1. An automatic jack jacking disaster relief system based on a foot robot is characterized by comprising a multi-foot robot (1) and a control terminal,

a jack (2), a sensor, a communication component and an IMU inertia measurement unit are arranged on the multi-legged robot (1),

the communication assembly is in communication connection with the control terminal, so that the control terminal can control the motion of the multi-legged robot (1);

the sensor is used for identifying terrain and transmitting terrain information to the control terminal through the communication assembly;

the IMU inertia measurement unit is used for obtaining the attitude, speed and displacement information of the robot and assisting the robot to keep stable standing and walking.

2. An automatic jack jacking disaster relief system based on a foot type robot is characterized in that,

the sensor comprises a laser radar, and a three-dimensional map is established by scanning the surrounding environment of the robot through the laser radar.

3. An automatic jack jacking disaster relief system based on a foot type robot is characterized in that,

the robot is a multi-legged robot,

the multi-legged robot (1) comprises a rack (12) and legs (11) connected to the rack (12), wherein the legs (11) comprise thigh parts (111), shank parts (112) and pull rods (113), a thigh steering gear (114) is arranged at the upper end of the thigh part (111), the thigh steering gear (114) is fixed on the rack (12),

the frame (12) comprises a base plate (123), and the base plate (123) is used for bearing the jack (2).

4. An automatic jacking disaster relief method based on a multi-legged robot is characterized in that,

the method comprises the following steps:

s1, detecting the environment and establishing a three-dimensional map;

s2, moving the robot to a position to be jacked;

and S3, lifting up the heavy object for rescue.

5. The automatic jacking disaster relief method based on the multi-legged robot as claimed in claim 4,

in step S2, the operator determines the terrain from the three-dimensional map, and manipulates the robot to move to a target position where the operator needs to lift the vehicle,

at least three feet of the multi-legged robot land on the ground in the walking process to support the robot,

the walking stability control is realized by setting the center of gravity in a stable region;

the stable region is a triangular region formed on three legs of the ground.

6. The automatic jacking disaster relief method based on the multi-legged robot as claimed in claim 5,

in the walking stability control, the gravity center is limited in a safe and stable area,

the safe stable area refers to an area after the fixed range of the edge of the stable area is removed.

7. The automatic jacking disaster relief method based on the multi-legged robot as claimed in claim 5,

during walking, with a stability margin S_mThe track is a gravity center track, the track of the robot is controlled,

the stability margin S_mExpressed as:

S_m＝min(S_m1,S_m2,S_m3) (seven)

Wherein S is_m1,S_m2,S_m3Respectively center of gravity to safety and stabilityThe distance of three sides of the region.

8. The automatic jacking disaster relief method based on the multi-legged robot as claimed in claim 5,

in the walking process, selecting a stability margin S_mAnd a connecting line of the front and back moving midpoints of the tracks is a gravity center moving control track.

9. The automatic jacking disaster relief method based on the multi-legged robot as claimed in claim 4,

the robot carries out walking stability control in the moving process, and the walking stability control comprises the following substeps:

s211, obtaining the angle of each joint of the walking foot of the robot;

and S212, compensating the rotation angle of each joint.

10. The automatic jacking disaster relief method based on the multi-legged robot according to claim 9,

in step S212, the navigation angle of the substrate with respect to the horizontal plane is measured by the IMU inertial unit, and the angles of the joints of the robot are adjusted using the real-time state of the substrate so that the substrate is in a stable state.

Background

In disaster relief, for example, in earthquake disaster relief, it is often necessary to jack up a heavy object to relieve people being pressed and trapped, or to open a passageway.

However, in the rescue process, the situation that a heavy object needs to be lifted in a narrow space where rescuers cannot enter often occurs, and in the situation, the rescuers often need to clean peripheral sundries first and rescue after the space is enlarged, so that the rescue time is delayed seriously, and the injury of rescued people is aggravated.

Therefore, there is a need to develop a system capable of walking in a narrow space and lifting a heavy object at a designated position, so as to improve rescue speed, reduce the risk factor of people suffering from a disaster, and protect the safety of rescuers.

Disclosure of Invention

In order to overcome the problems, the inventor of the present invention has conducted intensive research to design an automatic jack jacking disaster relief system based on a legged robot.

The foot type robot is used as a bionic robot, has low requirement on the flatness of a walking road condition, can cross obstacles, travels on a rugged and complicated road surface, and has great advantages in the aspect of crossing terrain obstacles.

