今天跟大家帶來熟數字濾波算法:
1、限幅濾波法(又稱程序判斷濾波法)
/*A、名稱:限幅濾波法(又稱程序判斷濾波法)B、方法:根據經驗判斷,確定兩次采樣允許的最大偏差值(設為A),每次檢測到新值時判斷:如果本次值與上次值之差<=A,則本次值有效,如果本次值與上次值之差>A,則本次值無效,放棄本次值,用上次值代替本次值。C、優點:能有效克服因偶然因素引起的脈沖干擾。D、缺點:無法抑制那種周期性的干擾。平滑度差。E、整理:shenhAIyu 2013-11-01*/int Filter_Value;int Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子Value = 300;}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Value = Filter_Value; // 最近一次有效采樣的值,該變量為全局變量Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 限幅濾波法(又稱程序判斷濾波法)#define FILTER_A 1int Filter() {int NewValue;NewValue = Get_AD();if(((NewValue - Value) > FILTER_A) || ((Value - NewValue) > FILTER_A))return Value;elsereturn NewValue;}
2、中位值濾波法
/*A、名稱:中位值濾波法B、方法:連續采樣N次(N取奇數),把N次采樣值按大小排列,取中間值為本次有效值。C、優點:能有效克服因偶然因素引起的波動干擾;對溫度、液位的變化緩慢的被測參數有良好的濾波效果。D、缺點:對流量、速度等快速變化的參數不宜。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 中位值濾波法#define FILTER_N 101int Filter() {int filter_buf[FILTER_N];int i, j;int filter_temp;for(i = 0; i < FILTER_N; i++) {filter_buf[i] = Get_AD();delay(1);}// 采樣值從小到大排列(冒泡法)for(j = 0; j < FILTER_N - 1; j++) {for(i = 0; i < FILTER_N - 1 - j; i++) {if(filter_buf[i] > filter_buf[i + 1]) {filter_temp = filter_buf[i];filter_buf[i] = filter_buf[i + 1];filter_buf[i + 1] = filter_temp;}}}return filter_buf[(FILTER_N - 1) / 2];}
3、算術平均濾波法
/*A、名稱:算術平均濾波法B、方法:連續取N個采樣值進行算術平均運算:N值較大時:信號平滑度較高,但靈敏度較低;N值較小時:信號平滑度較低,但靈敏度較高;N值的選取:一般流量,N=12;壓力:N=4。C、優點:適用于對一般具有隨機干擾的信號進行濾波;這種信號的特點是有一個平均值,信號在某一數值范圍附近上下波動。D、缺點:對于測量速度較慢或要求數據計算速度較快的實時控制不適用;比較浪費RAM。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 算術平均濾波法#define FILTER_N 12int Filter() {int i;int filter_sum = 0;for(i = 0; i < FILTER_N; i++) {filter_sum += Get_AD();delay(1);}return (int)(filter_sum / FILTER_N);}
4、遞推平均濾波法(又稱滑動平均濾波法)
/*A、名稱:遞推平均濾波法(又稱滑動平均濾波法)B、方法:把連續取得的N個采樣值看成一個隊列,隊列的長度固定為N,每次采樣到一個新數據放入隊尾,并扔掉原來隊首的一次數據(先進先出原則),把隊列中的N個數據進行算術平均運算,獲得新的濾波結果。N值的選取:流量,N=12;壓力,N=4;液面,N=4-12;溫度,N=1-4。C、優點:對周期性干擾有良好的抑制作用,平滑度高;適用于高頻振蕩的系統。D、缺點:靈敏度低,對偶然出現的脈沖性干擾的抑制作用較差;不易消除由于脈沖干擾所引起的采樣值偏差;不適用于脈沖干擾比較嚴重的場合;比較浪費RAM。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 遞推平均濾波法(又稱滑動平均濾波法)#define FILTER_N 12int filter_buf[FILTER_N + 1];int Filter() {int i;int filter_sum = 0;filter_buf[FILTER_N] = Get_AD();for(i = 0; i < FILTER_N; i++) {filter_buf[i] = filter_buf[i + 1]; // 所有數據左移,低位仍掉filter_sum += filter_buf[i];}return (int)(filter_sum / FILTER_N);}
5、中位值平均濾波法(又稱防脈沖干擾平均濾波法)
