A wheel-foot following robot based on similar linkages
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YANSHAN UNIV
- Filing Date
- 2026-05-14
- Publication Date
- 2026-06-12
Smart Images
Figure CN122186308A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of robotics technology, specifically a wheel-legged following robot based on similar linkages. Background Technology
[0002] Currently, robots have become core operational equipment in unstructured scenarios such as field inspections, emergency search and rescue, disaster exploration, and inspections of complex industrial plant areas.
[0003] Traditional wheeled robots rely on continuous ground support, resulting in poor terrain adaptability and weak obstacle-crossing ability. Limited by fixed wheel diameter and rigid structure, they cannot cross obstacles such as steps and ditches. Once they tip over or fall over, these robots usually cannot right themselves and are prone to failure due to getting stuck in complex terrain. While legged robots improve terrain adaptability through multi-joint bionic gait, the large number of joints and complex motion calculations result in low speed, high energy consumption, and poor transmission efficiency on flat ground. At the same time, the joints are subjected to large load impacts for a long time, making the components prone to wear. Disassembly and maintenance in the field are difficult, making it difficult to meet the requirements of long-term, high-intensity following operations.
[0004] Furthermore, a Chinese utility model patent with publication number CN222611284U discloses a wheeled-legged robot. It uses radar and ultrasonic sensors to perceive road conditions and, combined with multi-motor coordinated control of the thigh, lower leg, and adjustment components, can switch between wheeled and legged movement, achieving a balance between efficiency on flat surfaces and the ability to overcome small obstacles to some extent. However, limited by its single-leg swing and segmented switching motion logic, this robot's obstacle-crossing ability is only suitable for low obstacles such as steps and small stones. When faced with obstacles wider than its leg length, such as ditches, piles of rubble, or large rocks, it cannot actively jump over them and can only detour or stop. Additionally, in mixed terrain with alternating gravel and hard surfaces, frequent starts, stops, and switches disrupt the continuity of movement, leading to interruptions in the following trajectory and reduced operational efficiency, making it difficult to meet the requirements for real-time following and continuous passage.
[0005] Therefore, this application provides a wheel-legged following robot based on similar linkages to solve the above problems. Summary of the Invention
[0006] This application provides a wheeled-legged following robot based on similar linkages, aiming to solve the problems mentioned in the background art, such as insufficient terrain adaptation and obstacle crossing ability, poor autonomous escape, discontinuous movement, inconvenient maintenance, and difficulty in meeting the needs of efficient and stable following operations in unstructured scenarios.
[0007] To achieve the above objectives, this application provides the following technical solution: a wheel-legged following robot based on similar linkages, comprising a frame and wheel-legged actuators respectively disposed on both sides of the frame;
[0008] The wheel-leg actuator includes a hip joint axis mounted on the frame for 360° rotational support, a thigh rod mounted on the hip joint axis, a knee joint axis mounted on the hip joint axis for relative rotation of the thigh and lower leg, a lower leg rod mounted on the knee joint axis, a similar linkage assembly hinged between the thigh rod and lower leg rod for leg movement synchronization, a drive assembly mounted on the frame for driving the hip joint axis and knee joint axis to rotate, a wheeled walking assembly mounted on the similar linkage assembly for rolling motion, and a nitrogen spring mounted on the thigh rod and similar linkage assembly for gravity compensation and posture buffering.
[0009] The wheeled-legged following robot also includes a control system, a laser rangefinder fixedly mounted on the frame for detecting the distance to obstacles ahead, a magnetic sensor for detecting the vehicle's orientation, and an attitude perception module for measuring acceleration and angular velocity. The laser rangefinder, magnetic sensor, and attitude perception module are all connected to the input of the control system, and the drive assembly and wheeled walking assembly are all connected to the output of the control system. Through the coordinated work of the frame, wheel-leg actuators, hip joint axle system, knee joint axle system, similar linkage assembly, drive assembly, wheeled walking assembly, nitrogen spring, attitude perception module, and control system, the wheeled-legged movement is seamlessly integrated, ensuring continuous movement without trajectory interruption. It can autonomously flip over and rescue itself by relying on symmetrical linkage, avoiding failure due to being trapped in complex terrain. With the help of nitrogen spring, it can achieve gravity compensation, energy storage, and instantaneous jumping to overcome obstacles, effectively crossing wide ditches and large rocks. At the same time, it reduces the static load of the drive assembly and improves endurance, fully meeting the needs of long-term, high-intensity following operations in unstructured scenarios such as field inspection, emergency search and rescue, disaster exploration, and inspection of complex industrial plant areas.
[0010] Preferably, to achieve high rigidity and lightweight, the frame includes a grid-shaped skeleton, reinforcing carbon plates fixedly mounted on the grid-shaped skeleton, cutouts in the grid-shaped skeleton and reinforcing carbon plates, and threaded interfaces on both sides of the grid-shaped skeleton for assembling and disassembling the wheel leg actuators. The cutouts are located in non-load-bearing areas. The grid-shaped skeleton provides basic support, the reinforcing carbon plates improve overall strength, the cutouts in non-load-bearing areas reduce the overall vehicle weight, and the threaded interfaces enable quick assembly and disassembly of the wheel leg actuators. This allows the frame to adapt to complex field conditions and convenient maintenance needs while ensuring load-bearing capacity.