The jack is light and small lifting equipment which takes a rigid jacking piece as a working device and jacks a heavy object through a top bracket or a bottom supporting claw within a small stroke. The structure is light, firm and reliable, and can be widely applied to lifting, supporting and other works. The traditional jack is generally applied to departments of factories, mines, transportation and the like as vehicle repair and other lifting, supporting and other works, generally speaking, a new application scene is lacked, and the novelty of the application occasion is greatly limited.

At present, in the aspect of greatly improving the load and adaptability of the foot type bionic robot, the application of a jack device is still blank, systematic research and design are not available, and the simple and flexible characteristics of the hydraulic jack can be just combined with the foot type robot, so that the load bearing capacity of the latter is greatly improved.

The jack automatic jacking disaster relief system based on the foot type robot comprises a multi-foot robot 1 and a control terminal,

the multi-legged robot 1 is provided with a jack 2, a sensor, a communication component and an IMU inertia measurement unit,

the communication component is in communication connection with the control terminal, so that the control terminal can control the motion of the multi-legged robot 1;

the sensor is used for identifying terrain and transmitting terrain information to the control terminal through the communication assembly;

the IMU inertia measurement unit is used for obtaining the attitude, speed and displacement information of the robot and assisting the robot to keep stable standing and walking.

Preferably, the sensor comprises a laser radar, and the three-dimensional map is built by scanning the surrounding environment of the robot through the laser radar.

Preferably, the robot is a multi-legged robot,

the multi-legged robot 1 comprises a frame 12 and legs 11 connected to the frame 12, wherein the legs 11 comprise thigh parts 111, shank parts 112 and pull rods 113, the upper end of the thigh part 111 is provided with a thigh steering gear 114, the thigh steering gear 114 is fixed on the frame 12,

the frame 12 comprises a base plate 123, the base plate 123 being adapted to receive the jack 2.

On the other hand, the invention also provides an automatic jacking disaster relief method based on the multi-legged robot, which comprises the following steps:

s1, detecting the environment and establishing a three-dimensional map;

s2, moving the robot to a position to be jacked;

and S3, lifting up the heavy object for rescue.

In a preferred embodiment, in step S2, the operator determines the terrain from the three-dimensional map, and the operator moves the robot to a target position where the operator needs to lift the vehicle,

at least three feet of the multi-legged robot land on the ground in the walking process to support the robot,

the walking stability control is realized by setting the center of gravity in a stable region;

the stable region is a triangular region formed on three legs of the ground.

In a preferred embodiment, in the walking stability control, the center of gravity is defined in a safe stable region,

the safe stable area refers to an area after the fixed range of the edge of the stable area is removed.

In a preferred embodiment, the margin of stability S is used during walking_mThe track is a gravity center track, the track of the robot is controlled,

the stability margin S_mExpressed as:

S_m＝min(S_m1,S_m2,S_m3) (seven)

Wherein S is_m1,S_m2,S_m3The distances from the center of gravity to three sides of the safety and stability area are respectively.

In a preferred embodiment, the stability margin S is selected during walking_mAnd a connecting line of the front and back moving midpoints of the tracks is a gravity center moving control track.

In a preferred embodiment, the robot performs walking stabilization control during the movement, and the walking stabilization control includes the following sub-steps:

s211, obtaining the angle of each joint of the walking foot of the robot;

and S212, compensating the rotation angle of each joint.

In a preferred embodiment, in step S212, the navigation angle of the substrate with respect to the horizontal plane is measured by the IMU inertial unit, and the angles of the joints of the robot are adjusted using the real-time state of the substrate so that the substrate is in a steady state.

The invention has the advantages that:

(1) the foot type robot is combined with the jack, so that the problems of insufficient load capacity and insufficient structural strength of the traditional foot type robot are solved. The whole system has good terrain adaptability and tonnage at the same time;

(2) overcomes the defect that the traditional manual jack is limited by space and manual control

(3) The lifting device is applied to earthquake relief, can enter a narrow space where rescue workers cannot enter, and lifts a heavy object at a specified position;

(4) the rescue robot can replace people to enter a dangerous area to carry out rescue, protect the safety of rescuers, guarantee the safety of people suffering from disasters, reduce the labor cost and accelerate the rescue speed and efficiency.

