Project description:
Post date: Feb 12, 2016 3:21:35 AM
Learning from my last project Dust and particles monitoring with Sharp GP2Y1010AU0F I have now a better idea of what i can achieve with the sharpGP2Y1010dust sensor.
My first decision was to forgot about the idea of a solar cell autonomous outdoor dust sensor. My previous outdoor sensor is indeed autonomous on a bright sunny day but not on a cloudy or even worst rainy day. The purpose of the sensor is to monitor the dust density while our ara is affected by forest or pit land fire in sumatra and my experience show me that a bad day of fume haze got an uv index on sunny day between 2 an 3 versus 15 on clear sunny day. Which is not going to be enough to charge the battery pack and feed the electronic. Never mind i have an easy access to 220 VAc on the pole of my weather station so i will develop ( and publish it in future post) an outdoor sensor MarkII without any power saving nor sleeping mode....
What do i have in stock.
One arduino uno of course as well as a deprecated arduino wifi shield and its micro SD card reader.
I don't know why this product has been retired, because it's a good product that doesn't give me to much trouble to work with.
An extra sharp dust sensor GP2Y1010 to make the indoor sensor. I actually received a GPY1050 as extra sensor. i'll told you little bit later about the difference.
3 micro servo 9g to use as needle gauge reading.
The usb receiver from the 3DR telemetry kit. Which i'll have to hack a bit to plug it to the arduino.
A DFR robot prototype shield compatible arduino uno.
a 12VDC 1A wall mart power supply.
What is the idea ?
The Arduino board will decode (via the 3DR telemetry receiver) the outdoor dust density send by the outdoor sensor.
It will measure as well the dust density reading from the indoor sensor.
- send the reading to a mysql database hosted on a linux server on the network via the aduino wifi shield.
- get from the same mysql database a calculated average of the outdoor dust density average on the last 24 h.
The indoor, outdoor dust density and the average will be display via 3 9g micro servo on 3 graduated semi circle with a resolution of 180° for 550μgram/ m3.
The mysql database data must be graphical and numerically available from a web php page hosted on linux samba web server.
The mechanism to post and get data to and from a linux server will use php and mysql . The arduino will talk to the mysql server through some php pages.
To graphically display the dust density on a web page i want to give a try to the D3 javascript library which look very interesting for web data display.
Sketching around:
I first did some test with the wifi shield and it's SD reader with the idea of data logged the dust density on micro SD and getting the time from an NTP server on the net.
It's easy to read or write data on the SD card but the SD library got a very heavy foot print on the memory. apparently the library create big array variable and if i compile a code with just the SPI and SD library it's using already 39% of the memory on an arduino uno. It's leaving to little memory available for the rest of my code.
To data log on the SD card i need to add a time stamp on each data recorded. so i try to use UDP/NTP protocole to get the the time from an internet time server.
i found on the arduino playground forum the following low memory foot print ntp function who return the unix time.
So, no data logging and NTP time will be used for this project.
Difference between the sharp GP2Y1010 and GP2Y1050:
The two sensor look very similar, same casing, same connector and same wiring colour.
check picture below:
GP2Y1010
GP2Y1050
The obvious difference is the position of the connector and the capacitor already soldered on the connector. The GP2Y1010 is provided with an external capacitor between pin 1 and 2.
I didn't find any datasheet for the ref GP2Y1050. so i give a try like this hopping that the only difference between the two is only the capacitor already integrated on the GP2Y1050. But it doesn't work at all it give me a constant 1023 reading on the analog pin. i check the 6 pin with my oscilloscope and notice that one pin was having a kind of PWM (pulse width modulated) signal.
Digging a bit more on the net i find out that the GP2Y1050 sensor was still under development at sharp electronic and i found a kind of datasheet in Chinese only from a alibaba style trading Chinese website. (see file attached below).
Apparently the GP2Y1050 is using only 3 pins out of the 6 and the exit is Pulse Width Modulated. No need to drive externally the Led anymore, you just provide Vcc and Gnd and read the PWM result on one pin. but my chinese is not good enough to find out how to translat the dust density ou of the PWM signal.
So i asked to my dealer to exchange it with the proper ref i have ordered ....