Week 15 - System Integration
INDIVIDUAL ASSIGNMENT
• Design and document the system integration for your final project
Overview
This week’s assignment is to document the system integration for my Final Project. The first thing I need is a System Diagram that will provide an idea of the different systems and components required to realize my Final Project. As shown in my System Diagram above, my Final Project has the following sections:
ON PRODUCT - 5V SYSTEM
• Clock Display
• Sound
• Control Centre
ON PRODUCT - 12V SYSTEM
• Power
• Motion Control
MOBILE DEVICE
• Time/Alarm Setting Controls
I also need to have sections for other things such as:
• Structure/Housing
• Assembly and Integration
SYSTEM INTEGRATION
Here, I document the development for different sections of my Final Project in detail.
For a week-by-week chronological update on general progress and development, please visit my Final Project page here.
ON PRODUCT - 5V SYSTEM
Clock Display
I had previously explored making a 7-segment display in Week 10 as shown in the video below.
My experience making this 7-segment prototype revealed some challenges that I will need to address for the Final Project. These are:
- The wires connecting the LED strips between segments are difficult to solder. There are many of them and even if done successfully, it sometimes looks messy, especially around corners.
- Compared to the prototype digit, the digit has to be smaller as I will need to place 4 of them on the project (on one of the roof slopes).
With these in mind, I have currently purchased LED strips with LEDS that are closer to each other. I have also used connectors on some of the corners to reduce the amount of soldering required.
I would also like to introduce an RTC module to the Clock Display so that it is able to keep time even when disconnected from the power supply.
UPDATE: 19 May 2025 – TOO BIG
I tried constructing a single digit to test with my components and it turns out that the off-the-shelf connectors end up adding a lot of size to the digit. A single digit in this configuration means that I can only put 2 digits on the entire clock display panel. I need to fit 4 digits on the clock display panel.
At this point, in my quest to make the digit smaller, I am wondering if I should abandon the idea of using off-the-shelf connectors. I found a compromise which I retain some of the parts but discard the connectors. I will then solder at those connections.
I put this new configuration onto a 3D printed holder and make four of these holders to get a feel of the final size of the clock display panel. This is probably the smallest size I can achieve but it is still about 25% too large compared to my current 3D printed prototype. However, I think I can still get this project to work with some modifications.
UPDATE: 20 May 2025 – ONE DIGIT
Today, I tried soldering one digit and getting it to work. I succeeded after much frustration and perseverance.
Soldering the LEDs together is certainly easier with the off-the-shelf connectors, but there are still many points to solder. Initially, I tried to rush it, and it did not work out well at all. There were breaks in continuity that were not so easy to rectify. I started again and this time I took it step by step. I checked the continuity after each section to ensure that everything was soldered properly.
UPDATE: 21to 23 May 2025 – FOUR DIGITS COMPLETE
After a few days of work, I completed all four digits as shown in the video below.
Each digit was constructed of:
1. A bottom holder for the Neopixel LEDs
2. A diffuser cover on top
I sketched out the dimensions of each part, created the sketches and 3D models in Fusion 360, and then exported the STLs to be 3D Printed on our lab’s Bambu X1C 3D Printer.
Here is a breakdown of the work I completed during this time:
• Updated the design of the LED housing with a diffuser cover.
• Added feature for top and bottom parts of the LED hosing that can be held together by M4 screws.
• Soldered, assembled and tested all four of the digit modules.
UPDATE: 24to 29 May 2025 – COMPONENTS & PROGRAM TESTED
With help from our Fab Lab Alumni, Zhi Hon who advised on the program and on how to connect up the components, I managed to get all the components and program in for my Final Project tested. This is a major milestone in my Final Project. Below is a video of the test.
Another thing that I worked on was the 2 dots between the digits that I like to call dot-dot. The construction method is similar to that of the digits.
I also made the black display frame to hold the 4 digits and “dot-dot” together and also to improve readability of the clock display. I laser cut this black frame on our Trotec Speedy laser cutter.
Here is what it looks like.
Summarizing the work I completed during this time:
• Connected up and tested the components and program
• Created the “dot-dot” in between the digits
• Created the black display frame
The design files and programs up till this point are available here.
Sound
On the other side of the roof slope, I will place my sound system. I have the following components picked out:
Serial MP3 Player
Amplifier module
Speakers
I also have an audio jack cable to connect the Serial MP3 Player with the Amplifier Module.
Control Centre
The Control Centre is the “brains” of the entire project. I am still working on the final board but this current XIAO ESP32C3 board will be sufficient for testing.
ON PRODUCT - 12V SYSTEM
Power
My project is powered by a 12V rechargeable battery that powers the 12V Solenoid ram, with a module to step down to 5V for the other parts of the system operating at 5 Volts.
12V Battery
Step-down Module
Motion Control
The only thing that is intended to move is the solenoid ram. For this, I have a 12V solenoid operating at 2A current.
I also require a relay for the 12V solenoid to receive 5V signals from the ESP32 board.
MOBILE DEVICE
Time/Alarm Setting Controls
After discussing with my colleague (and Fab Academy graduate) Louis, I decided to reduce the number of buttons on the clock as I can have some of these functions on a mobile device. This reduces visual clutter and also reduces the number of interactive buttons that I need to connect to the physical system.
OTHERS
Structure/Housing
I first started on the body of the Battering Ram Alarm Clock in Week 02. Since then, I have 3D printed that model out (in Week 06) to look at it almost every day and to get a good sense of the project.
While this model was a good size, I was annoyed by how the top part came apart from the base so easily since it was only “blu tacked” together. I have since worked on an improved version where I have included sliding rails at where the top part should join with the base.
Admittedly, there is still a lot of work to be done on the top part (the prism) and this is where I am at right now. Also, from the beginning, I have always wanted to finish this project in wood, which I have already purchased some furniture-grade pine wood to machine on the CNC.
Assembly and Integration
To be updated soon…
Bill-of-materials (BOM)
Below is the BOM for my project:
The biggest cost of materials are the wooden pine boards that that purchased. All the main components have arrived.
SCHEDULE
My schedule is as follows:
It consists of 10 stages of completion. I recently had all my materials delivered which means I am at Stage 3 now (as of 17th May 2025). It is getting packed as we moved towards the deadline.
Files
This concludes this week’s assignment.