Drawings

Fig. 1 is a schematic diagram illustrating the overall structure of an automatic jacking disaster relief system based on a multi-legged robot according to a preferred embodiment of the invention;

fig. 2 shows a schematic structural view of a leg of the automatic jacking disaster relief system based on the multi-legged robot according to a preferred embodiment of the invention;

fig. 3 shows a four-legged robot structure diagram of the automatic lifting and disaster relief system based on the multi-legged robot according to a preferred embodiment of the present invention;

fig. 4 shows a schematic structural view of a jack and a frame of an automatic jacking disaster relief system based on a multi-legged robot according to a preferred embodiment of the present invention;

fig. 5 shows a schematic structural view of a jack of the automatic jacking disaster relief system based on the multi-legged robot according to a preferred embodiment of the present invention;

fig. 6 shows a schematic structural view of a jack of the automatic jacking disaster relief system based on the multi-legged robot according to a preferred embodiment of the present invention;

fig. 7 is a schematic view showing the positional relationship of coordinate systems when a robot base plate of the multi-legged robot-based automatic lifting disaster relief system rotates according to a preferred embodiment of the present invention;

fig. 8 is a schematic view illustrating a safety and stability area in an automatic multi-legged robot-based jacking disaster relief method according to a preferred embodiment of the present invention;

fig. 9 shows a stability margin S in the multi-legged robot-based automatic jacking disaster relief method according to a preferred embodiment of the present invention_mA schematic diagram;

fig. 10 is a schematic diagram illustrating a center of gravity movement control trajectory in the multi-legged robot-based automatic jacking disaster relief method according to a preferred embodiment of the present invention;

fig. 11 shows a simplified diagram of the positions of the robot foot joints of the multi-legged robot-based automatic lifting disaster relief system according to a preferred embodiment of the present invention.

Reference numerals

1-a quadruped robot;

2-a jack;

11-a stand;

12-a frame;

21-thin plate;

22-jack steering engine;

23-a double rocker structure assembly;

24-a hydraulic piston rod;

25-an oil valve;

26-landing steering engines;

111-thigh section;

112-lower leg portion;

113-a pull rod;

114-thigh steering engine;

115-pull rod steering engine;

116-fuselage thigh link;

117-sole of the foot;

121-a frame tube;

122-end plate;

123-a substrate;

124-leg outward swing steering engines;

125-bolt;

231-a rocker;

232-connecting rod;

233-power press rod;

234-strengthen rocker;

1111-a substrate;

1112-reinforcing ribs;

1151-rudder bar.

Detailed Description

The invention is explained in more detail below with reference to the figures and examples. The features and advantages of the present invention will become more apparent from the description.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

On one hand, the invention provides an automatic jacking disaster relief system based on a multi-legged robot, which comprises the multi-legged robot 1 and a control terminal, wherein the multi-legged robot 1 is provided with a jack 2, a sensor, a communication component, an IMU inertia measurement unit and a battery,

the battery supplies power for the communication assembly, the motors, the sensors and the IMU inertia measurement unit on the plurality of groups of robots 1.

The control terminal can be any device capable of being remotely operated, such as a computer, a server and the like.

The communication component is in communication connection with the control terminal, so that the control terminal can control the motion of the multi-legged robot 1.

The sensor is used for discerning the topography, transmits topography information to control terminal through the communication subassembly for operating personnel can learn the state information of robot, and then controls the robot through control terminal.

The IMU inertial measurement unit is used for obtaining the attitude, speed and displacement information of the robot so as to assist the robot to keep stable standing and walking.

Further, in the present invention, the specific structure and type of the communication component are not particularly limited, and preferably, the communication component is a wireless communication module, and those skilled in the art can select the communication component according to actual needs, for example, a bluetooth module, a WIFI module, a ZigBee module, an NB-IOT module, and the like are adopted.

In a preferred embodiment, the sensor comprises a laser radar, and the laser radar scans the surrounding environment of the robot to establish a three-dimensional map according to which the robot is controlled by an operator.

In a preferred embodiment, the sensor further comprises a camera, preferably a binocular camera, and the camera collects images in the walking direction to identify whether the sole landing point has an obstacle or a pot hole.

In the present invention, the type of the IMU inertial measurement unit is not particularly limited, and those skilled in the art can select the IMU inertial measurement unit according to actual needs, for example, 6-axis IMU, 9-axis IMU, and the like.

In the invention, the robot is a multi-legged robot, the multi-legged robot is used as a moving component of a disaster relief system, compared with a traditional crawler-type moving component, the robot has greater advantages in the aspect of crossing terrain obstacles, the legged moving robot has low requirements on walking pavements, can cross obstacles, travels on various rugged and uneven complex pavements, and has stronger applicability to post-disaster chaotic terrains, and the multi-legged bionic robot has high maneuverability and loading capacity, and is beneficial to rapid rescue and relief.

Further, the multi-feet may be four-feet, six-feet, etc., and the present invention is not limited thereto, and those skilled in the art may select the multi-feet based on experience.

Further, the multi-legged robot 1 includes a frame 12 and legs 11 connected to the frame 12, as shown in fig. 1.

