and steering configuration through a first and second drive wheel that can turn. This achieves an organic combination of all-wheel drive and steering capabilities, giving the chassis high traction, high obstacle crossing ability, high mobility and low wear, and enabling it to adapt well to the increasing performance requirements of the chassis in complex and unstructured environments.

[0020] Compared with existing technologies, this solution has the following advantages: by constructing an all-wheel drive and steering chassis configuration through the first and second drive wheels that can be steered, it achieves an organic combination of all-wheel drive and steering capabilities, enabling the chassis to have high traction, high obstacle crossing ability, high maneuverability and low wear, and can well adapt to the increasing performance requirements of the chassis in complex and unstructured environments. Attached Figure Description

[0021] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this solution. To better illustrate the solution, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0022] Figure 1 This is a top-view diagram of the chassis.

[0023] Figure 2 This is a schematic diagram of the chassis from the bottom.

[0024] Figure 3 This is a schematic diagram of the chassis turning in place around its geometric center.

[0025] Figure 4 This is a schematic diagram of the chassis turning in place around a point on the line connecting the centers of the third and fourth drive wheels.

[0026] Figures 5-6 This is a schematic diagram of Ackermann steering around a point on the extended line connecting the centers of the third and fourth drive wheels.

[0027] Figure 7 It is the chassis that is being carried out. Figure 5 The diagram shows the three-dimensional state of Ackermann during steering.

[0028] Figure 8 It is the chassis that is being carried out. Figure 6 The diagram shows the three-dimensional state of Ackermann during steering.

[0029] Figure 9 This is a top view of the chassis. Figure 10 This is a partial sectional view of the chassis.

[0030] Figure 11 yes Figure 10 A magnified view of a portion of the image.

[0031] Figure 12 This is a partial exploded view of the chassis.

[0032] Figure 13 yes Figure 12 A magnified view of a portion of the image.

[0033] Explanation of reference numerals in the attached drawings: Body 100, First part 110, Horizontal section 111, Vertical section 112, Second part 120, Working compartment 121, Battery compartment 122, Limiting rib 140, Origin detector 150, First drive wheel 201, Second drive wheel 202, Third drive wheel 203, Fourth drive wheel 204, Hub motor 300, First rotating shaft 301, Second rotating shaft 302, Third rotating shaft 303, Fourth rotating shaft 304, First steering mechanism 401, Second steering mechanism 402, Motor 410, Gear set 420, First steering shaft 4301, Second steering shaft 4302, Outer shaft 431, Inner shaft 432, Limiting sleeve 433, Limiting piece 434, Limiting block 440, Origin detection piece 450, Compression spring 460, First protective cover 501, Second protective cover 502, First direction X, Second direction Y, Third direction Z, Steering center A. Detailed Implementation

[0034] To enable those skilled in the art to better understand this solution, the following detailed description is provided in conjunction with specific embodiments.

[0035] Figures 1-13 The diagram illustrates a robot chassis having a first direction, a second direction, and a third direction that are perpendicular to each other. The first direction and the second direction are located in the same plane, and the third direction is perpendicular to the plane containing the first direction and the second direction.

[0036] like Figures 1-2 As shown, the chassis includes a body 100, a first wheel set, and a second wheel set. The first wheel set includes a first drive wheel 201 and a second drive wheel 202, and the second wheel set includes a third drive wheel 203 and a fourth drive wheel 204. The chassis has four wheels, all of which are drive wheels, forming an all-wheel drive system. The driving force is evenly distributed to all four contact points, giving the chassis uniform and strong traction. When facing slopes, slippery or soft surfaces, the brief slippage of a single drive wheel can be compensated by the power output of the other three drive wheels, thus ensuring strong and stable passability and increasing the climbing ability to over 30°. The drive wheels often have a large diameter. When facing obstacles such as exposed gravel, protruding tree roots, or scattered branches, the large diameter of the drive wheels makes them less prone to jamming, enabling them to cross obstacles with a height exceeding 80mm and adapt to terrain such as steps and potholes. Since all four wheels are drive wheels, the chassis can be turned in place around its geometric center by controlling the four drive wheels to rotate at the same speed, with the first drive wheel 201 and the third drive wheel 203 rotating in the same direction and opposite to the rotation direction of the second drive wheel 202 and the fourth drive wheel 204. Figure 3 As shown. The drive wheels can be powered by a hub motor 300 located inside them.

