项目5

智 能 安 防







项目5


本项目通过鸿蒙App控制Hi3861开发板，连接HCSR04超声波传感器，实现智能安防系统。

5.1总体设计

本部分包括系统架构和系统流程。

5.1.1系统架构

系统架构如图51所示，Hi3861开发板与外设引脚连线如表51所示。 




图51系统架构




表51Hi3861开发板与外设引脚连线


Hi3861开发板HCSR04超声波光敏传感器蜂鸣器OLED串口屏


5VVCCVCCVCCVCC
GNDGNDGNDGNDGND
GPIO11Trig///
GPIO12Echo///
GPIO10/DO//
GPIO5//I/O/
GPIO13///SCL
GPIO14///SDA
板载LED///


5.1.2系统流程

系统流程如图52所示。





图52系统流程


5.2模块介绍

本项目由VSCode和DevEco Studio开发，包括超声波测距、光敏感知、蜂鸣器控制、OLED显示、WiFi模块、OneNET云平台和前端模块。下面分别给出各模块的功能介绍及相关代码。

5.2.1超声波测距

该模块主要利用超声波模块进行测距，将GPIO11设置为输出，每个周期给Trig引脚发送20~50μs的脉冲，激发超声波模块发出8组超声波，当接收到返回信号时，Echo产生相应的高电平脉冲，脉冲的宽度、声波与返回时间有关，之后便可以计算距离，相关代码如下:

float GetDistance(void)

{

static unsigned long start_time = 0, time = 0;

float distance = 0.0;

IotGpioValue value = IOT_GPIO_VALUE0;

unsigned int flag = 0;

//超声波传感器Trig为GPIO11，Echo为GPIO12

IoTGpioSetDir(HI_IO_NAME_GPIO_12, IOT_GPIO_DIR_IN);

IoTGpioSetDir(HI_IO_NAME_GPIO_11, IOT_GPIO_DIR_OUT);

//触发Trig

IoTGpioSetOutputVal(HI_IO_NAME_GPIO_11, IOT_GPIO_VALUE1);

hi_udelay(20);

IoTGpioSetOutputVal(HI_IO_NAME_GPIO_11, IOT_GPIO_VALUE0);

//检测Echo高电平时间

while (1) {

IoTGpioGetInputVal(HI_IO_NAME_GPIO_12, &value);

if ( value == IOT_GPIO_VALUE1 && flag == 0) {

start_time = hi_get_us();

flag = 1;

}

if (value == IOT_GPIO_VALUE0 && flag == 1) {

time = hi_get_us() -start_time;

start_time = 0;

break;

}

}

//计算距离

distance = time * 0.034 / 2;

printf("［Distance］:%f.＼r＼n",distance);

return distance;

}


5.2.2光敏感知

通过光敏电阻感知外界光强，当外界光强低于某个阈值时，则传感器的DO口会给出一个高电平，根据是否接收到高电平判断板载LED亮灭。

#define LED_TEST_GPIO 9//使用hispark_pegasus开发板

void GetLight(void)

{

IotGpioValue value = IOT_GPIO_VALUE0;

//初始化LED的GPIO

IoTGpioInit(LED_TEST_GPIO);

//设置为输入/输出

IoTGpioSetDir(LED_TEST_GPIO, IOT_GPIO_DIR_OUT);

//设置光敏传感器的DO口

IoTGpioSetDir(HI_IO_NAME_GPIO_10, IOT_GPIO_DIR_IN);

if(led_flag==2){

IoTGpioSetDir(LED_TEST_GPIO, 1); //LED亮

}

else{

IoTGpioGetInputVal(HI_IO_NAME_GPIO_10, &value);

if ( value == IOT_GPIO_VALUE1 ) {

IoTGpioSetDir(LED_TEST_GPIO, 1); //LED亮

led_flag = 1;

printf("on＼n");

}

if (value == IOT_GPIO_VALUE0 ) {

IoTGpioSetDir(LED_TEST_GPIO, 0); //LED灭

led_flag = 0;

printf("off＼n");

}

}

}


5.2.3蜂鸣器控制

通过简单的高低电平控制声响。

void BeepRing(void)

{

//初始化GPIO

IoTGpioInit(HI_IO_NAME_GPIO_5);

//设置为输出

IoTGpioSetDir(HI_IO_NAME_GPIO_5, IOT_GPIO_DIR_OUT);

//GPIO复用

hi_io_set_func(HI_IO_NAME_GPIO_5,HI_IO_FUNC_GPIO_5_GPIO);

