CN109835416B

CN109835416B - Steering assisting method for automobile steering wheel

Info

Publication number: CN109835416B
Application number: CN201910173594.9A
Authority: CN
Inventors: 黄向东; 张博雅; 温帆; 唐之刚; 王少卿; 宁清曌
Original assignee: Xian University of Science and Technology
Current assignee: Xian University of Science and Technology
Priority date: 2019-03-07
Filing date: 2019-03-07
Publication date: 2021-03-19
Anticipated expiration: 2039-03-07
Also published as: CN109835416A

Abstract

The invention discloses an automobile steering wheel steering auxiliary method.A steering auxiliary system of an automobile steering wheel comprises an automobile steering wheel rotating angle measuring unit, an automobile tire rotating angle measuring unit and an automobile steering wheel steering auxiliary control unit, wherein the automobile steering wheel rotating angle measuring unit comprises a DSP processor module, a power circuit module, a first Zigbee wireless communication module, an angle measuring module, a key circuit module and a display module; the automobile tire rotation angle measuring unit comprises an ARM microcontroller, a second Zigbee wireless communication module and a magnetostrictive displacement sensor; the steering auxiliary control unit of the automobile steering wheel comprises a power-assisted steering motor. The automobile steering wheel steering auxiliary system is reasonable in design, can assist a driver to operate a steering wheel correctly by combining an auxiliary method, can effectively reduce traffic accidents caused by tire faults, is good in using effect and convenient to popularize and use.

Description

Steering assisting method for automobile steering wheel

Technical Field

The invention belongs to the technical field of automobile safety, and particularly relates to an automobile steering wheel steering assisting method.

Background

With the rapid development of economy in China, the rapid progress of automobile industry and the continuous improvement of living standard of people, the number of automobiles is gradually increased, all countries in the world have strict quality control on the qualification of drivers, and ordinary people can drive the automobiles only after getting a driver license, which not only guarantees the safety of the drivers, but also protects the public safety of society, and the driving students face a serious problem in the early learning stage: the current position of the steering wheel cannot be mastered, and partial drivers cannot master the current position of the steering wheel due to tension in the stage that the trainees just take the driving license to drive to get on the road under the conditions of large traffic flow and complex road conditions, so that huge potential safety hazards are caused, and the safety of the drivers and pedestrians is endangered.

The automobile steering wheel is a device for controlling the driving direction of an automobile by a driver, the steering wheel controls tires to change the driving direction of the automobile leftwards and rightwards through a steering mechanism or keeps the automobile to run straight, tire faults are most worried and difficult to prevent by all drivers during the high-speed running of the automobile, and are one of important reasons for sudden traffic accidents, the steering transmission ratio refers to the ratio of the steering degree of the steering wheel to the steering degree of wheels, a certain steering transmission ratio exists between the steering degree of the steering wheel and the steering degree of the wheels of each automobile, if the tires are in fault, the steering transmission ratio can be changed, the steering degree of the wheels is not consistent with the corresponding steering degree of the steering wheel, the driving path is deviated from the requirements of the driver, if the correction is not timely, serious traffic accidents can occur, particularly heavy trucks, therefore, an automobile steering wheel steering auxiliary system is urgently needed, and through calculation correction, appropriate driving voltage is provided for the power steering motor on the steering pull rod.

The power-assisted steering motor has high nonlinearity and time-varying property, and the conventional PID control is difficult to ensure that the power-assisted steering motor obtains good control effect under different working states; compared with the conventional PID control, the fuzzy PID control can reduce overshoot and improve response speed, and has better effect on time lag and uncertain objects, but once a rule base of the fuzzy PID controller is established, the rule base cannot be updated, the adaptability is lacked, and the precision of the whole control system is influenced; the artificial neural network has strong nonlinear approximation capability, self-learning capability and parallel processing capability, if fuzzy control, neural network control and traditional PID control can be combined, the defects that a traditional PID controller is not easy to set parameters on line in real time and the like can be overcome, then the weight of the PID neural network is optimized by using a bacterial foraging optimization algorithm, three parameters of the PID are adjusted on line, and a control method with excellent effect on a power-assisted steering motor is lacked in the prior art.

Disclosure of Invention

The technical problem to be solved by the invention is to provide an automobile steering wheel steering auxiliary system aiming at the defects in the prior art, which has the advantages of simple structure, reasonable design, convenient realization and low cost, can assist a driver to carry out correct steering wheel operation by a novice in combination with an auxiliary method, can effectively reduce traffic accidents caused by tire faults, has good use effect and is convenient to popularize and use.

In order to solve the technical problems, the invention adopts the technical scheme that: an automobile steering wheel steering auxiliary system comprises an automobile steering wheel rotation angle measuring unit, an automobile tire rotation angle measuring unit and an automobile steering wheel steering auxiliary control unit, wherein the automobile steering wheel rotation angle measuring unit comprises a shell and a circuit board, the shell is used for being installed in the middle of a steering wheel, the circuit board is arranged in the shell, a measuring circuit is integrated on the circuit board, the measuring circuit comprises a DSP processor module, a power circuit module and a first Zigbee wireless communication module, the power circuit module is used for supplying power to all power utilization modules in the measuring circuit, and the first Zigbee wireless communication module is connected with the DSP processor module; the input end of the DSP processor module is connected with an angle measuring module and a key circuit module, the output end of the DSP processor module is connected with a display module, the power circuit module comprises a lithium battery, a first voltage conversion circuit module which is connected with the output end of the lithium battery and is used for converting 3.7V voltage into 3.3V voltage, and a second voltage conversion circuit module which is connected with the output end of the lithium battery and is used for converting 3.7V voltage into 3.3V voltage and 1.9V voltage, the DSP processor module is connected with the output end of the second voltage conversion circuit module, and the angle measuring module, the key circuit module, the display module and the first Zigbee wireless communication module are all connected with the first voltage conversion circuit module; the automobile tire rotation angle measuring unit comprises an ARM microcontroller and a second Zigbee wireless communication module which is connected with the ARM microcontroller and is used for being wirelessly connected with and communicating with the first Zigbee wireless communication module, and the input end of the ARM microcontroller is connected with a magnetostrictive displacement sensor which is arranged on a steering pull rod of an automobile steering wheel; the automobile steering wheel steering auxiliary control unit comprises a power-assisted steering motor arranged on a steering pull rod of the automobile steering wheel, and the power-assisted steering motor is connected with the output end of the ARM microcontroller through a motor driving module.

The automobile steering wheel steering auxiliary system is characterized in that the shell is cylindrical, a plurality of open holes used for exposing the key circuit module and the display module are formed in the upper surface of the shell, and a miniUSB interface hole used for charging a lithium battery is formed in the side surface of the shell.

In the steering assist system for the steering wheel of the vehicle, the first voltage conversion circuit module comprises a 3.3V linear voltage regulator Q2, a non-polar capacitor C10, a non-polar capacitor C11, a non-polar capacitor C12, a light emitting diode D1 and a resistor R21, the No. 1 pin and the No. 3 pin of the linear voltage stabilizer Q2 and one end of the nonpolar capacitor C11 are all connected with the 3.7V voltage output end of the lithium battery, the 2 nd pin of the linear voltage regulator Q2 and the other end of the non-polar capacitor C11 are both grounded, the 5 th pin of the linear voltage regulator Q2 is the 3.3V output terminal of the first voltage conversion circuit module, and one end of the nonpolar capacitor C10, one end of the nonpolar capacitor C12 and one end of the resistor R21 are all connected, the other end of the resistor R21 is connected with the anode of the light-emitting diode D1, and the other end of the nonpolar capacitor C10, the other end of the nonpolar capacitor C12 and the cathode of the light-emitting diode D1 are all grounded; the second voltage conversion circuit module comprises a voltage regulator TPS767D301, a polar capacitor CT1, a polar capacitor CT2, a polar capacitor CT3, a polar capacitor CT4, a non-polar capacitor C7, a non-polar capacitor C8, a non-polar capacitor C9, a non-polar capacitor C13, a non-polar capacitor C14, a non-polar capacitor C15, a non-polar capacitor C16, an inductor L1, an inductor L2, a resistor R16 and a resistor R17, the 5 th pin, the 6 th pin, the 11 th pin, the 12 th pin, the positive electrode of the polar capacitor CT1, one end of the non-polar capacitor C13 and one end of the non-polar capacitor C14 of the voltage regulator TPS767D301 are all connected with a 3.7V voltage output terminal of a lithium battery, the 3 rd pin, the 4 th pin, the 9 th pin, the 10 th pin, the 29 th pin, the negative electrode of the polar capacitor CT1, the other end of the non-polar capacitor C13 and the other end of the non-polar capacitor C14 of the voltage regulator TPS 767V voltage conversion circuit module is a second voltage conversion circuit module TPS 761, and is connected to the 24 th pin of the voltage regulator TPS767D301, one end of the resistor R16, the positive electrode of the polar capacitor CT2, one end of the non-polar capacitor C7, and one end of the inductor L1, the 25 th pin of the voltage regulator TPS767D301 and the other end of the resistor R16 are connected to one end of the resistor R17, the negative electrode of the polar capacitor CT2, the other end of the non-polar capacitor C7, and the other end of the resistor R17 are grounded, the other end of the inductor L1 is grounded through the non-polar capacitor C15, the 17 th pin of the voltage regulator TPS767D301 is the 3.3V voltage output end of the second voltage conversion circuit module, and is connected to the 18 th pin of the voltage regulator TPS767D301, the positive electrode of the polar capacitor CT3, one end of the non-polar capacitor C8, the positive electrode of the polar capacitor CT4, one end of the non-polar capacitor C48, and one end of the TPS L2, the first pin of the voltage regulator TPS767D301, the negative electrode of the polar capacitor CT 7619, the polar capacitor CT, The negative electrode of the polar capacitor CT4 and the other end of the nonpolar capacitor C9 are both grounded, and the other end of the inductor L2 is grounded through the nonpolar capacitor C16.

