Final Project

The path to the final project

I started out by designing a 3D model of a water jet turbine

I made a turntable rendering to show the turbine from all sides

Click on the picture and move the mouse left and right to turn the drawing

Double click to see the water turbine in full screen

I then decided to design and make a logo for my Water turbine final project

Pressed my Water turbine logo on a T-shirt

3d print of the final project

Water Jet Turbine

The prop was printed separatly and attached to the model

Final project schematic

Here is the schematic of the water turbine that i designed to get a overview of the components i need and how to connect them all together.

Bracket

In week 16 - Moulding and Casting I designed a pracket that will be connected to my Water Turbine

Here is a rendered image of the Water Turbine with the bracket .

Components of the project

1) Voltage stepdown

For voltage stepdown i will use Vellman VMA404 adjustable voltage step down module

• input voltage: 3 to 40 VDC
• output voltage: 1.25 to 35 VDC
• max. output current: 2.5 A
• chip: LM2596S
• dimensions: 49 x 26 x 12 mm (1.14 x 1.02 x 0.47 " )

2) LCD display

My plan is to use a i2c 2004 LCD display screen for information on the charging and speed

• I2C Address: 0x20-0x27(0x20 default)
• Number of Characters: 20 characters x 4 Lines
• Blue LED backlight with white char color
• Adjustable contrast
• Supply voltage: 5V
• Interface: IIC/TWI
• View direction: Wide viewing angle
• Dot size: 0.55 x 0.55 mm / Dot pitch: 0.60 x 0.60 mm
• Character size: 2.96 x 4.75 mm /Character pitch: 3.55 x 5.35 mm
• Size: 98x60x24mm
• Weight: 75g

3) WiFi module

I want to be able to monitor my charging with a app on my cell phone remotely so i will use a ESP8266 WiFi module

What is ESP 8266 module

ESP8266 is a wifi SOC (system on a chip) produced by Espressif Systems . It is an highly integrated chip designed to provide full internet connectivity in a small package.

ESP8266 can be used as an external Wifi module, using the standard AT Command set Firmware by connecting it to any microcontroller using the serial UART, or directly serve as a Wifi-enabled micro controller, by programming a new firmware using the provided SDK. The GPIO pins allow Analog and Digital IO, plus PWM, SPI, I2C, etc. This board has been around for almost a year now, and has been used mostly in IoT contexts, where we want to add connectivity for example to an Arduino project. A wide adoption has been facilitated by the very modest price, ranging from 2.50 to 10 USD depending on the features offered by the manufacturers.

Technical information

• 802.11 b / g / n
• Wi-Fi Direct (P2P), soft-AP
• Built-in TCP / IP protocol stack
• Built-in TR switch, balun, LNA, power amplifier and matching network
• Built-in PLL, voltage regulator and power management components
• 802.11b mode + 19.5dBm output power
• Built-in temperature sensor
• Support antenna diversity
• off leakage current is less than 10uA
• Built-in low-power 32-bit CPU: can double as an application processor
• SDIO 2.0, SPI, UART
• STBC, 1×1 MIMO, 2×1 MIMO
• A-MPDU, A-MSDU aggregation and the 0.4 Within wake
• 2ms, connect and transfer data packets
• standby power consumption of less than 1.0mW (DTIM3)

4) Charging control module

To regulate my charging i will use a charging board that keeps a constant 12V charge so my battery is protected from a variable current from the water turbine

XH-M603 Charging Control Module Digital LED Display Storage Lithium Battery Charger Control Switch Protection Board 12V

4) RPM sensor

To sense the RPM of the water turbine i will use A1302KLHLT-T LH SOT 23W Hall effect sensor

The hall effect, in short, is a relationship between electric and magnetic fields through a semiconductor that allows electricity to flow when a magnetic field is applied within the vicinity of a given hall sensor. In our case, we will be using the SOT 23W Hall effect sensor, which is a unipolar sensor. Unipolar sensors are great for scenarios where only one pole of magnet is needed. This allows us to stick a magnet to a moving object and as it cycles through its rotation, each time it passes the hall sensor, the hall sensor registers its passing and we can say that one period has been completed.

In week 6 i designed a board with a Hall sensor that i connected to a Attiny 1614 board that i also made.