Further, the leg 11 includes a thigh portion 111, a shank portion 112 and a pull rod 113, the upper end of the thigh portion 111 is provided with a thigh steering gear 114, as shown in fig. 2, the thigh steering gear 114 is fixed on the frame 12.

Furthermore, the lower end of the thigh part 111 is hinged with the lower leg part 112, one end of the pull rod 113 is hinged with the upper end of the lower leg part 112, the lower leg part 112 is pulled through the pull rod 113, so that the thigh part 111 and the lower leg part 112 can rotate relatively, the extension and retraction of the stand 11 are realized, and the walking process is further realized.

Preferably, the pull rod 113 is pulled through a pull rod steering engine 115, the pull rod steering engine 115 is hinged to the pull rod 113 through a steering engine rod, and when the pull rod steering engine 115 rotates, the pull rod 113 pulls the upper end of the lower leg part 112, so that the leg 11 stretches.

More preferably, the pull rod steering engine 115 is mounted on the side wall of the thigh part 111, and the steering engine rod 1151 is hinged to the pull rod 113.

In the invention, the pull rod 113, the thigh part 111 and the shank part 112 are connected to form a double-rocker mechanism, and the pull rod 113 is driven by the pull rod steering engine 115 with large torque, so that the load capacity of the leg 11 can be greatly improved.

In the invention, the disaster relief system mainly acts as a support for the heavy objects, and the heavy objects need to be lifted to let disaster relief personnel enter or ensure the safety of trapped personnel, so that the load bearing capacity of the multi-legged robot 1 is greatly required, however, the traditional multi-legged robot 1 has insufficient structural strength and the load capacity cannot meet the requirement.

In view of the above, the inventor has conducted intensive research on the structure of the leg 11, and preferably, as shown in fig. 3, the thigh portion 111 and/or the lower leg portion 112 include two base plates 1111 having the same structure, and the structure of the two base plates 1111 is adopted, so that the weight of the leg 11 is greatly reduced, the power consumption of the thigh steering engine 114 and the pull rod steering engine 115 is reduced, and the working time of the disaster relief system is further prolonged.

Further, a reinforcing rib 1112 is provided between the two base plates 1111, and the two base plates 1111 are connected by the reinforcing rib 1112 to improve the overall structural strength.

In a preferred embodiment, the base plate 1111 is hollowed out to reduce the weight of the leg 11.

Preferably, the substrate 1111 and the reinforcing ribs 1112 are made of aluminum alloy, so that the structural strength of the multi-legged robot is greatly improved on the premise that the whole weight meets the practical engineering application requirements.

In a more preferred embodiment, of the two base plates 1111, the upper end of the outer base plate 1111 is further provided with a machine body thigh connecting key 116, one end of the machine body thigh connecting key 116 is fixed on the machine frame 12, and the other end of the machine body thigh connecting key 116 is hinged with the outer base plate 1111.

According to a preferred embodiment of the present invention, the thigh portion 111 is hinged to the lower leg portion 112 through a bearing 118, and the thigh portion 111 is hinged to the thigh steering engine 114 through a bearing 118.

In a more preferred embodiment, the thigh link 116 is hinged to the outer base 1111 via a bearing 118.

As the stress of the thigh root, the shank root and the joint of the shank and the machine body is large, the mechanical friction can be greatly reduced through the hinged form of the bearing, the application safety is improved, and the service life is prolonged.

In a preferred embodiment, a sole 117 is disposed at the bottom end of the lower leg portion 112, and preferably, the sole 117 is made of a non-metal organic material, so as to increase the friction force with the ground, and simultaneously, play a role in shock absorption and increase the safety performance of the leg structure.

More preferably, the cross section of the sole 117 is circular arc, so as to further improve the vibration damping effect.

According to the present invention, a force sensor is provided at the sole 117 to detect whether the robot sole touches the ground.

The frame 12 includes frame tubes 121, end plates 122, and a base plate 123, as shown in fig. 4, and further, both ends of the plurality of frame tubes 121 are fixed by the end plates 122.

In a preferred embodiment, the frame tube 121 and the end plate 122 are connected by an interference fit.

Preferably, the plurality of frame tubes 121 are arranged in two layers, and the base plate 123 is arranged on the lower frame tube 121 for receiving the jack 2.

In the invention, the framework structure of the frame 12 formed by the frame pipe 121 and the end plate 122 is adopted, so that the load capacity of the frame 12 is ensured, the overall weight of the frame 12 is reduced, and the load pressure on the legs 11 is reduced.