The automobile steering wheel steering auxiliary system comprises a DSP chip TMS320F2812, a crystal oscillator Y1, a nonpolar capacitor CX1 and a nonpolar capacitor CX2, and a reset circuit connected with the DSP chip TMS320F2812, wherein one end of the crystal oscillator Y1 and one end of the nonpolar capacitor CX1 are connected with a 77 th pin of the DSP chip TMS320F2812, the other end of the crystal oscillator Y1 and one end of the nonpolar capacitor CX2 are connected with a 76 th pin of the DSP chip TMS320F2812, the other end of the nonpolar capacitor CX1 and the other end of the nonpolar capacitor CX2 are all grounded, a 31 th pin, a 64 th pin, a 69 th pin, a 81 th pin, a 114 th pin and a 145 th pin of the DSP chip TMS320F2812 are all connected with a 3.3V voltage output end of a second voltage conversion circuit module, and a 23 th pin, a 37 th pin, a 56 th pin, a 75 th pin, a 128 th pin, a pin 112, a 128 th pin 112 and a 23 th pin of the DSP chip TMS320F2812 are connected with the DSP chip TMS, The 143 th pin and the 154 th pin are both connected with a 1.9V voltage output end of the second voltage conversion circuit module, and the 19 th pin, the 32 nd pin, the 38 th pin, the 52 th pin, the 58 th pin, the 70 th pin, the 78 th pin, the 86 th pin, the 99 th pin, the 105 th pin, the 113 th pin, the 120 th pin, the 129 th pin, the 142 th pin and the 153 th pin of the DSP chip TMS320F2812 are all grounded; the reset circuit comprises a processor monitor chip MAX690_ ESA, a switch diode DT1, a non-polar capacitor CX3, a non-polar capacitor CX4, a resistor RX8 and a resistor RX9, wherein one end of the No. 1 pin, the No. 2 pin, the No. 8 pin and the non-polar capacitor CX3 of the processor monitor chip MAX690_ ESA are connected with the 3.3V voltage output end of the second voltage conversion circuit module, the No. 3 pin, the No. 4 pin and the other end of the non-polar capacitor CX3 of the processor monitor chip MAX690_ ESA are grounded, the No. 6 pin of the processor monitor chip 690_ ESA is connected with the 131 rd pin of the DSP chip TMS320F2812 and is connected with the 3.3V voltage output end of the second voltage conversion circuit module through the resistor RX9, the No. 7 pin of the processor monitor chip 690_ ESA, the anode of the switch diode DT1, one end of the resistor RX8 and one end of the non-polar capacitor CX4 are connected with the No. 135 pin of the DSP chip CX 281320F 2 of, the cathode of the switching diode DT1 and the other end of the resistor RX8 are both connected to the 3.3V voltage output terminal of the second voltage conversion circuit module, and the other end of the non-polar capacitor CX4 is grounded.

The steering auxiliary system for the automobile steering wheel comprises a three-dimensional angle sensor MPU-6050, a nonpolar capacitor C17, a nonpolar capacitor C18, a nonpolar capacitor C19, a resistor R18 and a resistor R19, wherein one end of the 8 th pin, the 13 th pin and the nonpolar capacitor C17 of the three-dimensional angle sensor MPU-6050 are connected with the 3.3V voltage output end of a first voltage conversion circuit module, the other end of the 1 st pin, the 11 th pin, the 18 th pin and the nonpolar capacitor C17 of the three-dimensional angle sensor MPU-6050 are grounded, the 10 th pin of the three-dimensional angle sensor MPU-6050 is grounded through a nonpolar capacitor C18, the 20 th pin of the three-dimensional angle sensor MPU-6050 is grounded through a nonpolar capacitor C19, the 23 th pin of the three-dimensional angle sensor MPU-6050 is connected with the 3.3V voltage output end of the first voltage conversion circuit module through a resistor R19, and the 24 th pin of the three-dimensional angle sensor MPU-6050 is connected with the 3.3V voltage output end of the first voltage conversion circuit module through a resistor R18 and is connected with the 157 th pin of the DSP chip TMS320F2812, and the 6 th pin, the 7 th pin, the 9 th pin and the 12 th pin of the three-dimensional angle sensor MPU-6050 are sequentially connected with the 155 th pin, the 34 th pin, the 127 th pin and the 79 th pin of the DSP chip TMS320F2812 correspondingly.

The steering assist system for the steering wheel of the automobile comprises a key S1, a key S2, a resistor R23 and a resistor R24, wherein one end of the key S1 is connected with a 3.3V voltage output end of a first voltage conversion circuit module through a resistor R23 and is connected with an 18 th pin of a DSP chip TMS320F2812, one end of the key S2 is connected with a 3.3V voltage output end of the first voltage conversion circuit module through a resistor R24 and is connected with a 43 th pin of the DSP chip TMS320F2812, and the other end of the key S1 and the other end of the key S2 are both grounded.

The display module comprises a TFT display screen U5, a 31 st pin of the TFT display screen U5 is connected to a 3.3V voltage output end of the first voltage conversion circuit module, a1 st pin and a 32 nd pin of the TFT display screen U5 are both grounded, and a2 nd pin, a3 rd pin, a4 th pin, a5 th pin, a6 th pin, a 7 th pin, an 8 th pin, a 9 th pin, a 10 th pin, an 11 th pin, a 12 th pin, a 13 th pin, a 14 th pin, a 15 th pin, a 16 th pin, a 17 th pin, an 18 th pin, a 19 th pin, a 20 th pin, a 21 st pin, a 22 th pin, a 23 th pin, a 24 th pin, a 25 th pin, a 26 th pin, a 27 th pin and a 28 th pin of the TFT display screen U5 are sequentially corresponding to a 66 th pin, a 147 th pin, a 139 th pin, a 97 th pin, a TMS pin, a 20 th pin, a 15 th pin of a DSP chip 281320F 2, The 96 th pin, the 74 th pin, the 73 th pin, the 68 th pin, the 65 th pin, the 54 th pin, the 39 th pin, the 36 th pin, the 33 th pin, the 30 th pin, the 27 th pin, the 24 th pin, the 21 st pin, the 42 th pin, the 51 st pin, the 160 th pin, the 44 th pin, the 136 th pin, the 88 th pin, the 123 th pin, the 122 th pin, the 110 th pin and the 92 th pin.

The first Zigbee wireless communication module comprises a Zigbee wireless communication module U6 with the model number CC2530, a VCC pin of the Zigbee wireless communication module U6 is connected with a 3.3V voltage output end of the first voltage conversion circuit module, a GND pin of the Zigbee wireless communication module U6 is grounded, a TX pin of the Zigbee wireless communication module U6 is connected with a 91 th pin of the DSP chip TMS320F2812, and an RX pin of the Zigbee wireless communication module U6 is connected with a 90 th pin of the DSP chip TMS320F 2812.

The invention also discloses an automobile steering wheel steering auxiliary method, which comprises a steering wheel rotating angle identification method for assisting a driver to correctly identify the steering wheel rotating angle and a method for assisting the driver to control the steering wheel by controlling the power-assisted steering motor by the ARM microcontroller when the steering transmission ratio of the steering wheel is abnormally changed;

the steering wheel rotation angle identification method comprises the following steps:

a1, when the automobile steering wheel and the automobile tire are not in fault, the automobile steering wheel is placed at an initial position, namely a 0-degree position;

step A2, pasting the back of the shell of the automobile steering wheel rotation angle measuring unit at the middle position of the automobile steering wheel;

step A3, rotating the automobile steering wheel to the left, pressing a key S1 in the key circuit module once when the automobile steering wheel rotates 45 degrees, detecting the current angle information by the angle measuring module, and transmitting the current angle information to the DSP processor module for recording and storing until the automobile steering wheel rotates to the left limit;

step A4, turning the steering wheel of the automobile back to the initial position;

step A5, rotating the automobile steering wheel to the right, pressing a key S2 in the key circuit module once when the automobile steering wheel rotates 45 degrees, detecting the current angle information by the angle measuring module, and transmitting the current angle information to the DSP processor module for recording and storing until the automobile steering wheel rotates to the right limit;

