Title:Testing the Velocity of a Motorized Robotic Car at Certain Depths Underwater

Problem Statement: How fast will our robot be able to travel underwater over a distance of 10 feet?

Hypothesis: We believe that our robot car will move along the bottom of the pool of about half a foot every second. Here are some sample tables of our hypothesis.

  Feet Traveled Time in Seconds

Trial 1

10 20
Trial 2 10 20
Trial 3 10 20

Method and Materials

Building Robot:

First, we built a frame out of PVC pipe in the shape of a rectangle. Length13.5 inches, width 9 inches. We then glued 3-way PVC Ts onto those corners. We glued those together with PVC glue. Then, we glued the motors to the back with JB Weld type epoxy. Next, we sawed parts of the sides off, placed in some 3-way connectors, and then created an upside down V-shape of pipe coming out of the sides, more towards the back of the craft. Next, we took our switches, put them in balloons, soldered the ends to our motors and batery cases, then taped the to the top part of the V-shape of pipe. We then zip tied our batter casings, consisting of plastic toothpick holders sealed with silly putty, to the side of the V-Shape also. To fit the propellors onto the motors, we used some small plastic tubing attached to the shaft of the motor to make it slightly thicker, which enables the boat propellors we got to fit onto the motor shaft.

Robot Materials note: these are the required materials, you may want extra in case some of your materials break.

6.5 feet of PVC pipe (you will have some extra)

Two 3 volt motors, WATERPROOF

Extra 18 Gauge wire( around four to six feet, preferably different two colors)

Plastic toothpick holders

Silly Putty

Nine volt batteries w/ attachment

Switches w/ positive/negative wires coming out of both ends

Balloons, Large enough to fit the switches in

METHOD:
1. Place Robot care in water on bottom of pool
2. Measure distance that you want car to go over (ex 10 ft)
3. Get stopwatch ready
4. Flip switches connected to car and start stopwatch as soon as car starts
5. Stop stopwatch when car travels desired distance
6. Record time. repeat as necessary
MATERIALS: Includes extra tools if something goes wrong
Robot Car
Exacto Blade
Extra Wire Lengths
Soldering Iron
Extra Solder
Extra Zip Ties
Extra Motors
Tool Kit Includes:
Needle Nose Pliers
Wire Cutters
Screw Driver with Various heads
Tweezers
Glue Gun
Extra Glue Sticks
Extra Props
Water: 2
Air: 3
Plastic tubing for Props
Extra Balloons
Extra Batteries
Extra PVC Pipe
Hacksaw
Pliers
Tape
Normal
Electrical
Masking
Extension Cord
Extra Silly Putty( for sealing)
Extra Battery Casing
PVC Glue

Conclusion: Our robot moved at a speed of about .6 feet per second, taking about 16 seconds to travel 10 feet at a depth of 9 feet.