I've been diving deep into the world of PCB (Printed Circuit Board) coils, inspired by Carl Bugeja's incredible PCB motors! After deciding to set up an automated process for creating the coils rather than manually drawing them (can you imagine?), I found our main constraints became track width and spacing, and the number of layers we could use. During the process of creating spirals for our coils, I encountered some interesting problems - spirals are easy, but what about arbitrarily shaped coils? My attempts ultimately lead me to develop more efficient algorithms and KiCad plugins to generate these special coils....
23 October 2022
In this blog post, I share how you can avoid hassles of SSH and use VSCode for remotely developing on the Raspberry Pi. I walk through how to initially configure the Pi in a headless setup using the Pi imager app. Then, we install the 'Remote Development' extension in VSCode. I illustrate how easy it is to connect to the Pi using our SSH credentials, clone a GitHub project, and install python extensions. Finally, I explore how to run the code and debug it. However, note that the method doesn't support armv6, so you can't use it on Pi Zero....
24 September 2022
I was fortunate enough to enter the world in 1971 alongside Intel's 4004 microprocessor – a moment that ushered in the digital era as we know it. Although a bit of an educational renegade, my curiosity steered me down a path filled with ZX Spectrums, Christmas wish lists, dangerously strewn cables and a legion of half-disassembled childhood toys. In spite of the haphazard approach to my intellectual explorations, I eventually managed to grasp the fundamentals of assembly language and savoured the glory of publishing a small utility, all whilst navigating the complex prepubescent minefield of Dungeons & Dragons. Looking back,...
19 August 2022
Battling YouTube's frustrating algorithms, I’ve decided to take matters in my own hands. Why rely on YouTube to reach my audience when I, along with a group of fellow Makers around the world, can start up a newsletter to directly connect with our fans? To spice things up, this won't be just about showcasing our work. We plan on sharing a curated list of interesting content, compelling long reads, plus some spotlight features on lesser-known Makers. Ready to shake things up a bit? Subscribe and share our newsletter with your friends! Your engagement is the best way to defy the...
06 August 2022
In this blog post, I explore the TS80P soldering iron, a tool that has been generating buzz. One of the highlights is that its firmware can be flashed with an open source system called IronOS. Here, I share my process of flashing the TS80P with IronOS and testing it out on a Raspberry Pico W. Please note, a Quick Charge or Power Delivery supporting power supply is needed for this iron. While running some tests, I observed that using a fast charger can heat this iron up twice as fast as using an Apple charger. Also, flashing the firmware is...
04 August 2022
Wow, one of my videos hit 1.8 million views! Mind-blowing, right? But is it really a 'successful' YouTube video? To answer that, I compared my stats with mega channels like MrBeast and niche channels like GreatScott and The Guy with the Swiss Accent. Shockingly, in comparison to these giants, my 1.8 million views on a single video do seem quite a success, considering my average views often max out at 28K! The comments have been both hilarious and strange, and the video did lead to a substantial boost in my subscribers count. But did it pay off? Well, the video...
27 July 2022
This blog post reveals how you can salvage lithium cells from the many discarded, disposable vape devices that get littered in our towns and cities. With a pair of pliers and some bravery, I managed to rescue some decent batteries, which still had a good amount of power in them. However, with no in-built protection in these cells, I also demonstrated the importance of adding a battery protection board to ensure they are safe for use in various projects. Conclusively, through rummaging in the trash, I not only acquired useful components for my projects but also took a step towards...
16 July 2022
After some stress and trepidation, I finally took the plunge and sent my PCB design off for manufacturing. My design centers around building a large seven-segment clock with LED filaments. Jumping hurdles such as voltages, pin usage, and limiting the load on my power supply, I've settled on the ESP32 as the system's heart and come up with a final circuit design. While doing this, I've quickly realized I could improve my layout and fixed a small mistake. Also, I've prepared for either types of LED filaments - the high-voltage ones or the larger, 3v ones. However, I did bungle...
06 February 2022
In this blog post, we delve deep into the intriguing concepts of I2S audio and DMA, particularly focusing on parameters like dma_buf_count and dma_buf_len. We explore their roles, ideal values, and the impacts they have on aspects such as CPU load and latency. We also discuss the limitations that come hand in hand with these parameters. This post aims to provide you some insights on trading-off between latency, CPU load, memory usage and the overall buffer space allocation. However, the primary takeaway remains that the optimal configurations largely depend on individual context and application needs.
