智能小车之跟随小车、避障小车原理和代码

目录

1. 红外壁障模块分析​编辑

2. 跟随小车的原理

3. 跟随小车开发和调试代码

4. 超声波模块介绍

5. 摇头测距小车开发和调试代码

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1. 红外壁障模块分析

原理和循迹是一样的，循迹红外观朝下，跟随朝前

• TCRT5000传感器的红外发射二极管不断发射红外线
• 当发射出的红外线没有被反射回来或被反射回来但强度不够大时
• 红外接收管一直处于关断状态，此时模块的输出端为高电平，指示二极管一直处于熄灭状态
• 被检测物体出现在检测范围内时，红外线被反射回来且强度足够大，红外接收管饱和
• 此时模块的输出端为低电平，指示二极管被点亮
• 总结就是一句话，没反射回来，D0输出高电平，灭灯

2. 跟随小车的原理

• 左边跟随模块能返回红外，输出低电平，右边不能返回，输出高电平，说明物体在左边，需要左转
• 右边跟随模块能返回红外，输出低电平，左边不能返回，输出高电平，说明物体在右边，需要右转

3. 跟随小车开发和调试代码

//main.c
#include "motor.h"
#include "delay.h"
#include "reg52.h"//sbit leftSensor = P2^7;
//sbit rightSensor = P2^6;sbit leftSensor = P2^5;
sbit rightSensor = P2^4;void main()
{while(1){if(leftSensor == 0 && rightSensor == 0){goForward();}if(leftSensor == 1 && rightSensor == 0){goRight();}if(leftSensor == 0 && rightSensor == 1){goLeft();}if(leftSensor == 1 && rightSensor == 1){//停stop();}}
}//motor.c
#include "reg52.h"sbit RightCon1A = P3^2;
sbit RightCon1B = P3^3;sbit LeftCon1A = P3^4;
sbit LeftCon1B = P3^5;void goForward()
{LeftCon1A = 0;LeftCon1B = 1;RightCon1A = 0;RightCon1B = 1;
}void goRight()
{LeftCon1A = 0;LeftCon1B = 1;RightCon1A = 0;RightCon1B = 0;
}void goLeft()
{LeftCon1A = 0;LeftCon1B = 0;RightCon1A = 0;RightCon1B = 1;
}void goBack()
{LeftCon1A = 1;LeftCon1B = 0;RightCon1A = 1;RightCon1B = 0;
}void stop()
{LeftCon1A = 0;LeftCon1B = 0;RightCon1A = 0;RightCon1B = 0;
}//delay.c#include "intrins.h"void Delay1000ms()		//@11.0592MHz
{unsigned char i, j, k;_nop_();i = 8;j = 1;k = 243;do{do{while (--k);} while (--j);} while (--i);
}

4. 超声波模块介绍

使用超声波模块，型号：HC-SR04

• 怎么让它发送波 Trig ，给Trig端口至少10us的高电平
• 怎么知道它开始发了 Echo信号，由低电平跳转到高电平，表示开始发送波
• 怎么知道接收了返回波 Echo，由高电平跳转回低电平，表示波回来了
• 怎么算时间 Echo引脚维持高电平的时间！ 波发出去的那一下，开始启动定时器 波回来的拿一下，我们开始停止定时器，计算出中间经过多少时间
• 怎么算距离 距离 = 速度 （340m/s）* 时间/2