[0037] like Figure 2 As shown, the first and second wheel sets are spaced apart along a first direction, the first drive wheel 201 and the second drive wheel 202 are spaced apart along a second direction, and the third drive wheel 203 and the fourth drive wheel 204 are spaced apart along a second direction. The first drive wheel 201, the second drive wheel 202, the third drive wheel 203, and the fourth drive wheel 204 are rotatably connected to the body 100. The first drive wheel 201 can rotate around the first rotation axis 301, the second drive wheel 202 can rotate around the second rotation axis 302, the third drive wheel 203 can rotate around the third rotation axis 303, and the fourth drive wheel 204 can rotate around the fourth rotation axis 304. The first and second rotation axes 301 and 302 are parallel to the second direction during straight-line travel, and the third and fourth rotation axes 303 and 304 are parallel to the second direction during straight-line travel. This ensures that all wheels have a synchronized linear speed during straight-line travel, effectively avoiding internal power circulation loss and unnecessary tire wear caused by wheel speed differences, and preventing damage to turf and other ground coverings.

[0038] The first rotating shaft 301, the second rotating shaft 302, the third rotating shaft 303, and the fourth rotating shaft 304 can be collectively referred to as rotating shafts. Besides rotating around these shafts, the first drive wheel 201 can also turn around the first steering shaft 4301, and the second drive wheel 202 can also turn around the second steering shaft 4302. The first steering shaft 4301 and the second steering shaft 4302 are parallel to the third direction, giving the chassis high maneuverability and allowing steering without requiring a larger linear speed difference between the first and second wheel sets. When the chassis is steering, the first drive wheel 201 can rotate in a direction tangent to its trajectory, and the second drive wheel 202 can rotate in a direction tangent to its trajectory. This ensures that the friction between the first and second drive wheels 201 and the ground is primarily rolling friction, with almost no sliding friction, effectively reducing or even eliminating damage to turf and other ground cover caused by steering.

[0039] The aforementioned chassis, through the first drive wheel 201 and the second drive wheel 202 capable of steering, constructs an all-wheel drive and steering chassis configuration, achieving an organic combination of all-wheel drive and steering capabilities. This enables the chassis to possess high traction, high obstacle-crossing ability, high maneuverability, and low wear, and can well adapt to the increasing performance requirements of the chassis in complex and unstructured environments.

[0040] When the first drive wheel 201 and the second drive wheel 202 turn around their respective steering axes, the first rotation axis 301 and the second rotation axis 302 also turn accordingly. Therefore, the first rotation axis 301 and the second rotation axis 302 are no longer located on the same straight line parallel to the second direction during the turning process. Unlike the first wheel set, the third rotation axis 303 and the fourth rotation axis 304 can always be parallel to the second direction. That is, the third drive wheel 203 and the fourth drive wheel 204 are directional drive wheels, relatively fixed except for their own rotation. This simplifies the structure of the second wheel set and allows it to cooperate with the first wheel set. While ensuring excellent maneuverability, it significantly improves the stability and reliability of the system and reduces the complexity of control. Regardless of how complex the steering maneuver of the first wheel set is, the second wheel set always provides a driving force reference that is fixed to the main body 100 and has a constant direction, greatly simplifying the inverse kinematics calculation and control command generation under straight-line driving and most conventional curved driving conditions.

[0041] The steering of the first drive wheel 201 around the first steering shaft 4301 and the steering of the second drive wheel 202 around the second steering shaft 4302 can be performed independently, thus giving the chassis a richer range of motion modes. In scenarios requiring high maneuverability, such as turning around in a narrow space or traveling along a complex curved path, the two drive wheels of the first wheel set can perform opposite deflections (achieving on-the-spot steering, such as...). Figure 4 It can also perform unidirectional deflection (achieving Ackermann steering, and the chassis steering center can be freely adjusted along the extension line connecting the centers of the third drive wheel 203 and the fourth drive wheel 204, without being restricted to a specific point on that extension line, such as...) Figures 5-6 This flexible steering mechanism allows the chassis's minimum turning radius to approach zero, further improving the chassis's maneuverability, achieving near omnidirectional movement capability, and significantly enhancing the machine's ability to get out of trouble.

