Rui Santos have compiled a list of useful Arduino shields. This is great source if you are looking for ideas for your next project or simply want to try something new. He describes each shield along with eBay link where to purchase. He posts only 25 shields while there are hundreds of them. If you will dig deeper, probably you’ll find a shield for any purpose you may think.
Photoplethysmography (PPG) sometimes called pulse oximetry is on of the easiest ways to get heart rate information. With a little more analyze and signal processing it is possible to extract even more information related to your heart condition like arrhythmia. But first lets focus on how to acquire PPG signals with the things you might have lying around. SteveQuinn have built a PPG device around Arduino Mega2560, 128×160 TFT LCD, and several passives. The measuring of PPG lies on blood perfusion to the dermis and subcutaneous tissue of the skin. Every cardiac cycle pumps blood to peripheral organs and this flow change can be measured with simple optical method – LED and photo diode. There are two ways of measuring PPG waveform – transmissive and reflective. Transmissive method seems to … Continue reading
When you are working with electronics or simply building stuff, you probably always end up testing one or several components for their faults or making sure parameters are within specs. Most of those tasks can be done with multimeter. Obviously any multimeter have resistor and capacitance testing modes. Anyway, there are more components that may be tested and using multimeter might require some setup. Baweja_akshay have built pretty universal component tester which is capable of testing most of non power electronics components. I is capable of testing resistors, capacitors including ESR, BJTs, FETs, MOSFETs, JFETs, Thyristors (SCR, DIAC, TRIAC), IGBTs, diodes. Additionally tester is capable of measuring voltages up to 50V, frequency and even generate signals. Optionally there is an IR code detector. The tester is based on Atmega328 microcontroller … Continue reading
WiFi camera can be handy in many areas where you don’t want tracing wires. They are not expensive if you are looking for complete solution. If your application isn’t critical then why not building one by yourself. Johan simply took two well known modules – arducam and ESP8266 module. He built a baseboard to fit hem both including power supply solution and couple other features like optional SPI flash, FTDI connector. He called his development esparducam – the combined name of both modules. He wrote a demo application where it is possible to get images by using HTTP GET method. If you would like to give it a try, follow his project Github page.
Head of Yandex search services Alexander Sadovsky recently gave a lecture that was both interesting and genuinely informative. However, although the lecture was brilliant as always, the questions and answers that took place afterwards allowed us to shed some light on Yandex trends and modern tendencies. Question: What are you planning to switch off after the backlinks? What will it be? Alexander Sadovsky: We are always trying to switch everything on and not turn it off. We are not eager to get rid of things. We want to give new opportunities and possibilities. Question: Does a career in online marketing have any limitations?
Our homes are filling with energy hungry devices. Some of them are constantly active like fridge, routers, lighting, some switched off or on stand-by. Each of them takes some portion of energy that reflects on the end month bill. Some things you can control, but some not. So in order to hunt inefficient nodes you need some sort of energy usage monitoring. You can find lots of implementations where some are simple indicators, other are advanced and web enabled. TSalwach @ github.com have built his own version of energy monitoring system which looks really promising. His implementation monitors all three phases where he extracts several parameters: RMS Voltages and currents on each phase Apparent power (product of RMS voltage and RMS current) Real (active) power Reactive power with inductance/capacitance indication … Continue reading
You can use GPS data for many interesting projects and experiments. By analyzing logged data you can track the movement of the object, analyze you hiking route, RC plane model, weather baloon and other crazy stuff. Building such logger isn’t very complex task as it involves only standard modules and practically no soldering needs to be done. Almost all standard GPS modules support so called NMEA0183 data format – a short message which contains all data including position and time stamps. Once connected, GPS module automatically sends this data via serial interface. Arduino simply needs to capture it and store data to memory like SD card. In this project, data is stored in FAT32 (or FAT16) formatted SD card. Arduino accesses SD card through SD card V4.0 shield. This is … Continue reading