In a preferred embodiment, the frame tube 121 is a carbon fiber tube, which has the advantages of high strength, corrosion resistance, light weight, etc., and reduces the load on the leg of the robot dog while ensuring the structural strength of the frame, and facilitates the installation of the circuit board and the related control components.

In a preferred embodiment, the base plate 123 is secured to the frame tube 121 by bolts 125.

In a preferred embodiment, a leg swing steering engine 124 is further provided on the frame 12, and the leg swing steering engine 124 is connected with the leg 11, so that the leg 11 can swing left and right.

More preferably, the leg outward swing steering engine 124 is arranged on the bolt 125 to reduce the number of threaded holes on the substrate 123, so that the substrate structure is more reasonable and the mechanical performance is stronger.

Preferably, the leg outer swing steering engine 124 is further connected with the frame tube 121, and more preferably, the leg outer swing steering engine 124 is in interference fit with the frame tube 121 and the bolt 125, so that the structural strength of the connection part of the leg and the frame is further enhanced.

The jack 2 is arranged on the base plate 123, preferably fixed to the base plate 123 by means of bolts.

In a preferred embodiment, the jack 2 further has a thin plate 21 at the upper end, and as shown in fig. 1, the thin plate 21 is fixedly connected to the upper frame tube 121, so as to further improve the connection strength between the jack 2 and the multi-legged robot 1.

The jack is preferably a hydraulic jack.

Further, a jack steering engine 22 is arranged on the frame 12, and the jack steering engine 22 drives the hydraulic piston rod to perform lifting and pressing actions, so that the jack is lifted.

In a preferred embodiment, the jack actuator 22 is connected with a hydraulic piston rod 24 through a double-rocker structure assembly 23, as shown in fig. 5 and 6.

Specifically, the double-rocker structure component 23 includes a rocker 231, a connecting rod 232 and a power pressure rod 233, one end of the rocker 231 is connected with the jack steering engine 22, the other end of the rocker is hinged to the power pressure rod 233 through the connecting rod 232, and the power pressure rod 233 is hinged to the hydraulic piston rod, so that when the jack steering engine 22 swings at a fixed angle, the power pressure rod 233 is driven to swing, and the hydraulic piston rod is driven to do linear reciprocating motion.

In a preferred embodiment, a reinforcing rocker 234 is further arranged between the rocker 231 and the connecting rod 232, and the inventor finds that because the geometric length and the structural strength of the rocker 231 per se do not meet the practical application requirements, in the invention, the rocker 234 is additionally arranged between the rocker 231 and the connecting rod 232, so that the application requirements of the geometric size and the structural strength are met, and the jack lifting function of the jack is ensured.

In a preferred embodiment, the section of the power compression bar 233 is in a V-like shape, the middle of the V-shape is hinged to the hydraulic piston rod, and two sides of the V-shape are perpendicular to each other, so that on one hand, the occupied space of the double-rocker structure assembly is reduced, on the other hand, the output force is increased, and the lifting function of the jack is ensured.

According to the invention, the oil valve 25 of the jack 2 is connected with the landing steering engine 26, and the landing steering engine 26 drives the oil valve 25 to rotate, so that the oil valve 25 is opened and closed.

According to the present invention, the communication module and the battery are disposed on the upper surface of the substrate 123 to protect the communication module and the battery.

Further, the IMU inertial measurement unit is disposed on the upper surface of the substrate 123 to measure attitude, velocity, and displacement information of the substrate 123 to ensure stability of the substrate 123.

On the other hand, the invention also provides an automatic jacking disaster relief method based on the multi-legged robot, which is particularly suitable for rescuing in a narrow environment where disaster relief personnel are difficult to directly enter.

The method comprises the following steps:

s1, detecting the environment and establishing a three-dimensional map;

s2, moving the robot to a position to be jacked;

and S3, lifting up the heavy object for rescue.

Because the robot works in a narrow and small area, the multiple visual lines of the area are blocked, and the terrain is not clear, the robot needs to perform environment detection on the working area in the rescue process, establish a three-dimensional map, and provide necessary information for operators and self movement.

In step S1, the environment detection is preferably implemented by scanning with a laser radar, and further, a three-dimensional map is established based on the laser radar, and an operator can determine a current terrain control heading direction, a jacking position, and the like based on the established map, and perform obstacle avoidance operation during the traveling process.

In the present invention, the specific method for building the three-dimensional map is not particularly limited, and those skilled in the art can freely set the method according to experience or needs, for example, the building of the three-dimensional map is realized by a load-SLAM algorithm.

After the three-dimensional map is created, in step S2, the operator determines the terrain according to the three-dimensional map, and operates the robot to move to a target position, where the operator needs to lift the robot for rescue.

