Method for controlling trolley fixed track cruising and track special element recognition through electromagnetic signals

Abstract

The invention provides a method for controlling trolley fixed-track cruise and track special element recognition through electromagnetic signals, and the method comprises the steps: collecting an inductance signal on a track, and carrying out the preprocessing of the inductance signal, and obtaining a pair of vertical inductance values and a pair of horizontal inductance values; calculating a deviation value between the trolley patrol line and the center line through the inductance value; according to the deviation value, the differential speed of the two wheels and the actual control speed of the left wheel and the right wheel are calculated in combination with the adjustable parameters of the trolley and the axial angular speed fed back by the gyroscope; the speeds of the left wheel and the right wheel are adjusted in real time through a PID controller optimized through a self-adaptive adjustment algorithm; when the trolley approaches a special element of a racing track, inductance signal change is detected, real-time monitoring is carried out through a microprocessor, whether the trolley enters a characteristic element area or not is judged in combination with gyroscope data, and corresponding response is made; and carrying out an experiment, evaluating the reliability of the proposed method, and carrying out parameter optimization according to an evaluation result. According to the invention, high stability of trolley fixed-track cruise and high adaptability to dynamic and changeable environments can be ensured.

Description

Technical Field

[0001] The present invention relates to the cross - technical field of autonomous driving technology, electromagnetic navigation and intelligent control, and particularly to a method for controlling a car to cruise along a fixed path and identifying special elements on a track by electromagnetic signals. Background Art

[0002] With the continuous progress of technology, autonomous driving technology has become an important development direction in the future transportation field. As one of the important carriers of autonomous driving technology, the performance of the navigation and control system of a three - wheeled car directly affects its application effect and safety. Although traditional electromagnetic navigation methods have achieved autonomous driving of the car to a certain extent, there are still problems such as insufficient positioning accuracy, slow response speed, and poor adaptability in the face of complex and changeable electromagnetic environments and specific terrain elements. Summary of the Invention

[0003] Aiming at the problems existing in the prior art, the present invention proposes a method for controlling a car to cruise along a fixed path and identifying special elements on a track by electromagnetic signals. By integrating inductance detection, advanced signal processing, intelligent PID control, and special element identification and response mechanisms, high - precision fixed - path cruising and intelligent navigation of a three - wheeled car in a complex electromagnetic environment are realized.

[0004] To achieve the above - mentioned technical objectives, the present invention provides the following technical solutions:

[0005] A method for controlling a car to cruise along a fixed path and identifying special elements on a track by electromagnetic signals, specifically including the following steps:

[0006] S1. Signal acquisition and processing: Collect inductance signals on the track through four inductance sensors, and pre - process them to obtain four inductance values; the inductance sensors are divided into a pair of horizontal inductance sensors and a pair of vertical inductance sensors;

[0007] S2. Error calculation: Perform fusion processing on the four inductance values obtained in step S1 to calculate the deviation value between the car's line - following and the center line, and the deviation value is denoted as E;

[0008] S3. Differential speed control: According to the magnitude of the deviation value E, combined with the adjustable parameters of the car and the axis angular velocity fed back by the gyroscope, calculate the differential speed of the two wheels. Control the steering of the car according to the differential speed of the two wheels to adapt to different turning angles, and obtain the actual control speeds of the left and right wheels of the car; the adjustable parameters include the car speed and load;

[0009] S4. Input the obtained actual control speeds of the left and right wheels into the PID controller, and adjust the motor output through the PID controller to realize real - time adjustment of the speeds of the left and right wheels; the PID controller is optimized by an adaptive adjustment algorithm, and dynamically adjusts the control parameters according to the actual driving state of the car to achieve the best control effect;

[0010] S5. When the trolley approaches a special element of the track, the inductance signal detected by the inductance sensor changes. The microprocessor monitors it in real time and combines the gyroscope data to determine whether the trolley enters the area of the special element, and makes corresponding responses according to different elements. The special elements of the track include horizontal roadblocks and rings.