//输出低电平

IoTGpioSetOutputVal(HI_IO_NAME_GPIO_5,0);

beep_flag=0;

printf("BeepRing＼n");

}

void BeepStop(void)

{

//初始化GPIO

IoTGpioInit(HI_IO_NAME_GPIO_5);

//设置为输出

IoTGpioSetDir(HI_IO_NAME_GPIO_5, IOT_GPIO_DIR_OUT);

//GPIO复用

hi_io_set_func(HI_IO_NAME_GPIO_5,HI_IO_FUNC_GPIO_5_GPIO);

//输出高电平

IoTGpioSetOutputVal(HI_IO_NAME_GPIO_5,1);

beep_flag=1;

printf("BeepStop＼n");

}


5.2.4OLED显示

SSD1306逻辑功能代码如下:

void OLED(void)

{

IoTGpioInit(HI_IO_NAME_GPIO_13);

IoTGpioInit(HI_IO_NAME_GPIO_14);

hi_io_set_func(HI_IO_NAME_GPIO_13, HI_IO_FUNC_GPIO_13_I2C0_SDA);

hi_io_set_func(HI_IO_NAME_GPIO_14, HI_IO_FUNC_GPIO_14_I2C0_SCL);

IoTI2cInit(0, OLED_I2C_BAUDRATE);

usleep(20*1000);

ssd1306_Init();

ssd1306_Fill(Black);

ssd1306_SetCursor(0, 0);

if(distance_flag==0){

ssd1306_DrawString("Be Carefully!", Font_11x18, White);

ssd1306_UpdateScreen();

printf("test1");

}

else{

ssd1306_DrawString("Safe", Font_11x18, White);

ssd1306_UpdateScreen();

printf("test2");

}



}


5.2.5WiFi模块

WiFi连接相关代码如下:

void wifi_wpa_event_cb(const hi_wifi_event *hisi_event)

{

if (hisi_event == NULL)

return;

switch (hisi_event->event) {

case HI_WIFI_EVT_SCAN_DONE:

printf("WiFi: Scan results available＼n");

break;

case HI_WIFI_EVT_CONNECTED:

printf("WiFi: Connected＼n");

netifapi_dhcp_start(g_lwip_netif);

wifi_ok_flg = 1;

break;

case HI_WIFI_EVT_DISCONNECTED:

printf("WiFi: Disconnected＼n");

netifapi_dhcp_stop(g_lwip_netif);

hi_sta_reset_addr(g_lwip_netif);

break;

case HI_WIFI_EVT_WPS_TIMEOUT:

printf("WiFi: wps is timeout＼n");

break;

default:

break;

}

}

int hi_wifi_start_connect(void)

{

int ret;

errno_t rc;

hi_wifi_assoc_request assoc_req = {0}

rc = memcpy_s(assoc_req.ssid, HI_WIFI_MAX_SSID_LEN + 1, "OCF24", 8);

if (rc != EOK) {

return -1;

}

//热点加密方式

assoc_req.auth = HI_WIFI_SECURITY_WPA2PSK;

//热点密码 

memcpy(assoc_req.key, "xxxxxxxx", 8);

ret = hi_wifi_sta_connect(&assoc_req);

if (ret != HISI_OK) {

return -1;

}

return 0;

}

int hi_wifi_start_sta(void)

{

int ret;

char ifname［WIFI_IFNAME_MAX_SIZE + 1］ = {0};

int len = sizeof(ifname);

const unsigned char wifi_vap_res_num = APP_INIT_VAP_NUM;

const unsigned char wifi_user_res_num = APP_INIT_USR_NUM;

unsigned intnum = WIFI_SCAN_AP_LIMIT;

ret = hi_wifi_sta_start(ifname, &len);

if (ret != HISI_OK) {

return -1;

}

ret = hi_wifi_register_event_callback(wifi_wpa_event_cb);

if (ret != HISI_OK) {

printf("register wifi event callback failed＼n");

}

g_lwip_netif = netifapi_netif_find(ifname);

if (g_lwip_netif == NULL) {

printf("%s: get netif failed＼n", __FUNCTION__);

return -1;

}

//开始扫描附近的WiFi热点 

ret = hi_wifi_sta_scan();

if (ret != HISI_OK) {

return -1;

}

sleep(5); 

hi_wifi_ap_info *pst_results = malloc(sizeof(hi_wifi_ap_info) * WIFI_SCAN_AP_LIMIT);

if (pst_results == NULL) {

return -1;

