[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55d9f88f982ec”][wmd-toggle-tab title=” GSoC-15 Project: Sensor Plug-ins, Add-on devices and GUI Improvements for ExpEYES”]Organization%3A%20FOSSASIA%0D%0AMentors%3A%20Hong%20Phuc%2C%20Mario%20Behling%2C%20Rebentisch%0D%0AAbstract%3A%20%0D%0AExpEYES%20is%20an%20Open%20Source%20Pocket%20Science%20Lab%20for%20developing%20science%20experiments%2C%20classroom%20demonstrations%20and%20a%20test%20equipment%20for%20electronics%20hobbyists.%20This%20proposal%20aims%20to%20improve%20the%20GUI%5C%27s%2C%20add%20new%20Sensor%20Plug-ins%20to%20measure%20various%20parameters%20and%20to%20enhance%20the%20scope%20of%20ExpEYES%20for%20using%20it%20to%20perform%20several%20new%20experiments%20with%20low%20cost%20devices.%20Our%20aim%20is%20also%20to%20develop%20a%20low-cost%20stand%20alone%20data%20acquisition%20system%20that%20can%20be%20used%20for%20weather%20monitoring%20or%20environmental%20studies.%0D%0A[/wmd-toggle-tab][/wmd-toggle]

 The aim of my GSoC-2015 project is to develop  new Sensor Plug-ins for ExpEYES  to measure a variety of parameters like temperature, pressure, humidity, wind speed, acceleration, tilt angle, magnetic field etc. and provide low-cost, effective and open source laboratory equipment to students all over the world.

This development is intended to enhance the scope of ExpEYES for using it to perform several new experiments. Developing a low-cost stand alone data acquisition system that can be used for weather monitoring or environmental studies is another objective of our project.

I am happy to see that the things have taken good shape with additional gas sensors added which were not included in the initial plan and we have  almost achieved all the objectives of the project, except for some difficulties in calibrating sensor outputs and documentation. This issue will be solved in a couple of days.

In the beginning, during community bonding period, I started exploring and experimenting with different sensors. After doing preliminary studies I procured  analog and a few digital sensors for measuring weather parameters like temperature, relative humidity and  barometric pressure. A few other sensors like low cost piezoelectric sensor, accelerometer ADXL-335, Hall effect magnetic sensor, Gyro-module etc were also added to my GSoC laboratory.

After the mid-term we decided to add gas sensors  for detecting Carbon Monoxide, LPG and Methane. With this development ExpEYES can now be used for pollution monitoring and also in safety systems in Physics/chemistry laboratory. ( Work on low-cost Dust Sensor is under progress)

Here is the gallery of all the sensors I played with for PSLab..

The complete list of sensor plug-ins developed is here….

Below are the highlights of the work done……the description of the sensors used, GUI’s designed the code written and the possible applications.

( Updated on 23rd August 2015)

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55d999a91d3cb”][wmd-toggle-tab title=”Accelerometer”]An%20accelerometer%20is%20a%20device%20that%20measures%20proper%20acceleration%20%28%22g-force%22%29.%20Proper%20acceleration%20is%20not%20the%20same%20as%20coordinate%20acceleration%20%28rate%20of%20change%20of%20velocity%29.%20For%20example%2C%20an%20accelerometer%20at%20rest%20on%20the%20surface%20of%20the%20Earth%20will%20measure%20an%20acceleration%20g%3D%209.81%20m%2Fs2%20straight%20upwards.%20By%20contrast%2C%20accelerometers%20in%20free%20fall%20orbiting%20and%20accelerating%20due%20to%20the%20gravity%20of%20Earth%20will%20measure%20zero.[/wmd-toggle-tab][/wmd-toggle]