[0011] S6. Conduct experiments on the trolley according to steps S1 - S5 and record the parameters of its driving trajectory, speed change, and response time, evaluate the positioning accuracy, response speed, and adaptability of the method; and optimize and adjust the trolley parameters according to the evaluation results.

[0012] Further, the pre - processing in step S1 includes:

[0013] S11. First, amplify the collected inductance signal through an operational amplifier circuit to improve the signal - to - noise ratio, and perform analog - to - digital conversion.

[0014] S12. Filter and denoise the converted digital inductance signal to obtain four pure inductance values, denoted as:

[0015] l ij ={l 11 ,l 12 ,l 21 ,l 22};

[0016] Among them, l 1j represents the inductance value in the horizontal direction, and l 2j represents the inductance value in the vertical direction.

[0017] Further, the specific calculation formula for the deviation value E in step S2 is:

[0018]

[0019] Further, step S3 specifically includes:

[0020] S31. Set the maximum deviation value E max . When the deviation value E≥E max , automatically reduce the adjustment amount of the deviation, and reduce the speed of the motor through feedback regulation to avoid violent oscillation and over - swing of the trolley.

[0021] S32. When E < E max , calculate the differential speed value of the two wheels. The specific formula is:

[0022] S dif =P + D - ω feedback ;

[0023] P = K p *E;

[0024]

[0025] ω feedback = K g *ω;

[0026] where S dif is the differential speed between the two wheels, and P, D, ω feedback are the proportional term, the derivative term, and the gyroscope feedback respectively; K p , K d , K g are the proportional term gain, the derivative term gain, and the gyroscope feedback gain respectively; ω is the angular velocity of the gyroscope feedback;

[0027] S33. Calculate the actual control speeds of the left and right wheels, that is, the target speeds of the left and right wheels, according to the differential speed value between the two wheels calculated in step S33. The specific formula is:

[0028]

[0029] where S L , S R are the actual control speeds of the left and right wheels respectively; speed l , speed r are the initial speeds of the left and right wheels respectively.

[0030] Furthermore, in step S4, the PID controller is optimized by adding an adaptive algorithm of feedforward control and differential feedforward control, and the formula is expressed as:

[0031] Output = PID_val + Fwd_val;

[0032] PID_val = kP * Err + kI * Err sum + kD * D_Err;

[0033] Fwd_val = Ffwd(Target) + D_Fwd(Target);

[0034] where Output is the control quantity finally output by the PID controller; Fwd_val is the feedforward control quantity; PID_val is the PID control quantity; kP, kI, kD are the gains of the proportional P, integral I, and derivative D parts of the PID controller respectively; Ffwd(v target ), D_Ffwd(v target ) are the outputs of the feedforward function and the differential feedforward function when the target speed is used as the input; v target is the target speed, that is, the actual control speed of the left and right wheels;

[0035] Taking the difference between the target speed and the actual speed as the input of the proportional P of the PID controller, and respectively using the accumulation and difference processing as the inputs of the integral I and the derivative D, the formula is expressed as:

[0036] Err = v target - real;

[0037] Err sum = Err' sum + Err;

[0038] D_Err = Err - Err last ;

[0039] Among them, Err is the difference between the target speed v target at the current moment and the encoder-measured speed v real ; Err sum is the accumulation of all differences up to the current moment, and Err' sum is the accumulation of all differences up to the previous moment; D_Err is the difference between the difference Err at the current moment and the difference Err last at the previous moment.

[0040] More specifically, the feedforward function and the differential feedforward function are specifically:

[0041] Feedforward function:

[0042] Ffwd(v) = K ff * v target ;

[0043] Among them, K ff is the gain of the feedforward function, and the output of the motor is pre-adjusted through the feedforward function to reduce the control error caused by the hysteresis effect;

[0044] Differential feedforward function:

[0045]

[0046] Among them, K dff is the gain of the differential feedforward function; the change speed of the target speed is pre-adjusted through the differential feedforward function to control the output, so as to reduce the system response time.

