Piedra, Papel o Tijera

Para descargar la documentación del proyecto de Piedra, Papel o Tijera, puedes hacerlo desde el siguiente enlace:
https://drive.google.com/folderview?id=0B20kHfrc3NnpZ3N4X1ZzTkpEUEU&usp=sharing

Project

This project consist on measuring the temperature of our house from our school.

Material needed:
-1 House with internet and a router
-1 Computer with Labview and Arduino
-1 Relay
-1 TTL-RS232 Adapter (made by ourselves)
-Wires
-1 Raspberry Pi
-1 LM35
-1 smartphone with Putty installed on it

Steps:
1-We send a message which starts with an "h" on the browser, introducing our public IP. For this step, we will have our computer in our house, connected to the internet with LabVIEW and the port 8088.
2-We will take our smartphone with Putty and we introduce our public IP and the port 22, to connect our Raspberry Pi.
3-In putty, we will start the program.
4-LabVIEW will send the message to the Arduino, with the message that we have introduced on it.
5-If the message is wrong, the program will finish. If the message is right, the program will continue and we will see the message introduced in our smartphone.
6-The program will ask us if we want to continue. We will choose Y (yes) or N (no). If we choose yes, we will continue. Else, the program will stop.
7-The program will show the temperature of our house in our smartphone, reading the LM35.

Measurement

This practice consists on the measurement of the size of an object with Vision Builder. Then, we migrate the Vision Builder program to LabVIEW.

Things we need:
-1 Computer with Vision Builder and LabVIEW
-1 Webcam

First of all, we open Vision Builder an we make a states machine. There, we create a simple program where we read the dimensions of an usual rectangle: we adquire an image, we convert it to a greyscale image, we locate the borders of the image to get a point of reference and then, we measure the high and the length. Then, we compare them to see if the dimensions may be right. If they are right, we finish the program, else, we go to the other state, where we repeat the first pass, but turning all the ROIs 45 degrees. Then, we print the correct result on the screen.

Object Recognition

The aim of this practice is to recognise objects using artificial vision with Vision Builder.

Materials we need:
-1 Computer with Vision Builder
-1 Webcam
-Some objects to recognise (clips, beans...)
-A difuse light

The first thing that we have to do is to put some objects to identify over a difuse light. Then, we will put the webcam over it and we open Vision Builder. Once there, we start the adquisition of images, we convert the image to a greyscale image taking from it the red pannel. Then, we will detect objects and then, we will compare those objects to a database created by us.

This process is similar to the OCR process. We click on Classify Objects and we modify the Threshold to find the objects. Then, we edit the classifier file.

OCR/QR

This practice consists on read text and QR code (Quick Response code) in Vision Builder.

For this practice, we need:
-1 Computer with Vision Builder installed
-1 Webcam
-1 Paper with a QR and text on it

The first thing that we have to do is to go to Read/Verify Text and click there.

Capacitor

This practice consists on measuring the charge and discharge of a capacitor and to compare it with it's theoretical result, using a DAQ (Data Adquisition device) and LabVIEW.

Materials needed:
-1 Computer with LabVIEW
-1 NI DAQ 6008
-1 Relay
-1 Capacitor (100µF)
-1 Transistor
-1 Diode
-3 Resistors (1 of 10k and 2 of 2700 ohms)

The first thing that we have to do is to do the theoretical calculations. We will calculate theorically how much time does the capacitor takes to be charged and discharged.

First of all, we have this formula, which represents the change of the voltage of the capacitor in function of the time:

Where:

Graph of Temperature

This practice consists on introduce in a graph the temperature of a day, read from a database. Moreover, we can modify the temperature of every hour of the day.

Materials we need:
-1 computer with LabVIEW and Microsoft Access

To do that, the first thing that we have to do is to create a database with the temperature of every hour in a day. In my case, do don't invent it, I took the values from this page:
http://www.accuweather.com/es/es/santander/306949/hourly-weather-forecast/306949?hour=46

Then, we have to introduce these values inside a database:

PT100

This practice consists on measuring temperature using a PT100, an arduino and LabVIEW.

Things we need:
-1 Computer with LabVIEW
-1 PT100
-1 Power supply
-6 Resistors (2 of 1k, 1 of 100 ohms and 3 of 1 ohm)
-Wires
-1 Arduino

To make this practice, the first thing that we have to do is to design the circuit that we will use to read the temperature. there, we will use the arduino to read the difference of voltage between A and B, like a Wheatstone Bridge.

Arduino

This practice consists on, using LabVIEW and Arduino, to make a program where:
-If I press the button D12, I read the value of the potentiometer A0.
-If I press the button D8, I read the value of the potentiometer A1.
-If I press the button D7, I read the value of the temperature.
-If I press the button D4, I change the value of a LED.