Sensor Used:  ADXL-335

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55d9a2958c08d”][wmd-toggle-tab title=”Relative Humidity Sensor”]Relative%20humidity%20is%20an%20important%20metric%20used%20in%20weather%20forecasts%20and%20reports%2C%20as%20it%20is%20an%20indicator%20of%20the%20likelihood%20of%20precipitation%2C%20dew%2C%20or%20fog.%20In%20hot%20summer%20weather%2C%20a%20rise%20in%20relative%20humidity%20increases%20the%20apparent%20temperature%20to%20humans%20%28and%20other%20animals%29%20by%20hindering%20the%20evaporation%20of%20perspiration%20from%20the%20skin.%20%20Ref%3A%20wikipedia.org[/wmd-toggle-tab][/wmd-toggle]

Humidity sensor HS-1101

Humidity-Temperature Sensor DHT-11

• Frequency output circuit using timer 555
• Proportional voltage output circuit
• Direct capacity measurement using ExpEYES

ExpEYES has ability to measure capacitance of the order of few pF. Therefore decided to to go for third method as it gives better accuracy.

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55d9b453979f0″][wmd-toggle-tab title=”Temperature Sensors”]Platinum%20resistance%20thermometers%20%28PRTs%29%20offer%20excellent%20accuracy%20over%20a%20wide%20temperature%20range%20%28from%20%E2%80%93200%20to%20%2B850%20%C2%B0C%29.%20Standard%20sensors%20are%20are%20available%20from%20many%20manufacturers%20with%20various%20accuracy%20specifications%20and%20numerous%20packaging%20options%20to%20suit%20most%20applications.%20Unlike%20thermocouples%2C%20it%20is%20not%20necessary%20to%20use%20special%20cables%20to%20connect%20to%20the%20sensor.%0D%0A%0D%0AThe%20LM35%20series%20are%20precision%20integrated-circuit%20temperature%20sensors%2C%20whose%20output%20voltage%20is%20linearly%20proportional%20to%20the%20Celsius%20%28Centigrade%29%20temperature.%20The%20LM35%20thus%20has%20an%20advantage%20over%20linear%20temperature%20sensors%20calibrated%20in%20%CC%8A%20Kelvin%2C%20as%20the%20user%20is%20not%20required%20to%20subtract%20a%20large%20constant%20voltage%20from%20its%20output%20to%20obtain%20convenient%20Centi-%20grade%20scaling.%20%0D%0A[/wmd-toggle-tab][/wmd-toggle]

Sensors Used LM-35 and PT-100

Temperature Sensor PT-100

LM-35 Temperature Sensor with ExpEYES

Plot shows temperature changes while hot air is blown on the sensor

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55d9bf7fc9dc2″][wmd-toggle-tab title=”Weather Station”]A%20weather%20station%20is%20a%20facility%2C%20either%20on%20land%20or%20sea%2C%20with%20instruments%20and%20equipment%20for%20measuring%20atmospheric%20conditions%20to%20provide%20information%20for%20weather%20forecasts%20and%20to%20study%20the%20weather%20and%20climate.%20The%20measurements%20taken%20include%20temperature%2C%20barometric%20pressure%2C%20humidity%2C%20wind%20speed%2C%20wind%20direction%2C%20and%20precipitation%20amounts.%20%20%20Ref%3A%20Wikipedia[/wmd-toggle-tab][/wmd-toggle]

The sensor plug-ins for temperature, pressure, humidity and wind speed etc are combined to make all these measurements simultaneously. The GUI program is written to plot data in real time. Trials to fetch weather data by connecting ExpEYES to Raspberry-pi are successful.  Now calibration of anemometer readings is to be done.

Next immediate goal for this work is to complete calibration and do a pilot project to collect weather data in our college campus. Another important thing that we will try is to push the weather data to Loklak server  and display it on the map. I will be trying to replace three cup anemometer with  pc fan anemometer. I think it may provide stability and better accuracy.