[0047] Furthermore, step S5 specifically includes:

[0048] S51. Detection and response to transverse roadblocks; using the TOF module to detect the distance to the transverse roadblock. When the distance reaches the turning set value, start turning left until the inductance information reaches the left-turn end condition, and then start turning right until the inductance information reaches the right-turn end condition to achieve bypassing the transverse roadblock;

[0049] The left-turn end condition is: when the inductance signal cannot be detected, and the inductance value is weak and close to 0, it is also considered that the inductance signal cannot be detected;

[0050] The right-turn end condition is: when the inductance values of the middle two reach 50% of the maximum value;

[0051] S52. Ring detection and response; when it is determined that all four inductance values reach the ring entry reference value, the deviation value E of the trolley's line following and the center line is affected by the center offset E dif to control the trolley to enter and pass through the ring; E dif The relationship formula with E is expressed as:

[0052] E = E'+E dif ;

[0053] where E' represents the deviation value at the previous moment, and the center offset E dif carries real-time inductance information;

[0054] The specific process is as follows:

[0055] S521. By applying the center offset E dif , change the center of the trolley's line following. When the center of the line following approaches the ring, control the trolley to enter the ring;

[0056] S522. Use the gyroscope inside the ring. When the angle of the yaw axis of the gyroscope reaches the set value, prepare to exit the ring; change the center offset E dif to adjust the center of the trolley's line following away from the ring, so as to achieve exiting the ring;

[0057] S523. Time for a period of time. When the inductance in the vertical direction decreases to the straight-line situation, assign 0 to the center offset E dif and the center of the line following returns to normal.

[0058] Based on the above technical solutions, the present invention has the following beneficial effects:

[0059] 1. Introducing the inductance in the vertical direction and integrating it with the inductance in the horizontal direction not only ensures the stability of the trolley on the straight section, but also improves its response speed and accuracy when turning at a right angle, enabling the trolley to promptly sense drastic changes in the environment and avoid steering delays;

[0060] 2. Design a PID controller with feedforward control and differential feedforward control; the feedforward control is used to estimate the expected output of the system to reduce the controller's dependence on errors, reduce the hysteresis effect, reduce the control errors caused by hysteresis, and thus improve the response speed; the differential feedforward control system can more quickly predict upcoming speed changes and make timely adjustments, reducing control errors under high-speed changes, enabling the trolley to cope with a more dynamic and changeable system environment. Description of the Drawings

[0061] Figure 1 This is the installation schematic diagram of the inductance sensor in the present invention;

[0062] Figure 2 This is the structural diagram of the PID controller involved in the present invention;

[0063] Figure 3 This is the flowchart of the method proposed by the present invention. Detailed implementation manners

[0064] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0065] Although the steps in the present invention are arranged with reference numerals, they are not used to limit the order of the steps. Unless the order of the steps is clearly stated or the execution of a certain step requires other steps as a basis, the relative order of the steps can be adjusted. It can be understood that the term "and / or" used herein relates to and encompasses any and all possible combinations of one or more of the associated listed items.

[0066] The method proposed by the present invention is implemented on the intelligent three-wheeled trolley system shown below; the specific hardware of this system includes:

[0067] Inductance detection device: An inductance bracket is arranged in front of the trolley, and two horizontal inductors and two vertical inductors are respectively placed on the inductance bracket. As Figure 1 shown, they are respectively used to detect electromagnetic signals in the horizontal and vertical directions. These sensors have the characteristics of high sensitivity and low noise, and can accurately capture the changes in the electromagnetic field;

[0068] Operational amplifier circuit: The weak signals output by the inductance sensor are amplified by a high-precision operational amplifier circuit to improve the signal-to-noise ratio of the signal and the accuracy of subsequent processing;

[0069] Microcontroller: As the core processing unit of the system, it is responsible for receiving the amplified inductance signals, executing signal processing algorithms, calculating the differential speed value, implementing PID control, and sending control instructions to the motor driver;

[0070] Gyroscope: Integrated on the trolley, it is used to detect the attitude and angular velocity changes of the trolley in real time, and provide auxiliary information for differential speed control and special element recognition;

[0071] Motor driver: Adjusts the output of the motor according to the instructions of the microcontroller, thereby controlling the driving speed and direction of the trolley.