[0042] like Figures 7-9As shown, the body 100 can be divided into a first part 110 and a second part 120. The first part 110 is close to the first wheel set, and the second part 120 is close to the second wheel set. The first part 110 can be configured in a T-shape, including a longitudinal segment 112 parallel to the first direction and a transverse segment 111 parallel to the second direction. One end of the longitudinal segment 112 connects to the middle of the transverse segment 111, and the other end connects to the second part 120. The first steering shaft 4301 and the second steering shaft 4302 are located at the two ends of the transverse segment 111, respectively. The T-shaped structural design provides space between the transverse segment 111 and the second part 120 for the first drive wheel 201 / second drive wheel 202 to turn. Especially when the difference in width between the transverse segment 111 and the longitudinal segment 112 in the second direction is 0.8 to 1.2 times the diameter of the first drive wheel 201 / second drive wheel 202, the interference of the body 100 on the steering of the drive wheels is significantly reduced. Therefore, during Ackermann steering, the chassis steering center, located on the extension line of the line connecting the centers of the third drive wheel 203 and the fourth drive wheel 204, can be infinitely far away from the third drive wheel 203 / fourth drive wheel 204, or infinitely close to the third drive wheel 203 / fourth drive wheel 204, or even coincide with the third drive wheel 203 / fourth drive wheel 204 (e.g., Figure 6 This further enhances the chassis's steering flexibility and maneuverability. Moreover, it allows for the installation of larger diameter drive wheels without raising the overall chassis center of gravity, thereby increasing the chassis's ground clearance and further enhancing its ability to traverse obstacles, thus improving the overall mobility of the machine. The first part of the T-shape is constructed to allow the steering angles of the first and second drive wheels to be continuously and independently adjusted between maximum reverse deflection and maximum unidirectional deflection, thereby enabling the instantaneous steering center (A) of the robot chassis to be continuously located at different positions on the extension line connecting the centers of the third and fourth drive wheels.

[0043] The second part 120 of the main body 100 can be configured as a rectangle to increase the installation space of the main body 100. Specifically, a downward-facing working compartment 121 and a battery compartment 122 can be provided in the second part 120 to accommodate a cutting module for mowing and a battery for providing power. Figure 2 As shown, the battery compartment 122 can be configured between the third drive wheel 203 and the fourth drive wheel 204. This position, close to the edge of the main body 100, facilitates battery replacement or charging. The working compartment 121 can be configured between the first and second wheel sets, away from the drive wheels, which is more conducive to mowing. The combination of T-shape and rectangle allows the main body 100 to be configured as a box-like structure with an open top, separating the cutting module from other structures to prevent grass clippings generated during mowing from contaminating other structures and affecting their normal operation.

[0044] The steering of the first drive wheel 201 around the first steering shaft 4301 can be driven by the first steering mechanism 401, and the steering of the second drive wheel 202 around the second steering shaft 4302 can be driven by the second steering mechanism 402. In other words, the first drive wheel 201 and the second drive wheel 202 will actively steer according to the steering requirements of the chassis, rather than passively steer following the driving trajectory after a change in the driving trajectory. This means that the direction of chassis movement is no longer indirectly and coupled by adjusting the speed difference between the left and right wheels, but can be decoupled from the speed control of the drive wheels by directly and independently assigning values ​​to the steering angle of the front wheels, thereby achieving richer and more precise motion synthesis. The control system can calculate the optimal deflection angle and speed required for each front / rear wheel in real time according to the preset path planning, and execute it quickly through the high-response steering mechanism. This direct control eliminates steering lag and trajectory errors present in passive systems, enabling the chassis to strictly track any predetermined path, including complex curves. This greatly improves the operational accuracy required for high-end applications and avoids unnecessary crushing of ground cover caused by multiple tedious "forward-turning-reverse" operation combinations.

[0045] The first steering mechanism 401 and the second steering mechanism 402 can be collectively referred to as steering mechanisms. The projection of the steering mechanism onto the normal plane in the third direction lies within the projection range of the transverse segment 111 onto the normal plane in the third direction. Figure 9 As shown, this is to avoid interfering with the steering of the drive wheels, so as to make full use of the steering space provided to the drive wheels by the T-shaped body 100 of the first part 110.

