Inkjet printing of text or photos as solar cells


by Denis Meyer @

Research is in progress at the University of Aalto in Finland on the development of a process for inkjet printing of text, photos or any illustrations as solar cells. The idea is not new but these researchers are covering new ground which will allow the use of ordinary materials. According to Janne Halme: “The difficulty has been the development of solvents which are both clean and photovoltaic and give a good print quality”.

Inkjet printing of text or photos as solar cells – [Link]

Combo sensors fit wearable devices

Kionix KXG0708
Two combination accelerometer-gyro sensors, the KXG07 and KXG08 from Kionix, a subsidiary of Rohm, provide six axes of motion sensing. Both devices feature a configurable low-power architecture and a large 4096-byte FIFO buffer with timestamps for use in gaming systems, smart phones, and wearable devices. by   @
Unlike conventional sensor signal-detection methods based on amplitude detection, the KXG07 and KXG08 use a proprietary phase-detection scheme that contributes to smaller designs, while enabling full high-speed operation of the onboard accelerometer, gyroscope, and temperature sensor at power consumption levels as low as 0.2mA, allowing for always-on operation. Each device offers I2C and SPI digital outputs with user-programmable gyroscope full-scale ranges of ±64°/s, ±128°/s, ±256°/s, ±512°/s, ±1024°/s, and ±2048º/s and user-programmable accelerometer full-scale ranges of ±2 g, ±4 g, ±8 g, and ±16 g.

Combo sensors fit wearable devices – [Link]

The IoT Project Builder “myDevices” Has Added Arduino Support

“myDevices”, creators of IoT platform Cayenne, announced in a press release a partnership with Arduino to integrate Arduino support in their system. The partnership seems to be with Arduino SRL not with Arduino LLC.

The currently supported Arduino boards, beside variety of sensors and actuators, are:

  • Arduino Due
  • Arduino Leonardo
  • Arduino Mega
  • Arduino Nano
  • Arduino Pro Micro
  • Arduino Pro Mini
  • Arduino Uno
  • Arduino Yun
  • Ethernet and WIFI Shields

To write your application code you need to add Cayenne library to your Arduino IDE.

How to use Arduino with Cayenne:

An overview of Cayenne:

Cayenne is a drag and drop IoT project builder, gives the hardware developers the ability to have their own apps without having any background in web or mobile development.

Cayenne platform has two major parts,a Cayenne Mobile Apps to monitor and control your IoT projects remotely from the Android or iOS Apps, and Cayenne Online Dashboard with customizable widgets to visualize data, set up rules, schedule events.


The main Cayenne features are:

  • Drag-and-drop widgets.
  • Visualize Arduino sensor data.
  • Create triggers & alerts between different platforms.
  • Ability to create widgets for any connected sensor or actuator.
Creating a Trigger
Creating a Trigger

Visit the documentation and resources pages to know more about how to use Cayenne platform.

D7S Vibration Sensor From Omron

Omron announced a new seismic sensor and claims it’s the world’s smallest in size.

D7S sensor is a MEMS 3-axis acceleration sensor featuring OMRON’s unique SI value calculation algorithm, which has a high correlation with the seismic intensity scale that indicates the magnitude of an earthquake and provides higher-precision judgment of seismic intensity scales.

The below diagram describes how D7S works

D7S - Operation Chart
D7S – Operation Chart

The sensor has two open-drain outputs INT1 and INT2. INT1 goes active (low) when shutoff judgment condition and collapse detection condition are met (earthquake level 5 or higher), INT2 goes active (low) during earthquake calculations, offset acquisition and self-diagnostic processing.

I2C is used for communication with the sensor for settings and obtaining earthquake-related information.

D7S - Circuit Diagram
D7S – Circuit Diagram


D7S is a surface-mount compact module with 10.9 × 9.8 mm dimensions. I found the new sensor on Mouser and the price per unit is about $22 (USD) for 1-unit quantity order.