[0011] Preferably, to achieve 0° leg rotation, the hip joint axis includes a side plate fixedly connected to the grid-shaped frame, a pressure cap fixedly connected to the side plate away from the grid-shaped frame for axial compression and positioning, a main shaft rotatably connected to the side plate, a sleeve fixedly sleeved on the main shaft, and crossed roller bearings and a first cup bearing respectively disposed at both ends of the sleeve bearing to resist overturning torque and combined impact. The inner rings of the crossed roller bearings and the first cup bearing are fixedly connected to the outer side of the sleeve bearing, and the outer rings of the crossed roller bearings and the first cup bearing are fixedly connected to the pressure cap and the inner side of the thigh bar, respectively. Axial compression and positioning are achieved through the side plate and the pressure cap, torque is transmitted through the main shaft and the sleeve bearing, and the crossed roller bearings and the first cup bearing resist overturning torque and combined impact, so that the hip joint axis stably supports large-angle leg movement and protects the internal circuitry.
[0012] Preferably, in order to achieve flexible relative rotation of the upper and lower legs, the knee joint axis includes a second cup bearing disposed at one end of the sleeve shaft near the first cup bearing, and a pressure plate fixedly disposed on the side of the second cup bearing away from the first cup bearing. The inner ring of the second cup bearing is fixedly connected to the outer side of the sleeve shaft, and the outer ring of the second cup bearing is fixedly connected to the inner side of the lower leg bar. The second cup bearing supports the rotation of the lower leg bar, and the pressure plate completes axial compression and positioning, so that the knee joint axis meets the movement requirements of leg obstacle crossing and posture adjustment and simplifies the field maintenance process.
[0013] Preferably, to achieve synchronized leg movements and smooth obstacle crossing, the similar linkage assembly includes a first linkage hinged to the end of the thigh rod away from the hip joint axis and connected to the wheeled walking assembly; a second linkage hinged to the end of the first linkage near the thigh rod; a third linkage hinged to the end of the second linkage away from the first linkage; and a fourth linkage hinged to the end of the third linkage away from the second linkage. The end of the fourth linkage away from the third linkage is hinged to the end of the lower leg rod away from the knee joint axis. The two ends of the nitrogen spring are fixedly connected to the first linkage and the thigh rod, respectively. The knee joint axis, the first linkage, and the thigh rod are arranged in a triangular layout. The similar parallel transmission formed by the first linkage, the second linkage, the third linkage, and the fourth linkage, and the triangular layout of the knee joint axis, the first linkage, and the thigh rod improves structural rigidity, making leg movements coordinated and reducing the risk of rollover.
[0014] Preferably, to drive the hip and knee joints, the drive assembly includes a motor 1 and a motor 2 fixedly mounted on the side plate near the grid-shaped frame and located on both sides of the main shaft; a sprocket 1 and a sprocket 3 fixedly sleeved on the output shafts of motor 1 and motor 2 and located on both sides of the pressure cover; and a sprocket 2 and a sprocket 4 fixedly sleeved on the sleeve shaft. Sprocket 1 and sprocket 2, as well as sprocket 3 and sprocket 4, are all connected by a chain and transmit power. Motor 1 and motor 2 are both connected to the output end of the control system. Power is provided by motor 1 and motor 2, and sprocket 1, sprocket 2, sprocket 3, and sprocket 4, in conjunction with the chain, transmit torque, enabling the drive assembly to stably drive the legs to complete rotation, obstacle crossing, and self-rescue actions.
[0015] Preferably, to achieve chain tension, two wedge-shaped blocks are slidably connected to the side plate for respectively abutting against the first motor and the second motor. An adjusting bolt is screwed onto the side plate at the position corresponding to the wedge-shaped blocks. The adjusting bolt slides with the wedge-shaped blocks at a 45° angle, and the end of the adjusting bolt abuts against the wedge-shaped blocks. By sliding the wedge-shaped blocks to push the first motor and the second motor, the center distance between the sprockets is increased. The adjusting bolt pushes the wedge-shaped blocks to move at a 45° angle, so that the chain is kept taut and the stable operating cycle is extended.
[0016] Preferably, to achieve rolling motion, the wheeled travel assembly includes a hub disposed at one end of the connecting rod one away from the connecting rod two, an inner planetary carrier fixedly mounted on the side of the connecting rod one near the hub, an outer planetary carrier fixedly connected to the side of the inner planetary carrier away from the hub, a motor three fixedly mounted on the connecting rod one, a powder metallurgy gear one fixedly sleeved on the output shaft of the motor three and rotatably disposed between the inner and outer planetary carriers, a gear ring rotatably disposed between the inner and outer planetary carriers and located on the outer ring of the powder metallurgy gear one, and a cup bearing three disposed on the gear ring. Three powder metallurgical gears are rotatably connected between the inner and outer planetary carriers and distributed in a ring along the inner side of the gear ring. The two sides of each powder metallurgical gear mesh with the inner side of the gear ring and the outer side of the first powder metallurgical gear, respectively. The inner ring of the cup bearing is fixedly connected to the outer side of the gear ring, and the outer ring of the cup bearing is fixedly connected to the inner ring of the wheel hub. The third motor is connected to the output end of the control system. The third motor drives the first and second powder metallurgical gears to form a planetary reduction with the gear ring. The third cup bearing supports the wheel hub and absorbs impact, so that the wheel has sufficient power and stable operation in complex terrain.
[0017] Preferably, in order to protect the vehicle body and components, the wheeled following robot also includes a buffer energy absorption mechanism installed on the frame to absorb terrain impacts; by installing the buffer energy absorption mechanism on the frame, the elastic deformation and guiding buffering effect of the buffer energy absorption mechanism are used to offset the collision impact force generated by the robot under rough road, step and slope conditions, and avoid damage to internal sensors and electronic control components due to impact.