/*A、名稱:中位值平均濾波法(又稱防脈沖干擾平均濾波法)B、方法:采一組隊列去掉最大值和最小值后取平均值,相當于“中位值濾波法”+“算術平均濾波法”。連續采樣N個數據,去掉一個最大值和一個最小值,然后計算N-2個數據的算術平均值。N值的選取:3-14。C、優點:融合了“中位值濾波法”+“算術平均濾波法”兩種濾波法的優點。對于偶然出現的脈沖性干擾,可消除由其所引起的采樣值偏差。對周期干擾有良好的抑制作用。平滑度高,適于高頻振蕩的系統。D、缺點:計算速度較慢,和算術平均濾波法一樣。比較浪費RAM。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 中位值平均濾波法(又稱防脈沖干擾平均濾波法)(算法1)#define FILTER_N 100int Filter() {int i, j;int filter_temp, filter_sum = 0;int filter_buf[FILTER_N];for(i = 0; i < FILTER_N; i++) {filter_buf[i] = Get_AD();delay(1);}// 采樣值從小到大排列(冒泡法)for(j = 0; j < FILTER_N - 1; j++) {for(i = 0; i < FILTER_N - 1 - j; i++) {if(filter_buf[i] > filter_buf[i + 1]) {filter_temp = filter_buf[i];filter_buf[i] = filter_buf[i + 1];filter_buf[i + 1] = filter_temp;}}}// 去除最大最小極值后求平均for(i = 1; i < FILTER_N - 1; i++) filter_sum += filter_buf[i];return filter_sum / (FILTER_N - 2);}// 中位值平均濾波法(又稱防脈沖干擾平均濾波法)(算法2)/*#define FILTER_N 100int Filter() {int i;int filter_sum = 0;int filter_max, filter_min;int filter_buf[FILTER_N];for(i = 0; i < FILTER_N; i++) {filter_buf[i] = Get_AD();delay(1);}filter_max = filter_buf[0];filter_min = filter_buf[0];filter_sum = filter_buf[0];for(i = FILTER_N - 1; i > 0; i--) {if(filter_buf[i] > filter_max)filter_max=filter_buf[i];else if(filter_buf[i] < filter_min)filter_min=filter_buf[i];filter_sum = filter_sum + filter_buf[i];filter_buf[i] = filter_buf[i - 1];}i = FILTER_N - 2;filter_sum = filter_sum - filter_max - filter_min + i / 2; // +i/2 的目的是為了四舍五入filter_sum = filter_sum / i;return filter_sum;}*/
6、限幅平均濾波法
/*A、名稱:限幅平均濾波法B、方法:相當于“限幅濾波法”+“遞推平均濾波法”;每次采樣到的新數據先進行限幅處理,再送入隊列進行遞推平均濾波處理。C、優點:融合了兩種濾波法的優點;對于偶然出現的脈沖性干擾,可消除由于脈沖干擾所引起的采樣值偏差。D、缺點:比較浪費RAM。E、整理:shenhaiyu 2013-11-01*/#define FILTER_N 12int Filter_Value;int filter_buf[FILTER_N];void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子filter_buf[FILTER_N - 2] = 300;}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 限幅平均濾波法#define FILTER_A 1int Filter() {int i;int filter_sum = 0;filter_buf[FILTER_N - 1] = Get_AD();if(((filter_buf[FILTER_N - 1] - filter_buf[FILTER_N - 2]) > FILTER_A) || ((filter_buf[FILTER_N - 2] - filter_buf[FILTER_N - 1]) > FILTER_A))filter_buf[FILTER_N - 1] = filter_buf[FILTER_N - 2];for(i = 0; i < FILTER_N - 1; i++) {filter_buf[i] = filter_buf[i + 1];filter_sum += filter_buf[i];}return (int)filter_sum / (FILTER_N - 1);}
7、一階滯后濾波法
/*A、名稱:一階滯后濾波法B、方法:取a=0-1,本次濾波結果=(1-a)*本次采樣值+a*上次濾波結果。C、優點:對周期性干擾具有良好的抑制作用;適用于波動頻率較高的場合。D、缺點:相位滯后,靈敏度低;滯后程度取決于a值大小;不能消除濾波頻率高于采樣頻率1/2的干擾信號。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;int Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子Value = 300;}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 一階滯后濾波法#define FILTER_A 0.01int Filter() {int NewValue;NewValue = Get_AD();Value = (int)((float)NewValue * FILTER_A + (1.0 - FILTER_A) * (float)Value);return Value;}
