Double-drive cooperative steering driving system

Abstract

The invention discloses a double-drive cooperative steering driving system, which belongs to the technical field of double drive, and comprises a driving wheel I and a driving wheel II which are distributed in parallel, a driving wheel mounting frame is arranged at the upper ends of the driving wheel I and the driving wheel II, the driving wheel mounting frame is arranged in a machine body, and a steering handle is arranged above the machine body. A steering shaft is arranged at the lower end of the steering handle and is rotatably arranged on the machine body; an electric control unit is further arranged on the machine body, and the electric control unit is electrically connected with the sensor module; the electric control unit is used for independently controlling the rotating direction and rotating speed of the driving wheel I and the driving wheel II; the sensor module is used for collecting motion states and environment data of the steering shaft, the first driving wheel and the second driving wheel and feeding back the data to the electric control unit. According to the double-drive cooperative steering driving system, the rotating speed and the rotating direction of the motors of the two parallel driving wheels are independently controlled, so that the structure is simplified, the cost is reduced, and the steering flexibility is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of dual-drive, and in particular to a dual-drive collaborative steering drive system. Background Art

[0002] A forklift refers to various wheeled handling vehicles for loading, unloading, stacking, and short-distance transportation of palletized goods. It is widely used in factory workshops, warehouses, distribution centers, ports, stations, airports, freight yards, etc., and can enter the cabin, carriage, and container for loading and unloading of palletized goods. It is an essential equipment for pallet transportation and container transportation. However, during the handling of large-tonnage goods, in order to drive the large-tonnage forklift to travel and turn, a powerful power output is required, which requires the steering system to provide a greater steering force. If the steering force is insufficient, it will cause the driver to operate laboriously and even unable to achieve flexible steering, affecting work efficiency and safety. The traditional steering technology has the following problems: 1) High energy consumption of the hydraulic steering system: The hydraulic pump needs to be continuously driven by an engine or a motor. Even when the vehicle is stationary or the steering is not operating, the oil pump still idles and consumes energy, resulting in relatively high energy consumption; 2) High cost of omnidirectional wheels: Special wheel bodies such as Mecanum wheels can achieve omnidirectional movement, but they have complex structures, high costs, and poor durability; 3) High cost of the electric steering system: The technology content of the electric power steering system is relatively high, and its components include motors, sensors, control modules, etc., resulting in a relatively high cost. Based on this, the present invention proposes a dual-drive collaborative steering drive system. Summary of the Invention

[0003] The purpose of the present invention is to provide a dual-drive collaborative steering drive system to solve the above-mentioned problems.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions: A dual-drive collaborative steering drive system of the present invention includes a drive wheel one and a drive wheel two that are distributed in parallel. The upper ends of the drive wheel one and the drive wheel two are provided with drive wheel mounting brackets, and the drive wheel mounting brackets are arranged in the machine body. A steering handle is provided above the machine body, and a steering shaft is provided at the lower end of the steering handle. The steering shaft is rotatably arranged on the machine body; an electronic control unit is also provided on the machine body, and the electronic control unit is electrically connected to the sensor module; The electronic control unit is used to independently control the rotation direction and speed of the drive wheel one and the drive wheel two; the sensor module is used to collect the motion states and environmental data of the steering shaft, the drive wheel one, and the drive wheel two and feedback them to the electronic control unit; the electronic control unit dynamically generates control signals for driving the drive wheel one and the drive wheel two according to the steering signal and the data of the sensor module to achieve differential steering.

[0005] Further, the first driving wheel and the second driving wheel are respectively driven to rotate by the first motor and the second motor, and the first motor and the second motor are both electrically connected to the electronic control unit.

[0006] Further, both the first motor and the second motor are reversible motors.

[0007] Further, a first balancing mechanism is provided on the driving wheel mounting bracket. The first balancing mechanism includes balancing shaft mounting plates symmetrically arranged at the center positions of the front and rear end faces of the driving wheel mounting bracket. A shaft hole is provided at the center position of the balancing shaft mounting plate. A balancing shaft is arranged between the front and rear shaft holes, and the inner diameter of the shaft hole is larger than the outer diameter of the balancing shaft.