[0018] Preferably, in order to achieve impact absorption in complex terrain and protection of the vehicle body and components, the buffer energy absorption mechanism includes a first guide wheel hinged to the bottom of the grid-shaped frame and evenly distributed for guidance and buffering, an elastic carbon plate fixedly connected to both sides of the forward and backward ends of the grid-shaped frame, a mounting plate slidably connected to both sides of the elastic carbon plate, and a second guide wheel hinged to the mounting plate for buffering; the first guide wheel and the second guide wheel assist in guidance and buffering, the elastic carbon plate generates elastic deformation to absorb energy, and the mounting plate provides sliding support, so that the robot reduces the peak impact and protects the internal equipment under undulating and collision conditions.
[0019] This similar linkage-based wheeled-legged following robot achieves 0° omnidirectional leg rotation through the hip and knee joint axes. The similar linkage components ensure synchronized movement of the upper and lower legs, enabling the robot to roll at high speed on flat ground using the wheeled walking components without switching modes, and to continuously adjust the posture of the legs through the drive components in complex terrain. This achieves a seamless integration of wheeled and legged movements, solving the defects of poor walking continuity and interrupted following trajectory.
[0020] This wheel-legged following robot based on similar linkages utilizes the 360° rotation capability of the hip joint axis and the symmetrical linkage transmission of similar linkage components. This enables the robot to autonomously recover its posture after the posture perception module detects a fall. The control system drives multiple wheel-leg actuators to work together to generate a righting torque, thus solving the risk of being trapped and failing.
[0021] This wheel-legged following robot based on similar linkages connects the thigh leg to the similar linkage assembly via nitrogen springs. Utilizing the smooth elasticity of the springs, it achieves gravity compensation and energy storage. Combined with the instantaneous burst control of the drive assembly, the legs can perform active jumping movements, enabling it to cross ditches and large rocks that are wider than the leg length. It can meet the needs of long-term, high-intensity following operations in unstructured scenarios such as field inspection, emergency search and rescue, disaster exploration, and inspection of complex industrial plant areas.
[0022] This wheel-mounted following robot based on similar linkages uses nitrogen springs to provide a constant gravity-counteracting torque, reducing the static load on the drive components and extending its range.
[0023] This wheel-mounted following robot, based on similar linkages, absorbs vibrations through the damping characteristics of nitrogen springs and combines them with a buffer energy absorption mechanism. This achieves multi-layered energy absorption by exchanging stroke for buffering force, reducing the peak ground impact and protecting the internal structure. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of a wheel-legged following robot based on similar links;
[0025] Figure 2 This is a schematic diagram of the frame structure in a wheeled following robot based on similar linkages;
[0026] Figure 3 This is a schematic diagram of the wheel-leg actuator in a wheel-leg following robot based on similar linkages;
[0027] Figure 4 This is an exploded view of the wheel-leg actuator in a wheel-legged following robot based on similar linkages;
[0028] Figure 5 This is an exploded view of the hip joint axis system in a wheel-legged following robot based on similar linkages.
[0029] Figure 6 This is a partial structural diagram of the drive component in a wheel-legged following robot based on similar links;
[0030] Figure 7 This is an exploded structural diagram of a wheeled walking component in a similar linkage-based wheeled follower robot.
[0031] In the picture:
[0032] 1. Frame; 11. Grid-shaped frame; 12. Reinforced carbon fiber plate; 13. Hollowed-out design; 14. Threaded joint;
[0033] 2. Wheel-leg actuator; 21. Hip joint shaft system; 211. Side plate; 212. Pressure cap; 213. Main shaft; 214. Sleeve shaft; 215. Cross roller bearing; 216. Cup bearing assembly one; 22. Thigh rod; 23. Knee joint shaft system; 231. Pressure plate; 232. Cup bearing assembly two; 24. Lower leg rod; 25. Similar link assembly; 251. Linkage one; 252. Linkage two; 253. Linkage three; 254. Linkage four 26. Drive assembly; 261. Motor 1; 262. Sprocket 1; 263. Sprocket 2; 264. Motor 2; 265. Sprocket 3; 266. Sprocket 4; 27. Wheeled travel assembly; 271. Wheel hub; 272. Inner planetary carrier; 273. Outer planetary carrier; 274. Motor 3; 275. Powder metallurgy gear 1; 276. Powder metallurgy gear 2; 277. Gear ring; 278. Cup bearing 3; 28. Nitrogen spring;
[0034] 3. Wedge block;
[0035] 4. Buffer energy absorption mechanism; 41. Guide wheel one; 42. Elastic carbon plate; 43. Guide wheel two; 44. Mounting plate. Detailed Implementation
[0036] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0037] Example 1
[0038] This embodiment provides a wheel-footed following robot based on similar linkages, such as... Figures 1-7 As shown, the similar linkage-based wheeled following robot includes a frame 1 and wheel-leg actuators 2 respectively disposed on both sides of the frame 1. The wheel-leg actuators 2 include a hip joint axis 21 disposed on the frame 1 for 360° rotational support, a thigh rod 22 disposed on the hip joint axis 21, a knee joint axis 23 disposed on the hip joint axis 21 for relative rotation of the thigh and lower leg, a lower leg rod 24 disposed on the knee joint axis 23, a similar linkage assembly 25 hinged between the thigh rod 22 and the lower leg rod 24 for leg movement synchronization, and a similar linkage assembly 25 disposed on the frame 1 for driving the hip joint axis 21 and the knee joint axis 23 to rotate. The robot includes a moving drive assembly 26, a wheeled walking assembly 27 mounted on a similar link assembly 25 for rolling, and a nitrogen spring 28 mounted on the thigh rod 22 and the similar link assembly 25 for gravity compensation and attitude buffering. The wheeled following robot also includes a control system, a laser rangefinder fixed on the frame 1 for detecting the distance to obstacles in front, a magnetic sensor for detecting the orientation of the vehicle body, and an attitude perception module for measuring acceleration and angular velocity. The laser rangefinder, magnetic sensor, and attitude perception module are all connected to the input of the control system, and the drive assembly 26 and the wheeled walking assembly 27 are both connected to the output of the control system.