[Product Page]

Arduino Geiger–Müller counter with LCD display


Bob tipped us with his latest project. It’s a custom Arduino shield able to communicate with a Geiger-Muller counter and display data on a LCD display. The data are displayed in two layouts: bar graph of the pulses in one minute interval and histogram of the gathered data.

In the previous posts I’ve described a simple Geiger–Müller counter and various experiments with this device. Today I would like to present Arduino project to communicate with a Geiger-Muller counter, gather data and present it to the user. The device is based on Arduino Uno, Nokia 5110 LCD and homemade shield.

Arduino Geiger–Müller counter with LCD display – [Link]

Disconnect circuit for 12 volt lead acid and lithium batteries


KA7OEI designed a circuit that disconnects the battery when it over-discharges. He writes:

The avoidance of overcharging is usually pretty easy to avoid: Just use the appropriate charging system – but overdischarge is a bit more difficult, particularly if the battery packs in question don’t have a “protection board” with them.

Lead acid batteries (almost) never come with any sort of over-discharge protection – one must usually rely on the ability of the device being powered to turn itself off at too-low a voltage and hope that that threshold is sensible for the longevity of a 12 volt battery system.

Disconnect circuit for 12 volt lead acid and lithium batteries – [Link]

Thermometer 0-99C Using PIC16F1825


This digital temperature meter provides real-time temperature values from 00 to 99 degrees Celsius. The Temperature Monitor project built using PIC16F1825 Microcontroller from Microchip, CAT4016 serial to display driver IC from ON-Semiconductor, DS18200 Temperature sensor and two 7 Segment common anode 0.5 Inch display. This little handy project consumes low current and can be work with 4.5 V batteries, intensity of the display can be change by replacing value of R1, read Cat4016 data sheet for more information about current setting. Display range 00 to 99 degree Centigrade.


  • Supply 4.5 to 5V DC
  • Range 00 to 99 Degree Celsius
  • On Board Power LED

Thermometer 0-99C Using PIC16F1825 – [Link]

dot – The Physical Push Notification

Dot uses precise location tracking to make your smartphone’s notifications highly intelligent and contextual.

dot uses your location to make your smartphone more aware of your surroundings.

Launching Soon. Sign up for updates and get 10% off our Kickstarter!

Dot want to teach your smartphone how to recognize your daily patterns and behaviors in the places that make up your life (bedroom, car, kitchen, garage, desk at work, etc).

dot – The Physical Push Notification [Link]


Environmental Monitoring with TPS, Azure, and PowerBI



Сollect environmental data with Tibbo Project System devices, process it with Azure Stream Analytics and visualize using Power BI.

Environmental Monitoring with TPS, Azure, and PowerBI – [Link]

Using Bluetooth LE in Products

Jone Teel over Makezine walked through how to use BLE (Bluetooth Low Energy ), aka Bluetooth smart, in an electronic product.

BLE, unlike classic Bluetooth, it’s not designed for big data transmission or streaming audio or video. BLE comes in SoC (System on Chip) ICs which combine a RF transceiver and a microcontroller running the Bluetooth stack (firmware) all in a single chip but you can still have the transceiver alone and run the software stack firmware on your processor.

Possible Hardware Configuration in BLE Solutions - Getting Started with Bluetooth Low Energy by Kevin Townsend, Carles Cufí, Akiba, and Robert Davidson (O’Reilly)
Possible Hardware Configuration in BLE Solutions – Getting Started with Bluetooth Low Energy by Kevin Townsend, Carles Cufí, Akiba, and Robert Davidson (O’Reilly)

According to Jone, the software stack of Bluetooth Classic must be purchased separately and costs at least $10,000 USD plus a per unit licensing fee for every unit sold. Now, BLE SoC makers provide the software stack free in most cases. For example, Nordic Semiconductors provides the software stack S110, S120 and S130 SoftDevice for free.

most popular BLE chip solutions - Makezine
most popular BLE chip solutions – Makezine


Jone advises to use ready made BLE modules rather than chips and this will reduce the costs required for FCC certification and eliminate the need for antenna tuning.

Jone ends his article talking about the Antenna design solutions using a ceramic antenna or a trace antenna on PCB.

Via: Makezine