8、加權遞推平均濾波法
/*A、名稱:加權遞推平均濾波法B、方法:是對遞推平均濾波法的改進,即不同時刻的數據加以不同的權;通常是,越接近現時刻的數據,權取得越大。給予新采樣值的權系數越大,則靈敏度越高,但信號平滑度越低。C、優點:適用于有較大純滯后時間常數的對象,和采樣周期較短的系統。D、缺點:對于純滯后時間常數較小、采樣周期較長、變化緩慢的信號;不能迅速反應系統當前所受干擾的嚴重程度,濾波效果差。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 加權遞推平均濾波法#define FILTER_N 12int coe[FILTER_N] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}; // 加權系數表int sum_coe = 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12; // 加權系數和int filter_buf[FILTER_N + 1];int Filter() {int i;int filter_sum = 0;filter_buf[FILTER_N] = Get_AD();for(i = 0; i < FILTER_N; i++) {filter_buf[i] = filter_buf[i + 1]; // 所有數據左移,低位仍掉filter_sum += filter_buf[i] * coe[i];}filter_sum /= sum_coe;return filter_sum;}
9、消抖濾波法
/*A、名稱:消抖濾波法B、方法:設置一個濾波計數器,將每次采樣值與當前有效值比較:如果采樣值=當前有效值,則計數器清零;如果采樣值<>當前有效值,則計數器+1,并判斷計數器是否>=上限N(溢出);如果計數器溢出,則將本次值替換當前有效值,并清計數器。C、優點:對于變化緩慢的被測參數有較好的濾波效果;可避免在臨界值附近控制器的反復開/關跳動或顯示器上數值抖動。D、缺點:對于快速變化的參數不宜;如果在計數器溢出的那一次采樣到的值恰好是干擾值,則會將干擾值當作有效值導入系統。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;int Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子Value = 300;}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 消抖濾波法#define FILTER_N 12int i = 0;int Filter() {int new_value;new_value = Get_AD();if(Value != new_value) {i++;if(i > FILTER_N) {i = 0;Value = new_value;}}elsei = 0;return Value;}
10、限幅消抖濾波法
/*A、名稱:限幅消抖濾波法B、方法:相當于“限幅濾波法”+“消抖濾波法”;先限幅,后消抖。C、優點:繼承了“限幅”和“消抖”的優點;改進了“消抖濾波法”中的某些缺陷,避免將干擾值導入系統。D、缺點:對于快速變化的參數不宜。E、整理:shenhaiyu 2013-11-01*/int Filter_Value;int Value;void setup() {Serial.begin(9600); // 初始化串口通信randomSeed(analogRead(0)); // 產生隨機種子Value = 300;}void loop() {Filter_Value = Filter(); // 獲得濾波器輸出值Serial.println(Filter_Value); // 串口輸出delay(50);}// 用于隨機產生一個300左右的當前值int Get_AD() {return random(295, 305);}// 限幅消抖濾波法#define FILTER_A 1#define FILTER_N 5int i = 0;int Filter() {int NewValue;int new_value;NewValue = Get_AD();if(((NewValue - Value) > FILTER_A) || ((Value - NewValue) > FILTER_A))new_value = Value;elsenew_value = NewValue;if(Value != new_value) {i++;if(i > FILTER_N) {i = 0;Value = new_value;}}elsei = 0;return Value;}
11、卡爾曼濾波(非擴展卡爾曼)
