I have started thinking about producing some Kiteboarding T-Shirts and perhaps start a small Kite Wear Company about six months ago. As a software developer, I am comfortable with computers and I thought I could do the designs myself, after watching some Illustrators Tutorials on the internet. I quickly realized that I was completely wrong. I have no skills neither talent to create artistic designs. Thus, I went to the Auto Tracing Tools, such as Corel Trace and some others.
Their result were even worse than my manually generated designs.
I had no choice, if I wanted to produce high quality t-shirts, I would have to hire a professional designer.

I did some budged estimates and I almost gave up due to the high cost to produce a vector design. It was about U$100,00.  To be honest it is not a that expensive for a established company. However, I hadn’t a established company, I was not even thinking about creating a company. I was willing to produce small quantities of 5 or 10 different designs. In this case, the U$100,00 for images would be too expensive.
In order to produce T-shirts with good quality and an affordable price, we have to find and talented and affordable  designer and a base image to start.

Requirements

This paragraph is to explain what are the requirements involved in the life-cycle of the t-shirt production, such as tools, prototyping, vectorization, printing, colors, fabric types and cuts.

- Basic understanding of vectorization tools like Adobe Illustrator or Corel Draw
- A good designer capable of producing vector images
- A way to prototype before producing large quantities
- A good silk screen company
- A good fabric provider

Tools

You can’t use regular images like JPGs to print using silk-screen, this image needs to be converted to the vector format.
The Silk Screen process consists in the separation of every color in an image and printing them one after the other. so, it requires you to provide a way to print every color in separete
There are some tools that can convert an image to vector automatically, such as Coral Trace, but unfortunately the result is almost always with low quality.

I prefer to use Adobe Illustrator because it is user friendly, but keep in mind that most of the silk-screen companies only have Corel.

Finding a good designer

I have no doubt that hiring a consultant designer is the best way to get exactly what you want and with high quality. However, professional designers are usually expensive and not suitable for small projects. I have found consultants charging an average of U$100,00 per job. By job I mean, a complete T-shirt design without review limitations.
So, I started browsing the web for cheap alternatives, as always. In this journey I have passed through several designers, charging from U$5,00 to U$40,00. Most of them are natural from India, China and Russia, Pakistan, etc.

- PGConversion.com:
These guys are amazing. They charge U$26,00 to convert and JPG to vector and U$40,00 to convert and JPG and add their creativity to a complete T-shirt design. They also offer unlimited reviews in this price.
My first try with them was to convert and picture to a vector and that was the result after 2 or 3 reviews:

Before

After

In a second try I gave them a more complex image to be converted and asked (and payed more) them to use their creativity. It took about 20 reviews, has cost U$40,00 but the resulting vector was pretty good.
Although the result is very good, it is a JPG to Vector conversion as usual, without many creativity. I had to provide all the elements in the picture:

Base image

First version. (Nice, but too many colors for a T-Shirt)

Final version after about 20 reviews.

- RentACoder.com:
ReantACoder is a auction web-site for developers. You can offer you skills and hire skilled developer and designers. They provide a very good interface to add your requirements and instructions on how to get them done well and without frustration.
The main advantage of RaC is the price. You can get vectors as low as U$5,00. Off course you get what you pay for.
I have asked for samples in all my auctions. If you don’t ask for a sample you might get an “auto-trace’d vector”.
It worth the try, specially if you image is simple.
The conversion below has a cartoons style and its cost was only U$10,00.

Before

After

Prototyping

The Silk Screen companies usually require you to print a minimum quantity of 20 units. Imagine if there is a small mistake in the entire production. You would end up with 20 brand new pijamas.
Fortunately there are two good ways to prototype. Imaging prototyping and with a Inkjet printer.

The imaging prototyping is simple as putting your art over a clena T-shirt picture in your preferred image editor. You can use this clean pictures: http://www.flickr.com/photos/frankllin/tags/tshirtbackground/ (These are not the best T-shirt color in the world. I would appreciate you someone could provide me other colors)

After that you can print a sample in a  T-shirt Printer and avoid the most common mistakes. There is a “T-Shirt Kiosk” in a shopping mall closer to my home, which has a Brother GT-541 printer and charges U$12,00 per t-shirt. The result is usually poor, lacks for the white color and the cost is slightly higher than Silk Screen, but the advantage is that you can print a single unit before sending your artwork for production.

