Smart Echo

Abstract

The primary aim of this course project entails the development of an embedded system to process fundamental voice commands locally without reliance on the internet, thereby enabling the control of smart home devices via Bluetooth connectivity. The proposed system features a central controller tasked with overseeing various home appliances, including power outlets, temperature sensors, lighting systems, security apparatus, and emergency systems, all of which can be seamlessly operated through voice commands. Since the internet and cloud services are not required for an offline system, it can perform its essential functions while ensuring protection against cyber-attacks, providing privacy, and quicker responses.

Given the system’s offline operational mode, adopting Bluetooth Low Energy (BLE) technology instead of the high peak current consumption associated with traditional Wi-Fi-based systems represents an energy-efficient choice.

Product Features

The proposed product has two types of devices, one for recognizing voice commands (Central) and the other for sensing the environment or controlling appliances (Edge).
The device is designed to operate offline without an Internet connection.
The Central Node provides accurate and reliable voice recognition technology for processing voice commands on-board.
The Central Node seamlessly connects and controls a wide range of smart home devices: Edge Nodes with Bluetooth connectivity.
Edge Node runs on the battery, harvests energy from surroundings, and lasts months without battery replacement.
Edge Nodes are robust and have a portable physical design that suits home automation applications for controlling smart appliances.

Block Diagram

Proposed System mainly consists of 2 modules, the Central/Main Node with Power conditioning and the Edge Node with energy harvesting.
Central Node is always active and is in listening mode; hence, it requires continuous supply from mains. This node connects with edge nodes to control/monitor via BLE.
Edge nodes are power efficient, run on battery for months, and actively harvest energy from the environment. These nodes can either control an appliance or monitor the environment via sensors.
A bistable relay is used to control switching action of a home appliances.
Integrated rotary encoder to control the temperature setting of a room.
Memory LCD is used to display the live temperature and the temperature settings.