Further, different from other places, the disaster-stricken site has uneven ground, more sundries, gaps and the like, the ground is unstable, the ground can be loosened, and the difficulty of the invention is how to keep the stability of the robot body in the moving process and prevent the robot from turning over.

In the invention, the robot comprises the following components in the moving process:

walking stability control; and

and (5) stably controlling standing.

According to the invention, because the weight of the jack is large, the gravity center of the robot is concentrated at the central position of the jack, and the robot needs to carry out walking stability control in the moving process.

In the walking process of the multi-legged robot, each step belongs to static gait, and the stable walking of the robot cannot be ensured through dynamic stability.

Furthermore, the multi-legged robot has at least three legs which land on the ground in the walking process to support the robot, and a triangular stable area is formed between the three legs.

In the present invention, the walking stability control is realized by defining the center of gravity in a stable region.

More preferably, the center of gravity is defined in the safety stabilized area.

The safe stable region is a region with a fixed edge range of the stable region removed, and the removed edge range is called a stable margin S_vThe stability margin S_vThe specific numerical value of (c) can be obtained by a plurality of tests, and is not particularly limited in the present invention, as shown in fig. 8, in which a shaded portion is a safety stable region.

Furthermore, in the walking process, the gravity center is always positioned in the safe and stable area by planning the motion trail of the gravity center, so that the robot does not turn over or the like.

Further preferably, in the present invention, the stability margin S is set by_mAs a measure of the stability of the robot during its movement, the stability margin S is made_mThe table being greater than the stability threshold Q, i.e. S_m>Q, to ensure stability.

The specific value of the stability threshold Q may be selected by a person skilled in the art based on experience, and is not limited in the present invention.

In a preferred embodiment, the stability margin S_mExpressed as:

S_m＝min(S_m1,S_m2,S_m3) (A)

Wherein S is_m1,S_m2,S_m3The distances from the center of gravity to the three sides of the safety stabilized area, respectively, are shown in fig. 9.

In a preferred embodiment, the robot is moved with a stability margin S when walking_mAnd controlling the walking track of the robot for the gravity center track.

The mode can ensure that the stability of the gravity center is maximum, and is suitable for being used when large vibration is possible on the ground.

However, although this method ensures the maximum stability of the robot walking, it causes the robot to frequently move back and forth during walking, as shown by the trace 1 in fig. 10, which is not beneficial to the control and walking of the robot.

In another preferred embodiment, the trajectory is optimized, and a stability margin S is selected during the walking process_mAnd a connecting line of the forward and backward moving midpoints of the tracks is a gravity center moving control track, and a motion planning coordinate is obtained according to the control track.

As shown in FIG. 10, the stability margin S_mThe track is track 1, the middle points of the forward and backward movement of the track 1 are taken, the middle points are connected to form track 2, and the track 2 is used as a gravity center movement control track, so that the high stability margin of the robot in the moving process is ensured, and the walking speed is increased.

The motion planning coordinates comprise the positions of the soles of the robots and the rotation angles of the joints.

Further, the method of obtaining the motion planning coordinate according to the control trajectory is a conventional technical means in the art, and is not described in detail in the present invention, and a person skilled in the art can design the motion planning coordinate according to experience.

Furthermore, because the ground in the disaster area is uneven, different feet of the robot are difficult to be on the same horizontal plane, and the motion planning coordinates of the robot need to be supplemented in the walking process, so that the robot keeps stable.

According to the invention, each foot of the multi-legged robot is provided with 3 joints, namely a shank and thigh connecting joint, a thigh up-down movable joint and a thigh outward swinging joint, the simplified drawing is shown in figure 11, the 3 joints respectively correspond to a pull rod steering engine 115, a thigh steering engine 114 and a leg outward swinging steering engine 124, the joint angle can be adjusted by adjusting the rotation amount of the steering engines, and the thigh outward swinging joint angle is represented as theta₁The angle of the upper and lower thigh joints is represented by θ₂The joint connecting the lower leg and the thigh is denoted by θ₃。

Further, in the present invention, the distance from the position where the thigh part and the leg part outward swing steering engine are connected to the position where the leg part outward swing steering engine is connected to the base plate is represented as l₁The total thigh length is denoted by l₂The total length of the lower leg is denoted by l₃。

Because the standing position of the robot is unstable, the mode of determining the joint control quantity through the sole landing position in the walking of the traditional robot is not suitable for the invention, and how to obtain the control quantity of each joint under the condition that the sole plane angle is unknown is a difficult point of the invention.

Specifically, during the movement, self-stabilization control is performed so that the robot base plate remains stable.