20 April 2021
This blog outlines the absolute fundamental elements that any competent team needs to ensure smooth operations. It emphasizes the importance of continuous integration, continuous deployment, running effective unit tests, comprehensive code reviews, and the ability to run the system locally. The objective here is not to over-complicate procedures, but to streamline consistent quality through these five basic yet crucial practices which when implemented should mark an effective team.
26 November 2020
This post provides a comprehensive guide to building a do-it-yourself (DIY) Alexa using an ESP32 and Wit.ai. It illustrates how to create a wake word detection system, use Python for machine learning and employ TensorFlow for the 'wake' word identification. It also covers the usage of Wit.ai for intent recognition and managing commands. The post is fully backed with code snippets, examples and video tutorials to deliver an interactive learning experience to readers.
15 October 2020
In this blog post, I've delved deep into the world of audio input for ESP32, exploring all the different options for getting analogue audio data into the device. After discussing the use of the built-in Analogue to Digital Converts (ADCs), I2S to read ADCs with DMA, and using I2S to read directly from compatible peripherals, I go on to present hands-on experiments with four different microphones (MAX4466, MAX9814, SPH0645, INPM441). This comprehensive look at getting audio into the ESP32 should be a valuable resource for anyone hungry for a deep-dive into ESP32's audio capabilities, complete with YouTube videos for an...
12 September 2020
In this blog, I venture beyond binary classification and delve into categorical classification using TensorFlow. Specifically, I show how to generate and classify images into four categories: blank, square, circle, and triangle. Crucially, I highlight the use of one-hot encoding for labeling and the softmax activation function in our model. I provide examples of code, results of my model's predictions, and link to the full code in my GitHub repository. Feel free to try it out and explore this exciting domain of machine learning further.
06 September 2020
In this playful tutorial for binary classification aided by visuals, we create a Python generator that generates alternating images of squares and circles, which we then classify using TensorFlow. We take special care to point out, too, that to get binary classification up and running, we must use a particular activation function and loss function. After training our model, illustrations show that it's excellent at identifying images as either squares or circles. So, if you're into Machine Learning and has a sense of humor, don’t forget to check out the 'hot dog or not hot dog' bit and visit the...
06 September 2020
In this post, I reminded myself about some peculiarity with TensorFlow's tf.random.shuffle. I assumed that using the same seed for two shuffle operations would always output the same results but turns out, I was wrong! I discovered that I need to set the global seed with tf.random.set_seed() before every operation to get consistent results. Definitely a lesson learned to pay a bit more attention to TensorFlow's well written documentation about seeds usage for random operations.
04 September 2020
Logging errors and exceptions are often the bare minimum folks set-up but hey, it's time we optimized this! We need log trails that allow us to follow the code - the 'happy path'. Why, you ask? To be able to trace user reported bugs, have a visual of where the code went rogue and save tons of debugging time. Next time you set up your logging system, remember these words of wisdom.
28 August 2020
Today, we dissected a classic programmer joke about the stages of debugging and why we find it funny while it reflects a dire situation. We pondered why our first instinct is to dismiss a bug, dug into invalid claims about machines, and appreciated the shift from denial and blame to accepting responsibility and finding solutions. After deconstructing the old stages of debugging, we reconstructed healthier, proactive stages with prime focus on problem-solving. Next, we explored different types of bugs from easy user interface bugs to the complex Heisenbugs. Lastly, I highlighted logging, debuggers, and good old human brainpower as instrumental...
25 August 2020
This blog showcases the progress of my idea to create an augmented reality Sudoku solver using technology that enables us to solve puzzles in our browser rather than with dedicated apps. I have developed an AR Sudoku solver with a simple image processing pipeline. It identifies and extracts Sudoku puzzles from pictures, recognizes each cell's numbers, solves the puzzle, and renders the solution on top of the original image. This process is accomplished by converting the image to greyscale, conducting thresholding, OCR-processing, and puzzle-solving. I've also done parallel image location and extraction. It's a technical journey that's achieved some high-quality,...
25 July 2020