[0072] A method for electromagnetic signal controlled car fixed - track cruise and special element recognition on the track proposed by the present invention is as follows Figure 3 as shown, and it specifically includes the following steps:

[0073] S1. Signal acquisition and processing: Collect inductance signals on the track through four inductance sensors, and pre - process them to obtain four inductance values; the inductance sensors are divided into a pair of horizontal inductance sensors and a pair of vertical inductance sensors.

[0074] As a preferred implementation, step S1 specifically includes:

[0075] S11. First, amplify the collected inductance signals through an operational amplifier circuit to improve the signal - to - noise ratio, and perform analog - to - digital conversion.

[0076] S12. Filter and denoise the converted digital inductance signals to obtain four pure inductance values, denoted as:

[0077] l ij ={l 11 ,l 12 ,l 21 ,l 22};

[0078] Among them, l 1j represents the horizontal inductance value, and l 2j represents the vertical inductance value.

[0079] S2. Error calculation: Perform fusion processing on the four inductance values obtained in step S1 to calculate the deviation value of the car's line following from the center line, and the deviation value is denoted as E; in this embodiment, the calculation formula for the deviation value is:

[0080]

[0081] S3. Differential speed control: According to the magnitude of the deviation value E, combined with the adjustable parameters of the car and the axis angular velocity feedback from the gyroscope, calculate the differential speed of the two wheels, control the steering of the car according to the differential speed of the two wheels to adapt to different turning angles, and obtain the actual control speeds of the left and right wheels of the car; the adjustable parameters include the car speed and load. In this embodiment, the speed is the set speed for the car to run smoothly in a straight line, and the load is the weight of the car, which is adjusted according to the feedback information of the PID controller during the actual experiment process.

[0082] As a preferred implementation, step S3 specifically includes:

[0083] S31. Set the maximum deviation value E max , when the deviation value E≥E max , automatically reduce the adjustment amount of the deviation, and reduce the speed of the motor through feedback adjustment to avoid severe oscillation and over - swing of the car.

[0084] S32. When E < E max , calculate the two-wheel differential value. The specific formula is:

[0085] S dif = P + D - ω feedback ;

[0086] P = K p *E;

[0087]

[0088] ω feedback = K g *ω;

[0089] Among them, S dif is the two-wheel differential, and P, D, and ω feedback are the proportional term, the derivative term, and the gyroscope feedback respectively; K p , K d , K g are the proportional term gain, the derivative term gain, and the gyroscope feedback gain respectively; ω is the angular velocity of the gyroscope feedback;

[0090] S33. According to the two-wheel differential value calculated in step S33, calculate the actual control speeds of the left and right wheels, that is, the target speeds of the left and right wheels. The specific formula is:

[0091]

[0092] Among them, S L , S R are the actual control speeds of the left and right wheels respectively; speed l , speed r are the initial speeds of the left and right wheels respectively.

[0093] S4. Input the obtained actual control speeds of the left and right wheels into the PID controller, and adjust the motor output through the PID controller to achieve real-time adjustment of the speeds of the left and right wheels; the PID controller is optimized by using an adaptive adjustment algorithm, and the control parameters are dynamically adjusted according to the actual driving state of the vehicle to achieve the best control effect;

[0094] As a preferred implementation, in step S4, the PID controller is optimized by adding an adaptive algorithm of feedforward control and differential feedforward control. The formula is expressed as:

[0095] Output = PID_val + Fwd_val;

[0096] PID_val = kP * Err + kI * Err sum + kD * D_Err;

[0097] Fwd_val = Ffwd(Target) + D_Fwd(Target);

[0098] Among them, Output is the control quantity finally output by the PID controller; Fwd_val is the feedforward control quantity; PID_val is the PID control quantity; kP, kI, and kD are the gains of the proportional P, integral I, and differential D parts of the PID controller respectively; Ffwd(v target ), D_Ffwd(v target ) are the outputs of the feedforward function and the differential feedforward function when the target speed is used as the input; v target is the target speed, that is, the actual control speed of the left and right wheels;

[0099] Taking the difference between the target speed and the actual speed as the input of the proportional P of the PID controller, and respectively performing accumulation and differential processing as the inputs of the integral I and the differential D, the formula is expressed as:

