为什么我在超声波环境中得到这个错误?

Question

我已经从超声波安装了多个库，我安装的最后一个是"ultrasonic-master library"。这是图书馆的问题吗?

我有这个代码使用超声波传感器，但我得到'unsigned int ultrasonic::timing()'在这个上下文中是私有的

我能试着解决这个问题吗?如有任何帮助，不胜感激。

#include <Ultrasonic.h> 

const int IN4 = 6;  
const int IN3 = 7;  
const int IN2 = 5; 
const int IN1 = 4;  
const int ENA = 3; 
const int ENB = 2; 

const int echoPin = 8;  //digtal pin used for HC-SR04 ECHO in order to receive the signal
const int trigPin = 9;  //digtal pin used for HC-SR04 ECHO in order to send the signal
Ultrasonic ultrasonic(trigPin, echoPin);  //initializing the arduino pins
int distance;  
String result;  

int velocity = 0;
//on or off
boolean go = true;
float dist_cm = distance;

void setup() {
pinMode(echoPin, INPUT);   
pinMode(trigPin, OUTPUT);  
pinMode(IN4, OUTPUT);     
pinMode(IN3, OUTPUT);    
pinMode(IN2, OUTPUT);      
pinMode(IN1, OUTPUT);      
pinMode(ENA, OUTPUT);     
pinMode(ENB, OUTPUT);     
analogWrite(ENA, 145);  
analogWrite(ENB, 145);  
}
void loop() {  
float distance = cmMsec();  
dist_cm = distance;
if (dist_cm <= 10) {
decisao();
}
delay(100);
}
float cmMsec() {

float cmMsec;
long microsec = ultrasonic.timing();                    
cmMsec = ultrasonic.convert(microsec, Ultrasonic::CM);  
return (cmMsec);                                        
delay(10);
}
void go_forward()  
{
digitalWrite(IN1, HIGH);
digitalWrite(IN2, LOW);
digitalWrite(IN3, HIGH);
digitalWrite(IN4, LOW);
analogWrite(ENA, velocity);
analogWrite(ENB, velocity);
}
void freio() {  
digitalWrite(IN4, LOW);
digitalWrite(IN3, LOW);
digitalWrite(IN2, LOW);
digitalWrite(IN1, LOW);
analogWrite(ENA, velocity);
analogWrite(ENB, velocity);
}
void decisao() {
// this block is responsible for change the speed of the car when the distance goes UP
if (go == true) {
if (distance > 30) {
while (velocity < 120) {
go_forward();
velocity = velocity + 10;
delay(50);
}
}
if (velocity >= 120) {
while (distance >= 60 && distance <= 70) {
siga_em_frente();
velocity = velocity + 10;
delay(50);
}
}
if (distance < 70) {
while (velocity < 145) {
go_forward();
velocity = velocity + 10;
delay(50);
}
}
if (velocity >= 145) {
while (distance >= 90 && distance <= 100) {
go_forward();
velocity = velocity + 10;
delay(50);
}
}
if (distance < 100) {
while (velocity < 220) {
go_forward();
velocity = velocity + 10;
delay(50);
}
}
}
delay(10000);
// this block is responsible for change the speed of the car when the distance goes UP
if (go == true) {
if (distance >= 90 && distance <= 100) {  
while (velocity <= 145) {               
go_forward();
velocity = velocity - 10;
delay(50);
}
}
if (velocity > 140 && velocity <= 145) {    
while (distance >= 70 && velocity <= 60) {  
go_forward();
velocity = velocity - 10;
delay(50);
}
}
if (distance <= 60 && velocity <= 30) {  
while (velocity <= 120) {
go_forward();
velocity = velocity - 10;
delay(50);
}
}
if (velocity > 110 && velocity <= 120) {
while (distance < 30) {
velocity = velocity - 10;
delay(50);
}
}
if (distance < 30) {
if (velocity > 5 && velocity <= 0) {
go = !go; 
}
}
}
if (go == true) {
break();
}
}

Answer 1

unsigned int Ultrasonic::timing()

是一个私有方法。在超声波类中，该方法被声明为私有。这意味着它只能被超声波类本身调用。它不打算供您使用

为了使用它，它必须是公共的。所以你需要编辑这个类。