These are the mistakes that I look when prototyping:

• Position and alignment of the image.
• If the combination of colors fits well in the fabric.
• If my art has more details than a printing can handle.

Finally,  a good Silk Screen Company has to provide a sample. If they don’t provide you samples, find another company. Believe me, without a sample you build a collection of pijamas.

Printing with Silk Screen

A t-shirt is generally printed with silk-screen, which requires every color to be printed separetelly. that is why we need to use vectors and not flat images, so the colors can be separated and printed one by one.

ps. I write this blog in English willing to practice my Eglish writting skills. I will appreciate if you post a comment either with fixes or pieces of advice.

This post is a copy of the Original post on EBay. I am replicating it here because ended items on Ebay are not indexed by Google, the author’s page is written in Chinese and doesn’t contains the Source code. If you are the author and you are obset with this, please get in touch.

This Potentiometer module is a simple knob that provides a variable resistance, which we can read into the Arduino board as an analog value. By turning the shaft of the potentiometer, we change the input signal to analog pin.

Building interactive work is as easy as piling bricks, just plug it to our Arduino Sensor Shield with a buckled cable, and make it looks professional and neat.

The code below controls frequency of on and off of a LED light ,

int potPin = 4;    // pin for potentiometer
int ledPin = 13;   // pin for LED
int val = 0;       

void setup() {
  pinMode(ledPin, OUTPUT);  // state ledPin as an OUTPUT
}

void loop() {
  val = analogRead(potPin);
  digitalWrite(ledPin, HIGH);
  delay(val);
  digitalWrite(ledPin, LOW);
  delay(val);
}

PotentiometerSensor Source code

Original post on EBay

Based on LDR (Light Detect Resistor), this Light Sensor Module measures the environment light intensity and input data to Arduino through the analog IO port of Sensor Shield. Great tool for light following robot, gardening system or home alert system.

Building interactive work is as easy as piling bricks, just plug it to our Arduino Sensor Shield with a buckled cable, and make it looks professional and neat.

Based on thermistor, this Temperature Sensor Module measures the environment temperature and input data to Arduino through the analog IO port of Sensor Shield. Great tool for gardening projects, home alert system etc.

Building interactive work is as easy as piling bricks, just plug it to our Arduino Sensor Shield with a buckled cable, and make it looks professional and neat.

A simple program below converts data from Temperature Sensor Module to Fahrenheit and displays it in Serial Monitor. This function utilizes the Steinhart-Hart Thermistor Equation to convert “Thermistor Resistance” to “Temperature in Degrees Kelvin.” For details, please read here.

#include

double Thermister(int RawADC) {
double Temp;
Temp = log(((10240000/RawADC) - 10000));
Temp = 1 / (0.001129148 + (0.000234125 * Temp) + (0.0000000876741 * Temp * Temp * Temp));
Temp = Temp - 273.15;            // Convert Kelvin to Celcius
return Temp;
}

void setup() {
Serial.begin(115200);
}

void loop() {
Serial.println(int(Thermister(analogRead(0))));  // display Fahrenheit
delay(100);
}

The magnetic reed switch module is a wonderful tool for designers who would like to turn a circuit on and off based on proximity. A digital “high” value is given when approached by magnet in around 1 inch (depends on strength of the magnet)

Building interactive work is as easy as piling bricks, just plug it to our Sensor Shield with a buckled cable, and make it looks professional and neat.

Building interactive work is as easy as piling bricks, just plug it to our Sensor Shield with a buckled cable, and make it looks professional and neat.