[0008] Further, a second balancing mechanism is provided at the upper end of the first balancing mechanism, and the other end of the second balancing mechanism is connected to the machine body; the second balancing mechanism includes a guide post arranged above the driving wheel mounting bracket. A top plate is provided at the upper end of the guide post, and the lower end of the guide post is fixedly connected to the balancing shaft; a spring is sleeved on the guide post. A connecting plate is slidably arranged on the guide post between the upper end face of the spring and the top plate. One end of the connecting plate away from the guide post is connected to the machine body, and the lower end face of the spring is connected to a spring bottom support sleeved on the lower part of the guide post. The spring bottom support is located above the driving wheel mounting bracket; guide rods for restricting the up and down movement of the connecting plate are symmetrically arranged on the lower end face of the top plate, and the connecting plate and the guide rods are slidably connected.

[0009] Further, a third balancing mechanism is provided on one side of the second balancing mechanism away from the driving wheel mounting bracket. The third balancing mechanism includes a pressing plate slidably sleeved on the guide post. The pressing plate is located below the spring bottom support; a balancing rod is provided on the lower end face of one end of the pressing plate away from the guide post. The pressing plate is vertically distributed with the balancing rod and is located at the middle position of the balancing rod; hinge plates are symmetrically sleeved at both ends of the balancing rod, and the other end of the hinge plate is hinged to a balancing wheel mounting plate, and a balancing wheel is provided at the lower end of the balancing wheel mounting plate.

[0010] Further, the sensor module includes an angle sensor for detecting the rotation angle of the steering shaft, an encoder for calibrating the rotation angle positions of the first driving wheel and the second driving wheel, and a wheel speed encoder for detecting the rotational speeds of the first driving wheel and the second driving wheel.

[0011] Compared with the prior art, the beneficial technical effects of the present invention are: The structure of the dual-drive collaborative steering drive system of the present invention is simplified: the traditional steering mechanism is cancelled, and it only relies on motor control, reducing the manufacturing cost and failure rate; high-precision control: combining sensor feedback to achieve closed-loop control, adapting to complex terrains. In short, the dual-drive collaborative steering drive system of the present invention simplifies the structure, reduces the cost and improves the steering flexibility by independently controlling the motor speeds and rotation directions of two parallel drive wheels. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention will be further described below in conjunction with the drawings.

[0013] Figure 1 Schematic diagram of the structure of the dual-drive collaborative steering drive system of the present invention Figure 1 ; Figure 2 Schematic diagram of the structure of the dual-drive collaborative steering drive system of the present invention Figure 2 ; Figure 3 Schematic diagram of the structures of balance mechanism two and balance mechanism three; Figure 4 Schematic diagram of the structure of balance mechanism one; Figure 5 Logic flowchart of the control of the electronic control unit; Figure 6 Principle diagram of the differential turning of the drive wheel; Description of the reference numerals in the drawings: 1. Steering handle; 2. Steering shaft; 3. Electronic control unit; 4. Drive wheel mounting bracket; 5. Drive wheel one; 6. Drive wheel two; 7. Balance mechanism two; 8. Balance mechanism one; 9. Balance mechanism three; 10. Body. 701 Guide post; 702. Spring bottom support; 703. Spring; 704. Guide rod; 705. Connecting plate; 706. Top plate. 801. Balance shaft mounting plate; 802. Balance shaft; 803. Shaft hole. 901. Balance rod; 902. Hinge plate; 903. Balance wheel mounting plate; 904. Balance wheel; 905. Pressure plate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] As Figures 1-6As shown in the figure, a dual-drive collaborative steering drive system includes a first drive wheel 5 and a second drive wheel 6 that are distributed in parallel. A drive wheel mounting bracket 4 is fixedly installed at the upper ends of the first drive wheel 5 and the second drive wheel 6, and the drive wheel mounting bracket 4 is installed in the body 10. Above the body 10, a steering handle 1 is installed. The lower end of the steering handle 1 is installed with a steering shaft 2, and the steering shaft 2 is rotatably installed on the body 10. An electronic control unit 3 is also installed on the body 10, and the electronic control unit 3 is electrically connected to the sensor module. The first drive wheel 5 and the second drive wheel 6 are respectively driven to rotate by a first motor and a second motor. Both the first motor and the second motor are reversible motors, which are used to drive the first drive wheel 5 and the second drive wheel 6 to rotate forward and backward, and the rotational speed can be independently adjusted (from 0 to the maximum rotational speed); both the first motor and the second motor are electrically connected to the electronic control unit 3, receive steering instructions, dynamically calculate the target rotational speeds and directions of the two wheels, and output control signals.

