单片机控制电子产品项目开发 课件 130-1-学习课件：小车行走程序开发

作者：牛俊英小车行走程序开发CONTENTS01直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA63150702舵机驱动03小车调速与转向1.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507若调转直流电源的正、负极，电机转子将会反转将直流电源的正、负极分别接到电机相对应的正、负引脚，电机转子正向转动直流有刷电机1.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507高电平时电机转动，同时电机电枢电感储存能量电枢电压平均值Uav由占空比及电源电压决定，改变占空比能够改变直流电动机的转速PWM调速控制低电平时停止向电动机提供能量1.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507H桥驱动电路使电机运转，必须导通对角线上的一对场效应管024个场效应管：左上臂、左下臂、右上臂、右下臂01当左上臂Q1管和右下臂Q4管导通时，驱动电机顺时针转动03左下臂Q2和右上臂Q3导通的情况，驱动电机逆时针转动041.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507H桥上两个同侧的场效应管不能同时导通引入开通延时死区1.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507>嵌入式芯片不能直接连至直流电机两端驱使其工作，一般使用专用驱动芯片>如L298驱动芯片，双H高电压大电流功率集成电路1.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA63150701INPUT1、INPUT2OUT1、OUT2输出的控制端，OUT1、OUT2接M01，INPUT1接高电平、INPUT2接低电平，电机M01正转，INPUT1接低电平、INPUT2接高电平，电机M01反转02INPUT3、INPUT4OUT3，OUT4输出的控制端，OUT3、OUT4接M0203En_A、En_B接控制使能端，控制电机M01和M02的停转，当两引脚接入PWM信号时，可以实现电机调速04CUR_A、CUR_B电机M01和M02的电流反馈引脚，不用时可以接地1.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507#defineIN1P00 //LN298INPUT1引脚定义#defineIN2P01 //LN298INPUT2引脚定义#defineENA P02 //LN298ENA引脚定义unsignedcharCycle=10; //电机PWM周期1.25msunsignedcharDuty=6; //电机PWM高电平时长初始值为7.5msunsignedcharCnt_PWM=0;//电机PWM计时器计数单位0.125msunsignedcharMotor_State=1;//电机状态控制变量//低两位设置方向：00停转01正转10反转//第四、五位设置占空比voidMOTOR_Ctrl(){ switch(Motor_State&0x03)//根据方向设置，调整方向设置端口

{

case0:{IN1=0;IN2=0;break;}

case1:{IN1=1;IN2=0;break;}

case2:{IN1=0;IN2=1;break;}

}

Duty=(Motor_State&0x30)>>4;//根据速度设置，调整PWM占空比

//PWM输出控制

if(Cnt_PWM<=Duty) ENA=1;

elseENA=0; }//PWM周期计时

Cnt_PWM++;

if(Cnt_PWM>=Cycle)

Cnt_PWM=0;在定时器对Cnt_PWM进行0到PWM周期Cycle循环计时MOTOR_Ctrl函数为电机控制函数按照要求的电机转动方向设置模块的IN1和IN2端口电平按照要求的电机转速设置PWM占空比参数输出PWM信号01020304按开发需要改变电机状态控制变量Motor_State，改变电机工作状态1.直流电机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA6315072.舵机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507舵机（伺服马达、servo）01从控制端输入的PWM信号能用于设定输出轴的转动角度02舵机能比较精确地控制和保持输出轴的角度。通常，这样的电机控制方式为闭环控制2.舵机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507舵机（伺服马达、servo）2.舵机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507驱动芯片直接驱动（无需隔离、驱动电流要求不高）光耦隔离的舵机电路连接//定义为全局变量或者静态变量unsignedcharCycle_Stevo=160;//舵机驱动PWM周期单位0.125ms实际时长20msunsignedcharDuty_Stevo=0;

//舵机驱动PWM信号高电平持续时间unsignedcharCnt_Stevo_PWM=0;//舵机驱动PWM信号计时器

单位0.125ms

//定时器平台，PWM计时和驱动输出Cnt_Stevo_PWM++;//舵机驱动PWM信号计时器if(Cnt_Stevo_PWM>=Cycle_Stevo)Cnt_Stevo_PWM=0;//PWM20毫秒周期计时//PWM信号输出电平控制if(Cnt_Stevo_PWM<=Duty_Stevo)

Stevo=1;elseStevo=0;2.舵机驱动e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA6315073.三轮小车调速转向e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF56865E37DAC04C7C9B262B2670CBBEB096AEE5D9F6218CBA631507左电机芯片IC4右电机芯片IC5左电机右电机小车运行状态P40P20P22P210000停停停1010正转正转向前行0110反转正转向左转0010停正转左电机为中心原地向左转1001正转反转向右转1000正转停右电机为中心原地向右转0101反转反转向后退3.三轮小车调速转向e7d195523061f1c01ef2b70529884c179423570dbaad84926380ABC1F97BAEF0C8FC051856578EAB7874501A1FFE158C4981707381814BCC4D9A8E3554438DEE4FBCF5A5B4D2A8B0989AB57E8BAC65EB4C7ADE47CB0CAEE0501E4A226B4263409BF6D490A639D9B9ED09071C131A40B4F721A3CABF