Example code to turn off LED when approached by a magnet:
int ledPin = 13;               // choose pin for the LED
int inputPin = 2;               // choose input pin (for magnetic switch)
int val = 0;                   // variable for reading the pin status

void setup() {
  pinMode(ledPin, OUTPUT);      // declare LED as output
  pinMode(inputPin, INPUT);     // declare magnetic switch as input
}

void loop(){
  val = digitalRead(inputPin);  // read input value
  if (val == HIGH) {            // check if the input is HIGH
    digitalWrite(ledPin, LOW);  // turn LED OFF
  } else {
    digitalWrite(ledPin, HIGH); // turn LED ON
  }
}

Original post on EBay

Example code to read data from the sensor:

int sensorPin = 2;    // select the input pin for the sensor
int ledPin = 13;   // select the pin for the LED
int val = 0;       // variable to store the value coming from the sensor

void setup() {
  pinMode(ledPin, OUTPUT);  // declare the ledPin as an OUTPUT
  Serial.begin(9600);        // initialize serial communication with computer
}

void loop() {
  val = analogRead(sensorPin);    // read the value from the sensor
  Serial.println(val);          // send it to the computer (as ASCII digits)
  digitalWrite(ledPin, HIGH);  // turn the ledPin on
  delay(val);                  // stop the program for some time
  digitalWrite(ledPin, LOW);   // turn the ledPin off
  delay(val);                  // stop the program for some time
}

Original Ebay post.

This is a small buzzer for the Sensor Shield. It creates different noises based on the different frequency of I/O toggling. All you need to do is to plug in the buzzer module to sensor shield, and tell the function which pin you’d like to use, the frequency you want to hear, and the duration to play that frequency.

Building interactive work is as easy as piling bricks, just plug it to our Buzzer Module with a buckled cable, and make it looks professional and neat.

Example code to play melody:

int BuzzerPin = 9;
int length = 15; // the number of noteschar notes[] = "ccggaagffeeddc "; // a space represents a rest
int beats[] = { 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 4 };
int tempo = 300;
void playTone(int tone, int duration) {
for (long i = 0; i < duration * 1000L; i += tone * 2) {
digitalWrite(BuzzerPin, HIGH);

delayMicroseconds(tone);

digitalWrite(BuzzerPin, LOW);

delayMicroseconds(tone);

}

}

void playNote(char note, int duration) {

char names[] = { 'c', 'd', 'e', 'f', 'g', 'a', 'b', 'C' };

int tones[] = { 1915, 1700, 1519, 1432, 1275, 1136, 1014, 956 };

// play the tone corresponding to the note name

for (int i = 0; i < 8; i++) {

if (names[i] == note) {

playTone(tones[i], duration);

}

}

}

void setup() {

pinMode(BuzzerPin, OUTPUT);

}

void loop() {

for (int i = 0; i < length; i++) {

if (notes[i] == ' ') {

delay(beats[i] * tempo); // rest

} else {

playNote(notes[i], beats[i] * tempo);

}

// pause between notes

delay(tempo / 2);

}

}

This is a copy of the original post on Ebay
Arduino Sensor Shield V4.0 allows you to connect to various modules like sensors, servos, relays, buttons, potentiometers……….just plug & play.

Each functional module has buckled port with VCC, GND and Output, which has corresponding port on the Sensor Shield, connected with a plain 2.54mm dual-female cable you may start playing already. Buckled brick cables are like cement for bricks, make the connections easier, secure and more professional looking.

1. Buckled Analog Port

Handy, solid connection to 6 Analog inputs with VCC/GND

2. Digital IO port

13 ports prepared to digital modules or servos

3. Analog IO Port

2.54 grid male pin header connections

4. Buckled Communication Port

Selectable between I2C and UART

Original post on Ebay

The Infrared Reflectance Sensor Module carries a single infrared LED and phototransistor pair in an inexpensive, tiny module that can be mounted almost anywhere and is great for obstacle detection of robot and home alert system. The optimal sensing distance is within 50cm (20 inches).

Building interactive work is as easy as piling bricks, just plug it to our Arduino Sensor Shield with a buckled cable, and make it looks professional and neat.