step A6, after the automobile is started, detecting the rotation angle of the automobile steering wheel in real time by an angle measurement module, when a driver turns the steering wheel to the left, displaying a left arrow and a rotation angle by a display module, and when the driver needs to turn the steering wheel to the right, still lighting the left arrow to prompt that the current steering wheel is still in a left angle area, and simultaneously flashing the right arrow to prompt that the current steering wheel is turned to the right until the steering wheel is turned to the initial position, and turning off both the left arrow and the right arrow; when a driver turns a steering wheel to the right, the display module displays a rightward arrow and simultaneously displays a rotation angle, when the driver needs to turn the steering wheel to the left, the rightward arrow is still lightened to prompt that the current steering wheel is still in a right angle area, and meanwhile, the leftward arrow can be lightened to prompt that the current steering wheel is rotated to the left until the steering wheel is turned back to an initial position, and the leftward arrow and the rightward arrow are both extinguished;

the ARM microcontroller controls the power-assisted steering motor, and the method for assisting a driver in steering wheel control comprises the following steps:

step B1, when the automobile steering wheel rotates, the magnetostrictive displacement sensor arranged on the steering pull rod of the automobile steering wheel detects the translation distance value of the steering pull rod, and the ARM microcontroller collects the detected translation distance value; detecting a rotation angle value e of a steering wheel of a vehicle by an angle measuring module in a steering wheel rotation angle measuring unit of a vehicle mounted on the steering wheel of the vehicle₁And the detected steering wheel rotation angle value e is detected through a first Zigbee wireless communication module and a second Zigbee wireless communication module which are in wireless connection and communication₁Transmitting the data to an ARM microcontroller;

step B2, the ARM microcontroller obtains the rotation angle of the automobile tire from the stored data according to the preset corresponding data of the translation distance of the steering rod and the rotation angle of the automobile tire, and the specific process is as follows:

step B201, in the rotation range of the automobile tire, counting the translation distance of the steering pull rod corresponding to each change of 1 degree of the rotation angle of the inner side of the tire from the left limit to the right limit;

step B202, storing corresponding data of the translation distances of the multiple groups of steering pull rods and the rotation angles of the automobile tires into an ARM microcontroller;

step B203, when the magnetostrictive displacement sensor detects the translation distance value of the steering pull rod, the ARM microcontroller acquires the rotation angle of the automobile tire from the stored data;

step B3, the ARM microcontroller calculates the rotation angle value e of the automobile steering wheel according to the steering transmission ratio between the steering degree of the automobile steering wheel and the steering degree of the tire₂；

Step B4, the ARM microcontroller detects the direction according to the rotation angle of the steering wheelAngle value e of rotation to the dial₁And the steering wheel rotation angle value e calculated by the automobile tire rotation angle measuring unit₂The method is characterized in that optimized fuzzy neural network PID control is implemented on a power-assisted steering motor on a steering pull rod, and the specific process is as follows:

step B401, the ARM microcontroller calculates e₁And e₂E is equal to e₁-e₂(ii) a Calculating the difference change rate ec ═ e₁-e₂)/e₁；

Step B402, taking e and ec as two nodes of an input layer in the fuzzy neural network;

b403, dividing e and ec into fuzzy subsets, determining the number of nodes of a fuzzy layer in the fuzzy neural network, wherein the membership function adopts a Gaussian function;

b404, determining the number of nodes of a fuzzy rule layer in the fuzzy neural network;

b405, resolving the ambiguity of the de-ambiguity layer in the ambiguity neural network by adopting a gravity center method to form a node which is used as a node of a PID input layer in the PID neural network;

step B406, adding K_P、K_I、K_DAs three nodes of a PID layer in the PID neural network, the weight of the PID neural network is optimized by adopting an improved bacterial foraging optimization algorithm, so that the K of a static parameter_P、K_I、K_DConverting into a dynamic adjustment form;

step B407, outputting the control voltage U optimized to the power-assisted steering motor by an output layer in the PID neural network^*。

The specific process of optimizing the weight of the PID neural network by using the improved bacterial foraging optimization algorithm in the step B406 of the method is as follows:

step B4061, initializing bacterial foraging optimization algorithm parameters: the bacterial foraging optimization algorithm parameters comprise a search working dimension p of a total bacterial count S, PID control parameter corresponding to a PID control parameter in a bacterial flora and chemotaxis times N of the PID control parameter_cMaximum step number N of one-way movement of PID control parameter in chemotaxis process_SNumber of copies of PID control parameterNumber N_reAnd learning frequency N of PID control parameter_edMaximum chemotaxis step length C of PID control parameter_maxAnd minimum chemotaxis step size C of PID control parameter_min；

Step B4062, initializing the flora location: by means of random initialization and according to the formula X ═ X_min+rand×(X_max-X_min) Initializing 2S points in p-dimensional space as initialization positions of bacteria, wherein S bacteria are randomly selected as flora X₁The remaining S bacteria are used as flora X₂；X_minFor minimum value of the optimization interval, X_maxFor the maximum value of the optimization interval, X is the initialization position of the bacteria, and rand is uniformly distributed in [0,1 ]]A random number of intervals;

step B4063, updating the fitness value: according to the formula

Calculating the fitness value of each bacterium; wherein d is_attractDepth of attraction between bacteria, w_attractWidth of attraction between bacteria, h_repellentHeight of repulsion between bacteria, w_repellentThe width of the repulsion between bacteria, P (i, J, k, l) is the position of the bacteria i after the jth tropism operation, the kth replication operation and the ith migration operation, P (1: S, J, k, l) is a random position in the neighborhood of the current individual P (i, J, k, l), J (1: S, J, k, l)_CC(i, j, k, l) is the fitness value of the bacterium i after the jth tropism operation, the kth replication operation and the l migration operation;

step B4064, setting parameters of circulation variables: wherein the chemotaxis cycle number j is 1 to N_cThe number of reproduction cycles k is 1 to N_reLearning cycle times l is 1-N_ed；

Step B4065, entering into chemotaxis circulation to perform chemotaxis operation, wherein the specific method comprises the following steps:

against bacterial flora X₂Chemotaxis of each bacterium was performed according to the following chemotaxis operation of step Q21 to step Q211:

step Q21, reassigning the bacteria i to i +1, judging whether the scale of the bacteria i is smaller than the total number S of the bacteria, executing a step Q22 when the scale of the bacteria i is smaller than the total number S of the bacteria, and executing a step Q212 when the scale of the bacteria i is not smaller than the total number S of the bacteria;

step Q22, calculating the fitness value of the bacterium i;

step Q23, bacteria i are turned one unit step in the randomly generated direction;

step Q24, initializing j to 1;

step Q25, calculating the fitness value of the bacteria i at the new position;

step Q26, judge if j is less than the maximum step number N_SWhen less than, executing the step Q27, and when not less than, jumping to execute the step Q21;

step Q27, reassigning j to j + 1;

step Q28, determining whether the fitness value of bacterium i at the new position has changed, and if so, executing step Q29, and if not, making j equal to N_SAnd jumps to execute step Q26;

step Q29, updating the fitness value of the bacterium i;

step Q210, the bacterial population continues to swim in the overturning direction;

step Q211, jumping to execute step Q25, and continuing to circulate until the value of i in step Q21 is equal to S;

step Q212, the chemotaxis operation is finished;

against bacterial flora X₁Chemotaxis of each bacterium was performed according to the following chemotaxis operation of step Q11 to step Q112:

step Q11, reassigning the bacteria i to i +1, judging whether the scale of the bacteria i is smaller than the total number S of the bacteria, executing a step Q12 when the scale of the bacteria i is smaller than the total number S of the bacteria, and executing a step Q112 when the scale of the bacteria i is not smaller than the total number S of the bacteria;

step Q12, calculating the fitness value of the bacterium i;

step Q13, according to the formula

Calculating a bacterial flora density function factor D (i), and calculating a chemotaxis step length C (i) according to a formula C (i) ═ A.D (i) + B; then turning bacterium i by step length C (i) in the direction of random generation; wherein L isMaximum length in diagonal line of search space, X (m, i) is position coordinate value of bacterium i in m-th dimension of search space, X is average position coordinate value of all bacteria in m-th dimension of search space in current search space;

step Q14, initializing j to 1;

step Q15, calculating the fitness value of the bacteria i at the new position;

step Q16, judge if j is less than the maximum step number N_SWhen less than, executing the step Q17, and when not less than, jumping to execute the step Q11;

step Q17, reassigning j to j + 1;

step Q18, determining whether the fitness value of bacterium i at the new position has changed, and if so, executing step Q19, and if not, making j equal to N_SAnd jumps to execute step Q16;

step Q19, updating the fitness value of the bacterium i;

step Q110, the bacterial population continues to swim in the overturning direction;

step Q111, jumping to execute step Q15, and continuing to circulate until the value of i in step Q11 is equal to S;

step Q112, the chemotaxis operation is finished;

step B4066, entering a replication cycle, and performing replication operation, wherein the method specifically comprises the following steps:

against bacterial flora X₁Each bacterium was replicated according to the following replication operations of step F11 to step F16:

step F11, reassigning the bacteria i to i +1, judging whether the scale of the bacteria i is smaller than the total number S of the bacteria, executing step F12 when the scale of the bacteria i is smaller than the total number S of the bacteria, and executing step F16 when the scale of the bacteria i is not smaller than the total number S of the bacteria;

step F12, calculating the sum of the fitness of all positions passed by the bacteria in the last replication operation cycle, and defining the sum as a health value;

step F13, sequencing the bacteria according to the quality of the health value;

f14, jumping to execute the step F11;

step F15, eliminating the poor health

Bacteria, the rest

Each bacterium divides a new individual which is completely the same as the bacterium itself;

step F16, the copying operation is finished;

against bacterial flora X₂Each bacterium was replicated according to the following replication operations of step F21 to step F24:

step F21, calculating the fitness values of all bacteria, sequencing the bacteria in a sequence from small to large, and selecting the currently optimal bacteria as elite bacteria;

step F22, carrying out treatment on the currently best half of bacteria according to the formula X'₂(i)＝X₂(i) + N (0,1) is mutated to generate

