Posts in Engineering
GOES-R Satellite Latitude and Longitude Grid Projection Algorithm

Calculating latitude and longitude from a GOES-R L1b data file. The GOES-R L1b radiance files contain radiance data and geometry scan information in radians. This information is not enough to plot geographic radiance data right from the file, however, after some geometric manipulation harnessing satellite position and ellipsoid parameters, we can derive latitude and longitude values from the one-dimensional scan angles and plot our data in projected formats familiar to many geographic information tools.

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iPhone Datalogger with Arduino Using The iOS Bluetooth App BLExAR

The BLExAR app will be used in conjunction with a CC2541 (HM-10, JDY-08, AT-09, SH-M08) Bluetooth module and an Arduino (ATmega328) board to create a simple data acquisition system. A DHT22 sensor will provide temperature and humidity data to the Arduino which will be recorded by an iOS device via the BLExAR app. This experiment is a real-world example of an Arduino application demonstrating data acquisition from a real sensor. This tutorial will allow users to solve their own engineering problems using the modern Arduino platform and wireless communication through the BLExAr app, which will ultimately expand the reach and compatibility of technology in the classical sciences through exploration and experimentation.

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Arduino Tachometer - Using a Hall Effect Sensor (A3144) to Measure Rotations from a Fan

Arduino tachometer used to calculate the rotational motion of a part. Tachometers read out revolutions per minute (RPM), which tells the user how often a rotating part completes one full rotation. RPM readings are used in the automotive, aerospace, and manufacturing fields. Tachometers can indicate fuel consumption and motor speed, safety of moving parts, and even wind speed indicators. In this tutorial, the speed of a fan is measured using a hall sensor and neodymium magnet to acquire an accurate depiction of fan speed.

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Audio Processing in Python Part III: Guitar String Theory and Frequency Analysis

In this continuation of the audio processing in Python series, I will be discussing the live frequency spectrum and its application to tuning a guitar. I will introduce the idea of nodes and antinodes of a stringed instrument and the physical phenomena known as harmonics. This will give us a better idea of how to tune the guitar string-by-string and also discern the notes of a given chord - all calculated using the FFT function in Python.

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Audio Processing in Python Part II: Exploring Windowing, Sound Pressure Levels, and A-Weighting Using an iPhone X

Raspberry Pi 3B+ acoustic analysis using Python. Audio recording and signal processing with Python, beginning with a discussion of windowing and sampling, which will outline the limitations of the Fourier space representation of a signal. Discussion of the frequency spectrum, and weighting phenomenon in relation to the human auditory system will also be explored. Lastly, the significance of microphone pressure units and conversion to the decibel will be briefly introduced and explained.

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Audio Processing in Python Part I: Sampling, Nyquist, and the Fast Fourier Transform

Fourier Series has been widespread in applications of engineering ranging from heat transfer, vibration analysis, fluid mechanics, noise control, and much more. After evolutions in computation and algorithm development, the use of the Fast Fourier Transform (FFT) has also become ubiquitous in applications in acoustic analysis and even turbulence research. In this tutorial, I describe the basic process for emulating a sampled signal and then processing that signal using the FFT algorithm in Python. This will allow the user to get started with analysis of acoustic-like signals and understand the fundamentals of the Fast Fourier Transform.

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Heat Transfer of the Raspberry Pi Using Arduino, An Infrared Thermometer, and Type-K Thermocouple
A Heat Transfer Experiment with Coffee