The Infrared Reflectance Sensor Module simply gives a digital signal when it detects infrared reflection from a person or object, so the code is exactly as the one we would use for a pushbutton. Please be noted that, when reflection is detected, it gives a “low” value.

int ledPin = 13;       // choose pin for the LED
int inputPin = 2;      // choose input pin (for Infrared sensor)
int val = 0;           // variable for reading the pin status

void setup() {
  pinMode(ledPin, OUTPUT);   // declare LED as output
  pinMode(inputPin, INPUT);  // declare Infrared sensor as input
}

void loop(){
  val = digitalRead(inputPin);  // read input value
  if (val == HIGH) {            // check if the input is HIGH
    digitalWrite(ledPin, LOW);  // turn LED OFF
  } else {
    digitalWrite(ledPin, HIGH); // turn LED ON
  }
}








red light at the back to show presence of object 

This post is a copy of this Arduino Relay on Ebay. I am replicating it here because ended items on Ebay are not indexed by Google, the author’s page is written in Chinese and doesn’t contains the Source code. If you are the author and you are obset with this, please get in touch.

Appliances with high voltage and current can’t be controlled by the Arduino digital IO ports directly, we need a relay to solve this problem. The Arduino Relay module allows Arduino Sensor Shield with digital outputs to control larger loads and devices like AC or DC Motors, electromagnets, solenoids, and incandescent light bulbs.

-Featuring Omron G5LE relay-Switching capacity of 250 Vac / 5 Vdc -LED indicator display the output status of the Relay Module-Compatible with our Arduino Sensor Shield



-Connect to external appliance

-Connect to digital IO port of Sensor Shield

-Not neccessary when using Sensor Shield, only for use directly with Arduino or other MCU

WARNING: When working with this device, you will be dealing with ~120V / ~220 AC. This is considered HIGH VOLTAGE, which as many know, can be lethal. Be careful when working with high voltage; NEVER work on this when it is plugged in. Make sure all connections are how they should be, and verify that they are fully insulated and won’t short each other out, or you could cause a fire. Also, be aware of what is going on around you, be alert, and never work on with high voltage if you feel you can’t devote enough concentration towards what you are doing. And lastly, if you ever have to service the connections inside this device, ALWAYS unplug it before doing so.

In this experiment, we will need the Arduino Duemilanove, Sensor Shield, Relay module, LED module, Button Switch module and a 220V or 110V desk lamp. A relay is an electrically controlled mechanical switch. Inside the little plastic box is an electromagnet that, when energized, causes a switch to trip.

Example of using Relay module to switch a household desk lamp

1. Stack the Sensor Shield onto the Arduino Duemilanove, and connect the modules with our specialized cables at the buckled end.

2. On the other end of the cables, connect the Relay module to digital pin 8, LED module to digital pin 13 and Button Switch module to digital pin 2.

3. Now, let’s test the arduino connection before connecting the appliance. Copy the code below and upload to the arduino.

int switchPin = 2;
int relayPin = 8;
int ledPin = 13;
int value = 0;

void setup() {
 pinMode(switchPin, INPUT);
 pinMode(relayPin, OUTPUT);
 pinMode(ledPin, OUTPUT);
}

void loop() {
 value = digitalRead(switchPin);
 if (HIGH == value) {
  digitalWrite(relayPin, HIGH);
  digitalWrite(ledPin, HIGH);
 } else {
  digitalWrite(relayPin, LOW);
  digitalWrite(ledPin, LOW);
 }
}

When you click the push button, the relay will give out a very satisfying clicking sound, which means it is switching the appliance.

4. My desk lamp is in UK wiring system without earth (ground), so you only see two wires in the cord. Cut the hot (live) or neutral wire in half and expose metal in 5mm. Here is a table to show the color of each wire:

5. In the relay module, we will only use the wire contacts on the left (the one above the “Relay” logo) when we connect it with the Sensor Shield. There are 3 wire contacts. We can use either set A or set B as shown in the picture, just make sure the middle one is used.

6. Screw the two wires into the contacts. Make sure no metal wire is exposed outside of the plastic for safety.

7. This last step is easy, plug the socket of the appliance and you can control the on/off by the arduino now.