The self-stabilization control comprises the following substeps:

s211, obtaining the angle of each joint of the walking foot of the robot;

and S212, compensating the rotation angle of each joint.

In step S211, the angles of the joints of the foot are inversely solved according to the size and the sole position of the substrate.

In the present invention, the angle of each joint is obtained by inverse solving the formula. The inverse solution is formulated as:

wherein

θ₁、θ₂、θ₃The angle of the three joints on the foot, x₁、y₁、z₁To plan the position of the sole in coordinates for the movement,/₃For the lower leg being long, /)₂The thigh length is d, and the width of the outer hem is d.

In step S212, the navigation angle of the substrate relative to the horizontal plane is measured by the IMU inertial unit, and the angles of the joints of the walking foot of the robot are adjusted by using the real-time state of the substrate, so that the substrate is in a stable state.

In the invention, the navigation angle includes yaw angle yaw, pitch angle pitch and roll angle of the substrate plane in the world coordinate system, and the navigation angle represents the posture of the robot substrate in the world coordinate system.

Further, for convenience of description, a four-legged robot will be taken as an example, and the control method of the different legs of the other multi-legged robot is the same as that of the four-legged robot.

Further, for convenience of description, F1 denotes a walking sole as shown in fig. 7, where the robot forward direction is the X direction, the height direction is the Y direction, and the swing direction is the Z direction.

Further, before walking, when the robot is in a stable state, the position of the base plate is shown by a dotted line, O 'represents the central point of the base plate, and K' represents the connecting position of the base plate and the leg outer swing rudder;

when the robot base plate rotates during walking, the position of the base plate is shown as a solid line in the figure, O represents the central point of the base plate after rotation, and K' represents the connecting position of the base plate after rotation and the leg swing steering machine.

According to the present invention, when the ground is unstable, the substrate is rotated, and the rotation matrix a can be expressed as

A ═ R (x, roll) × R (z, pitch) × R (y, yaw) (four)

Wherein the content of the first and second substances,

the world coordinate system can be obtained by the rotation matrix

Further, the control trajectory of the foot under the world coordinate system is:

wherein the content of the first and second substances,and obtaining the sole position coordinate and the centroid position coordinate in the world coordinate system by subtraction.

The control acceleration of the foot under the robot body coordinate system is as follows:

wherein the content of the first and second substances,is a constant value and is related only to the length and width of the substrate.

Acceleration vector obtained by equation (eight)Substituting the inverse formula to obtain the joint angle of each joint and further obtain the rotation angle of each joint, so that the substrate is kept horizontal.

Further preferably, in formula (iv), the specific value of the pitch angle pitch does not directly adopt the value detected by the IMU inertial unit, but performs PI control on the detected value, so as to enhance the anti-interference capability of the robot and better adapt to uneven terrain.

Specifically, the input amount of the pitch angle pitch is:

pitchin(t)＝k_P×pitch′(t)+k_Ix Σ pitch' (t) (nine)

Where pitch' (t) represents the pitch angle before substrate rotation, k_PThe preferred ratio is 0.9-1.2, k_IThe integral adjustment coefficient is preferably 0.1-0.2, and t represents sampling time, namely the time for acquiring the attitude angle once by the IMU inertial unit, and is generally 20 ms-50 ms.

In a preferred embodiment, during the movement of the robot, the walking foot is also subjected to plantar touchdown detection by means of a force sensor.

When the walking foot swings, when sole touchdown is detected, the walking foot stops moving downwards, only the forward direction movement is carried out, and the sole height of the walking foot is obtained according to the time between the beginning of walking and the sole touchdown, so that the height of the walking foot is maintained in the subsequent forward direction movement, and the robot is kept horizontal on a complex road surface.

Through experiments, the method has the advantages that the base plate can be always kept stable when the robot walks on uneven ground, the robot can still stably walk when the ground inclines for more than 20 degrees, and the robot can be kept stable when the inclination angle caused by vibration or shaking is not more than 15 degrees even if the ground suddenly vibrates violently or a sole support slides in the walking process.

In a preferred embodiment, a camera, preferably a binocular camera, is further arranged on the robot, and images in the walking direction are collected through the camera to identify whether barriers or pits exist on a sole falling point in advance so as to prevent the sole of the robot from sliding or falling and being clamped into the pits.

Preferably, the recognition is performed by processing the captured image by an OpenCV vision tool.

More preferably, the images are identified and matched through feature point detection SIFT, obstacles and pot holes are identified and transmitted to an operator, and the operator is reminded to pay attention to avoidance.

In the invention, because the disaster area with unstable ground is faced, the robot can have ground shaking and other conditions in the standing process, such as loosening and sinking of the standing part, and the robot needs to be dynamically adjusted at any time to ensure the standing stability of the robot.