To do it, we will use the shield of MSE Bilbao. In this picture we can see the shield with the names of the parts that we will use:

In LabVIEW, we will create an VI like this. On the right side we can see a picture of the shield, the actions of the buttons and a button that when you press it, it appears a pop-up that tells the instructions of the program. On the left side of the VI we can see a button to stop the program an the value measured.

RTC

The aim of this practice is to simulate a Real Time Clock (RTC) in Proteus.

The first thing that we have to do is to make this electronic circuit in Proteus:

To don't focus all my efforts in unnecesary things, most of the parts of this circuit are explained in the previous I2C practice, so you can find out what are them in this link: http://marcoselectronicblog.blogspot.com.es/2016/05/temperature.html

The main difference with the previous practice is that here we use the DS1307 RTC:

Temperature

The aim of this practice is to use Proteus to simulate a digital thermometer with a DS1621 and print the temperature on a LCD screen.

To do that, we open Proteus in our computer and we create the next electronic circuit:

Where we have the next parts:

Blink

The aim of this practice is to switch ON and OFF two LEDs with our Raspberry Pi using Python3.

Materials:
-1 Raspberry Pi
-2 LEDs
-2 Resistors (1kΩ)
-Wires

To do that, first, we have to connect a LED and a resistor to the pins 17 and 27 of the Raspberry Pi. The end of the circuit will be in a pin of GND, also in our Raspberry Pi. We can mount it in a protoboard.

In the Raspberry Pi, we will open Python3 and we will write this code:

PCB: CNC

This is the second part of the practice of the PCB. In this part, our aim is to do a PBC using a CNC. A CNC Milling Machine (Computer Numerical Control). It's a machine where you put a cupper board and it mills it with the sape and the holes that you have introduced on it.

Materials:
-1 CNC
-1 Computer with Proteus
-6 Capacitors of 100nF
-1 Capacitor of 1µF
-1 Max232
-1 Power Jack DC
-1 DB9 Connector
-Male connectors for PCB

The first thing that we have to do is to go to the first part of this practice, where we finish the layout of the board in Proteus.

Once there, we will create our Gerber and Excellon files.

PCB: Acid

In this practice, we have to do a PCB (Printed Circuit Board). To do something with that board, we will create a TTL-RS232 adapter.

Things we need:
-1 Computer with Proteus installed
-1 Printer
-Onion Paper
-1 Negative Photosensitized Plate
-Etching (Nitric Acid): HNO₃
-Hydrogen Peroxide: H₂O₂
-Water: H₂O
-Latex Gloves
-Gas Mask
-1 Guillotine
-1 Contact Printer


In this practice, the first thing that we have to do is to switch on our computer and open the program Proteus. Once there, we will design the electronic circuit that we want to make in our board. Following the instructions of the datasheet of the max232, we will do it like this:

Stepper motor with Raspberry Pi

In this practice, we have to control a stepper motor with our Raspberry Pi.
Things we need:
- 1 stepper motor
- 1 controler for the stepper motor
- 1 raspberry pi
- Wires

What we have to do in this practice is to connect all the wires on their possitions:
-The pins of the controller of Vcc and GND go to the same names, in the raspberry.
-The pin 1 of the controller go to the pin 11 of the raspberry (GPIO17).
-The pin 2 of the controller go to the pin 15 of the raspberry (GPIO22).
-The pin 3 of the controller go to the pin 16 of the raspberry (GPIO23).
-The pin 4 of the controller go to the pin 18 of the raspberry (GPIO24).

In our case, we will use the motor in Full Step, so this is the order of the coils that we are going to use:
D C B A
1  0  0  1
1  0  1  0
0  1  1  0
0  1  0  1
To increase the precision, the coils of our stepper motor are divided inside in 8 coils each one. Those coils are called "poles". This makes 32 steps needed to do a lap. Moreover, the motor has a reduction gear of 1/64 to increase even more the precision. This makes 32*64=2048 steps to do a complete turn.

Here, we can see the full code with comments:

Note about exercise 9 from "type range" in Python Programs

In the exercise 9, in the exercises type range(), there is a part where you need a mathematical formula that you may not know. When i looked at the solution of the exercise (http://www.mclibre.org/consultar/python/ejercicios/ej_range_soluciones.html), i found:

inicial2=inicial//paso*paso+paso

Ok, but... what the hell was that??
To understand it, searched it for all over the web and after hours searching for it, i got tired because of the lack of positive results and I decided to take a paper and a pen and start doing the best thing I can do: thinking.

After two hours in front of a paper, I found the solution: The test to know if you have solved good the division!!!

I found a relation between that strange formula and the test of the division:

inicial//paso*paso+paso <=> D//d*c+c (Dividend/divisor*cocient+cocient)

That's where that formula comes from, in case that you are interested on it. Else, you may just need the formula to solve the problem. This entry of this blog is only to curious people like me who want to understand this better, like me.

If you still don't understand it well and you want to understand it better, you can ask it in the comments and i'll try to explain it the best i can!