[0039] The frame 1 includes a grid-shaped frame 11, a reinforcing carbon plate 12 fixedly installed on the grid-shaped frame 11, a cutout 13 on the grid-shaped frame 11 and the reinforcing carbon plate 12, and threaded interfaces 14 on both sides of the grid-shaped frame 11 for disassembling and assembling the corresponding wheel leg actuators 2. The cutout 13 is located in the non-stress area.
[0040] In use, the frame 1 serves as the overall load-bearing foundation, with the grid-shaped skeleton 11 providing rigid support. Reinforcing carbon fiber plates 12 enhance structural rigidity and impact resistance. Hollowed-out areas 13 in non-load-bearing regions contribute to the overall lightweight design. Threaded interfaces 14 on both sides of the grid-shaped skeleton 11 provide standardized, quick-assembly / disassembly interfaces for the wheel-leg actuators 2, ensuring structural stability and facilitating field maintenance. Secondly, during robot movement, laser rangefinders continuously detect the distance to obstacles ahead, magnetic sensors continuously collect the vehicle's orientation signal, and the attitude perception module acquires real-time data on vehicle acceleration, angular velocity, and tilt posture. This information is synchronously transmitted to the control system, which then completes the system's... The system performs shape recognition, obstacle prediction, vehicle posture determination, and motion command calculation. Next, the control system outputs a power control signal to the drive assembly 26. The drive assembly 26 drives the hip joint axis 21 and knee joint axis 23. The hip joint axis 21 provides 360° omnidirectional rotational support for the leg, while the knee joint axis 23 drives the thigh bar 22 and lower leg bar 24 to achieve flexible relative rotation, providing basic motion conditions for leg posture adjustment, obstacle crossing, and self-rescue. Subsequently, the similar linkage assembly 25, hinged between the thigh bar 22 and lower leg bar 24, maintains synchronous linkage with the leg movement, ensuring coordinated and interference-free movement between the thigh bar 22, lower leg bar 24, and wheeled walking assembly 27, maintaining consistent leg movement. The system ensures stability of the robot's posture and body. Simultaneously, the nitrogen spring 28 connects the thigh rod 22 and the similar linkage assembly 25, providing a stable gravity compensation torque with a gentle elastic force. This reduces the static load on the drive assembly 26, suppresses leg posture tremors, and stores elastic potential energy when the legs are charging. When the robot is traveling on flat ground, the control system drives the wheeled walking assembly 27 to roll at high speed, maintaining efficient and continuous passage. When the robot encounters obstacles such as ditches, rocks, or steps, the control system, based on sensor data, controls the drive assembly 26 to lift and extend the legs, coordinating with the nitrogen spring 28 to store energy, which is then released instantaneously. Utilizing the linkage characteristics of the similar linkage assembly 25 and the leg structure, the system actively... The robot can jump or crash into obstacles to achieve efficient crossing of wide obstacles. In addition, when the robot rolls over or falls over due to complex terrain, the posture perception module immediately feeds back the abnormal posture signal to the control system. The control system quickly drives the symmetrical linkage of the two wheel-leg actuators 2 to exert force. With the help of the 360° rotation capability of the hip joint axis system 21 and the synchronous transmission characteristics of the similar linkage assembly 25, a righting torque is generated, which autonomously restores the robot body to the normal driving posture, avoiding being trapped and failing. Ultimately, the robot can achieve high-speed movement, continuous obstacle crossing, autonomous escape, and long-term high-intensity stable following operation in unstructured scenarios such as field inspection, emergency search and rescue, disaster exploration, and inspection of complex industrial plant areas.
[0041] Specifically, the hip joint axis system 21 includes a side plate 211 fixedly connected to the grid-shaped frame 11, a pressure cap 212 fixedly connected to the side plate 211 away from the grid-shaped frame 11 for axial clamping and positioning, a main shaft 213 rotatably connected to the side plate 211, a sleeve shaft 214 fixedly sleeved on the main shaft 213, and crossed roller bearings 215 and cup bearings 216 respectively disposed at both ends of the sleeve shaft 214 to resist overturning moment and combined impact. The inner rings of the crossed roller bearings 215 and cup bearings 216 are fixedly connected to the outer side of the sleeve shaft 214, and the outer rings of the crossed roller bearings 215 and cup bearings 216 are fixedly connected to the pressure cap 212 and the inner side of the thigh rod 22 respectively.
[0042] It should be added that the end of the spindle 213 away from the side plate 211 is connected to the wire through a slip ring. The spindle 213 is provided with an armor plate for covering the outside of the slip ring to protect the slip ring and eliminate the risk of pulling and entanglement of the wire due to the rotation of the legs. The armor plate is fixedly connected to the side plate 211.
