Build a Robot Boat Using Water Bottles





Introduction: Build a Robot Boat Using Water Bottles

About: Hi, My name is Francisco Dias and I'm a student from Lisbon, Portugal. Have a look at my website:

This will show you how to build a robot boat from cheap and easy to use materials, I think it is also a good example of reusing water bottles.

I used two water bottles, polymorph plastic, two motors and propellers, tape, a box, a battery and a motoruino (Arduino clone designed to work with motors, servos and sensors).

Step 1: Materials Needed:

  • Two water bottles
  • Two simple dc motors
  • Two propellers
  • Isolating tape 
  • Box
  • Motoruino (or any other microcontroller and a h-bridge)
  • Battery

Step 2: Add the Motor and the Propeller to Each Bottle

  1. Take out the bottle cap and insert the motor on its mouth (you can use some insulating tape if you see that there is space between the motor and the plastic).
  2. Use polymorph to seal the bottle. If this is the first time you're using this material you may find these tutorials helpful:
  3. Attach the propeller

Step 3: Connect the Two Bottles

I used a polymorph extruded tube to pass give structure and pass the motors' wires and insulating tape just to support the box.

Step 4: Make the Electrical Connections

If you use a motoruino, you just have to connect the battery and motors' wires to the board. If you use a normal arduino you will have to use a shield or mount the h-bridge on a breadboard.

I used a SFR05 sonar, if you use it too, check this example: Ultrasonic Ranger

Step 5: Have Fun!

  1. Put the battery and the arduino at the box and mount it on the robot. 
  2. Upload the code to the microcontroller. If you want to have a look at my code, download it, it is attached.
  3. Have fun!
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so cool :D:D:D:D:D::D:D:D:D:D:D::D:D:D:D:D:::D:D:D:D::D::D:D

how to attach steering options in the boat using rf module?

thank u very nice so easy

How do I maintain the orientation of the motor?

For some reasons I couldn't open the MiniRobot.pde..

1 reply

Awesome idea. Very simple method for achieving something great!

what is the program for it to work?

Does it actually work?

hai dud I cannot find how to use the MiniRobot.pde

hai dud I cannot find how to use the MiniRobot.pde

hai dud I cannot find how to use the MiniRobot.pde

hai dud I cannot find how to use the MiniRobot.pde

hai dud I cannot find how to use the MiniRobot.pde

hi, are you aware that the props need to be at an angle to run and not straight.

nice idea though

i cant get it .

can you plz tell me how you instal sonar on motoruino.


2 replies to increase the speed of the robot?

is it depend on microcontroller ?

It depends on your motors and on the voltage you give them.