[0015] The electronic control unit 3 is used to independently control the rotational directions and speeds of the first drive wheel 5 and the second drive wheel 6; the sensor module is used to collect the motion states and environmental data of the steering shaft 2, the first drive wheel 5 and the second drive wheel 6 and feedback them to the electronic control unit 3. The electronic control unit 3 dynamically generates control signals for driving the first drive wheel 5 and the second drive wheel 6 according to the steering signal and the data of the sensor module to achieve differential steering. The sensor module includes an angle sensor for detecting the rotation angle of the steering shaft 2, an encoder for calibrating the rotation angle positions of the first drive wheel 5 and the second drive wheel 6, and a wheel speed encoder for detecting the rotational speeds of the first drive wheel 5 and the second drive wheel 6.

[0016] The main purpose of the encoder to calibrate the rotation angle position at all times is to ensure the motion accuracy, stability and anti-interference ability of the system. Specifically: 1) Correct motion deviation During actual operation, the rotational speeds of the two drive wheels may be inconsistent due to reasons such as differences in motor performance, uneven load, changes in ground friction or tire slippage. The encoder calibrates the midpoint position in real time, which can avoid the occurrence of the phenomenon that the small speed difference between the two drive wheels causes the device to deviate from the predetermined trajectory (for example, it cannot maintain a straight line) due to accumulation over time.

[0017] 2) Maintain attitude stability In the differential steering system of this technical solution, the deviation of the midpoint position will directly affect the calculation of the steering angle. The encoder can dynamically adjust the torque difference between the two wheels by real-time feedback of the midpoint state to prevent the body from deflecting or shaking.

[0018] 3) Suppress error accumulation The wheel speed error of the drive wheel will cause a calculation deviation of the midpoint position. After long-term accumulation, the positioning accuracy will drop significantly. By calibrating the midpoint in real time with the encoder, the error can be reset to avoid "drifting further and further off course".

[0019] 4) Adapt to complex environments During driving on uneven ground, uneven forces on the two drive wheels may cause the midpoint to shift. For example, when one wheel gets stuck in a low-friction area (such as a slippery ground). Real-time calibration by the encoder can reduce the speed of the other wheel to prevent the device from getting out of control.

[0020] 5) Improve control response speed When the encoder detects a sudden change in the midpoint position due to external interference (such as a collision), the system can immediately adjust the differential speed of the two wheels to quickly restore balance or path tracking.

[0021] A first balancing mechanism 8 is installed on the drive wheel mounting bracket 4. The first balancing mechanism 8 can be installed above or below the drive wheel mounting bracket 4. The first balancing mechanism 8 includes balancing shaft mounting plates 801 symmetrically installed at the center positions of the front and rear end faces of the drive wheel mounting bracket 4, and the balancing shaft mounting plates 801 are located below the drive wheel mounting bracket 4. A shaft hole 803 is provided at the center position of the balancing shaft mounting plate 801, and a balancing shaft 802 is installed between the front and rear shaft holes 803. The inner diameter of the shaft hole 803 is larger than the outer diameter of the balancing shaft 802. Specifically, when running on an uneven road surface, when one drive wheel is lifted upward due to a road bump, the other drive wheel is depressed. At this time, under the action of the self-gravity of the body 10, the first balancing mechanism 8 rotates around the balancing shaft 802 through the shaft hole 803, causing the drive wheel mounting bracket 4 to rotate around the balancing shaft 802. Under the lever action, it ensures that the two drive wheels maintain the ground pressure, thereby maintaining the overall stability of the vehicle.

