Bats Have Feelings Too

Sonar garment to assist the visually impaired with navigating the built environment. Made from Lilypad main board, LV-MaxSonar ultrasonic range finder and a LilyPad vibeboard. The range finder can be set to locate a solid object X distance in front of the user and turn the vibeboard on alerting the user to stop before walking into a solid object.

This project was inspired by attending the unveiling of the award winning facilities for Anchor Center for Blind Children designed by star architect Maria Cole. During my visit one of the former students came up to speak with me because she could 'see' what I was wearing (a confetti fabric coat) and she too wanted to design clothes. Just goes to show ya never know where the next project is coming from!

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Eric from Talk2MyShirt wrote a fatabulous review of this project! Thanks!!
See it here:
http://www.talk2myshirt.com/blog/archives/1387

For the garment you can use something you have, go buy something or even DIY!

I went to a local thrift and found a cute woman's light weight jacket.
I made sure the garment had some specific design elements to support my over all design concept, allowed me to 'hide' the electronics and required as little sewing as possible.

These design elements are:
Placket in between the shoulders
Front facing all the way around the coat opening that was held in place with tailor tacks.
Back facing also held in place with tailor tacks.

Stuff I had stuffed in my supply drawer:
Conductive thread
Needles
Thread to match your project
USB cord
USB link for the Lilypad
Tailors chalk
Tape
Scissors
Alligator clips
Fray check
Magic marker
Paperbacked Iron-on Adhesive

Stuff I had to purchase:
LilyPad Arduino Main Board

LilyPad Power Supply

LilyPad Vibe Board

Maxbotix LV-EZ4

You can find parts elsewhere, or even DIY.
I like to support my local shop, plus Nate is super nice, hires a fantastic staff of sparkies and he goes to Burning Man

Where will the guts be placed?
What do Bats look like?
How will all of the hardware get connected?
Ultimately, what is the easiest way to execute this project and is that the best method?

I use pins, tailor's chalk and paper to plan out the circuitry and aesthetics of the garment.
Take your time with this step.
Experiment.
Experiment.
Try the garment on.
Experiment some more.
Step away.
Re-evaluate.
Then
Mark your sewing lines with tailors chalk, tape your computer parts in place
and
think some more.

Some tips:
The power supply is heavy and critical to the longevity of your project. Place it somewhere easily accessible, durable and stable. The more movement this piece has the more likely the project will develop a short circuit.

The power supply and the main board want to be near each other. A robust circuit will be a short distance. A short distance decreases the possibility of a short circuit. Please remember BOTH sides of the fabric can be used!! Think in all dimensions for a groovalicious result.

Stretchy fabrics lead to stretchy traces which generally result in short circuits.

Once I made a decision on what Bats look like I was ready to land the Bats on the jacket.*

This is the series of steps I took :
Make Bat templates.
Fuse the iron-on adhesive on your fashion fabric.
Trace your Bats on to the paper of the iron-on adhesive.
Cut the Bats out.
Locate Bats on garment and pin in place.
Try the garment on and make necessary adjustments.
Stop and think........after the next step it's tricky to change the design.
Put garment on ironing board.
Preheat iron.
Peel off the paper backing on a Bat.
Position Bat on the garment.
Pin the Bat in place.
To protect your fashion fabric place a piece of paper over your Bat.
Fuse the Bat in place by ironing over the paper.
Check to be sure the Bat is completely attached to the garment.
Viola! Bats Bats everywhere!

• Please Note: The Bats serve no technical purpose for this project, they're just groovalicious. You can make any shape. design or nothing at all.

Fast and Easy..

Clip the metal extensions on the back of the power supply.
Tailor tack the power supply in place - (tailor tacking is just small stitches with regular thread. think of it as a fabric paperclip).

With conductive thread sew the + petal of the power supply down to your garment.
Make several passes thru the + hole until you can no longer fit the needle thru.

Sew the + trace to the + petal on the Lilypad.

Again pass the needle thru the + petal on the Lilypad until you can no longer fir the needle thru.

Then sew back along your trace towards the power supply.
This will give you a more robust connection as well as allow you to knot your thread a place where it will be less likely to short circuit.

Knot your thread.

Place a drop of fabric glue on the knot.

Take a break!

Once the glue is dry then clip the thread tail.

Repeat for the - connections.

Using a multimeter, test the traces for short circuits.


Tips
I would suggest gluing velcro to your power supply and to the fabric. With this method the power supply is still removable, but held tightly in place. Place the pricky side of velcro on the power supply and the soft side of the velcro on the garment. This way if you wear the garment without the battery pack you wont stick to anything.

Do everything you can to reduce the possibility of a short circuit.
Use short neat stitches.
Place fabric glue on the final stitches to hold them in place.
And plan ahead...having to rip out your traces is depressing, but not deadly.

Right here on 'ibles there are lots of examples and directions on sewing the power supply and Lilypad. Just do a search to learn more more more.

The final location of the vibe board ended up on the outside of the collar.
Sew - on the vibe board to the - on the main board.
Sew + on the vibe board to the #13 digital pin on the main board.

Using a multimeter test for a short in your traces.

Depending upon your design scheme you may want to make the Tubes of Conductiveness (TofC) or you may want to directly sew the conductive thread to your garment.

This step is a design choice.
If you want to skip it please go on to the next step.......

Make three Tubes of Conductiveness

By using the TofC you don't have to sew all the way from the Maxbotix which will be located on the front of the jacket all the way around to the main board. The TofC are draped in the interstitial space between the facing and the fashion fabric and then tailor tacked in place.

And

The TofC help prevent short circuits. :)

But if you want to sew or match a certain design look, please go ahead and skip this step.

Attach the Maxbotix range finder to the coat using project thread to the attachment holes.

Sew the + on the range finder to +5V on main board
Sew the GND on Maxbotix to the - on main board
Sew the AN on Maxbotix to analog pin 0 on the main board

Using your USB cable and USB link attach the Bats LilyPad to your computer.
Using Arduino software write the program so the Maxbotix will drive the vibe board.

I used the following program:

//Bats Have Feelings Too
//Wearable computer system to assist the visually handicapped
//Lynne Bruning November 2008

//output
int BUZZER_OUTPUT_PIN=13;

//intput
int RANGE_FINDER_INPUT_PIN=0;
int NUMBER_OF_UNITS_TO_SENSOR=42;
//change units to match your specific user and environment

void setup()
{
pinMode(RANGE_FINDER_INPUT_PIN,INPUT); //sets the range finder analog pin as input
pinMode(BUZZER_OUTPUT_PIN, OUTPUT); // sets the buzzer digital pin as output
digitalWrite(RANGE_FINDER_INPUT_PIN, LOW); // turns the buzzer off
digitalWrite(RANGE_FINDER_INPUT_PIN, HIGH); // turns the buzzer on

beginSerial(9600);
Serial.println("units");
}
void loop()
{
int val = analogRead(RANGE_FINDER_INPUT_PIN);
Serial.println(val); // units
if (val >= 0 & val <= NUMBER_OF_UNITS_TO_SENSOR)
{
digitalWrite( BUZZER_OUTPUT_PIN, HIGH); // turns the buzzer on
}
else
{
digitalWrite( BUZZER_OUTPUT_PIN, LOW); // turns the buzzer off
}
}

In the program you can change the ranger finder distance.
In the set up change the
NUMBER_OF_UNITS_TO_SENSOR
equal to what is appropriate for your user and their environment.

Now make it your own...
add more sensors
change the bats
or
put it in a hat.

Just imagine the possibilities.............