The new bacteria and the original bacteria form a new daughter bacterial flora X'₂(ii) a Wherein N (0,1) is a Gaussian distribution with a mean value of 0 and a mean square error of 1;

step F23, performing cross operation on the worst half of the bacteria according to golden section ratio and the bacteria sorted in the first 61.8 percent and the elite bacteria selected in the step F21 to generate

The new bacteria and the original bacteria form a new daughter bacterial group X₂；

Step F24, obtaining from daughter bacterial flora X'₂Fungus group X₂Selecting the first S bacteria with the best fitness value to replace the original bacteria group X₂；

Step B4067, entering a learning cycle to perform learning operation, wherein the specific method comprises the following steps: bacterial group X₁With the bacterium group X₂The bacteria in (1) are sequenced, and the flora X is₁The first 61.8% of the bacteria were selected to be 0.382S bacteria and group X according to roulette' S method₂In the middle rank ofThe last 38.2% of the bacteria were exchanged, and the exchanged 0.382S bacteria constituted a new bacterial group X₂；

And step B4068, judging whether the cycle frequency of the chemotaxis cycle, the replication cycle and the learning cycle reaches a set value, when the cycle frequency reaches the set value, finishing the cycle, comparing the optimal bacteria found in the two floras through a fitness value, selecting the best bacteria as a global optimal solution, and outputting the result, otherwise, continuously and circularly executing the steps B4065-B4068 until the cycle frequency of the chemotaxis cycle, the replication cycle and the learning cycle reaches the set value.

Compared with the prior art, the invention has the following advantages:

1. the steering auxiliary system of the automobile steering wheel has the advantages of simple structure, reasonable design, convenient realization and low cost, and the rotation angle measuring unit of the automobile steering wheel only needs to be installed on the existing automobile steering wheel.

2. The automobile steering wheel rotation angle measuring unit provided by the invention can be used for visually displaying the rotation direction and the rotation angle of the steering wheel on the display module by combining the angle measuring module with the DSP processor module, so as to assist a driver to carry out correct operation and avoid accidents caused by wrong steering wheel hitting due to overstrain.

3. The automobile steering wheel steering auxiliary system combining method can timely find the steering rotation ratio change caused by tire faults, correct the steering transmission ratio through the optimized fuzzy neural network PID control of the power-assisted steering motor, effectively reduce traffic accidents caused by tire faults, have good use effect and are convenient to popularize and use.

In conclusion, the steering auxiliary system for the automobile steering wheel has the advantages of simple structure, reasonable design, convenience in realization and low cost, can assist a driver to perform correct steering wheel operation by combining an auxiliary method, can effectively reduce traffic accidents caused by tire faults, is good in using effect, and is convenient to popularize and use.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

FIG. 1 is a schematic block diagram of the circuit of the present invention;

FIG. 2 is a schematic structural diagram of a housing in the steering wheel rotation angle measuring unit of the present invention;

FIG. 3 is a schematic circuit diagram of a first voltage conversion circuit module according to the present invention;

FIG. 4 is a schematic circuit diagram of a second voltage conversion circuit module according to the present invention;

FIG. 5 is a schematic circuit diagram of a DSP processor module according to the present invention;

FIG. 6 is a circuit schematic of the reset circuit of the present invention;

FIG. 7 is a schematic circuit diagram of an angle measurement module of the present invention;

FIG. 8 is a schematic circuit diagram of a key circuit module according to the present invention;

FIG. 9 is a schematic circuit diagram of a display module according to the present invention;

fig. 10 is a schematic circuit diagram of a first Zigbee wireless communication module according to the present invention;

FIG. 11 is a diagram of the topology structure of the fuzzy neural network PID control of the present invention;

FIG. 12 is a graph comparing the effectiveness of the method of the present invention with fuzzy PID control, and fuzzy neural PID control.

Description of reference numerals:

1-a housing; 2-a DSP processor module; 3-power supply circuit module;

3-1-a lithium battery; 3-2-a first voltage conversion circuit module;

3-a second voltage conversion circuit module; 4-an angle measuring module;

5-a key circuit module; 6-a display module;

7-a first Zigbee wireless communication module; 8-ARM microcontroller;

9-a second Zigbee wireless communication module; 10-a magnetostrictive displacement sensor;

11-power steering motor; and 12, a motor driving module.

Detailed Description

As shown in fig. 1, the steering assist system for an automobile steering wheel of the present invention includes an automobile steering wheel rotation angle measuring unit, an automobile tire rotation angle measuring unit, and an automobile steering wheel steering assist control unit, and with reference to fig. 2, the automobile steering wheel rotation angle measuring unit includes a housing 1 for being mounted at a middle position of a steering wheel and a circuit board disposed in the housing 1, the circuit board is integrated with a measuring circuit, the measuring circuit includes a DSP processor module 2, a power circuit module 3 for supplying power to each power module in the measuring circuit, and a first Zigbee wireless communication module 7 connected to the DSP processor module 2; the input end of the DSP processor module 2 is connected with an angle measuring module 4 and a key circuit module 5, the output end of the DSP processor module 2 is connected with a display module 6, the power circuit module 3 comprises a lithium battery 3-1 and a first voltage conversion circuit module 3-2 which is connected with the output end of the lithium battery 3-1 and is used for converting 3.7V voltage into 3.3V voltage, and a second voltage conversion circuit module 3-3 connected to an output terminal of the lithium battery 3-1 for converting a voltage of 3.7V into voltages of 3.3V and 1.9V, the DSP processor module 2 is connected with the output end of the second voltage conversion circuit module 3-3, the angle measuring module 4, the key circuit module 5, the display module 6 and the first Zigbee wireless communication module 7 are all connected with the first voltage conversion circuit module 3-2; the automobile tire rotation angle measuring unit comprises an ARM microcontroller 8 and a second Zigbee wireless communication module 9 which is connected with the ARM microcontroller 8 and is used for being in wireless connection and communication with the first Zigbee wireless communication module 7, wherein the input end of the ARM microcontroller 8 is connected with a magnetostrictive displacement sensor 10 which is arranged on a steering pull rod of an automobile steering wheel; the automobile steering wheel steering auxiliary control unit comprises a power-assisted steering motor 11 installed on a steering pull rod of the automobile steering wheel, and the power-assisted steering motor 11 is connected with the output end of the ARM microcontroller 8 through a motor driving module 12.

In this embodiment, as shown in fig. 2, the housing 1 is cylindrical, the upper surface of the housing 1 is provided with a plurality of openings for exposing the key circuit module 5 and the display module 6, and the side surface of the housing 1 is provided with a miniUSB interface hole for charging the lithium battery 3-1.