 The Code is here…

Random data to show sensitivity of the sensors connected

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55da062ee4422″][wmd-toggle-tab title=”Auto Tweeting Weather Data from PSLab using tweepy”]Python%20is%20great%20language%20for%20all%20sorts%20of%20things.%20Very%20active%20developer%20community%20creates%20many%20libraries%20which%20extend%20the%20language%20and%20make%20it%20easier%20to%20use%20various%20services.%20One%20of%20those%20libraries%20is%20tweepy.%20Tweepy%20is%20open-sourced%2C%20hosted%20on%20GitHub%20and%20enables%20Python%20to%20communicate%20with%20Twitter%20platform%20and%20use%20its%20API.%0D%0A%0D%0A%0D%0ARef%3A%20%20http%3A%2F%2Fpythoncentral.io%2Fintroduction-to-tweepy-twitter-for-python%2F[/wmd-toggle-tab][/wmd-toggle]

Wrote a python program to fetch weather data and auto-tweet using tweepy module. Using this program one can auto-tweet data at desired intervals of time. ExpEYES with Raspberry-pi is now a low-cost stand-alone portable weather station… 🙂

Link to the code on git-hub….

Auto-tweeting weather data from PSLab – Trials with temperature and humidity sensor

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55d9cfd10a373″][wmd-toggle-tab title=”Hall Magnetic Sensor”]A%20Hall%20effect%20sensor%20is%20a%20transducer%20that%20varies%20its%20output%20voltage%20in%20response%20to%20a%20magnetic%20field.%20Hall%20effect%20sensors%20are%20used%20for%20proximity%20switching%2C%20positioning%2C%20speed%20detection%2C%20and%20current%20sensing%20applications.%0D%0A%0D%0ARef%3A%20Wikipedia[/wmd-toggle-tab][/wmd-toggle]

Sensor Used : Hall Sensor -3144 and Module KY-003

Exploring  the use of this magnetic sensor for measuring rotational speed of anemometer and other measurements was quiet interesting experience.  Tried Hall sensor 3144 and KY-003 module.

The KY-003 is a magnetic switch. If no magnetic field is present, the signal line of the sensor is HIGH (3.5 V). If a magnetic field is presented to the sensor, the signal line goes LOW, at the same time the LED on the sensor lights up. The polarity of the magnetic field is of influence to the switching action. The front side of the sensor needs the opposite polarity as the back of the sensor to switch on.

The GUI for Hall Magnetic Sensor module KY-003 is ready and tested. This will be useful in a range of measurement functions including proximity switching, positioning, speed detection, and current sensing applications.

I am now working on modifying the program to use it for speed detection of motors fans and also for measuring periodic time in oscillating systems. This is a low-cost solution for many oscillation experiments.. 🙂

KY-003 Module and a3144 Sensors

Magnetic Sensor with a rotating magnet with ExpEYES

 

 

 

 

 

KY-003 Sensor – Plot with a rotating magnet near it.

 

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”8″ ls-id=”55d9d97704535″][wmd-toggle-tab title=”Gas Sensors”]Methane%20Gas%20Sensor%20MQ-4%0D%0AThis%20semiconductor%20gas%20sensor%20detects%20the%20presence%20of%20methane%20%28CNG%29%20gas%20at%20concentrations%20from%20300%20ppm%20to%2010%2C000%20ppm%2C%20a%20range%20suitable%20for%20detecting%20gas%20leaks.%0D%0A%0D%0ALPG%20Gas%20Sensor%20MQ-6%0D%0AThis%20%20sensor%20detects%20the%20presence%20of%20LPG%2C%20isobutane%2C%20and%20propane%20at%20concentrations%20from%20300%20to%2010%2C000%20ppm.%20%0D%0A%0D%0ACarbon%20Monoxide%20Gas%20Sensor%20MQ-7%0D%0AThis%20gas%20sensor%20detects%20the%20presence%20of%20Carbon%20Monoxide%20at%20concentrations%20from%2010%20to%2010%2C000%20ppm.[/wmd-toggle-tab][/wmd-toggle]

Recently while I was thinking on what new sensors can be added to ExpEYES, I remembered our conversations with Roland Turner and his Yahi Project during FOSSASIA. I started exploring use of Gas sensors for environmental monitoring.

Procured and tried  following sensors…

1. MQ-7 : Carbon Monoxide Gas Sensor

2. MQ-6 : LPG Gas Sensor

3. MQ-4 :Methane Gas Sensor

MQ-7 with Break-out board

MQ-6 and MQ-4 Gas Sensors with Break-out board

Soldered these sensors on separate breakout boards and wrote a python program to interface them with ExpEYES. Completed  GUI programs for Gas Sensors MQ-4, MQ-6 and MQ-7 and also wrote a program for common GUI. Tested the program with LPG and smoke from vehicle exhaust. Things are working as expected. Need to calibrate this set-up with a standard equipment, which I will be doing later.