Packaging

I have started designing the main control box of the turbine. It will house all the electrical components and will be 3d printed

Dimensions of the the control box

Main Control Board

The board I made to control all the elliments will be a computer board with ATtiny 1614 that i can connect to all of the input and output devices

Here is the schematic of the ATtiny 1614 board that i made in Kicad

MESURE SPEED

My final project is a water turbine and that is why I decided to try to mesure the speed of my motor with a Hall effect sensor.

A Hall effect sensor is a device that is used to measure the magnitude of a magnetic field. Its output voltage is directly proportional to the magnetic field strength through it. Hall effect sensors are used for proximity sensing, positioning, speed detection, and current sensing applications.

Hall effect sensor

I will also make a input device board with a hall sensor and connect it to my new multifunctional board

Found this Arduino schematic of a Hall affect setup that will help me to make my input device board

I managed to get my hands on a A1302KLHLT-T LH SOT 23W Hall affect sensor. Here is the data sheet

From the data sheet we can see how to correctly connect it to the ATtiny 1614 board

Kicad schematic of the Hall effect sensor board

Here is the Hall affect after I exported it from Inkscape. Files read to be cut out in the Roland SRM-20

Finished soldering and connecting my Hall Affect sensor board. .

I will use this Arduino code to make the led blink when magnet passes the Hall effect sensor and it will also give a magnetic strenght reading to the computer

When I was connecting my sensor board I noticed that the voltage of my Hall Sensor was 3.3 volt but my board design was using 5v. To get the correct voltage i connected to the 3.3 v output on my Ardoino board.

The moment of truth will it work!!!! Will the light turn on when the magnet approaches

It worked !!! I have never been so happy to see a light turn on...

When I bring the magnet close to the sensor I get a High number of almost 600. When the magnet is far away the reading is about 300 and if I flip the magnet around and bring it close to the sensor the reading is somewhere around 30

Mesure speed

Next step is to set try to sense the speed of a computer fan that has a magnet attaced to one of the blades

The unipolar hall sensor can function as a tachometer. I will demonstrated a simple experiment using a 5V blower fan, hall sensor, and neodymium magnet attached to the fan. The setup allowed us to print out values for the approximate RPM of the fan, which can give us a more accurate idea of the flow rate of the fan.

// digital pin 2 is the hall pin
  int hall_pin = 2;
  // set number of hall trips for RPM reading (higher improves accuracy)
  float hall_thresh = 100.0;
  
  void setup() {
    // initialize serial communication at 9600 bits per second:
    Serial.begin(115200);
    // make the hall pin an input:
    pinMode(hall_pin, INPUT);
  }
  
  // the loop routine runs over and over again forever:
  void loop() {
    // preallocate values for tach
    float hall_count = 1.0;
    float start = micros();
    bool on_state = false;
    // counting number of times the hall sensor is tripped
    // but without double counting during the same trip
    while(true){
      if (digitalRead(hall_pin)==0){
        if (on_state==false){
          on_state = true;
          hall_count+=1.0;
        }
      } else{
        on_state = false;
      }
      
      if (hall_count>=hall_thresh){
        break;
      }
    }
    
    // print information about Time and RPM
    float end_time = micros();
    float time_passed = ((end_time-start)/1000000.0);
    Serial.print("Time Passed: ");
    Serial.print(time_passed);
    Serial.println("s");
    float rpm_val = (hall_count/time_passed)*60.0;
    Serial.print(rpm_val);
    Serial.println(" RPM");
    delay(1);        // delay in between reads for stability
  }
  

 

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Designing the mould

For this week I wanted to design and make a moulding cast that I could use for my Final Project.

So I decided to make a mount for my Turbine. This item will stear the turbine in line with the current and make it steady under water

Started by drawing a wireframe of the turbine mount

After drawing the outlines and tweaking them around a bit I got the shape I was happy with and then made a 3d model from the outlines.

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Making the mould

After I finished drawing the bracket that I was going to mount to my Turbine. Then the next step was to make mould around it

Mould

Made a two sided mould with cutouts to stear the two sides correcly in place

Made also one poaring hole 15mm wide and one 6mm air hole to let trapped air out when making the item

Here are both sides of the finished mould

Mould ready for Milling

Was not able to finish my mould this week because I did not have the nessasary materials to work with.

I will travel next week to Fablab Akureyri in North of Iceland to finish my Mould :-)

Here below is the file that I made in Rhino

turbine Bracket Mould.3dm /

Final project video

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Experiment

Experimenting on how Electric motors work.