}

//将扫描到的热点结果进行存储

ret = hi_wifi_sta_scan_results(pst_results, &num);

if (ret != HISI_OK) {

free(pst_results);

return -1;

}

//打印扫描到的所有热点

for (unsigned int loop = 0; (loop < num) && (loop < WIFI_SCAN_AP_LIMIT); loop++) {

printf("SSID: %s＼n", pst_results［loop］.ssid);

}

free(pst_results);

//开始接入热点 

ret = hi_wifi_start_connect();

if (ret != 0) {

return -1;

}

return 0;

}

void wifi_sta_task(void *arg)

{

arg = arg;

//连接热点

hi_wifi_start_sta();

while(wifi_ok_flg == 0)

{

usleep(30000);

}

usleep(2000000);


5.2.6OneNET云平台

本部分包括创建账号、创建产品、添加设备和相关代码。

1. 创建账号

登录网页https：//open.iot.10086.cn/passport/reg/，按要求填写注册信息后进行实名认证。


2. 创建产品

进入Studio平台后，在全部产品服务中选择多协议接入。 单击“添加产品”按钮，在弹出页面中按照提示填写产品信息。本项目采用MQTT协议接入，如图53所示。




图53创建产品


3. 添加设备

单击“设备管理”，选择“添加设备”，按照提示填写相关信息，如图54所示。




图54添加设备


4. 相关代码

下面给出实现连接OneNET云平台及整个系统的逻辑控制代码。

void onenet_cmd_rsp_cb(uint8_t *recv_data, size_t recv_size, uint8_t **resp_data, size_t *resp_size)

{

printf("recv data is %.*s＼n", recv_size, recv_data);

strcpy(temp1, (char *)(recv_data)); //暂存recv data

int messageCode = (temp1［2］ - '0') ;

printf("messageCode is %d＼n", messageCode);

if(messageCode==0){

BeepStop();

printf("Beep＼n");

}

if(messageCode==1){

IoTGpioSetDir(LED_TEST_GPIO, 1); //LED亮

led_flag = 2;

printf("LED ON＼n");

}

if(messageCode==2){

IoTGpioSetDir(LED_TEST_GPIO, 1); //LED灭

led_flag = 0;

printf("LED OFF＼n");

}

*resp_data = NULL;

*resp_size = 0;

}

int onenet_test(void)

{

device_info_init(ONENET_INFO_DEVID, ONENET_INFO_PROID, ONENET_INFO_AUTH, ONENET_INFO_APIKEY, ONENET_MASTER_APIKEY);

onenet_mqtt_init();

onenet_set_cmd_rsp_cb(onenet_cmd_rsp_cb);

IoTWatchDogDisable();

while (1)

{

GetLight();

temp = GetDistance();

OLED();

//连续判断，防止错判

if(temp<3){

count++;

}

else{

count=0;

}

if(temp<3&&count>3){

BeepRing(); //蜂鸣器响

printf("［Beep］:%d.＼r＼n",beep_flag);

distance_flag=0;

printf("［person］:%d.＼r＼n",distance_flag);

}

else{

BeepStop(); //蜂鸣器不响

printf("［person］:%d.＼r＼n",distance_flag);

distance_flag=1;

}

//上传至OneNET

if (onenet_mqtt_upload_digit("person", distance_flag) < 0)

{

printf("upload has an error, stop uploading");

//break;

}

else

{

printf("buffer : {＼"person＼":%d} ＼r＼n", distance_flag);

} 

sleep(1);

}

return 0;

}


5.2.7前端模块

本部分包括界面设计和发送POST请求。

1. 界面设计

<?xml version="1.0" encoding="utf-8"?>

<DirectionalLayout

xmlns:ohos="http://schemas.huawei.com/res/ohos"

ohos:height="match_parent"

ohos:width="match_parent"

ohos:alignment="horizontal_center"

ohos:orientation="vertical">

<Text

ohos:id="$+id:text_type_get"

ohos:height="60vp"

ohos:width="match_parent"

ohos:text_alignment="center"

ohos:layout_alignment="horizontal_center"

ohos:text="GET请求"

ohos:text_size="30vp"

/>

<Text

ohos:id="$+id:text_type_post"

ohos:height="60vp"

ohos:text_alignment="center"

ohos:width="match_parent"

ohos:background_element="#ed6262"

ohos:layout_alignment="horizontal_center"

ohos:text="POST请求"

ohos:text_size="30vp"