In this embodiment, as shown in fig. 3, the first voltage conversion circuit module 3-2 includes a 3.3V linear regulator Q2, a non-polar capacitor C10, a non-polar capacitor C11, a non-polar capacitor C12, a light emitting diode D1 and a resistor R21, the No. 1 pin and the No. 3 pin of the linear voltage stabilizer Q2 and one end of the nonpolar capacitor C11 are connected with the 3.7V voltage output end of the lithium battery 3-1, the 2 nd pin of the linear voltage regulator Q2 and the other end of the non-polar capacitor C11 are both grounded, the 5 th pin of the linear voltage regulator Q2 is the 3.3V output terminal of the first voltage conversion circuit module 3-2, and one end of the nonpolar capacitor C10, one end of the nonpolar capacitor C12 and one end of the resistor R21 are all connected, the other end of the resistor R21 is connected with the anode of the light-emitting diode D1, and the other end of the nonpolar capacitor C10, the other end of the nonpolar capacitor C12 and the cathode of the light-emitting diode D1 are all grounded; as shown in fig. 4, the second voltage conversion circuit module 3-3 includes a voltage regulator TPS767D301, a polar capacitor CT1, a polar capacitor CT2, a polar capacitor CT3, a polar capacitor CT4, a non-polar capacitor C7, a non-polar capacitor C8, a non-polar capacitor C9, a non-polar capacitor C13, a non-polar capacitor C14, a non-polar capacitor C15, a non-polar capacitor C16, an inductor L1, an inductor L2, a resistor R16 and a resistor R17, the 5 th pin, the 6 th pin, the 11 th pin, the 12 th pin of the voltage regulator TPS767D301, the positive electrode of the polar capacitor CT1, one end of the non-polar capacitor C13 and one end of the non-polar capacitor C84 are all connected to the 3.7V voltage output terminal of the lithium battery 3-1, the 3 rd pin, the 4 th pin, the 9 th pin, the 10 th pin, the 29 th pin, the negative electrode of the polar capacitor CT 3742, the other end of the non-polar capacitor C4642 and the polar capacitor C14, a 23 th pin of the voltage regulator TPS767D301 is a 1.9V voltage output end of the second voltage conversion circuit module 3-3, and is connected to a 24 th pin of the voltage regulator TPS767D301, one end of the resistor R16, a positive electrode of the polar capacitor CT2, one end of the non-polar capacitor C7, and one end of the inductor L1, a 25 th pin of the voltage regulator TPS767D301 and the other end of the resistor R16 are connected to one end of the resistor R17, a negative electrode of the polar capacitor CT2, the other end of the non-polar capacitor C7, and the other end of the resistor R17 are all grounded, the other end of the inductor L1 is grounded through the non-polar capacitor C15, a 17 th pin of the voltage regulator TPS767D301 is a 3.3V voltage output end of the second voltage conversion circuit module 3-3, and is connected to a 18 th pin of the voltage regulator TPS 76tps 7D301, one end of the positive electrode of the polar capacitor 3, one end of the non-polar capacitor C638284, one end of the non-polar capacitor CT 8536, and one end of the inductor L89, the 19 th pin of the voltage regulator TPS767D301, the negative electrode of the polar capacitor CT3, the other end of the non-polar capacitor C8, the negative electrode of the polar capacitor CT4, and the other end of the non-polar capacitor C9 are all grounded, and the other end of the inductor L2 is grounded through the non-polar capacitor C16.

In this embodiment, as shown in fig. 5, the DSP processor module 2 includes a DSP chip TMS320F2812, a crystal oscillator Y1, a non-polar capacitor CX1, a non-polar capacitor CX2, and a reset circuit connected to the DSP chip TMS320F2812, one end of the crystal oscillator Y1 and one end of the non-polar capacitor CX1 are both connected to a 77 th pin of the DSP chip TMS320F2812, the other end of the crystal oscillator Y1 and one end of the non-polar capacitor CX2 are both connected to a 76 th pin of the DSP chip TMS320F2812, the other end of the non-polar capacitor CX1 and the other end of the non-polar capacitor CX2 are both grounded, a 31 th pin, a 64 th pin, a 69 th pin, an 81 th pin, a 114 th pin, and a 145 th pin of the DSP chip TMS320F2812 are all connected to a 3.3V voltage output terminal of the second voltage conversion circuit module 3-3, and a 23 rd pin, a 37 th pin, a 56 th pin, a 100 th pin, a 128 th pin, a pin 112, a, The 143 th pin and the 154 th pin are both connected with a 1.9V voltage output end of the second voltage conversion circuit module 3-3, and the 19 th pin, the 32 th pin, the 38 th pin, the 52 th pin, the 58 th pin, the 70 th pin, the 78 th pin, the 86 th pin, the 99 th pin, the 105 th pin, the 113 th pin, the 120 th pin, the 129 th pin, the 142 th pin and the 153 th pin of the DSP chip TMS320F2812 are all grounded; as shown in fig. 6, the reset circuit includes a processor monitor chip MAX690_ ESA, a switching diode DT1, a non-polar capacitor CX3, a non-polar capacitor CX4, a resistor RX8, and a resistor RX9, wherein one end of the 1 st pin, the 2 nd pin, the 8 th pin, and the non-polar capacitor CX3 of the processor monitor chip MAX690_ ESA are connected to the 3.3V voltage output terminal of the second voltage conversion circuit module 3-3, the other end of the 3 rd pin, the 4 th pin, and the non-polar capacitor CX3 of the processor monitor chip MAX690_ ESA are grounded, the 6 th pin of the processor monitor chip MAX _ ESA is connected to the 131 th pin of the DSP chip TMS320F2812 and to the 3.3V voltage output terminal of the second voltage conversion circuit module 3-3 through the resistor RX9, the 7 th pin of the processor monitor chip MAX _ ESA, the anode DT1, the one end of the resistor RX8, and the one end of the non-polar capacitor CX4 of the processor monitor chip MAX690_ ESA are connected to the 3.3.3V voltage output terminal 2812 of the DSP chip CX 281320, the cathode of the switching diode DT1 and the other end of the resistor RX8 are both connected to the 3.3V voltage output terminal of the second voltage conversion circuit module 3-3, and the other end of the non-polar capacitor CX4 is grounded.

In this embodiment, as shown in fig. 7, the angle measurement module 4 includes a three-dimensional angle sensor MPU-6050, a non-polar capacitor C17, a non-polar capacitor C18, a non-polar capacitor C19, a resistor R18, and a resistor R19, one end of the 8 th pin, the 13 th pin, and the non-polar capacitor C17 of the three-dimensional angle sensor MPU-6050 are all connected to the 3.3V voltage output terminal of the first voltage conversion circuit module 3-2, the other end of the 1 st pin, the 11 th pin, the 18 th pin, and the non-polar capacitor C17 of the three-dimensional angle sensor MPU-6050 are all grounded, the 10 th pin of the three-dimensional angle sensor MPU-6050 is grounded through the non-polar capacitor C18, the 20 th pin of the three-dimensional angle sensor MPU-6050 is grounded through the non-polar capacitor C19, the 23 rd pin of the three-dimensional angle sensor MPU-6050 is connected to the 3.3V voltage output terminal of the first voltage conversion circuit module 3-2 through the, and the pin 24 of the three-dimensional angle sensor MPU-6050 is connected with the voltage output end of 3.3V of the first voltage conversion circuit module 3-2 through a resistor R18 and is connected with the pin 157 of the DSP chip TMS320F2812, and the pin 6, the pin 7, the pin 9 and the pin 12 of the three-dimensional angle sensor MPU-6050 are sequentially connected with the pin 155, the pin 34, the pin 127 and the pin 79 of the DSP chip TMS320F2812 correspondingly.

In this embodiment, as shown in fig. 8, the key circuit module 5 includes a key S1, a key S2, a resistor R23, and a resistor R24, one end of the key S1 is connected to the 3.3V voltage output terminal of the first voltage conversion circuit module 3-2 through a resistor R23 and is connected to the 18 th pin of the DSP chip TMS320F2812, one end of the key S2 is connected to the 3.3V voltage output terminal of the first voltage conversion circuit module 3-2 through a resistor R24 and is connected to the 43 th pin of the DSP chip TMS320F2812, and the other end of the key S1 and the other end of the key S2 are both grounded.

In this embodiment, as shown in fig. 9, the display module 6 includes a TFT display screen U5, a 31 st pin of the TFT display screen U5 is connected to a 3.3V voltage output terminal of the first voltage conversion circuit module 3-2, a1 st pin and a 32 nd pin of the TFT display screen U5 are both grounded, and a2 nd pin, a3 rd pin, a4 th pin, a5 th pin, a6 th pin, a 7 th pin, an 8 th pin, a 9 th pin, a 10 th pin, an 11 th pin, a 12 th pin, a 13 th pin, a 14 th pin, a 15 th pin, a 16 th pin, a 17 th pin, an 18 th pin, a 19 th pin, a 20 th pin, a 21 st pin, a 22 nd pin, a 23 th pin, a 24 th pin, a 25 th pin, a 26 th pin, a 27 th pin, and a 28 th pin of the TFT display screen U5F 2812 sequentially correspond to a 66 th pin, a 147 th pin, a 139 th pin, a 147 th pin, a 97 th pin, a fifth pin, a second pin, The 96 th pin, the 74 th pin, the 73 th pin, the 68 th pin, the 65 th pin, the 54 th pin, the 39 th pin, the 36 th pin, the 33 th pin, the 30 th pin, the 27 th pin, the 24 th pin, the 21 st pin, the 42 th pin, the 51 st pin, the 160 th pin, the 44 th pin, the 136 th pin, the 88 th pin, the 123 th pin, the 122 th pin, the 110 th pin and the 92 th pin.

In this embodiment, as shown in fig. 10, the first Zigbee wireless communication module 7 includes a Zigbee wireless communication module U6 with a model number CC2530, a VCC pin of the Zigbee wireless communication module U6 is connected to a 3.3V voltage output terminal of the first voltage conversion circuit module 3-2, a GND pin of the Zigbee wireless communication module U6 is grounded, a TX pin of the Zigbee wireless communication module U6 is connected to a 91 th pin of the DSP chip TMS320F2812, and an RX pin of the Zigbee wireless communication module U6 is connected to a 90 th pin of the DSP chip TMS320F 2812.

