How to Build a Turtle Robot

The turtle robot is a hybrid remotely operated pet (ROP) capable of operating in both a terrestrial and aquatic environment. Equipped with both a manipulator and a charged coupled device (CCD) for color vision, the operator can "see" and manipulate objects in the path of the ROP. In the aquatic mode, the ROP is equipped with three electric thrusters providing vertical and horizontal motion, USBL location and sonar. Terrestrial operation is on wheels powered by the thruster motors to emulate the slow, sure motion of a turtle in a terrestrial environment.

Difficulty: Challenging

Instructions

Things You'll Need:

• Seabotix LBV150SE-5 (2)
• Seabotix crawler skid
• LBV150SE-5 control console
• Parallel two-jaw manipulator
• Tritech International "Gemini" sonar
• Marine epoxy resin and thinner
• Commercial mold release spray
• Scissors
• Fiberglass cloth
• Paper mache
• Paint brush
• Paint
• Wrench
• Bolts, 1/2 in. diameter, and nuts
• MIG welder
• Sheet metal
• Drill and bits

1. Fabricate the turtle shell and head by making an armature for the shell from paper mache. When the paper mache armature has set, spray the armature with commercial mold release spray, then cover the armature with a layer of fiberglass cloth, taping the cloth into place. Trim any excess cloth. Apply the epoxy to the first layer of fiberglass cloth with the paint brush, then press the fiberglass cloth into the resin. Lay 10 layers of fiberglass, laying a layer lengthwise, then a layer across, alternating direction with each layer. Allow to cure for 72 hours.

2. Attach the manipulator to the front of the LBV150SE-5 (2) frame and connect the manipulator (REF 4) to the LBV150SE-5 (2) electronic hub with the press and screw coaxial cable provided. Attach the Tritech sonar unit to the unit frame using the attachment points provided and connect the sonar umbilical to the electronic hub with the press and screw connector. Cut the sheet metal into tabs, 2 inches by 2 inches, and drill 1/2 inch holes in the center of each tab. Weld the tabs to the top of the frame of the LBV150SE-5 (2) with the MIG welder.

3. Attach the crawler skid (REF 3) to the LBV150SE-5 (2) frame underside. Connect the skid and LBV150SE-5 (2) with the coaxial cable from the skid using the press and screw connectors on the cable. Plug the control umbilical from the control console into the press and screw connector on the LBV150SE-5 (2).

4. Cut the tape with the scissors and remove the fiberglass turtle shell from the paper mache armature. Attach the fiberglass turtle shell and head to the tabs on the top of the frame of the LBV150SE-5 (2) using the wrench, nuts and bolts. Be sure that the turtle shell does not drag the ground at any point.

5. Connect the control console to the power source. Turn on the console. Test the ROP for operations in forward and reverse, test underwater thrusters, test the manipulator. If water operation is desired, direct the turtle into the water.

Tips & Warnings

• Exercise caution when using the ROP around swimmers.

References

• Seabotix LBV150SE-5 (2)
• Tritech Gemini Sonar
• Crawler

Resources

• ROV Manual: A User Guide to Observation-class Remotely Operated Vehicles

[BarbaraAlvarez]

on 10/10/2009 Will, you did mechanical engineers the world over proud! Mom of a mechanical engineering graduate/2Lt in Chem. Officer course @ Ft. Leonard Wood
(Barbara)

[vonjenkton]

on 10/9/2009 Thanks a bunch!

I finished by robot turtle last night. My wife and I named it "Donatello". It did take about a week but was well worth it.