[0043] When the hip joint shaft system 21 is in operation, the side plate 211, fixed to the grid-shaped frame 11, first serves as the overall mounting base, providing stable support and mounting positioning for the internal rotating components. Next, the pressure cap 212 is fixed to the outside of the side plate 211, achieving axial clamping and positioning of the internal bearings and shaft, preventing axial movement of the components and ensuring assembly accuracy. Then, the main shaft 213 is rotatably supported on the side plate 211, serving as the core rotating carrier of the hip joint shaft system 21. The sleeve shaft 214 is fixedly sleeved on the main shaft 213, rotating synchronously with the main shaft 213 and used to support the bearings and transmit rotational power. Then, crossed roller bearings 215 and cup bearings 216 are respectively mounted at both ends of the sleeve shaft 214, wherein the inner ring of the crossed roller bearing 215 and the inner ring of the cup bearing 216 are... The outer side of the sleeve shaft 214 is fixedly connected, and the outer ring is fixedly connected to the pressure cap 212. It is used to bear radial loads and overturning moments. The inner ring of the cup bearing 216 is fixedly connected to the outer side of the sleeve shaft 214, and the outer ring is fixedly connected to the inner side of the thigh rod 22. It is used to bear compound impact loads and ensure smooth rotation. When the drive assembly 26 drives the sleeve shaft 214 to rotate, the sleeve shaft 214, through the coordinated support of the crossed roller bearing 215 and the cup bearing 216, drives the thigh rod 22 to achieve 360° omnidirectional stable rotation. At the same time, it resists the overturning moment and multi-directional compound impacts brought by complex terrain, ensuring that the hip joint axis system 21 can operate reliably under conditions such as obstacle crossing, turning over, and high-speed driving, providing stable, high-strength, and high-degree-of-freedom rotational support for leg movement.
[0044] Furthermore, the knee joint axis 23 includes a second bowl bearing 232 disposed at one end of the sleeve shaft 214 near the first bowl bearing 216, and a pressure plate 231 fixedly disposed on the side of the second bowl bearing 232 away from the first bowl bearing 216. The inner ring of the second bowl bearing 232 is fixedly connected to the outer side of the sleeve shaft 214, and the outer ring of the second bowl bearing 232 is fixedly connected to the inner side of the lower leg rod 24.
[0045] When the knee joint axis 23 is working, firstly, using the end of the sleeve shaft 214 near the first cup bearing 216 as the installation reference, the second cup bearing 232 is assembled into place, so that the inner ring of the second cup bearing 232 is fixedly connected to the outer side of the sleeve shaft 214, forming an inner support structure that rotates synchronously with the sleeve shaft 214. Secondly, the pressure plate 231 is fixed on the side of the second cup bearing 232 away from the first cup bearing 216, and the second cup bearing 232 is axially pressed and positioned to ensure that the bearing is firmly installed and the rotation accuracy is stable. Then, the outer ring of the second cup bearing 232 is fixedly connected to the inner side of the lower leg rod 24, so that the lower leg rod 24 relies on the cup bearing. The second 232 allows free rotation relative to the sleeve shaft 214. When the drive assembly 26 drives the sleeve shaft 214 to move, the sleeve shaft 214 drives the inner ring of the second 232 of the cup bearing to rotate synchronously. The outer ring of the second 232 of the cup bearing drives the lower leg bar 24 to rotate flexibly relative to the thigh bar 22. Together with the 360° rotation support of the hip joint axis system 21, it completes the leg posture adjustment, obstacle crossing extension, contraction and reset, and fall self-rescue actions. At the same time, it relies on the load-bearing characteristics of the second 232 of the cup bearing to resist the impact load brought by complex terrain, ensuring smooth rotation of the knee joint axis system 23 and meeting the usage requirements of stable movement and maintenance in field conditions.
[0046] Furthermore, the similar linkage assembly 25 includes a first linkage 251 hinged to the end of the thigh rod 22 away from the hip joint axis 21 and connected to the wheeled walking assembly 27, a second linkage 252 hinged to the end of the first linkage 251 near the thigh rod 22, a third linkage 253 hinged to the end of the second linkage 252 away from the first linkage 251, and a fourth linkage 254 hinged to the end of the third linkage 253 away from the second linkage 252. The end of the fourth linkage 254 away from the third linkage 253 is hinged to the end of the lower leg rod 24 away from the knee joint axis 23. The two ends of the nitrogen spring 28 are fixedly connected to the first linkage 251 and the thigh rod 22 respectively. The knee joint axis 23, the first linkage 251 and the thigh rod 22 are arranged in a triangular layout.
[0047] When the hip joint axis 21 and knee joint axis 23 drive the thigh rod 22 and lower leg rod 24 to rotate and change posture, the lower leg rod 24 first drives the fourth link 254 to hinge and swing, and then the fourth link 254 drives the third link 253 and the second link 252 to deflect synchronously, finally transmitting the motion torque to the first link 251, so that the entire set of similar link components 25 follows the posture of the thigh and lower leg to swing synchronously, always maintaining a consistent motion trajectory without deviation or motion interference. When the robot encounters obstacles such as steps or ditches, the knee joint axis 23 drives the lower leg rod 24 to lift and bend upward, and the lower leg rod 24 pulls the fourth link 254 to fold inward, which in turn drives the third link 253 and the second link 252 to close the angle synchronously. The first link 251 adjusts the angle adaptively with the posture, and at the same time, the nitrogen spring 28 is compressed to store elastic potential energy, waiting for the wheel walking component 2 to... 7. After crossing the top of the obstacle, the nitrogen spring 28 releases its stored energy to push the first link 251 to reset, causing each link to extend and return to its original position in sequence, smoothly completing the obstacle crossing action. When the robot rolls over or falls over in complex terrain, the attitude perception module feeds back a signal to the control system, driving the two wheel leg actuators 2 to move synchronously. The thigh rods 22 and the lower leg rods 24 on both sides extend in opposite directions, causing their respective links 1 251, 252, 3 253, and 4 254 to swing symmetrically and synchronously. Relying on the linkage transmission characteristics of similar link components 25, a balanced righting torque is formed. With the buffering and unloading effect of the nitrogen spring 28, the tilted body support is slowly lifted and returned to the right position, realizing autonomous attitude reset. Throughout the process, the synchronous cooperation of multiple links ensures the coordination of the action and the balance of force, meeting the requirements for obstacle crossing, self-rescue after falling over, and long-term stable following operation.