[0100] Err = v target - real;

[0101] Err sum = Err' sum + Err;

[0102] D_Err = Err - Err last ;

[0103] Among them, Err is the difference between the target speed v target and the encoder measurement speed v real at the current moment; Err sum is the accumulation of all differences up to the current moment, Err' sum is the accumulation of all differences up to the previous moment; D_Err is the difference between the difference Err at the current moment and the difference Err last at the previous moment; More specifically, the feedforward function and the differential feedforward function are specifically:

[0104] Feedforward function:

[0105] Ffwd(v) = K ff * v target ;

[0106] Among them, K ff is the gain of the feedforward function, and the output of the motor is pre-adjusted through the feedforward function to reduce the control error caused by the lag effect;

[0107] Differential feedforward function:

[0108]

[0109] Among them, K dff is the gain of the differential feedforward function; the differential feedforward function is used to adjust the change speed of the target speed in advance to control the output, so as to reduce the system response time

[0110] S5. When the trolley approaches the special elements on the track, the inductance signal detected by the inductance sensor changes. The microprocessor monitors it in real time and combines the gyroscope data to judge whether the trolley enters the special element area, and makes corresponding responses according to different elements; the special elements on the track include horizontal roadblocks and rings;

[0111] As a preferred embodiment, step S5 specifically includes:

[0112] S51. Detection and response to horizontal roadblocks; use the TOF module to detect the distance to the horizontal roadblock. When the distance reaches the steering set value, start turning left until the inductance information reaches the left-turn end condition, and then start turning right until the inductance information reaches the right-turn end condition to achieve bypassing the horizontal roadblock;

[0113] The left-turn end condition is: when the inductance signal cannot be detected, and the inductance value is weak and close to 0, it is also considered that the inductance signal cannot be detected;

[0114] The right-turn end condition is: when the inductance values of the middle two reach 50% of the maximum value;

[0115] S52. Detection and response to rings; judge that when all four inductance values reach the ring entry reference value, the deviation value E between the trolley's line following and the center line is affected by the center offset E dif to control the trolley to enter and pass through the ring; E dif The relationship formula with E is expressed as:

[0116] E = E' + E dif ;

[0117] Among them, E' represents the deviation value of the previous moment, and the center offset E dif carries real-time inductance information;

[0118] The specific process is as follows:

[0119] S521. By applying the center offset E dif , change the trolley's line following center. When the line following center approaches the ring, control the trolley to enter the ring;

[0120] S522. Use the gyroscope inside the ring. When the yaw axis angle of the gyroscope reaches the set value, prepare to exit the ring; change the center offset E dif , adjust the trolley's line following center away from the ring, so as to achieve exiting the ring;

[0121] S523, timing for a period of time, when the vertical inductance is reduced to the straight-ahead condition, the center offset E is given dif Assign a value of 0, and the patrol line center returns to the positive position;

[0122] It should be noted that, in the present embodiment, the vertical inductance value of the car is weak when it is traveling in a straight line, but at the intersection of the circular ring and the straight path, the inductance signal is strong, and the four inductance values in the vertical and horizontal directions are increased. When the four inductances are greater than 50% of the maximum value, it is considered that the circular ring has been reached. The reference value for entering the circular ring is reached; for specific steering, because the inductance value on one side will be greater than the other side, the offset is adjusted toward the side with a larger inductance value according to the relationship between the inductance values on the left and right sides. While within the circular ring, the movement of the car needs to be adjusted not only according to the horizontal deviation, but also according to the change in height (i.e., the vertical direction) for more precise adjustments. Adding a vertical inductance value can sense whether the car is too close to the edge of the circular ring, or whether the steering angle needs to be increased or decreased, thereby providing more precise path adjustment.

[0123] S6. Conduct experiments on the car according to steps S1-S5 and record its driving trajectory, speed change, and response time parameters, evaluate the positioning accuracy, response speed, and adaptability of the method; and optimize and adjust the car parameters based on the evaluation results; in this embodiment, specific evaluation indicators include: whether the car's movement posture is stable, whether it is thrown off the track when turning, whether the movement trajectory follows the line, and whether it can effectively identify and respond to special elements of the track.