#include <Wire.h> // I2C library, gyroscope// Accelerometer ADXL345#define ACC (0x53) //ADXL345 ACC address#define A_TO_READ (6) //num of bytes we are going to read each time (two bytes for each axis)// Gyroscope ITG3200#define GYRO 0x68 // gyro address, binary = 11101000 when AD0 is connected to Vcc (see schematics of your breakout board)#define G_SMPLRT_DIV 0x15#define G_DLPF_FS 0x16#define G_INT_CFG 0x17#define G_PWR_MGM 0x3E#define G_TO_READ 8 // 2 bytes for each axis x, y, z// offsets are chip specific.int a_offx = 0;int a_offy = 0;int a_offz = 0;int g_offx = 0;int g_offy = 0;int g_offz = 0;////////////////////////////////////////////////char str[512];void initAcc() {//Turning on the ADXL345writeTo(ACC, 0x2D, 0);writeTo(ACC, 0x2D, 16);writeTo(ACC, 0x2D, 8);//by default the device is in +-2g range reading}void getAccelerometerData(int* result) {int regAddress = 0x32; //first axis-acceleration-data register on the ADXL345byte buff[A_TO_READ];readFrom(ACC, regAddress, A_TO_READ, buff); //read the acceleration data from the ADXL345//each axis reading comes in 10 bit resolution, ie 2 bytes. Least Significat Byte first!!//thus we are converting both bytes in to one intresult[0] = (((int)buff[1]) << 8) | buff[0] + a_offx;result[1] = (((int)buff[3]) << 8) | buff[2] + a_offy;result[2] = (((int)buff[5]) << 8) | buff[4] + a_offz;}//initializes the gyroscopevoid initGyro(){/****************************************** ITG 3200* power management set to:* clock select = internal oscillator* no reset, no sleep mode* no standby mode* sample rate to = 125Hz* parameter to +/- 2000 degrees/sec* low pass filter = 5Hz* no interrupt******************************************/writeTo(GYRO, G_PWR_MGM, 0x00);writeTo(GYRO, G_SMPLRT_DIV, 0x07); // EB, 50, 80, 7F, DE, 23, 20, FFwriteTo(GYRO, G_DLPF_FS, 0x1E); // +/- 2000 dgrs/sec, 1KHz, 1E, 19writeTo(GYRO, G_INT_CFG, 0x00);}void getGyroscopeData(int * result){/**************************************Gyro ITG-3200 I2Cregisters:temp MSB = 1B, temp LSB = 1Cx axis MSB = 1D, x axis LSB = 1Ey axis MSB = 1F, y axis LSB = 20z axis MSB = 21, z axis LSB = 22*************************************/int regAddress = 0x1B;int temp, x, y, z;byte buff[G_TO_READ];readFrom(GYRO, regAddress, G_TO_READ, buff); //read the gyro data from the ITG3200result[0] = ((buff[2] << 8) | buff[3]) + g_offx;result[1] = ((buff[4] << 8) | buff[5]) + g_offy;result[2] = ((buff[6] << 8) | buff[7]) + g_offz;result[3] = (buff[0] << 8) | buff[1]; // temperature}float xz=0,yx=0,yz=0;float p_xz=1,p_yx=1,p_yz=1;float q_xz=0.0025,q_yx=0.0025,q_yz=0.0025;float k_xz=0,k_yx=0,k_yz=0;float r_xz=0.25,r_yx=0.25,r_yz=0.25;//int acc_temp[3];//float acc[3];int acc[3];int gyro[4];float Axz;float