[0048] Furthermore, the drive assembly 26 includes a motor 261 and a motor 264 fixedly mounted on the side plate 211 near the grid frame 11 and located on both sides of the main shaft 213, a sprocket 262 and a sprocket 265 fixedly sleeved on the output shafts of the motors 261 and 264 and located on both sides of the pressure cover 212, and a sprocket 263 and a sprocket 266 fixedly sleeved on the sleeve shaft 214. The sprockets 262 and 263, as well as the sprockets 265 and 266, are all connected by a chain and transmit power. The motors 261 and 264 are both connected to the output end of the control system.
[0049] Under normal driving conditions, the control system synchronously operates the control motors 261 and 264 on both sides of the grid-shaped frame 11. Motor 261 drives sprocket 262 to rotate and transmits the rotation via chain to sprocket 263. Motor 264 drives sprocket 265 to rotate and transmits the rotation via chain to sprocket 266. The two sets of sprockets synchronously drive the sleeve shaft 214 to rotate at a uniform speed, thereby driving the hip joint axis system 21 to rotate smoothly. This, in conjunction with the similar linkage assembly 25, maintains the leg's regular posture and ensures the smooth movement of the wheeled walking assembly 27. When obstacles such as steps or ditches are detected in front of the robot, the control system adjusts the output speed and direction of motors 261 and 264. Through the chain transmission of sprockets 262, 263, 265, and 266, the sleeve shaft 214 is driven to rotate the hip joint axis system 21 at a large angle, thereby lifting and adjusting the angle of the thigh rod 22. Furthermore, the internal links 25 of the similar linkage assembly 25 are sequentially hinged, swing, and folded to adjust the overall span and ground clearance of the wheel legs, completing the posture adjustment and stepping obstacle crossing action. When the robot rolls over or tilts in complex terrain, the control system receives the posture signal from the posture perception module and precisely controls the symmetrical and opposite output power of motors 261 and 264 of the drive assembly 26 on both sides of the grid frame 11. Through their respective corresponding sprocket and chain transmission pairs, the two sleeve shafts 214 on both sides rotate in the same direction, causing the two thigh rods 22 on both sides to extend outward symmetrically, driving each link in the similar linkage assembly 25 on both sides to swing synchronously to form a symmetrical support torque. Relying on the mechanical characteristics of the coordinated transmission of multiple sets of links, the robot body is gradually lifted up, and the overall linkage with the wheel leg actuator 2 completes the autonomous uprighting and resetting.
[0050] In addition, two wedge-shaped blocks 3 are slidably connected on the side plate 211 for respectively abutting against motor 1 261 and motor 2 264. An adjusting bolt is screwed on the side plate 211 at the position corresponding to the wedge-shaped blocks 3. The adjusting bolt slides with the wedge-shaped blocks 3 at a 45° angle, and the end of the adjusting bolt abuts against the wedge-shaped blocks 3.
[0051] When the operation begins or the chain becomes loose, the adjusting bolt is rotated to push it along its own axis toward the wedge block 3. The end of the adjusting bolt presses against the inclined surface of the wedge block 3. Since the two are engaged at a 45° angle, the axial thrust of the adjusting bolt is converted into a horizontal sliding thrust of the wedge block 3 along the side plate 211. The thrust is decomposed into a lateral component along the sliding direction of the side plate 211, pushing the wedge block 3 to slide smoothly along the side plate 211. Subsequently, the sliding wedge block 3 will synchronously push the corresponding motor 1 261 or motor 2 264, causing motor 1 261 or motor 2 264 to move in the guide direction, thereby increasing the contact between the sprocket 1 262 on the motor output shaft and the sleeve shaft 214. The center distance between sprocket 263, sprocket 265 on the output shaft of motor 264 and sprocket 266 on sleeve shaft 214 is adjusted. After the chain reaches the appropriate tension, the adjusting bolt is stopped. The wedge block 3 remains in a fixed position under the continuous abutment of the adjusting bolt, thereby fixing the position of the motor and ensuring that the chain is always in a taut state. This prevents the chain from slipping or falling off when the drive assembly 26 is working, ensuring smooth and stable power transmission between sprocket 262, sprocket 263, sprocket 265, sprocket 266 and the chain. It also facilitates quick adjustment when the chain becomes loose, adapting to the power transmission needs of the robot under complex working conditions for a long time.
[0052] It is worth noting that the wheeled walking assembly 27 includes a hub 271 located at the end of the first connecting rod 251 away from the second connecting rod 252, an inner planetary carrier 272 fixedly mounted on the side of the first connecting rod 251 near the hub 271, an outer planetary carrier 273 fixedly connected to the side of the inner planetary carrier 272 away from the hub 271, a motor 274 fixedly mounted on the first connecting rod 251, a powder metallurgy gear 275 fixedly sleeved on the output shaft of the motor 274 and rotatably disposed between the inner planetary carrier 272 and the outer planetary carrier 273, and a rotatably disposed between the inner planetary carrier 272 and the outer planetary carrier 273. The system includes a gear ring 277 located between and on the outer ring of powder metallurgy gear 275, a cup bearing 278 mounted on the gear ring 277, and three powder metallurgy gears 276 rotatably connected between the inner planetary carrier 272 and the outer planetary carrier 273 and distributed in a ring along the inner side of the gear ring 277. The two sides of the powder metallurgy gears 276 mesh with the inner side of the gear ring 277 and the outer side of the powder metallurgy gear 275, respectively. The inner ring of the cup bearing 278 is fixedly connected to the outer side of the gear ring 277, and the outer ring of the cup bearing 278 is fixedly connected to the inner ring of the hub 271. The motor 274 is connected to the output end of the control system.
