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Easy Pulse mikro is now available on Tindie

Posted on October 10, 2016 by R-B One comment

Easy Pulse mikro, a DIY pulse sensor with a mikroBus form factor, is now available at our Tindie Store. a new addition to our Easy Pulse Sensor series. Its mikroBus form factor enables easy integration with Microchip’s MPLAB Xpress board as well as with mikroElektronika‘s numerous development boards. Similar to our original Easy Pulse V1.1 and Easy Pulse Plugin, it also operates on the principle of transmittance photoplethysmography applied to fingertip using infrared sensors.

Easy Pulse mikro

Easy Pulse mikro provides all necessary instrumentation and amplification on board to detect the cardiovascular pulse signal from the fingertip. The output is a nice and clean analog PPG waveform routed to the AN pin of the mikroBus connector. Now you can buy this sensor from our Tindie Store in United States as well as from Elecrow Store in China.

Smart stick for visually impaired

Posted on October 10, 2016 by R-B Leave a comment

This project article from 4D Systems describes how to build a smart stick that uses sonar to guide visually impaired. It uses 4Duino, which is an Arduino compatible computer board with built in 240×320 resolution TFT LCD Display and Wi-Fi capabilities. The stick consists of three ultrasonic sensors that can sense obstacles in three directions (left, right and front) within a distance of 400 cm. When an obstacle is detected within the range, the user is notified with the activation of a vibration motor. Because 4Duino is WiFi enabled, the user can also send text messages to a web browser for help in emergency situations by simply tapping the TFT screen.

Smart stick for visually impaired

Pallete: An open source tongue computer interface.

Posted on October 10, 2016 by R-B Leave a comment

Designed by Dan Levine, Pallete is a fully open-source wireless computer interface to allow the mobility impaired to control computers, Android tablets and phones using the tongue. It uses infrared sensors to track tongue motion, a microphone to detect tongue taps, and Bluetooth technology for communicating with computers. Dan’s smart mouthguard is also a winner for the Assistive Technologies award of the 2016 Hackaday Prize.

Pallete: The World’s First Open Source Tongue Computer Interface

It is open sourced, all the design source files and instructions are available online. Moreover, it uses off-the-shelf components, so any developer/builder/hacker can follow the instructions and build Pallette. We hope to establish a community around tongue-control technology, so the people in need can actually have access and benefit from it. Winning this competition will help us publicize this project, and hopefully achieve a minimum critical mass for this community!

Open source glucose meter shield

Posted on October 10, 2016 by R-B 2 comments

M. Bindhammer won an award for the Assistive Technologies category of the 2016 Hackaday Prize contest for designing an open source Arduino shield that can measure blood glucose level using electrochemical test strips. His glucose meter shield receives the blood sample through a One Touch Ultra test strip and prints out the glucose level on the Arduino IDE serial monitor window.

Glucose meter shield

Here is a demo video of the glucose meter shield.

Typically the electrodes are coated such that an enzymatic chemical reaction occurs at the electrode surface and this reaction dictates the resulting current. The details of the electrochemistry can be quite complex. Since commercial strips are used, the details are somewhat unknown as the companies do not release detailed data about their particular test strips operation. Some devices apparently watch the current after a short initial transient (the current will level out to some degree) and then report the current after a fixed time. Another principle looks at the total amount of reaction which has occurred and thus integrates the current with respect to time to obtain the total amount of chemical reaction which has occurred. Our glucose meter will make two measurements to determinate which relates more strongly to the glucose level: one is the current after a fixed time and the other is the total integrated current.

HID IR Keyboard using PIC18F25J50

Posted on October 9, 2016 by R-B 2 comments

A PIC18F25J50 based USB HID IR keyboard from Suraj Bhawal uses a TSOP IR decoder IC to receive IR signals from an IR remote and convert them to HID inputs.

HID IR Keyboard

For this project, I used a PIC18F25J50 microcontroller with a TSOP IR decoder. I used this microcontroller because of three reasons. First, this mcu is available in tiny QFN package which helps reducing the overall board size. Second, this mcu supports usb communication without using an external crystal/resonator which again helps reducing the board size. And third, is that I have several of these laying around in my stock. The list of components required to make this project is very tiny. Hence it’s not very hard to build this circuit. But, if you want to build the circuit I built, you’ll need very steady hands and expert soldering skills.