This new development has brought many new possibilities of using ExpEYES in many other fields like chemistry and environmental studies.

Next To Do.

1.Calibration to get readings in ppm

2. Add Dust sensor

3. PH sensor ( Currently not able to do it because low cost sensors are not available. Searching for alternatives)

The code for gas sensor GUI’s is here…

Gas Sensors GUI tested for carbon monoxide (MQ-7) by generating smoke using a match stick.

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Modifications in Existing GUI’s developed during GSoC-14

• GUI for using Motion sensor SRF-05, (ultrasonic position sensor) is modified  for plotting real-time position.
• Made necessary changes in GUI for Lissajous Figures using ATTINY85.
• Added Python-3 compatibility to all ExpEYES programs developed for GSoC-2014 Project

Ultrasonic Position Sensor SRF-05

ATTINY -85 MCU for Lissajous Figures

 

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”4″ ls-id=”55d9e004910b3″][wmd-toggle-tab title=”Voltammetric Measurements for Research in Nanotechnology”]Voltammetry%20experiments%20investigate%20the%20half%20cell%20reactivity%20of%20an%20analyte.%20Voltammetry%20is%20the%20study%20of%20current%20as%20a%20function%20of%20applied%20potential.%20These%20curves%20I%20%3D%20f%28E%29%20are%20called%20voltammograms.%20[/wmd-toggle-tab][/wmd-toggle]

My colleague Dr. (Mrs) Smita Kalagi  is doing research on nano-materials and needed equipment for voltammetric measurements. I tried writing a python program for plotting voltammogram using ExpEYES and  could carry trial  measurements successfully. This development has resulted in a low cost, open source quality research equipment… 🙂

 Voltammetry is analytical method used in chemistry and various industrial processes. In voltammetry information about an analyte is obtained by measuring the current as the potential is varied.

Will update with the actual set-up in the laboratory and experimental results soon…:)

Here is the code….

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”4″ ls-id=”55d9e5010364a”][wmd-toggle-tab title=”Internationalization: French Localization”]GNU%20%60gettext%5C%27%20is%20an%20important%20step%20for%20the%20GNU%20Translation%20Project%2C%20as%20it%20is%20an%20asset%20on%20which%20we%20may%20build%20many%20other%20steps.%20This%20package%20offers%20to%20programmers%2C%20translators%2C%20and%20even%20users%2C%20a%20well%20integrated%20set%20of%20tools%20and%20documentation.%20Specifically%2C%20the%20GNU%20%60gettext%5C%27%20utilities%20are%20a%20set%20of%20tools%20that%20provides%20a%20framework%20to%20help%20other%20GNU%20packages%20produce%20multi-lingual%20messages.%0D%0A%0D%0ARef%3A%20http%3A%2F%2Fwww.gnu.org%2Fsoftware%2Fgettext%2F[/wmd-toggle-tab][/wmd-toggle]

This indeed is a good news for Pocket Science Lab Project. I have been adding support for  internationalization based on Gettext, in all the python programs being developed for pocket science lab.  This work was originally done for ExpEYES  by Mr Georges from France. Now he has added French localization to Pslab… as a result all the GUI’s will be available in french … 🙂

Here is the link for French Localization of PSLab…..

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”4″ ls-id=”55d9e8544e8fb”][wmd-toggle-tab title=”Piezoelectric Transducer”]A%20piezoelectric%20sensor%20is%20a%20device%20that%20uses%20the%20piezoelectric%20effect%2C%20to%20measure%20changes%20in%20pressure%2C%20acceleration%2C%20temperature%2C%20strain%2C%20or%20force%20by%20converting%20them%20to%20an%20electrical%20charge.%20The%20prefix%20piezo-%20is%20Greek%20for%20%5C%27press%5C%27%20or%20%5C%27squeeze%5C%27.[/wmd-toggle-tab][/wmd-toggle]

Piezoelectric Transducers

Cheap piezoceramic membrane used in piezoelectric ‘buzzers’ can be used as a very inexpensive, accurate and sensitive pressure sensor. These devices can be used both as sensors and actuators, so they’re referred to as transducers, a term applied to any device that can convert one form of energy to another. The sensor turns mechanical energy into electric potential, and the actuator converts electrical energy into mechanical force or motion.