[0053] When the control system sends a control command to motor 3 274, motor 3 274 starts, driving the powder metallurgy gear 1 275, which is fixedly sleeved on its output shaft, to rotate. Powder metallurgy gear 1 275 serves as the power input end. Since three powder metallurgy gears 276 are rotatably connected between the inner planetary carrier 272 and the outer planetary carrier 273, and all mesh with powder metallurgy gear 1 275 and simultaneously mesh with the inner side of the gear ring 277, the high-speed rotation output by motor 3 274 is transmitted to powder metallurgy gears 276 via powder metallurgy gear 1 275. Powder metallurgy gears 276 rotate around powder metallurgy gear 1 275. Simultaneously, the gear ring 277 rotates synchronously. Through the planetary transmission method of multi-gear meshing, the high-speed, low-torque rotation of motor 274 is converted into low-speed, high-torque rotation, completing the power reduction and torque increase, meeting the power requirements when the robot walks smoothly. Since the cup bearing 278 is installed on the gear ring 277, its outer ring is fixedly connected to the hub 271, and its inner ring is fixedly connected to the gear ring 277. This can effectively reduce the frictional resistance between the gear ring 277 and the hub 271, avoid problems such as jamming and wear during rotation, ensure smooth power transmission, and thus drive the hub 271 to rotate smoothly, realizing the robot's rolling movement.
[0054] Example 2
[0055] Unlike Example 1, as Figures 1-2 As shown, in order to absorb the impact of complex terrain and protect the vehicle body and components, the wheel-legged following robot also includes a buffer energy absorption mechanism 4 set on the frame 1 for absorbing terrain impact; the buffer energy absorption mechanism 4 includes a guide wheel 41 hinged to the bottom of the grid-shaped frame 11 and evenly distributed for guidance and buffering, an elastic carbon plate 42 fixedly connected to both sides of the forward end and the backward end of the grid-shaped frame 11, a mounting plate 44 slidably connected to both sides of the elastic carbon plate 42, and a guide wheel 43 hinged to the mounting plate 44 for buffering.
[0056] When the robot follows the wheels on rough roads, steps, ditches, and other complex terrains, the impact force generated by the ground is first absorbed by the guide wheels 41 and 43 in synchronous contact. The guide wheels 41 and 43 dissipate local hard collisions through their own rotation, while transferring the vertical impact load to the elastic carbon plate 42. After being loaded, the elastic carbon plate 42 undergoes elastic bending deformation, absorbing and dissipating the terrain impact energy by relying on its own elastic properties. The mounting plate 44 slides slightly on the elastic carbon plate 42 according to the force position, making minor adjustments to offset the assembly gap and terrain angle deviation, and avoiding stress concentration. After the robot leaves the uneven road surface, the elastic carbon plate 42 elastically resets itself, driving the mounting plate 44 and guide wheels 43 back to their initial positions, always maintaining the bottom buffer protection state. Throughout the process, the contact guidance of guide wheels 41 and 43, combined with the deformation energy absorption of the elastic carbon plate 42, effectively attenuates the bumps and impacts brought by complex terrain, protects the frame 1 and internal electronic control and sensing components from vibration damage, and improves the overall driving stability of the robot and its adaptability to complex field conditions.
[0057] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and concept of this application, should be included within the scope of protection of this application.
Claims
1. A wheel-legged following robot based on similar linkage, comprising a frame (1) and wheel-leg actuators (2) respectively disposed on both sides of the frame (1); Its features are: The wheel-leg actuator (2) includes a hip joint shaft (21) mounted on the frame (1) for 360° rotational support, a thigh rod (22) mounted on the hip joint shaft (21), a knee joint shaft (23) mounted on the hip joint shaft (21) for relative rotation of the thigh and lower leg, a lower leg rod (24) mounted on the knee joint shaft (23), a similar linkage assembly (25) hinged between the thigh rod (22) and the lower leg rod (24) for leg movement synchronization, a drive assembly (26) mounted on the frame (1) for driving the hip joint shaft (21) and the knee joint shaft (23) to rotate, a wheeled walking assembly (27) mounted on the similar linkage assembly (25) for rolling, and a nitrogen spring (28) mounted on the thigh rod (22) and the similar linkage assembly (25) for gravity compensation and posture buffering. The wheeled following robot also includes a control system, a laser rangefinder fixed on the frame (1) for detecting the distance to obstacles in front, a magnetic sensor for detecting the orientation of the vehicle body, and an attitude perception module for measuring acceleration and angular velocity. The laser rangefinder, magnetic sensor and attitude perception module are all connected to the input end of the control system, and the drive assembly (26) and wheeled walking assembly (27) are both connected to the output end of the control system.
2. The wheel-legged following robot based on similar linkages according to claim 1, characterized in that: The frame (1) includes a grid-shaped frame (11), a reinforcing carbon plate (12) fixedly installed on the grid-shaped frame (11), a cutout (13) on the grid-shaped frame (11) and the reinforcing carbon plate (12), and threaded interfaces (14) on both sides of the grid-shaped frame (11) for disassembly and assembly of the wheel leg actuator (2). The cutout (13) is located in a non-stressed area.
