This is a project which I and my classmates had finished in a course focusing on practical implementation for mechatronics and system design, and is a sequel of the previous Aroma Alarm Clock project. We designed an Android app-controllable alarm clock which can heat up objects such as a water-filled container, and intend to further improve it for making coffee, so that one can enjoy a fresh cup of coffee in the morning after awakening. Similar to the previous one, I worked as the engineer in our group, and designed and constructed the hardware system.
System Framework
Fig. 1 shows the overall system architecture, which several electronic components (e.g. clock module, LCD display…) are controlled by a microcontroller that can communicate with a mobile application using a Bluetooth module. The alarm clock can be controlled either using its own hardware input (buttons) or using the mobile app. Simply put, the system has same the functions as a typical alarm clock, but has two additional features:
1. Temperature controllable heater.
2. Bluetooth communication.
Figure 1. System architecture for the coffee maker alarm.
Hardware
Arduino Uno, DS1302 chip, HC-06 and LCD1602 are used respectively for the microcontroller, real-time clock module, Bluetooth module and LCD display module. Being an end-semester project in class, the components are simply connected using a breadboard. All the hardware components except the heater are packed using patterned cardboard in a simply looking fashion (Fig. 2).
Figure 2. Hardware appearance of the coffee maker alarm.
A ceramic heater plate and temperature sensor are integrated for realizing temperature controlling (Fig. 3), and are connected out from the main hardware. The total cost for all the components is 1,741 NTD (≅ 60 USD).
Figure 3. Heater and temperature sensor.
Software
App Inventor 2 is used as the platform for creating the Android app for controlling the hardware. Fig. 4 displays the designing interface for the mobile app using the platform.
Figure 4. Design interface using App Inventor 2.
The coding section for this platform is very unique and easy to get started. It implements a block-based programming method which developers can create procedure by dragging pre-defined blocks together to for performing a certain function. Developers with no programming background can use this kind of environment for creating mobile apps. Fig. 5 shows a gallery containing the complete code for the alarm clock controlling app.
Figure 5. Gallery of block codes for the alarm clock app.
Here’s a video demonstration for using this system:
After finishing this project, I acquired important skills for system design and mechatronics integration. This enabled me to create more interesting and sophisticated projects such as the Automated Microfluidic Controlling Platform, Remote Commandable Self-Driving Toy Car and Real-time Impedance Detection Systems.