The method of the steering auxiliary system of the automobile steering wheel comprises a steering wheel rotating angle identification method for assisting a driver to correctly identify the steering wheel rotating angle and a method for assisting the driver to control the steering wheel by controlling a power-assisted steering motor 11 by an ARM microcontroller 8 when the steering transmission ratio of the steering wheel is abnormally changed;

step A2, pasting the back of the shell 1 of the automobile steering wheel rotation angle measuring unit at the middle position of the automobile steering wheel;

step A3, the automobile steering wheel is rotated to the left side, when the automobile steering wheel rotates 45 degrees, the key S1 in the key circuit module 5 is pressed once, the angle measuring module 4 detects the current angle information and transmits the current angle information to the DSP processor module 2 for recording and storing until the automobile steering wheel rotates to the left limit;

step A5, the automobile steering wheel is rotated to the right side, when the automobile steering wheel rotates 45 degrees, the key S2 in the key circuit module 5 is pressed once, the angle measuring module 4 detects the current angle information and transmits the current angle information to the DSP processor module 2 for recording and storing until the automobile steering wheel rotates to the right limit;

step A6, after the automobile is started, detecting the rotation angle of the automobile steering wheel in real time by the angle measuring module 4, when the driver turns the steering wheel to the left, displaying the left arrow by the display module 6, and simultaneously displaying the rotation angle, when the driver needs to turn the steering wheel to the right, the left arrow is still lighted, and prompting that the current steering wheel is still in the left angle area, and the right arrow is lighted to prompt that the current steering wheel is rotated to the right until the steering wheel turns to the initial position, and both the left arrow and the right arrow are extinguished; when a driver turns a steering wheel to the right, the display module 6 displays a rightward arrow and simultaneously displays a rotation angle, when the driver needs to turn the steering wheel to the left, the rightward arrow is still lightened to prompt that the current steering wheel is still in a right angle area, and meanwhile, the leftward arrow can be lightened to prompt that the current steering wheel is rotated to the left until the steering wheel is turned back to an initial position, and the leftward arrow and the rightward arrow are both extinguished;

the ARM microcontroller 8 controls the power steering motor 11, and the method for assisting a driver in steering wheel control comprises the following steps:

step B1, when the automobile steering wheel rotates, the magnetostrictive displacement sensor 10 arranged on the steering pull rod of the automobile steering wheel detects the translation distance value of the steering pull rod, and the ARM microcontroller 8 collects the detected translation distance value; angle measuring module 4 in a steering wheel rotation angle measuring unit mounted on a steering wheel of a motor vehicle detects a rotation angle value e of the steering wheel of the motor vehicle₁And the detected steering wheel rotation angle value e is detected through a first Zigbee wireless communication module 7 and a second Zigbee wireless communication module 9 which are in wireless connection and communication₁Transmitting to ARM microcontroller 8;

step B2, the ARM microcontroller 8 obtains the rotation angle of the automobile tire from the stored data according to the preset corresponding data of the translation distance of the steering rod and the rotation angle of the automobile tire, and the specific process is as follows:

step B202, storing corresponding data of the translation distances of the multiple groups of steering pull rods and the rotation angles of the automobile tires into an ARM microcontroller 8;

step B203, when the magnetostrictive displacement sensor 10 detects the translation distance value of the steering pull rod, the ARM microcontroller 8 acquires the rotation angle of the automobile tire from the stored data;

step B3, the ARM microcontroller 8 calculates the rotation angle value e of the automobile steering wheel according to the steering transmission ratio between the steering degree of the automobile steering wheel and the steering degree of the tires₂；

In practice, if one rotation of the steering wheel of the automobile leads to the automobile tyre turning 20 degrees, the steering transmission ratio is equal to 360 divided by 20, namely 18:1, and the rotation angle value e of the automobile steering wheel₂Is equal to the rotation angle of the car tyre multiplied by 18；

Step B4, the ARM microcontroller 8 detects the steering wheel rotation angle value e according to the automobile steering wheel rotation angle measuring unit₁And the steering wheel rotation angle value e calculated by the automobile tire rotation angle measuring unit₂The method is characterized in that optimized fuzzy neural network PID control is implemented on the power-assisted steering motor 11 on the steering pull rod, and the specific process is as follows:

step B401, the ARM microcontroller 8 calculates e₁And e₂E is equal to e₁-e₂(ii) a Calculating the difference change rate ec ═ e₁-e₂)/e₁；

step B407, outputting the optimized control voltage U of the power-assisted steering motor 11 by an output layer in the PID neural network^*。

In specific implementation, U^*＝K_Pe(k)+K_I∑e(k)+K_D[e(k)-e(k-1)]Wherein e (k) is the difference at the k-th sampling, e (k-1) is the difference at the k-1-th sampling, k is the sampling number, k is 0,1,2,3 …;

the specific process of optimizing the weight of the PID neural network by adopting the improved bacterial foraging optimization algorithm in the step B406 of the invention is as follows:

step B4061, initializing bacterial foraging optimization algorithm parameters: the bacterial foraging optimization algorithm parameters comprise a search working dimension p of a total bacterial count S, PID control parameter corresponding to a PID control parameter in a bacterial flora and chemotaxis times N of the PID control parameter_cMaximum step number N of one-way movement of PID control parameter in chemotaxis process_SPID control parameter copy number N_reAnd learning frequency N of PID control parameter_edMaximum chemotaxis step length C of PID control parameter_maxAnd minimum chemotaxis step size C of PID control parameter_min；

step B4063, updating the fitness value: according to the formula

step B4064, setting parameters of circulation variables: wherein the chemotaxis cycle number j is 1 to N_cThe number of reproduction cycles k is 1 to N_reLearning cycleThe number of cycles l is 1 to N_ed；

step Q22, calculating the fitness value of the bacterium i;

step Q24, initializing j to 1;

step Q25, calculating the fitness value of the bacteria i at the new position;

step Q27, reassigning j to j + 1;

step Q29, updating the fitness value of the bacterium i;

step Q212, the chemotaxis operation is finished;

step Q12, calculating the fitness value of the bacterium i;

step Q13, according to the formula

Calculating a bacterial flora density function factor D (i), and calculating a chemotaxis step length C (i) according to a formula C (i) ═ A.D (i) + B; then turning bacterium i by step length C (i) in the direction of random generation; wherein, L is the maximum length in the diagonal line of the search space, X (m, i) is the position coordinate value of the bacterium i in the mth dimension of the search space, and X is the average position coordinate value of all bacteria in the current search space in the mth dimension of the search space;

step Q14, initializing j to 1;

step Q15, calculating the fitness value of the bacteria i at the new position;

step Q17, reassigning j to j + 1;

step Q19, updating the fitness value of the bacterium i;

step Q112, the chemotaxis operation is finished;

step F13, sequencing the bacteria according to the quality of the health value;

f14, jumping to execute the step F11;

step F15, eliminating the poor health

Bacteria, the rest

step F16, the copying operation is finished;

Step F24, obtaining from daughter bacterial flora X'₂Fungus group X₂In the selection of fitnessReplacement of the original bacterial group X by the best-valued first S bacteria₂；

Step B4067, entering a learning cycle to perform learning operation, wherein the specific method comprises the following steps: bacterial group X₁With the bacterium group X₂The bacteria in (1) are sequenced, and the flora X is₁The first 61.8% of the bacteria were selected to be 0.382S bacteria and group X according to roulette' S method₂The second 38.2% of the bacteria are exchanged, and the exchanged 0.382S bacteria form a new flora X₂；

In order to verify the effect that the steering auxiliary system and the method for the automobile steering wheel can generate, MATLAB software is adopted to control the power steering motor 11 of the ARM microcontroller 8, the method for assisting the driver in steering wheel control is simulated, and a comparison graph of the effect of the method of the invention obtained through simulation and the effect of fuzzy PID control, PID control and fuzzy neural PID control is shown in FIG. 12. As can be seen from fig. 12, the effect of the present invention is superior to the fuzzy PID control, the PID control, and the fuzzy neural PID control.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. An automobile steering wheel steering auxiliary method is characterized in that an automobile steering wheel steering auxiliary system comprises an automobile steering wheel rotating angle measuring unit, an automobile tire rotating angle measuring unit and an automobile steering wheel steering auxiliary control unit, wherein the automobile steering wheel rotating angle measuring unit comprises a shell (1) arranged in the middle of a steering wheel and a circuit board arranged in the shell (1), a measuring circuit is integrated on the circuit board, the measuring circuit comprises a DSP processor module (2), a power circuit module (3) for supplying power to each power module in the measuring circuit, and a first Zigbee wireless communication module (7) connected with the DSP processor module (2); the input end of the DSP processor module (2) is connected with an angle measuring module (4) and a key circuit module (5), the output end of the DSP processor module (2) is connected with a display module (6), the power circuit module (3) comprises a lithium battery (3-1), a first voltage conversion circuit module (3-2) which is connected with the output end of the lithium battery (3-1) and used for converting 3.7V voltage into 3.3V voltage, and a second voltage conversion circuit module (3-3) which is connected with the output end of the lithium battery (3-1) and used for converting 3.7V voltage into 3.3V voltage and 1.9V voltage, the DSP processor module (2) is connected with the output end of the second voltage conversion circuit module (3-3), and the angle measuring module (4), the key circuit module (5), the display module (6) and the first Zigbee wireless communication module (7) are all connected with the first voltage conversion circuit module (3-2) ) Connecting; the automobile tire rotation angle measuring unit comprises an ARM microcontroller (8) and a second Zigbee wireless communication module (9) which is connected with the ARM microcontroller (8) and is used for being in wireless connection and communication with the first Zigbee wireless communication module (7), wherein the input end of the ARM microcontroller (8) is connected with a magnetostrictive displacement sensor (10) which is arranged on a steering pull rod of an automobile steering wheel; the automobile steering wheel steering auxiliary control unit comprises a power-assisted steering motor (11) installed on a steering pull rod of the automobile steering wheel, the power-assisted steering motor (11) is connected with the output end of an ARM microcontroller (8) through a motor driving module (12), and the automobile steering wheel steering auxiliary control unit is characterized in that: the method comprises a steering wheel rotation angle identification method for assisting a driver to correctly identify the steering wheel rotation angle and a method for assisting the driver to control the steering wheel by controlling a power-assisted steering motor (11) by an ARM microcontroller (8) when the steering transmission ratio of the steering wheel is abnormally changed;