[0046] The first steering shaft 4301 and the second steering shaft 4302 can be collectively referred to as steering shafts, which can be components of the steering mechanism. For example... Figures 10-11As shown, the steering mechanism includes a motor 410, a gear set 420, and a steering shaft connected in sequence. The steering shaft is connected to a first rotating shaft 301 or a second rotating shaft 302. The first rotating shaft 301 and the second rotating shaft 302 are respectively connected to a first drive wheel 201 and a second drive wheel 202. The gear set 420 drives the steering shaft to rotate under the drive of the motor 410, thereby causing the corresponding rotating shaft and drive wheel to turn. A limit block 440 is connected to the rotating shaft. The motor 410, gear set 420, and limit block 440 are all located on the upper side of the body 100 (i.e., inside the box-type body 100). The steering shaft penetrates the body 100, with the upper part of the steering shaft located on the upper side of the body 100 and the lower part located on the lower side of the body 100 and connected to the first rotating shaft 301 or the second rotating shaft 302. The limit block 440 restricts the axial movement of the rotating shaft, allowing the rotating shaft connected to the steering shaft and the drive wheel connected to the rotating shaft to be steerably suspended from the body 100. The limiting block 440 and the steering shaft can restrict their relative rotation. The inner wall of the body 100 can also be equipped with a limiting rib 140, which cooperates with the limiting block 440 to limit the rotation angle of the steering shaft, thereby preventing the drive wheel from over-steering and colliding with the body 100.

[0047] like Figures 12-13 As shown, an origin detection component can also be configured between the rotating shaft and the body 100. The origin detection component includes a cooperating origin detection plate 450 and an origin detector 150. The origin detection plate 450 is connected to the rotating shaft, and the origin detector 150 is connected to the body 100. This allows the mechanical zero position of the steering mechanism to be found quickly and accurately during the initialization process, establishing an absolute position coordinate reference for the entire steering control system. This not only eliminates the risk of cumulative steering angle errors and ensures that the starting point of each steering action is accurately known, but more importantly, it enables the control system to continuously monitor and calibrate the actual angle position of the drive wheels, compare and correct it with the command value in real time, thereby effectively combating angle drift that may be caused by factors such as gear wear, load changes or external impacts. This fundamentally ensures the long-term repeatability accuracy and reliability of the steering angle, allowing precise algorithms such as the Ackerman steering geometry model to be faithfully and stably executed on the chassis.

[0048] like Figures 10-11As shown, the steering shaft can be configured as a two-section structure, consisting of an outer shaft 431 and an inner shaft 432. The outer shaft 431 and the inner shaft 432 are nested together and can only slide axially relative to each other, ensuring that there is no relative circumferential rotation between the outer shaft 431 and the inner shaft 432. This ensures that the torque output by the gear set 420 can be transmitted to the drive wheel through the outer shaft 431 and the inner shaft 432. The upper part of the outer shaft 431 is connected to the gear set 420, and the lower part of the outer shaft 431 is nested with the upper part of the inner shaft 432. The lower part of the inner shaft 432 is connected to the rotating shaft, and the inner shaft 432 is fitted with a compression spring 460, which is located between the lower end of the outer shaft 431 and the lower end of the inner shaft 432 (i.e., the lower end of the outer shaft 431 and the rotating shaft). When the first drive wheel 201 or the second drive wheel 202 crosses an obstacle and experiences an impact force exceeding the preload of the compression spring 460, relative axial sliding will occur between the inner shaft 432 and the outer shaft 431. The compression spring 460 will be further compressed, effectively converting the sharp impact into the storage and release of the potential energy of the compression spring 460. This establishes a reliable mechanical barrier for the upstream precision transmission components (gear set 420, motor 410), improving the impact resistance of the steering mechanism. The lower end of the outer shaft 431 can be equipped with a limiting sleeve 433 with a through hole, and the upper end of the inner shaft 432 can be equipped with a limiting member 434. The diameter of the limiting member 434 is larger than the hole diameter of the limiting sleeve 433, preventing the inner shaft 432 from sliding out of the outer shaft 431 and ensuring that the inner shaft 432 and the outer shaft 431 are always connected.

[0049] like Figure 2 As shown, a first protective cover 501 and a second protective cover 502 can be configured on the lower side of the main body 100. The first protective cover 501 and the second protective cover 502 are spaced apart in a first direction, and a first rotating shaft 301, a second rotating shaft 302, a third rotating shaft 303, and a fourth rotating shaft 304 are located between the first protective cover 501 and the second protective cover 502. Both protective covers are serrated, which on the one hand can prevent a person's hand from reaching into the bottom of the machine and touching the blades of the cutting module, reducing safety hazards, and on the other hand can ensure that the protective covers do not obstruct the grass and prevent missed cutting.

