The Land Shark

This instructable was created in fulfillment of the project requirement of the Makecourse at the University of South Florida (www.makecourse.com) The Land Shark is an Arduino controlled robot with all terrain capabilities and a trash retrieval mechanism that is able to pick up and stow small pieces of garbage such as cigarette butts and food wrappers. The project is requires a lot of patience and planning to complete, but is overall a fairly simple design. Have fun!

Step 1: Materials

For the Land Shark project you will need:

• 1 4X6', 1/4" thick plywood
• 2 10X1/2", 1/4" thick plywood
• wood glue
• 4 RC car wheels
• 4 DC motors
• 1 Arduino Uno
• 1 small breadboard
• 1 H-bridge motor driver
• 1 10" rack and pinion set
• 12" of fishing wire
• 2 180 degree servo motors
• 1 continuous servo motor
• hot glue and hot glue gun
• connector wires

Step 2: Set Up

Begin by using a box generating website such as MakerCase.com to design a box with 6X6X10" outer dimensions with 0.5" teeth on all edges. Save the design as a DXF file to be loaded to a laser cutting machine. Run the laser cutter for about 10 passes to cleanly cut through your plywood. On two of the 6X10" pieces, cut a 3X3" square into the wood, centered on the 6" length and about 3 inches down the 10" side. Also cut out the 1/2X10" and 1/2X2" pieces for the rack and pinion system. Cut out a 5.5X1.5" piece for the trash barrier and a 1.5X1.5" piece for the ramp shelf within the body of the Land Shark.

For the 3-D printed parts: Design a ramp similar to the one shown with a width of 2" and a hole to fit a standard 180 degree servo motor. Do not print the ramp with more than 10% infill to reduce the weight and improve servo performance. Design two sides of a claw similar to the one shown with a width of no more than 2 inches. If needed, design and print adapters to fit your wheels to the DC motors similar to the adapters shown.

Step 3: Assembly

Assemble all but the top panel of the body together using wood glue. Glue the ramp shelf to the front panel of the body about 0.5 inches from the side and 2 inches from the bottom panel. Use wood glue to assemble the claw housing and drill holes in each 10" piece to fit a bolt that can fit the holes of the claw connectors. Use a bolt to hold the claw in place between the two sides of the housing and use a nut or hot glue to fasten (Ensure that this set up will still fit through the 3X3" squares in the top and bottom of the body). Use the quick set epoxy to adhere the rack pieces to the back side of the claw housing and be sure not to let it run past the edges of the rack as this can cause the support to get blocked and not allow the pinion to move the rack. Use hot glue or a quick set epoxy to glue the rack support to the edge of the 3X3" square on the outer surface of the top panel. Use an extra piece of wood as needed to extend the support out into the square to reach and properly hold the rack.

Motors: Once the body is set, use hot glue or a quick setting epoxy to adhere the DC motors to the bottom of the body as shown. Adhere the pinion to the continuous servo using the circular adapter and the quick set epoxy then adhere the motor to the inner surface of the top panel so that it will mesh correctly with the rack and move the housing up and down properly. Adhere a servo motor to the ramp shelf such that the 0 position is facing along the width of the body and adhere the ramp part to the motor so that the side of the ramp is parallel with the width of the body. Finally, tie approximately 2 6 inch pieces of fishing wire to opposite ends of a 4 point connector that is attached to the final servo motor. Position the connector so that at 0 degrees the claw is completely closed, then at 180 degrees the claw opens. Use a rubber band connected to both sides of the claw to provide just enough tension to close the claw when the servo is in the 0 degree position.

Step 4: Wiring

Adhere the motor driver to the bottom of the body close to the back of the chassis. Use jumper wires to connect the wheel motors to the motor driver, then up through the chassis to the Arduino board. Also wire the servo attached to the claw mech