Implementation of eSticky hardware: features and components

For the eSticky project, robo.com was involved as the prototype hardware supplier. The hardware test prototype that was provided has parts that form the basis for the following technical design structure.

The previous design sketch design from Task 4.4 was taken as the basis for incorporating the hardware package into the design form.

In this article we are going to take a closer look at how the eSticky hardware implementation works and what its features are.

eSticky: the digital post-it note that helps memory

We are seven partners from four European countries-Italy, Austria, Cyprus and Poland. We brought together our design, marketing and technology skills and knowledge in the eSticky project for AAL, the European research and development program to support active and independent living.

What we did was to imagine a digital post-it note that helps older people remember their daily commitments and small appointments. A network of graphic displays assist the user by showing important information, such as:

scheduled events;
medication reminders;
nutritional recommendations.

The aim of the project is to support people with memory problems so that they maintain their independence in life.

eSticky hardware implementation: E-paper display

The E-Paper has a flat size to achieve a slim design shape for eSticky. The dimensions are shown in robo.com documents.

Display adapter

The display adapter has a connection to the e-Paper via a flat cable that can be used within a certain radius. In this way, the adapter can be placed flat and parallel to the back of the e-Paper.

This is a universal driver board for e-Paper raw panels, which can be used to drive various SPI e-Paper interfaces from Waveshare.

Features:

Standard Raspberry Pi 40PIN GPIO extension header, supports Raspberry Pi series boards, Jetson Nano;
SPI interface, for connection with other controller boards such as Raspberry/Arduino/Nucleus;
Built-in voltage translator, compatible with 3.3V/5V MCUs;
Comes with development resources and manual (examples for Raspberry Pi/Arduino/STM32).

Specifications:

Operating voltage: 3.3 V~5 V
Interface: 3-wire SPI, 4-wire SPI
Outline size: 65 mm × 30.2 mm
Mounting hole size: 3.0 mm

ESP32 microcontroller

This microcontroller can be placed on the back of the e-Paper as the display adapter.

Rechargeable Li-ion battery

With the 18650-type lithium battery, a common standard in the industry is adopted.

All 18650 batteries can be divided into types based on the cathode material. It is on this component that the basic operating characteristics of batteries depend: capacity and possible discharge current.

For the operation of lithium-ion batteries, safety requirements state that the voltage inside the batteries must be between 2.5 and 4.2 volts. However, it is particularly difficult to independently control this parameter. That is why a specially designed board with protection was invented, which prevents voltage outside the specified range.

Push button

The test button will be the basis for the technical design. It is a pressure button with physical feedback for the user.

Speaker

The speaker should emit some beeps to support the eSticky function. As known from smartphones, high quality speakers with small size are available. Power consumption is very low with few signal outputs.