[0022] In another embodiment, a second balance mechanism 7 is installed at the upper end of the first balance mechanism 8, and the other end of the second balance mechanism 7 is connected to the body 10. The second balance mechanism 7 includes a guide post 701 installed above the drive wheel mounting bracket 4. The upper end of the guide post 701 is installed with a top plate 706. The lower end of the guide post 701 slidably passes through the drive wheel mounting bracket 4 and is fixedly connected to the balance shaft 802 (in this embodiment, the balance shaft 802 is located below the drive wheel mounting bracket 4). A spring 703 is sleeved on the guide post 701. A connecting plate 705 is slidably installed on the guide post 701 between the upper end surface of the spring 703 and the top plate 706. One end of the connecting plate 705 away from the guide post 701 is connected to the body 10. The lower end surface of the spring 703 is connected to a spring bottom support 702 sleeved on the lower part of the guide post 701. The spring bottom support 702 is located above the drive wheel mounting bracket 4. Guide rods 704 for restricting the up and down movement of the connecting plate 705 are symmetrically installed on the lower end surface of the top plate 706. The connecting plate 705 and the guide rods 704 are slidably connected. When running on an uneven road surface, the drive wheel mounting bracket 4 jolts, driving the guide post 701 to move up and down. When it moves, it will compress the spring 703. According to its own elasticity, the spring 703 will give a reverse pressure to the drive wheel mounting bracket 4, and then the drive wheel mounting bracket 4 will always drive the drive wheel to press tightly against the ground.

[0023] In another embodiment, a third balance mechanism 9 is installed on one side of the second balance mechanism 7 away from the drive wheel mounting bracket 4. The third balance mechanism 9 includes a pressing plate 905 slidably sleeved on the guide post 701. The pressing plate 905 is located below the spring bottom support 702. A balance rod 901 is installed on the lower end surface of one end of the pressing plate 905 away from the guide post 701. The pressing plate 905 and the balance rod 901 are perpendicularly distributed and located at the middle position of the balance rod 901. Hinge plates 902 are symmetrically sleeved at both ends of the balance rod 901. The other end of the hinge plate 902 is hingedly connected to a balance wheel mounting plate 903. A balance wheel 904 is installed at the lower end of the balance wheel mounting plate 903. When the drive wheel mounting bracket 4 jolts, according to the content described in the second balance mechanism 7 above, the spring 703 gives a reverse pressure to the drive wheel mounting bracket 4 according to its own elasticity, pressing the drive wheel tightly against the ground; at the same time, the spring 703 will also give the same pressure to the pressing plate 905, so that the balance wheels 904 on both sides of the pressing plate 905 are driven by the balance rod 901 to press tightly against the ground together, increasing the friction with the ground, avoiding slipping, and ensuring driving stability and steering performance.

[0024] The operation process of the present invention is as follows: First, the operator rotates the steering handle 1 according to the actual needs. The steering handle 1 drives the steering shaft 2 to rotate by the same angle. The angle sensor thereon detects the steering signal and transmits the signal to the electronic control unit 3; Then, the electronic control unit 3 receives the steering signal and calculates the target rotational speed difference according to the kinematic model. The formula is as follows:

[0025] As Figure 6 shown, O is the center of rotation, R is the distance from the center of rotation to the axis of symmetry of the center of the driving wheel, and L is the distance between the centers of the driving wheels; Finally, the electronic control unit 3 controls the left driving wheel to maintain the rotational speed N1, and the right driving wheel is increased to the rotational speed N2 (N2 < N1), and the device turns to the left in an arc; the encoder real-time feedbacks the rotational angle positions of the first driving wheel 5 and the second driving wheel 6 for calibrating the rotational angle; the wheel speed encoder real-time feedbacks the rotational speeds of the first driving wheel 5 and the second driving wheel 6, and the electronic control unit 3 dynamically corrects the rotational speed difference according to the signals obtained from the above feedbacks until the target angle is reached.