[0050] The aforementioned robot chassis can be applied to lawnmower robots. Lawnmower robots are typically equipped with a cutting module and a battery. The cutting module can be installed in the working compartment 121 of the chassis body 100, while the battery can be installed in the battery compartment 122 of the chassis body 100. Two cutting modules can be configured, or a dual-blade structure can be used to improve mowing efficiency. Both dual-cutting modules and dual-blade structures can be configured in the same working compartment 121. For lawnmower robots equipped with dual cutting modules, the body 100 can also be configured with two working compartments 121, each housing one cutting module. The working compartments 121 and their corresponding cutting modules can be arranged side-by-side or staggered.

[0051] Obviously, the above embodiments of this solution are merely examples for clearly illustrating this solution, and are not intended to limit the implementation of this solution. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this solution should be included within the scope of protection of the claims of this solution.

Claims

1. A robot chassis, characterized in that, The chassis includes ontology; The first and second wheel groups are spaced apart along the first direction; The first wheel set includes a first drive wheel and a second drive wheel that are spaced apart along a second direction and rotatably connected to the body. The first drive wheel can rotate around a first rotation axis and can turn around a first steering axis. The second drive wheel can rotate around a second rotation axis and can turn around a second steering axis. The first steering axis and the second steering axis are parallel to a third direction. The second wheel set includes a third drive wheel and a fourth drive wheel that are spaced apart along the second direction and rotatably connected to the body. The third drive wheel is capable of rotating around a third rotation axis, and the fourth drive wheel is capable of rotating around a fourth rotation axis. The third rotation axis and the fourth rotation axis are always parallel to the second direction. The first direction, the second direction, and the third direction are perpendicular to each other.

2. The robot chassis according to claim 1, characterized in that, The first drive wheel turns around the first steering axis, and the second drive wheel turns around the second steering axis, each independently.

3. The robot chassis according to claim 1, characterized in that, The body includes a first part near the first wheel set and a second part near the second wheel set. The first part is T-shaped and includes a longitudinal segment parallel to the first direction and a transverse segment parallel to the second direction. One end of the longitudinal segment is connected to the middle of the transverse segment, and the other end is connected to the second part. The first steering shaft and the second steering shaft are located at the two ends of the transverse segment, respectively.

4. The robot chassis according to claim 3, characterized in that, The difference in width between the horizontal segment and the vertical segment in the second direction is 0.8 to 1.2 times the diameter of the first drive wheel / second drive wheel.

5. The robot chassis according to claim 3 or 4, characterized in that, The first drive wheel is driven by the first steering mechanism to turn around the first steering axis, and the second drive wheel is driven by the second steering mechanism to turn around the second steering axis. The projections of the first steering mechanism and the second steering mechanism on the third-direction normal plane are located within the projection range of the transverse segment on the third-direction normal plane.

6. The robot chassis according to claim 3 or 4, characterized in that, The first part of the T-shape is configured to allow the steering angles of the first and second drive wheels to be continuously and independently adjusted between maximum reverse deflection and maximum unidirectional deflection, thereby enabling the instantaneous steering center (A) of the robot chassis to be continuously located at different positions on the extension line connecting the centers of the third and fourth drive wheels.

7. The robot chassis according to claim 5, characterized in that, The first steering mechanism includes the first steering shaft, the second steering mechanism includes the second steering shaft, and the first steering shaft and / or the second steering shaft includes an outer shaft and an inner shaft that are nested together and can only slide axially relative to each other, and a compression spring is sleeved on the inner shaft between the lower end of the outer shaft and the lower end of the inner shaft.

8. The robot chassis according to claim 7, characterized in that, An origin detection component is further provided between the first steering shaft and / or the second steering shaft and the body. The origin detection component includes an origin detection plate installed on the first steering shaft and / or the second steering shaft and an origin detector installed on the body.

9. The robot chassis according to claim 1 or 2, characterized in that, The lower side of the main body is provided with a serrated first protective cover and a second protective cover, which are spaced apart in a first direction. The first rotating shaft, the second rotating shaft, the third rotating shaft and the fourth rotating shaft are located between the first protective cover and the second protective cover.

10. A lawnmower robot, characterized in that, The lawnmower robot includes a cutting module, a battery, and a robot chassis as described in any one of claims 1 to 9. The main body is provided with a working compartment and a battery compartment with the opening facing downwards. The cutting module is installed in the working compartment, and the battery is installed in the battery compartment.

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