Ayx;float Ayz;float t=0.025;void setup(){Serial.begin(9600);Wire.begin();initAcc();initGyro();}//unsigned long timer = 0;//float o;void loop(){getAccelerometerData(acc);getGyroscopeData(gyro);//timer = millis();sprintf(str, "%d,%d,%d,%d,%d,%d", acc[0],acc[1],acc[2],gyro[0],gyro[1],gyro[2]);//acc[0]=acc[0];//acc[2]=acc[2];//acc[1]=acc[1];//r=sqrt(acc[0]*acc[0]+acc[1]*acc[1]+acc[2]*acc[2]);gyro[0]=gyro[0]/ 14.375;gyro[1]=gyro[1]/ (-14.375);gyro[2]=gyro[2]/ 14.375;Axz=(atan2(acc[0],acc[2]))*180/PI;Ayx=(atan2(acc[0],acc[1]))*180/PI;/*if((acc[0]!=0)&&(acc[1]!=0)){Ayx=(atan2(acc[0],acc[1]))*180/PI;}else{Ayx=t*gyro[2];}*/Ayz=(atan2(acc[1],acc[2]))*180/PI;//kalman filtercalculate_xz();calculate_yx();calculate_yz();//sprintf(str, "%d,%d,%d", xz_1, xy_1, x_1);//Serial.print(xz);Serial.print(",");//Serial.print(yx);Serial.print(",");//Serial.print(yz);Serial.print(",");//sprintf(str, "%d,%d,%d,%d,%d,%d", acc[0],acc[1],acc[2],gyro[0],gyro[1],gyro[2]);//sprintf(str, "%d,%d,%d",gyro[0],gyro[1],gyro[2]);Serial.print(Axz);Serial.print(",");//Serial.print(Ayx);Serial.print(",");//Serial.print(Ayz);Serial.print(",");//Serial.print(str);//o=gyro[2];//w=acc[2];//Serial.print(o);Serial.print(",");//Serial.print(w);Serial.print(",");Serial.print("n");//delay(50);}void calculate_xz(){xz=xz+t*gyro[1];p_xz=p_xz+q_xz;k_xz=p_xz/(p_xz+r_xz);xz=xz+k_xz*(Axz-xz);p_xz=(1-k_xz)*p_xz;}void calculate_yx(){yx=yx+t*gyro[2];p_yx=p_yx+q_yx;k_yx=p_yx/(p_yx+r_yx);yx=yx+k_yx*(Ayx-yx);p_yx=(1-k_yx)*p_yx;}void calculate_yz(){yz=yz+t*gyro[0];p_yz=p_yz+q_yz;k_yz=p_yz/(p_yz+r_yz);yz=yz+k_yz*(Ayz-yz);p_yz=(1-k_yz)*p_yz;}//---------------- Functions//Writes val to address register on ACCvoid writeTo(int DEVICE, byte address, byte val) {Wire.beginTransmission(DEVICE); //start transmission to ACCWire.write(address); // send register addressWire.write(val); // send value to writeWire.endTransmission(); //end transmission}//reads num bytes starting from address register on ACC in to buff arrayvoid readFrom(int DEVICE, byte address, int num, byte buff[]) {Wire.beginTransmission(DEVICE); //start transmission to ACCWire.write(address); //sends address to read fromWire.endTransmission(); //end transmissionWire.beginTransmission(DEVICE); //start transmission to ACCWire.requestFrom(DEVICE, num); // request 6 bytes from ACCint i = 0;while(Wire.available()) //ACC may send less than requested (abnormal){buff[i] = Wire.read(); // receive a bytei++;}Wire.endTransmission(); //end transmission}