a2, sticking the back of the shell (1) of the automobile steering wheel rotation angle measuring unit at the middle position of the automobile steering wheel;

step A3, the automobile steering wheel is rotated to the left side, when the automobile steering wheel rotates 45 degrees, the key S1 in the key circuit module (5) is pressed once, the angle measuring module (4) detects the current angle information and transmits the current angle information to the DSP processor module (2) for recording and storing until the automobile steering wheel rotates to the left limit;

step A5, the automobile steering wheel is rotated to the right side, when the automobile steering wheel rotates 45 degrees, the key S2 in the key circuit module (5) is pressed once, the angle measuring module (4) detects the current angle information and transmits the current angle information to the DSP processor module (2) for recording and storing until the automobile steering wheel rotates to the right limit;

step A6, after the automobile is started, detecting the rotation angle of an automobile steering wheel in real time by an angle measuring module (4), when a driver turns the steering wheel to the left, displaying a left arrow by a display module (6) and simultaneously displaying a rotation angle, when the driver needs to turn the steering wheel to the right, still lighting the left arrow to prompt that the current steering wheel is still in a left angle area, and simultaneously flashing the right arrow to prompt that the current steering wheel is rotated to the right until the steering wheel is turned back to an initial position, and turning off both the left arrow and the right arrow; when a driver turns a steering wheel to the right, the display module (6) displays a rightward arrow and simultaneously displays a rotation angle, when the driver needs to turn the steering wheel to the left, the rightward arrow is still lightened to prompt that the current steering wheel is still in a right angle area, and meanwhile, the leftward arrow can be lightened to prompt that the steering wheel is currently turned to the left until the steering wheel is turned to the initial position, and the leftward arrow and the rightward arrow are both extinguished;

the ARM microcontroller (8) controls a power steering motor (11), and the method for assisting a driver in steering wheel control comprises the following steps:

step B1, when the automobile steering wheel rotates, the magnetostrictive displacement sensor (10) arranged on the steering pull rod of the automobile steering wheel detects the position of the steering pull rodThe translation distance value is acquired by an ARM microcontroller (8); an angle measuring module (4) in a steering wheel rotation angle measuring unit mounted on a steering wheel of a motor vehicle detects a rotation angle value e of the steering wheel of the motor vehicle₁And the detected steering wheel rotation angle value e is detected through a first Zigbee wireless communication module (7) and a second Zigbee wireless communication module (9) which are in wireless connection and communication₁Transmitting the data to an ARM microcontroller (8);

step B2, the ARM microcontroller (8) obtains the rotation angle of the automobile tire from the stored data according to the preset corresponding data of the translation distance of the steering rod and the rotation angle of the automobile tire, and the specific process is as follows:

step B202, storing corresponding data of the translation distances of the multiple groups of steering pull rods and the rotation angles of the automobile tires into an ARM microcontroller (8);

step B203, when the magnetostrictive displacement sensor (10) detects the translation distance value of the steering pull rod, the ARM microcontroller (8) acquires the rotation angle of the automobile tire from the stored data;

step B3, the ARM microcontroller (8) calculates the rotation angle value e of the automobile steering wheel according to the steering transmission ratio between the steering degree of the automobile steering wheel and the steering degree of the tire₂；

Step B4, the ARM microcontroller (8) detects the steering wheel rotation angle value e according to the automobile steering wheel rotation angle measuring unit₁And the steering wheel rotation angle value e calculated by the automobile tire rotation angle measuring unit₂The method is characterized in that optimized fuzzy neural network PID control is implemented on a power-assisted steering motor (11) on a steering pull rod, and the specific process is as follows:

step B401, the ARM microcontroller (8) calculates e₁And e₂E is equal to e₁-e₂(ii) a Calculating the difference change rate ec ═ e₁-e₂)/e₁；

step B407, outputting the control voltage U optimized to the power-assisted steering motor (11) by an output layer in the PID neural network^*。

2. A steering assist method for a steering wheel of an automobile according to claim 1, wherein: the battery pack is characterized in that the shell (1) is cylindrical, a plurality of exposed holes for the key circuit module (5) and the display module (6) are formed in the upper surface of the shell (1), and a miniUSB interface hole for charging the lithium battery (3-1) is formed in the side surface of the shell (1).

3. A steering assist method for a steering wheel of an automobile according to claim 1, wherein: the first voltage conversion circuit module (3-2) comprises a 3.3V linear voltage regulator Q2, a nonpolar capacitor C10, a nonpolar capacitor C11, a nonpolar capacitor C12, a light emitting diode D1 and a resistor R21, the No. 1 pin and the No. 3 pin of the linear voltage stabilizer Q2 and one end of the nonpolar capacitor C11 are connected with the 3.7V voltage output end of the lithium battery (3-1), the 2 nd pin of the linear voltage regulator Q2 and the other end of the non-polar capacitor C11 are both grounded, the 5 th pin of the linear voltage regulator Q2 is the 3.3V voltage output end of the first voltage conversion circuit module (3-2), and one end of the nonpolar capacitor C10, one end of the nonpolar capacitor C12 and one end of the resistor R21 are all connected, the other end of the resistor R21 is connected with the anode of the light-emitting diode D1, and the other end of the nonpolar capacitor C10, the other end of the nonpolar capacitor C12 and the cathode of the light-emitting diode D1 are all grounded; the second voltage conversion circuit module (3-3) comprises a voltage regulator TPS767D301, a polar capacitor CT1, a polar capacitor CT2, a polar capacitor CT3, a polar capacitor CT4, a non-polar capacitor C7, a non-polar capacitor C8, a non-polar capacitor C9, a non-polar capacitor C13, a non-polar capacitor C14, a non-polar capacitor C15, a non-polar capacitor C16, an inductor L1, an inductor L2, a resistor R16 and a resistor R17, wherein the 5 th pin, the 6 th pin, the 11 th pin, the 12 th pin of the voltage regulator TPS767D301, a positive electrode of the polar capacitor CT1, one end of the non-polar capacitor C13 and one end of the non-polar capacitor C14 are all connected with a 3.7V voltage output end of a lithium battery (3-1), the 3 rd pin, the 4 th pin, the 9 th pin, the 10 th pin, the 29 th pin, the negative electrode of the polar capacitor CT 42, the other end of the non-polar capacitor C13 and the non-polar capacitor C14 of the non-polar capacitor C13 are, a 23 th pin of the voltage regulator TPS767D301 is a 1.9V voltage output end of the second voltage conversion circuit module (3-3), and is connected to a 24 th pin of the voltage regulator TPS767D301, one end of the resistor R16, a positive electrode of the polar capacitor CT2, one end of the non-polar capacitor C7, and one end of the inductor L1, a 25 th pin of the voltage regulator TPS767D301 and the other end of the resistor R16 are connected to one end of the resistor R17, a negative electrode of the polar capacitor CT2, the other end of the non-polar capacitor C7, and the other end of the resistor R17 are all grounded, the other end of the inductor L1 is grounded through the non-polar capacitor C15, a 17 th pin of the voltage regulator TPS767D301 is a 3.3V voltage output end of the second voltage conversion circuit module (3-3), and is connected to a 18 th pin of the voltage regulator TPS767D301, a positive electrode of the polar capacitor CT3, one end of the non-polar capacitor C8, and a positive electrode of the polar capacitor CT4, One end of the non-polar capacitor C9 and one end of the inductor L2 are all connected, the 19 th pin of the voltage regulator TPS767D301, the negative electrode of the polar capacitor CT3, the other end of the non-polar capacitor C8, the negative electrode of the polar capacitor CT4, and the other end of the non-polar capacitor C9 are all grounded, and the other end of the inductor L2 is grounded through the non-polar capacitor C16.