[0026] The embodiments described above are only descriptions of the preferred modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A dual-drive coordinated steering drive system, characterized in that: The machine comprises a driving wheel 1 (5) and a driving wheel 2 (6) which are arranged in parallel, wherein a driving wheel mounting frame (4) is arranged at the upper ends of the driving wheel 1 (5) and the driving wheel 2 (6), wherein the driving wheel mounting frame (4) is arranged in a machine body (10), wherein a steering handle (1) is arranged above the machine body (10), wherein a steering shaft (2) is arranged at the lower end of the steering handle (1), wherein the steering shaft (2) is rotatably arranged on the machine body (10); and an electric control unit (3) is also arranged on the machine body (10), wherein the electric control unit (3) is electrically connected to a sensor module; The electronic control unit (3) is used to independently control the rotation direction and rotation speed of the driving wheel one (5) and the driving wheel two (6); the sensor module is used to collect the motion state and environmental data of the steering shaft (2), the driving wheel one (5) and the driving wheel two (6) and feed them back to the electronic control unit (3); the electronic control unit (3) dynamically generates a control signal for driving the driving wheel one (5) and the driving wheel two (6) according to the steering signal and the sensor module data to realize differential steering.

2. The dual-drive coordinated steering drive system according to claim 1, characterized in that: The driving wheel 1 (5) and the driving wheel 2 (6) are driven to rotate by motor 1 and motor 2 respectively, and the motor 1 and motor 2 are both electrically connected to the electronic control unit (3).

3. The dual-drive coordinated steering drive system according to claim 2, characterized in that: The motor 1 and the motor 2 are both forward and reverse motors.

4. The dual-drive coordinated steering drive system according to claim 1, characterized in that: The driving wheel mounting frame (4) is provided with a balancing mechanism (8), the balancing mechanism (8) comprising a balancing shaft mounting plate (801) symmetrically arranged at the center position of the front and rear end surfaces of the driving wheel mounting frame (4), an axis hole (803) is opened at the center position of the balancing shaft mounting plate (801), a balancing shaft (802) is arranged between the front and rear axis holes (803), and the inner diameter of the axis hole (803) is larger than the outer diameter of the balancing shaft (802).

5. The dual-drive coordinated steering drive system according to claim 4, characterized in that: The upper end of the balancing mechanism 1 (8) is provided with a balancing mechanism 2 (7), and the other end of the balancing mechanism 2 (7) is connected to the machine body (10); the balancing mechanism 2 (7) comprises a guide column (701) arranged above the driving wheel mounting frame (4), the upper end of the guide column (701) is provided with a top plate (706), and the lower end of the guide column (701) is fixedly connected to the balancing shaft (802); a spring (703) is sleeved on the guide column (701), and a slidable spring (703) is provided on the guide column (701) between the upper end surface of the spring (703) and the top plate (706). A connecting plate (705) is provided, and one end of the connecting plate (705) away from the guide column (701) is connected to the machine body (10); the lower end surface of the spring (703) is connected to a spring bottom support (702) sleeved on the lower part of the guide column (701), and the spring bottom support (702) is located above the driving wheel mounting frame (4); and guide rods (704) for limiting the upward and downward movement of the connecting plate (705) are symmetrically provided on the lower end surface of the top plate (706), and the connecting plate (705) and the guide rods (704) are slidably connected.

6. The dual-drive coordinated steering drive system according to claim 5, characterized in that: A balancing mechanism (9) is provided on a side of the balancing mechanism (7) away from the driving wheel mounting frame (4), and the balancing mechanism (9) comprises a pressure plate (905) slidably mounted on the guide column (701), and the pressure plate (905) is located below the spring bottom support (702); a balancing rod (901) is provided on the lower end surface of one end of the pressure plate (905) away from the guide column (701), and the pressure plate (905) is vertically distributed with the balancing rod (901) and is located at the middle position of the balancing rod (901); hinged plates (902) are symmetrically mounted on both ends of the balancing rod (901), and the other end of the hinged plate (902) is hingedly connected to a balancing wheel mounting plate (903), and a balancing wheel (904) is provided at the lower end of the balancing wheel mounting plate (903).

7. The dual-drive coordinated steering drive system according to claim 1, characterized in that: The sensor module comprises an angle sensor for detecting the rotation angle of the steering shaft (2), an encoder for calibrating the rotation angle position of the driving wheel one (5) and the driving wheel two (6), and a wheel speed encoder for detecting the rotation speed of the driving wheel one (5) and the driving wheel two (6).

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