When the robot stands and the ground is sunk, the sole force sensors of the robot detect that a certain sole is lifted off the ground, and the stand of the lifted foot is stably controlled to keep the stability of the robot.

Specifically, the standing stability control includes the following sub-steps:

s213, adjusting joints of each foot to enable the robot substrate to be stable;

and S214, grounding the ground.

In step S213, the angles of the joints of the respective feet of the robot are adjusted using the real-time state of the substrate by measuring the navigation angle of the substrate with respect to the horizontal plane through the IMU inertial unit so that the substrate is in a stationary state.

One foot of the robot is taken as an example for explanation, and the control method of the other feet is the same as that of the foot, as shown in fig. 7.

Further, before the ground is sunk, when the robot is in a stable state, the position of the base plate is shown by a dotted line, O 'represents the central point of the base plate, and K' represents the connecting position of the base plate and the leg outward-swinging rudder;

when the ground is sunk and the robot base plate rotates, the position of the base plate is shown as a solid line in the figure, O represents the central point of the base plate after rotation, and K' represents the connecting position of the base plate after rotation and the leg swing steering engine.

According to the present invention, when the ground is unstable, the substrate is rotated, and the rotation matrix a can be expressed as

A ═ R (x, roll) × R (z, pitch) × R (y, yaw) (four)

Wherein the content of the first and second substances,

the world coordinate system can be obtained by the rotation matrix

Further, the control trajectory of the foot under the world coordinate system is:

wherein the content of the first and second substances,and subtracting the position coordinate of the sole and the position coordinate of the centroid under the world coordinate system to obtain the position coordinate of the sole, wherein the position coordinate of the sole is the foot coordinate recorded in the walking process.

The control acceleration of the foot in the fuselage coordinate system caused by the ground sag is:

wherein the content of the first and second substances,is a constant value and is related only to the length and width of the substrate.

Acceleration vector obtained by equation (eight)Substituting the inverse formula to obtain the joint angle of each joint and further obtain the rotation angle of each joint, so that the substrate is kept horizontal.

Further preferably, in formula (iv), the specific value of the pitch angle pitch does not directly adopt the value detected by the IMU inertial unit, but performs PI control on the detected value, so as to enhance the anti-interference capability of the robot and better adapt to uneven terrain.

Specifically, the input amount of the pitch angle pitch is:

pitchin(t)＝k_P×pitch′(t)+k_Ix Σ pitch' (t) (nine)

Where pitch' (t) represents the pitch angle before substrate rotation, k_PThe preferred ratio is 0.9-1.2, k_IThe integral adjustment coefficient is preferably 0.1-0.2, and t represents sampling time, namely the time for acquiring the attitude angle once by the IMU inertial unit, and is generally 20 ms-50 ms.

In step S214, the ground contact foot is compensated and controlled so that the ground contact foot touches the ground.

Whether the sole contacts the ground is judged through the force sensor, specifically, when the sole does not contact the ground, the foot is firstly controlled to fall vertically:

if the sole contacts the ground in the falling process, stopping the foot from falling, and enabling the robot to stand stably;

if the sole of the foot still does not contact the ground after reaching the mechanical limit of the foot, the position of the sole of the foot before the ground is sunk is taken as the center, and the position of the ground closest to the center position is taken as a new landing point of the foot.

Further, the ground position closest to the center position is detected by a sensor mounted on the robot, preferably by a camera mounted thereon.

Through experiments, the robot can still keep stable under the condition that the ground surface inclines by more than 40 degrees, and in the standing process, even if the ground surface suddenly generates violent vibration or sole support sliding, the robot can keep stable as long as the caused vibration or shaking is not more than 60 degrees in the pitching direction, not more than 40 degrees in the yawing direction and not more than 50 degrees in the rolling angle direction.

Further, in step S2, the operator determines whether the position to be jacked is flat or not according to the three-dimensional map, and searches for a relatively flat position, so that the robot moves to the position to facilitate the subsequent jacking operation.

In step S3, the following substeps are included:

s31, the robot retracts the multiple feet to enable the lower surface of the substrate to be in contact with the ground;

and S32, operating a jack steering engine to lift the jack.

In step S31, the bottom surface of the substrate is in direct contact with the ground, so that the robot does not bear any pressure during the jacking process, damage to the robot is avoided, and the mechanical strength requirement of the robot is reduced.

The invention has been described in detail with reference to specific embodiments and illustrative examples, but the description is not intended to be construed in a limiting sense. Those skilled in the art will appreciate that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, which fall within the scope of the present invention.