4. A steering assist method for a steering wheel of an automobile according to claim 3, wherein: DSP processor module (2) includes DSP chip TMS320F2812, crystal oscillator Y1, non-polar electric capacity CX1 and non-polar electric capacity CX2, and the reset circuit who meets with DSP chip TMS320F2812, crystal oscillator Y1's one end and non-polar electric capacity CX 1's one end all are connected with DSP chip TMS320F 2812's 77 th pin, crystal oscillator Y1's the other end and non-polar electric capacity CX 2's one end all are connected with DSP chip TMS320F 2812's 76 th pin, non-polar electric capacity CX 1's the other end and non-polar electric capacity CX 2's the other end all ground connection, DSP chip TMS320F 2812's 31 st pin, 64 th pin, 69 th pin, 81 th pin, 114 th pin and 145 th pin all are connected with the 3.3V voltage output terminal of second voltage conversion circuit module (3-3), DSP chip TMS320F 2812's 23 th pin, 37 th pin, 56 th pin, 75 th pin, 100 th pin, 143 th pin, 112 th pin and the equal voltage output terminal of second voltage conversion circuit module (3.3-3.3.3V) voltage conversion module (voltage output terminal) of DSP The 19 th pin, the 32 th pin, the 38 th pin, the 52 th pin, the 58 th pin, the 70 th pin, the 78 th pin, the 86 th pin, the 99 th pin, the 105 th pin, the 113 th pin, the 120 th pin, the 129 th pin, the 142 th pin and the 153 th pin of the DSP chip TMS320F2812 are all grounded; the reset circuit (3) comprises a processor monitor chip MAX690_ ESA, a switch diode DT1, a non-polar capacitor CX3, a non-polar capacitor CX4, a resistor RX8 and a resistor RX9, wherein one end of the No. 1 pin, the No. 2 pin, the No. 8 pin and the non-polar capacitor CX3 of the processor monitor chip MAX690_ ESA are connected with the 3.3V voltage output end of the second voltage conversion circuit module (3-3), the other ends of the No. 3 pin, the No. 4 pin and the non-polar capacitor CX3 of the processor monitor chip MAX690_ ESA are grounded, the No. 6 pin of the processor monitor chip 690_ ESA is connected with the No. 131 pin of the DSP chip TMS320F2812 and is connected with the 3.3V voltage output end of the second voltage conversion circuit module (3-3) through the resistor RX9, the No. 7 pin of the processor monitor chip MAX _ ESA, the anode of the switch diode DT 732, one end of the resistor RX8 and one end of the non-polar capacitor CX 35 1 are connected with the No. 7 pin of the DSP chip 281320F 281, the cathode of the switching diode DT1 and the other end of the resistor RX8 are both connected with the 3.3V voltage output end of the second voltage conversion circuit module (3-3), and the other end of the nonpolar capacitor CX4 is grounded.

5. A steering assist method for a steering wheel of an automobile according to claim 4, wherein: the angle measurement module (4) comprises a three-dimensional angle sensor MPU-6050, a nonpolar capacitor C17, a nonpolar capacitor C18, a nonpolar capacitor C19, a resistor R18 and a resistor R19, one ends of a No. 8 pin, a No. 13 pin and a nonpolar capacitor C17 of the three-dimensional angle sensor MPU-6050 are all connected with a 3.3V voltage output end of a first voltage conversion circuit module (3-2), the other ends of a No. 1 pin, a No. 11 pin, a No. 18 pin and a nonpolar capacitor C17 of the three-dimensional angle sensor MPU-6050 are all grounded, a No. 10 pin of the three-dimensional angle sensor MPU-6050 is grounded through the nonpolar capacitor C18, a No. 20 pin of the three-dimensional angle sensor MPU-6050 is grounded through the nonpolar capacitor C19, a No. 23 pin of the three-dimensional angle sensor MPU-6050 is connected with a 3.3V voltage output end of the first voltage conversion circuit module (3-2) through a resistor R19, and the 24 th pin of the three-dimensional angle sensor MPU-6050 is connected with the 3.3V voltage output end of the first voltage conversion circuit module (3-2) through a resistor R18 and is connected with the 157 th pin of the DSP chip TMS320F2812, and the 6 th pin, the 7 th pin, the 9 th pin and the 12 th pin of the three-dimensional angle sensor MPU-6050 are sequentially connected with the 155 th pin, the 34 th pin, the 127 th pin and the 79 th pin of the DSP chip TMS320F2812 correspondingly.

6. A steering assist method for a steering wheel of an automobile according to claim 4, wherein: the key circuit module (5) comprises a key S1, a key S2, a resistor R23 and a resistor R24, one end of the key S1 is connected with a 3.3V voltage output end of the first voltage conversion circuit module (3-2) through a resistor R23 and is connected with an 18 th pin of a DSP chip TMS320F2812, one end of the key S2 is connected with a 3.3V voltage output end of the first voltage conversion circuit module (3-2) through a resistor R24 and is connected with a 43 th pin of the DSP chip TMS320F2812, and the other end of the key S1 and the other end of the key S2 are both grounded.

7. A steering assist method for a steering wheel of an automobile according to claim 4, wherein: the display module (6) comprises a TFT display screen U5, a 31 st pin of the TFT display screen U5 is connected with a 3.3V voltage output end of a first voltage conversion circuit module (3-2), a1 st pin and a 32 nd pin of the TFT display screen U5 are both grounded, and a2 nd pin, a3 rd pin, a4 th pin, a5 th pin, a6 th pin, a 7 th pin, an 8 th pin, a 9 th pin, a 10 th pin, an 11 th pin, a 12 th pin, a 13 th pin, a 14 th pin, a 15 th pin, a 16 th pin, a 17 th pin, an 18 th pin, a 19 th pin, a 20 th pin, a 21 st pin, a 22 nd pin, a 23 rd pin, a 24 th pin, a 25 th pin, a 26 th pin, a 27 th pin and a 28 th pin of the TFT display screen U5 correspond to a 66 th pin, a 147 th pin, a 139 th pin, a 97 th pin, a 96 th pin, a 74 th pin, a 28 th pin, a TMS320F2812 of the DSP chip sequentially, The 73 rd pin, the 68 th pin, the 65 th pin, the 54 th pin, the 39 th pin, the 36 th pin, the 33 rd pin, the 30 th pin, the 27 th pin, the 24 th pin, the 21 st pin, the 42 th pin, the 51 st pin, the 160 th pin, the 44 th pin, the 136 th pin, the 88 th pin, the 123 th pin, the 122 th pin, the 110 th pin and the 92 th pin are connected.

8. A steering assist method for a steering wheel of an automobile according to claim 4, wherein: the first Zigbee wireless communication module (7) comprises a ZigBee wireless communication module U6 with the model number of CC2530, a VCC pin of the ZigBee wireless communication module U6 is connected with a 3.3V voltage output end of the first voltage conversion circuit module (3-2), a GND pin of the ZigBee wireless communication module U6 is grounded, a TX pin of the ZigBee wireless communication module U6 is connected with a 91 th pin of the DSP chip TMS320F2812, and an RX pin of the ZigBee wireless communication module U6 is connected with a 90 th pin of the DSP chip TMS320F 2812.

9. A steering assist method for a steering wheel of an automobile according to claim 1, wherein: the specific process of optimizing the weight of the PID neural network by using the improved bacterial foraging optimization algorithm in step B406 is as follows:

step B4063, updating the fitness value: according to the formula

Calculating the fitness value of each bacterium; wherein d is_attractDepth of attraction between bacteria, w_attractWidth of attraction between bacteria, h_repellentHeight of repulsion between bacteria, w_repellentThe width of the repulsion between bacteria, P (i, J, k, l) is the position of the bacteria i after the jth tropism operation, the kth replication operation and the ith migration operation, P (1: S, J, k, l) is a random position in the neighborhood of the current individual P (i, J, k, l), J (1: S, J, k, l)_CC(i, j, k, l) is the bacterial i in the jth tropism operation, kth replication operation and the l migration operationA fitness value after the operation;

step Q22, calculating the fitness value of the bacterium i;

step Q24, initializing j to 1;

step Q25, calculating the fitness value of the bacteria i at the new position;

step Q27, reassigning j to j + 1;

step Q29, updating the fitness value of the bacterium i;

step Q212, the chemotaxis operation is finished;

step Q12, calculating the fitness value of the bacterium i;

step Q13, according to the formula

Calculating a bacterial flora density function factor D (i), and calculating a chemotaxis step length C (i) according to a formula C (i) ═ A.D (i) + B; then turning bacterium i by step length C (i) in the direction of random generation; wherein L is the maximum length in the diagonal of the search space, X (m, i) is the position coordinate value of the bacterium i in the m-th dimension of the search space,

the average position coordinate value of all bacteria in the current search space in the mth dimension of the search space is obtained;

step Q14, initializing j to 1;

step Q15, calculating the fitness value of the bacteria i at the new position;

step Q17, reassigning j to j + 1;

step Q19, updating the fitness value of the bacterium i;

step Q112, the chemotaxis operation is finished;

against bacterial flora X₁According to the following steps F11 to F16Replication operations replicate each bacterium:

step F13, sequencing the bacteria according to the quality of the health value;

f14, jumping to execute the step F11;

step F15, eliminating the poor health

Bacteria, the rest

step F16, the copying operation is finished;