[2024 DigiKey Creative Competition] A happy old age assistant based on Raspberry Pi

sumoon_yao

[2024 DigiKey Creative Competition] A happy old age assistant based on Raspberry Pi [Copy link]

 

1. Project Introduction

1. Design name

A Raspberry Pi-based assistant for a happy old age

2. Project photos

3. Boards used in the project

1) Raspberry Pi 5

Processor: 2.4GHz quad-core 64-bit Cortex-A76

Memory: 4GB LPDDR4X-4267

Communication interface: Wi-Fi 6 (802.11ac) supports 2.4GHz and 5GHz bands

Bluetooth 5.2 supports Bluetooth low energy connections

1 x 2.5Gbps 1000M Ethernet

2 USB3.0

2 USB2.0

GPIO: Standard 40Pin GPIO plug

Audio and video interface: Dual micro HDMI interfaces, support dual 4K@60fps video output

2-lane MIPI DSI

2-lane MIPI CSI

Via HDMI and 3.5mm composite audio jack

MicroSD card slot: supports higher-speed MicroSD cards

PCIe interface: PCIe 2.0 x1 interface, supports high-speed peripheral connection

2) Accelerometer sensor module

Accelerometer, gyroscope, magnetometer

Communication interface support: I2C

3) BME680 sensor module

Support air pressure, temperature, humidity, VOC detection

Communication interface support: I2C, SPI

The plan was to buy the chip and do the board soldering myself. Considering that the BME680 chip is an LGA package, manual soldering is not very convenient, so I later purchased a BME680 sensor module on the Digi-Key website for easy testing.

4. Project Function

This project aims to use the powerful performance of Raspberry Pi 5 as the main control of this project to collect, analyze and process the data of various sensors on the front end, and then upload it to the server through WiFi. At the same time, it receives instructions or other data (audio, etc.) sent by the client (mobile phone, PC, etc.) and processes them accordingly. In this way, the living conditions of elderly people living alone can be monitored in real time, so that children or relatives can understand the current conditions of the elderly in real time, and timely warn of emergencies such as falls and take corresponding measures immediately. The living environment conditions of the elderly, such as temperature, humidity, air pressure and other data, can be understood in real time, and when necessary, the air conditioner, dehumidifier, oxygen generator, etc. can be started and stopped by manual means such as telephone or remote means.

2. System Block Diagram

1. Design ideas

The application of the Internet of Things has entered all walks of life, and this project is also one of the scenarios for the application of the Internet of Things.

MQTT (Message Queuing Telemetry Transport) is a "lightweight" communication protocol based on the publish/subscribe model. The protocol is built on the TCP/IP protocol and was released by IBM in 1999 and released as an open standard in 2013. The MQTT protocol focuses on the reliable transmission of small data packets in low-bandwidth, unstable or high-latency network environments.

The MQTT protocol has the following characteristics:

Lightweight: MQTT has low protocol overhead and is suitable for resource-constrained devices such as sensors and IoT devices.

Flexible and scalable: MQTT supports multiple transport layer protocols, such as TCP/IP, WebSocket, etc. It also provides QoS (Quality of Service) levels to ensure reliable transmission of messages.

Asynchronous communication: MQTT uses a publish/subscribe model, and there is no need for direct communication between publishers and subscribers, making system decoupling easier.

Handling low-bandwidth and high-latency networks: The MQTT protocol can reliably transmit data in environments with unstable network connections or limited bandwidth.

The overall design idea of the project is to use the powerful software functions of Raspberry Pi and its rich peripherals to complete the real-time collection, analysis and processing of various sensor data through interfaces such as I2C, and upload the data to the MQTT server through WiFi. Users can subscribe to MQTT server data through PC or mobile phone to timely understand the living status of the elderly. When necessary, they can also issue control instructions through the MQTT server to remotely turn on the air conditioner and other equipment in the elderly’s residence, or send voice messages to remind the elderly of precautions.

2. Software and hardware introduction

Hardware: Raspberry Pi 5 as the main controller, plus various sensor modules, such as air pressure, temperature and humidity sensors, accelerometer sensors, etc.

Software: The operating system uses the embedded Linux system that comes with the Raspberry Pi, which takes up less than 0.5GB of space, bringing great convenience to application development and maintenance;

The application software is mainly completed in C language. Its main functions include collecting, analyzing and processing various sensor data, and publishing the processed data to the MQTT server in a scheduled or real-time manner. At the same time, it subscribes to/receives instructions issued by the server and makes corresponding processing, such as turning on/off relays, powering on/off household appliances, or playing voice messages.

3. System Block Diagram

3. Functional description of each part

The application software is divided into 3 parts:

Master control: publishes/subscribes messages through the MQTT protocol, that is, is responsible for publishing various sensor data to the MQTT server and subscribing to messages sent by the MQTT server;

Sensor data collection: responsible for regularly collecting data from various sensors, and then analyzing and processing them before handing them over to the main control for processing;

Subscription message processing: After receiving the message sent by the MQTT server, make corresponding processing, such as turning on or off the relay.

4. Source Code

Upload later

5. Demonstration video of the work’s functions

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6. Project Summary

Through this project, I have a more intuitive understanding of the application of the Internet of Things, and also a deeper understanding of the MQTT protocol. The project itself is summarized as follows:

1. Due to time constraints, the project has only achieved partial functions. Strictly speaking, the requirements of the prototype have not been met, and further improvement will take time.

2. As for fall detection, it should belong to the category of wearable devices. It is necessary to consider battery power supply, Bluetooth low-power data transmission, etc., and the product form needs to be well planned.

3. For the main control part, for cost-sensitive products, it is also necessary to consider replacing it with a more cost-effective platform.

Jacktang

It's pretty good.

Fall detection belongs to the scope of wearable devices

An acceleration sensor is needed to detect the acceleration change of the human body in the vertical direction. When the human body falls, the acceleration sensor will detect the sudden acceleration change, thereby triggering the alarm device.