The Piezoelectric material used here, ceramic lead zirconate titanate known as PZT has the ability to provide twice the voltage of Quartz under a given force. These transducers are simple, reliable, and very robust, and so find wide use in industry, medicine, and aero-space work. They’re unaffected by external electromagnetic fields, and so can be used in applications where electronic sensors would fail. They are stable over a broad range of temperatures, but may be effected by long use at high temperatures.

 The GUI program for Piezoelectric Transducer as force/impact sensor is here…

GUI for using Piezo Sensor as Force/Impact Sensor

[wmd-toggle tab_background=”#75a5ce” tab_color=”#fff” content_background=”#93e9ea” content_color=”#725d53″ border_radius=”4″ ls-id=”55d9e5a6ad355″][wmd-toggle-tab title=”Some Other Sensor Plug-ins and Open Source Devices”/][/wmd-toggle]

IR Object Sensor

Made a simple Infra-red object sensor using IC LM358 (got a ready-made circuit board from local market). Wrote a GUI  program for IR sensor and tested it. Added a potentiometer to the circuit. It can be used to modify sensitivity or range of the sensor.

Link to Code…

IRobject-sensor

Barometric Pressure Sensor BMP 180

Tested BMP180 Digital Barometric Pressure Sensor Board Module :This precision sensor from Bosch is the best low-cost sensing solution for measuring barometric pressure and temperature.  ( Need to re-write the program to read data accurately) (Work in Progress)

I could interface BMP-180 with MicroHope but facing some issues with interfacing it with ExpEYES. The data obtained is not matching with standard module from our Geology Lab. I am searching alternate sensor/method to measure atmospheric pressure.

 DC Motor as Rotatory Motion Sensor

Sensor Used:    DC Motor and a pick-up coil

Photo Gate

Sensor Used:    Photo Gate using Photo Diode15.

The GUI program written during GSoC-14 project is modified for measuring periodic time in oscillatory motion and also to measure acceleration due to gravity.

Other devices used

Solar Cells
Induction coil

GY-271 module
condenser MicLight Sensor ( Work in progress)
ATTINY-85 MCU used for sine wave generation
Raspberry Pi 2 Model B for stand-alone weather station
MicroHope : Micro-controller development system from ExpEYES Project

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Plan for next four months

• Calibration of sensor data
• Prototyping stand-alone weather station
• Pushing data to Loklak server
• Work on PSLab@Fossasia website
• Fossasia Live Cd based on Lubuntu with ExpEYES and other educational softwares
• Set-up Documentation for possible science experiments with the sensor plug-ins and low-cost, open source apparatus

[wmd-toggle tab_background=”#2e99ba” tab_color=”#fff” content_background=”#9adff4″ content_color=”#fff” border_radius=”4″ ls-id=”55da126f61694″][wmd-toggle-tab title=”My Git Hub Profile”]%3Cp%20style%3D%22text-align%3A%20center%3B%22%3E%3Ca%20href%3D%22https%3A%2F%2Fgnovi.edublogs.org%2Ffiles%2F2015%2F08%2Fgithubprofile-1n1wjhf.jpg%22%3E%3Cimg%20class%3D%22alignnone%20size-large%20wp-image-600%22%20src%3D%22https%3A%2F%2Fgnovi.edublogs.org%2Ffiles%2F2015%2F08%2Fgithubprofile-1n1wjhf-1024×718.jpg%22%20alt%3D%22githubprofile%22%20width%3D%22584%22%20height%3D%22409%22%20%2F%3E%3C%2Fa%3E%3C%2Fp%3E[/wmd-toggle-tab][/wmd-toggle]