[0124] In summary, the method proposed in the present invention can ensure the stability of the car in straight sections, and also improve its response speed and accuracy when making right-angle turns, so that the car can perceive drastic changes in the environment in time and avoid steering delays; designing a PID controller with feedforward control and differential feedforward control can reduce the control error caused by hysteresis and improve the response speed; it can also quickly predict speed changes and adjust them in time to reduce control errors under high-speed changes, so that the car can cope with a more dynamic and changeable system environment.

[0125] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numerals in the claims should not be regarded as limiting the claims involved.

[0126] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only includes an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for controlling a car to perform fixed-path cruising and identifying special elements on a track by electromagnetic signals, characterized in that, Specifically, it includes the following steps: S1. Signal acquisition and processing: Collect inductance signals on the track through four inductance sensors, and perform preprocessing to obtain four inductance values. The inductance sensors are divided into a pair of horizontal inductance sensors and a pair of vertical inductance sensors; S2. Error calculation; Perform fusion processing on the four inductance values obtained in step S1 to calculate the deviation value between the car's line following and the center line, and the deviation value is denoted as E; S3. Differential speed control: According to the magnitude of the deviation value E, combined with the adjustable parameters of the car and the axis angular velocity feedback by the gyroscope, calculate the differential speed of the two wheels. Control the car to turn according to the differential speed of the two wheels to adapt to different turning angles, and obtain the actual control speeds of the left and right wheels of the car. The adjustable parameters include the car speed and load; S4. Input the obtained actual control speeds of the left and right wheels into the PID controller, and adjust the motor output through the PID controller to achieve real-time adjustment of the speeds of the left and right wheels. The PID controller is optimized by using an adaptive adjustment algorithm, and the control parameters are dynamically adjusted according to the actual driving state of the car to achieve the best control effect; S5. When the car approaches a special element on the track, the inductance signal detected by the inductance sensor changes. The microprocessor monitors it in real time and combines the gyroscope data to judge whether the car enters the special element area, and makes corresponding responses according to different elements. The special elements on the track include horizontal roadblocks and rings; S6. Conduct experiments on the car according to steps S1 - S5 and record the parameters of its driving trajectory, speed change, and response time, evaluate the positioning accuracy, response speed, and adaptability of the method; and optimize and adjust the car parameters according to the evaluation results.

2. A method for electromagnetic signal controlled car fixed-track cruise and special track element recognition according to claim 1, characterized in that, The preprocessing in step S1 includes: S11. First, amplify the collected inductance signal through an operational amplifier circuit to improve the signal-to-noise ratio, and perform analog-to-digital conversion; S12. Filter and denoise the converted digital inductance signal to obtain four pure inductance values, denoted as: l ij ＝{l 11 ,l 12 ,l 21 ,l 22}； Among them, l 1j represents the inductance value in the horizontal direction, and l 2j represents the inductance value in the vertical direction.

3. A method for electromagnetic signal controlled car fixed - path cruise and special track element recognition according to claim 2, characterized in that, The specific calculation formula for the deviation value E in step S2 is:

4. A method for electromagnetic signal controlled car fixed-track cruise and special element recognition of the track, characterized in that Step S3 specifically includes: S31. Set the maximum deviation value E max , when the deviation value E ≥ E max , automatically reduce the adjustment amount of the deviation, and reduce the speed of the motor through feedback adjustment to avoid severe oscillation and overswing of the trolley; S32. When E < E max , calculate the two-wheel differential value. The specific formula is as follows: S dif = P + D - ω feedback ; P = K p *E; ω feedback = K g * ω; Among them, S dif is two-wheel differential, and P, D, ω feedback are the proportional term, the derivative term, and the gyroscope feedback respectively; K p , K d , K g are the proportional term gain, the derivative term gain, and the gyroscope feedback gain respectively; ω is the angular velocity of the gyroscope feedback; S33. According to the differential speed value of the two wheels calculated in step S33, calculate the actual control speeds of the left and right wheels, that is, the target speeds of the left and right wheels. The specific formula is: Among them, S L and S R are the actual control speeds of the left wheel and the right wheel respectively; speed l and speed r are the initial speeds of the left wheel and the right wheel respectively.