3. The wheel-legged following robot based on similar linkages according to claim 2, characterized in that: The hip joint axis (21) includes a side plate (211) fixedly connected to the grid-shaped frame (11), a pressure cap (212) fixedly connected to the side plate (211) away from the grid-shaped frame (11) for axial clamping and positioning, a main shaft (213) rotatably connected to the side plate (211), a sleeve shaft (214) fixedly sleeved on the main shaft (213), and cross roller bearings (215) and cup bearings (216) respectively provided at both ends of the sleeve shaft (214) for resisting overturning moment and combined impact. The inner rings of the cross roller bearings (215) and cup bearings (216) are fixedly connected to the outside of the sleeve shaft (214), and the outer rings of the cross roller bearings (215) and cup bearings (216) are fixedly connected to the pressure cap (212) and the inside of the thigh bar (22) respectively.
4. The wheel-legged following robot based on similar linkages according to claim 3, characterized in that: The knee joint axis (23) includes a second bowl bearing (232) disposed on the end of the sleeve shaft (214) near the first bowl bearing (216) and a pressure plate (231) fixedly disposed on the side of the second bowl bearing (232) away from the first bowl bearing (216). The inner ring of the second bowl bearing (232) is fixedly connected to the outer side of the sleeve shaft (214), and the outer ring of the second bowl bearing (232) is fixedly connected to the inner side of the lower leg rod (24).
5. The wheel-legged following robot based on similar linkages according to claim 4, characterized in that: The similar linkage assembly (25) includes a first linkage (251) hinged to the end of the thigh rod (22) away from the hip joint axis (21) and connected to the wheeled walking assembly (27); a second linkage (252) hinged to the end of the first linkage (251) near the thigh rod (22); a third linkage (253) hinged to the end of the second linkage (252) away from the first linkage (251); and a fourth linkage (253) hinged to the end of the third linkage (253). Link 4 (254) is located away from one end of link 2 (252). The end of link 4 (254) away from link 3 (253) is hinged to the end of the lower leg rod (24) away from the knee joint axis (23). The two ends of the nitrogen spring (28) are fixedly connected to link 1 (251) and thigh rod (22) respectively. The knee joint axis (23), link 1 (251) and thigh rod (22) are arranged in a triangular layout.
6. The wheel-legged following robot based on similar linkages according to claim 3, characterized in that: The drive assembly (26) includes a motor 1 (261) and a motor 2 (264) fixedly installed on the side plate (211) near the grid frame (11) and located on both sides of the main shaft (213), a sprocket 1 (262) and a sprocket 3 (265) fixedly sleeved on the output shafts of the motor 1 (261) and the motor 2 (264) and located on both sides of the pressure cover (212), and a sprocket 2 (263) and a sprocket 4 (266) fixedly sleeved on the sleeve shaft (214). The sprocket 1 (262) and the sprocket 2 (263), as well as the sprocket 3 (265) and the sprocket 4 (266), are all connected by a chain and transmit power. The motor 1 (261) and the motor 2 (264) are both connected to the output end of the control system.
7. The wheel-legged following robot based on similar linkages according to claim 6, characterized in that: The side plate (211) is slidably connected to two wedge blocks (3) for respectively abutting against the first motor (261) and the second motor (264). An adjusting bolt is screwed onto the side plate (211) at the position corresponding to the wedge block (3). The adjusting bolt slides with the wedge block (3) at a 45° angle, and the end of the adjusting bolt abuts against the wedge block (3).
8. The wheel-legged following robot based on similar linkages according to claim 5, characterized in that: The wheeled walking assembly (27) includes a hub (271) disposed at one end of the connecting rod one (251) away from the connecting rod two (252), an inner planetary carrier (272) fixedly mounted on the side of the connecting rod one (251) near the hub (271), an outer planetary carrier (273) fixedly connected to the side of the inner planetary carrier (272) away from the hub (271), a motor three (274) fixedly mounted on the connecting rod one (251), a powder metallurgy gear one (275) fixedly sleeved on the output shaft of the motor three (274) and rotatably disposed between the inner planetary carrier (272) and the outer planetary carrier (273), and a rotatably disposed between the inner planetary carrier (272) and the outer planetary carrier (273). The gear ring (277) on the outer ring of the powder metallurgy gear one (275), the cup bearing three (278) on the gear ring (277), and the three powder metallurgy gear two (276) rotatably connected between the inner planetary carrier (272) and the outer planetary carrier (273) and distributed in a ring along the inner side of the gear ring (277). The two sides of the powder metallurgy gear two (276) mesh with the inner side of the gear ring (277) and the outer side of the powder metallurgy gear one (275) respectively. The inner ring of the cup bearing three (278) is fixedly connected to the outer side of the gear ring (277). The outer ring of the cup bearing three (278) is fixedly connected to the inner ring of the hub (271). The motor three (274) is connected to the output end of the control system.
9. The wheel-legged following robot based on similar linkages according to claim 2, characterized in that: The wheeled following robot also includes a buffer energy-absorbing mechanism (4) mounted on the frame (1) for absorbing terrain impacts.
10. The wheel-legged following robot based on similar linkages according to claim 9, characterized in that: The buffer energy absorption mechanism (4) includes a guide wheel (41) hinged to the bottom of the grid frame (11) and evenly distributed for guidance and buffering, an elastic carbon plate (42) fixedly connected to both sides of the forward end and the backward end of the grid frame (11), a mounting plate (44) slidably connected to both sides of the elastic carbon plate (42), and a guide wheel (43) hinged to the mounting plate (44) for buffering.