Those of us who have small garages know the frustration of parking a little bit too far in or a little too far out and not being able to walk around the vehicle. We recently bought a larger vehicle, and it has to be parked perfectly in the garage to walk around the front and back.

To appease my frustration I decided to design a device that would allow me to park in the exact spot every time. I love working with arduinos, leds, sensors, and nearly anything else electronic, so I knew from the start that it would probably end up as a contraption with an Arduino inside and a bunch of leds on the front!

I tried my best to document every step of this project well, but please note that it has some complicated, tight soldering; it probably shouldn't be your first project.

Step 1: You Will Need...

All of these materials are cheap and easily available. I'm not affiliated with any of these suppliers, they're simply where I bought the supplies.


  • 1x 2x4 - at least 8" long
  • 8x Philips Screws - Preferably 1" Long
  • 1x Power Supply - 5 volt, 850mA Here
  • 1x Arduino Pro Mini - 5 volt, 16MHz Here
  • 1x HC-SR04 Ultrasonic Distance Sensor Here
  • 12x Through-Hole Resistors - 220 ohm, 1/4 watt Here
  • 8x Green LEDs - 5mm Here
  • 4x Red LEDs - 5mm Here
  • 1x Tactile Pushbutton - 6mm Here
  • 3x Four Conductor Wire Sold by the Foot - 22 gauge Here
  • 1x Stranded Wire - 28 gauge Here


  • Wire Stripper
  • Bandsaw
  • Soldering Iron
  • Solder - I use 60/40 Rosin Core
  • Hot Glue Gun
  • Speed Square
  • Stick Glue
  • Philips Screwdriver
  • Pencil
  • Drill
  • 7/64" Drill Bit - this depends on the size of your screws
  • 3/16" Drill Bit
  • 1/4" Drill Bit
  • 1" Forstner Bit
  • Computer with the Arduino IDE Download Here.
  • FTDI Programmer Here
<p>Very low tech alternate solution, by my father-in-law:</p><p>Hang a tennis ball on a string from the garage ceiling. Locate it so that when you are perfectly parked, it just touches the windshield directly in front of the steering wheel.</p>
<p>Great idea the calibration. I will to study your code</p>
<p>Great job, this looks really useful! I especially love the way you calibrate it by pressing a button when your car's in the right spot. Perfect! I plan on using this idea for sure. Just as soon as I start learning Arduino.</p>
<p>Thank You! Arduino is really easy to learn, just read some of the example sketches and modify them! Adafruit tutorials are good, start on the last page and head toward the more complicated ones. </p><p>https://learn.adafruit.com/category/learn-arduino</p>
<p>Looks great! </p><p>How do you power it?</p><p>I'm looking to do the same, but embedded into my car, but if it's not possible, i think i will try your idea, but i don't have any <em>powersource</em> i my park.</p>
<p>Have a look at this waterproof sensor.http://www.ebay.com.au/itm/Waterproof-Ultrasonic-Module-JSN-SR04T-Distance-Transducer-Sensor-for-Arduino-/152234039330?hash=item2371db1822:g:Yu8AAOSwi0RX0RFN</p>
Those are cool! I've never seen anything like that before! They're just like the sensors in cars!
<p>The problem on your car is the water, rain or humidity. That sensor is not made for that !</p>
Use a USB car charger and cut the end off. https://www.google.com/search?ie=UTF-8&amp;source=android-browser&amp;q=micro+usb+car+charger <br><br>That's a great idea! Message me on Instructables if you need advice or have problems. I would be glad to help!
<p>Use your car power and a 12v to USB charger. About $1 on eBay.</p>
Cool idea! Maybe consider adding a timed delay to the calibrate function (with a slick LED count down) to allow you to get out of the way.
Thats a great idea! I thought there was some way to optimize that! I'll have to update the code!
<p>Use a LED strip for simpler wiring and greater colour possibilities.</p>
<p>Good Idea!</p>
Nice idea . <br>I think you can also add a buzzer to sound when it is too near.<br>Case is very neat.
<p>Very cool, i really like the calibrating idea too!</p>
Thanks! I previously made one where the distance was hard-coded; that was a pain!
<p>Recommend using a potentiometer to calibrate. Park where you want to set, then turn the pot to set. This way when you loose power it will remember setting when turned back on. Next fun experiment is to port it to an ATTINY. Cheaper, smaller and can run at a wide range of voltages.</p>
Apparently you didn't read my code! :-) I used EEPROM (arduino's internal memory) to save the distance. In my opinion, a button is less hassle than a pot would be.<br><br>Great idea with the ATTINY! I haven't played with them before, but now might be a good time to start!
Great project
<p>Cool idea! This would be very helpful!</p>
<p>Doesn't work on arduino uno or any other that I tried to change to in &quot;tools&quot;</p>
<p>Really? What error codes are you getting?</p>
<p>Sorry, I just realized I had a very simple issue in my code involving one letter being lowercase instead of capital!</p><p>Try downloading the &quot;Parking System.zip&quot; from the Instructable and uploading it to your Arduino again. Sorry for the trouble!</p>
<p>Another exellent instructable, good job!</p>

About This Instructable




Bio: I'm officially one of those people that spend almost all their time connecting wires, typing code, and doing other stuff people call 'boring.' I ... More »
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