/>

<ScrollView

ohos:height="match_parent"

ohos:width="match_parent"

>

<DirectionalLayout

ohos:height="match_parent"

ohos:width="match_parent">

<Text

ohos:id="$+id:text_result"

ohos:height="match_parent"

ohos:multiple_lines="true"

ohos:text_alignment="center"

ohos:width="match_parent"

ohos:layout_alignment="horizontal_center"

ohos:text="显示结果"

ohos:text_size="20vp"

/>

</DirectionalLayout>

</ScrollView>

</DirectionalLayout> 


2. 发送POST请求

package com.example.afinal.slice;

import com.example.afinal.ResourceTable;

import ohos.aafwk.ability.AbilitySlice;

import ohos.aafwk.content.Intent;

import ohos.agp.components.Component;

import ohos.agp.components.Text;

import okhttp3.*;

import java.io.IOException;

public class MainAbilitySlice extends AbilitySlice {

//private static AbilityForm textResult;

Text TextGet, TextPost, textResult;

private boolean status;

final String cloud_url =

"http://api.heclouds.com/cmds?device_id=962845387";

@Override

public void onStart(Intent intent) {

super.onStart(intent);

super.setUIContent(ResourceTable.Layout_ability_main);

TextGet = findComponentById(ResourceTable.Id_text_type_get);

TextPost = findComponentById(ResourceTable.Id_text_type_post);

textResult = findComponentById(ResourceTable.Id_text_result);

TextGet.setClickedListener(new Component.ClickedListener() {

@Override

public void onClick(Component component) {

OkHttpClient client = new OkHttpClient();

Request.Builder requestBuilder = new Request.Builder();

requestBuilder.addHeader("api-key","CT0J7NvniU4E5hsdH4emD=FzKs0=");

HttpUrl.Builder urlBuilder = HttpUrl.parse("http://api.heclouds.com/devices/962845387/datapoints").newBuilder(); //todo接口链接

urlBuilder.addQueryParameter("datastream_id", "temperature");

 //参数

urlBuilder.addQueryParameter("limit","4"); //密钥

requestBuilder.url(urlBuilder.build());

Call call = client.newCall(requestBuilder.build());

call.enqueue(new Callback() {

@Override

public void onFailure(Call call, IOException e) {

//todo失败回调需要回到主线程显示结果

getUITaskDispatcher().asyncDispatch(new Runnable() 

{

@Override

public void run() {

textResult.setText(e.getMessage());

}

});

}

@Override

public void onResponse(Call call, Response response) throws IOException {

if (response.isSuccessful()) {

String result = response.body().string();

//处理界面需要切换到界面线程处理

getUITaskDispatcher().asyncDispatch(new Runnable() {

@Override

public void run() {

textResult.setText(result);

}

});

}

}

});

}

});

TextPost.setClickedListener(new Component.ClickedListener() {

@Override

public void onClick(Component component) {

textResult.setText("post can be pressed");

OkHttpClient client = new OkHttpClient();

FormBody body = new FormBody.Builder()

.add("temperature", "77")//日期参数

.build();


Request request = new Request.Builder()

.header("api-key", "CT0J7NvniU4E5hsdH4emD=FzKs0=")

.url("http://api.heclouds.com/cmds?device_id=962845387")

.post(body)

.build();

Call call = client.newCall(request);

call.enqueue(new Callback() {

@Override

public void onFailure(Call call, IOException e) {

//失败回调需要回到主线程显示结果

getUITaskDispatcher().asyncDispatch(new Runnable() 

{

@Override

public void run() {

textResult.setText(e.getMessage());

}

});

}

@Override

public void onResponse(Call call, Response response) throws IOException {

if (response.isSuccessful()) {

String result = response.body().string();

//处理界面需要切换到界面线程处理

//失败回调需要回到主线程显示结果

getUITaskDispatcher().asyncDispatch(new Runnable() {

@Override

public void run() {

textResult.setText(result);

}

});

}

}

});

}

});

}


5.3产品展示

Hi3861开发板的实现效果如图55所示，串口监视器效果如图56所示，鸿蒙App的实现效果如图57所示。




图55Hi3861开发板实现效果





图56串口监视器效果





图57App页面效果


5.4元件清单

完成本项目所需的元件及数量如表52所示。



表52元件清单


元件/测试仪表数量元件/测试仪表数量


面包板1个光敏模块1个
Hi38611个蜂鸣器1个
HCSR04超声波传感器1个OLED串口屏1个