5. A method for electromagnetic signal controlled car fixed-path cruise and special track element recognition according to claim 1, characterized in that, In step S4, the PID controller is optimized by adding an adaptive algorithm of feedforward control and differential feedforward control, and the formula is expressed as: Output = PID_val + Fwd_val; PID_val = kP * Err + kI * Err sum + kD * D_Err; Fwd_val = Ffwd(Target) + D_Fwd(Target); Among them, Output is the control quantity finally output by the PID controller; Fwd_val is the feedforward control quantity; PID_val is the PID control quantity; kP, kI, and kD are the gains of the proportional P, integral I, and derivative D parts of the PID controller respectively; Ffwd(v target ), D_Ffwd(v target ) are the outputs of the feedforward function and the differential feedforward function when the target speed is taken as the input; v target is the target speed, that is, the actual control speed of the left and right wheels; Take the difference between the target speed and the actual speed as the input of the proportional P of the PID controller, and use cumulative sum and differential processing as the inputs of the integral I and the differential D respectively. The formula is expressed as: Err = v target -v real ; Err sum = Err' sum + Err; D_Err = Err - Err last ; where Err is the difference between the target speed v at the current moment target and the encoder-measured speed v real ; Err sum is the accumulation of all differences up to the current moment, and Err' sum is the accumulation of all differences up to the previous moment; D_Err is the difference between the difference Err at the current moment and the difference Err last at the previous moment.

6. A method for electromagnetic signal controlled car fixed-track cruising and special track element recognition according to claim 5, characterized in that, The feedforward function and the differential feedforward function are specifically: Feedforward function: Ffwd(v) = K ff *v target ; Among them, K ff is the gain of the feedforward function, which pre-adjusts the output of the motor through the feedforward function to reduce the control error caused by the hysteresis effect; Differential feedforward function: Among them, K dff is the gain of the differential feedforward function; the differential feedforward function is used to advance the adjustment and control output of the change speed of the target speed, so as to reduce the system response time.

7. A method for electromagnetic signal controlled car fixed-track cruise and special element recognition of the track, characterized in that, Step S5 specifically includes: S51. Horizontal roadblock detection and response: Use the TOF module to detect the distance to the horizontal roadblock. When the distance reaches the turning set value, start turning left until the inductance information reaches the left-turn end condition, and then start turning right until the inductance information reaches the right-turn end condition to achieve bypassing the horizontal roadblock; The left turn end condition is: when the inductance signal cannot be detected, and the inductance value is weak and close to 0, it is also considered that the inductance signal cannot be detected; The right turn end condition is: when the inductance values of the middle two reach 50% of the maximum value; S52. Ring Detection and Response; When it is determined that all four inductance values reach the ring entry reference value, the center offset E is used dif to affect the deviation value E between the car's line following and the center line, so as to control the car's entry into and passing through the ring; E dif The relational formula of E and E is expressed as: E = E' + E dif ; Among them, E' represents the deviation value at the previous moment, and the center offset E dif with real-time inductance information; The specific process is: S521. By applying a central offset E dif to change the center of the vehicle's line following, when the line following center approaches the ring, control the vehicle to enter the ring; S522. Use a gyroscope inside the loop. When the yaw axis angle of the gyroscope reaches the set value, prepare to exit the loop; change the center offset E dif , adjust the center of the car's line following away from the ring, so as to achieve exiting the loop; S523. Time for a period. When the inductance in the vertical direction decreases to the straight - running condition, assign a value of 0 to the center offset E, and the line - following center returns to normal. dif Assign a value of 0, and the line - following center returns to the correct position.

8. A method for electromagnetic signal controlled car fixed-track cruise and special track element recognition according to claim 7, characterized in that The central offset E in step S52 dif According to the inductance change, it is expressed by the formula as follows: E dif = f(V, H); where V represents the inductance value in the vertical direction, and H represents the inductance value in the horizontal direction.

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