时序图：

5. 摇头测距小车开发和调试代码

//main.c
#include "reg52.h"
#include "hc04.h"
#include "delay.h"
#include "sg90.h"
#include "motor.h"#define MIDDLE 0
#define LEFT 1
#define RIGHT 2void main()
{char dir;double disMiddle;double disLeft;double disRight;Time0Init();Time1Init();//舵机的初始位置sgMiddle();Delay300ms();Delay300ms();dir = MIDDLE;while(1){if(dir != MIDDLE){sgMiddle();dir = MIDDLE;Delay300ms();}disMiddle = get_distance();if(disMiddle > 35){//前进goForward();}else if(disMiddle < 10){goBack();}else{//停止stop();//测左边距离sgLeft();Delay300ms();disLeft = get_distance();sgMiddle();Delay300ms();sgRight();dir = RIGHT;Delay300ms();disRight = get_distance();if(disLeft < disRight){goRight();Delay150ms();stop();}if(disRight < disLeft){goLeft();Delay150ms();stop();}}}
}//hc04.c
#include "reg52.h"
#include "delay.h"sbit Trig     = P2^3;
sbit Echo     = P2^2;void Time1Init()
{	TMOD &= 0x0F;		//设置定时器模式TMOD |= 0x10;TH1 = 0;TL1 = 0;//设置定时器0工作模式1，初始值设定0开始数数，不着急启动定时器
}void startHC()
{Trig = 0;Trig = 1;Delay10us();Trig = 0;
}double get_distance()
{double time;//定时器数据清零，以便下一次测距TH1 = 0;TL1 = 0;//1. Trig ，给Trig端口至少10us的高电平startHC();//2. echo由低电平跳转到高电平，表示开始发送波while(Echo == 0);//波发出去的那一下，开始启动定时器TR1 = 1;//3. 由高电平跳转回低电平，表示波回来了while(Echo == 1);//波回来的那一下，我们开始停止定时器TR1 = 0;//4. 计算出中间经过多少时间time = (TH1 * 256 + TL1)*1.085;//us为单位//5. 距离 = 速度 （340m/s）* 时间/2return  (time * 0.017);
}//delay.c
#include "intrins.h"void Delay2000ms()		//@11.0592MHz
{unsigned char i, j, k;i = 15;j = 2;k = 235;do{do{while (--k);} while (--j);} while (--i);
}void Delay10us()		//@11.0592MHz
{unsigned char i;i = 2;while (--i);
}void Delay300ms()		//@11.0592MHz
{unsigned char i, j, k;_nop_();i = 3;j = 26;k = 223;do{do{while (--k);} while (--j);} while (--i);
}void Delay150ms()		//@11.0592MHz
{unsigned char i, j, k;i = 2;j = 13;k = 237;do{do{while (--k);} while (--j);} while (--i);
}void Delay450ms()		//@11.0592MHz
{unsigned char i, j, k;_nop_();i = 4;j = 39;k = 209;do{do{while (--k);} while (--j);} while (--i);
}//sg90.c
#include "reg52.h"
#include "delay.h"sbit sg90_con = P1^1;int jd;
int cnt = 0;void Time0Init()
{//1. 配置定时器0工作模式位16位计时TMOD &= 0xF0;		//设置定时器模式TMOD |= 0x01;//2. 给初值，定一个0.5出来TL0=0x33;TH0=0xFE;//3. 开始计时TR0 = 1;TF0 = 0;//4. 打开定时器0中断ET0 = 1;//5. 打开总中断EAEA = 1;
}void sgMiddle()
{//中间位置jd = 3; //90度 1.5ms高电平cnt = 0;
}void sgLeft()
{//左边位置jd = 5; //135度 1.5ms高电平cnt = 0;
}void sgRight()
{//右边位置jd = 1; //0度cnt = 0;
}void Time0Handler() interrupt 1
{cnt++;  //统计爆表的次数. cnt=1的时候，报表了1//重新给初值TL0=0x33;TH0=0xFE;//控制PWM波if(cnt < jd){sg90_con = 1;}else{sg90_con = 0;}if(cnt == 40){//爆表40次，经过了20mscnt = 0;  //当100次表示1s，重新让cnt从0开始，计算下一次的1ssg90_con = 1;}}//motor.c
#include "reg52.h"sbit RightCon1A = P3^2;
sbit RightCon1B = P3^3;sbit LeftCon1A = P3^4;
sbit LeftCon1B = P3^5;void goForward()
{LeftCon1A = 0;LeftCon1B = 1;RightCon1A = 0;RightCon1B = 1;
}void goRight()
{LeftCon1A = 0;LeftCon1B = 1;RightCon1A = 0;RightCon1B = 0;
}void goLeft()
{LeftCon1A = 0;LeftCon1B = 0;RightCon1A = 0;RightCon1B = 1;
}void goBack()
{LeftCon1A = 1;LeftCon1B = 0;RightCon1A = 1;RightCon1B = 0;
}void stop()
{LeftCon1A = 0;LeftCon1B = 0;RightCon1A = 0;RightCon1B = 0;
}