🏭 HarmonyOS Practical Practice: Create a “Classic Eye” distributed monitoring system for industrial equipment

This content originally appeared on DEV Community and was authored by lyc233333

As a developer who has debugged equipment in the factory until the early morning, today I want to share the actual combat of HarmonyOS in industrial monitoring!When I was using distributed management for equipment monitoring, my master praised it as “three times faster than traditional systems”. Come and take a look at these useful things~

1. The “life and death demand” of industrial monitoring

Last year, when I helped the workshop change the monitoring system, the master patted the machine and said:

• Second alarm: The motor temperature exceeds 80℃ and you must stop immediately. If you slow down for 1 second, the equipment may be burned
• Discontinued transmission: Workshop WiFi is occasionally stuck, data cannot be lost
• Permission Layer: Workers can only view data, engineers can adjust parameters

HarmonyOS’s distributed service is just enough to use, such as installing “intercom + recorder” on each device, and data can be stored when sending messages in real time~

2. System architecture: Assign “job types” to the equipment

1. The three-layer architecture is super clear

2. Only when the communication plan is selected correctly can it be stable

• Multicast transmission: Like workshop broadcast, the motor temperature exceeds the threshold, all workshop equipment knows
• HTTP long connection: Like private chat with walkie-talkie, engineers use it when remotely adjusting parameters

3. Core function implementation: from monitoring to control

1. Equipment Discovery: “Wear a Working Card” for each machine

import { mdns } from '@kit.NetworkKit';

// Create equipment scanners, like security guards to check industrial license plates
let scanner = mdns.createDiscoveryService(this.context, '_industry_monitor._tcp');

// Record the information on the work card when discovering the equipment
scanner.on('serviceFound', (device) => {
console.log(`Finding device: ${device.serviceName}, IP: ${device.hostName}`);
// Save the device IP to the "roster"
});

// Start patrol and check equipment
scanner.startSearchingMDNS();

2. Data collection: Regularly record data for the device “install diary”

import { http } from '@kit.NetworkKit';

// Receive data regularly, like collecting workshop daily reports
function collects data() {
    http.request(
'http://central control room IP:8080/data',
        {
            method: 'POST',
            extraData: JSON.stringify({ 
Motor temperature: 65.2,
Current: 2.3,
Running status: 'Normal'
            })
        },
        (err, data) => {
            if (!err) {
console.log('Data has been reported to the central control room');
            } else {
console.log('Report failed, save the local diary first');
// Save local cache and wait until the network is ready before sending
            }
        }
    );
}

// Receive every 30 seconds
setInterval(receive data, 30000);

3. Remote Control: Engineer’s “Remote Wrench”

// Engineer adjusts the motor speed
function speed adjustment (device IP, new speed) {
    http.request(
`http://${device IP}:8080/control`,
        {
            method: 'POST',
            extraData: JSON.stringify({ 
Command: 'Replace the speed',
Parameters: New speed
            })
        },
        (err, data) => {
            if (!err) {
console.log(`The device has been adjusted to ${new speed}r/min`);
            } else {
console.error('Change speed failed, check permission');
            }
        }
    );
}

4. Industrial-grade optimization: pitfalls that have been stepped on in the workshop

• The disconnected network continues to spread: There are many metals in the workshop, and WiFi is occasionally interrupted?
  Solution: First store the data locally in the device, check the network every 5 minutes, and send it in batches after it is connected, like saving enough daily reports before submitting

• Permission Layer: Worker accidentally touched the shutdown button?
  Solution: Three levels of permissions—
  Worker: Only view data
  Engineer: Can adjust parameters
  Administrator: Only shut down

• Data encryption: Are you afraid that the workshop data will be stolen?
  Solution: Use AES to encrypt the data during transmission, such as wearing a bulletproof vest for the data, and then decrypt it when the central control room receives it.

5. The last thought

Now this system has been running in the workshop for half a year. The most exciting thing is that the motor bearing is about to burn. The system called the alarm 10 seconds in advance, saving the money of a motor~ But I remember that during the first debugging, the inverter parameters were adjusted incorrectly, and the motor suddenly accelerated and scared the master

This content originally appeared on DEV Community and was authored by lyc233333