Forget about STEM! We’ve been all about STEAM (Science, Technology, Engineering, Arts, and Math) with our robotic zoo! Over the past six weeks, the kids at the North Tampa Robotics Club, South Tampa Robotics Club, and Learning Gate Community School have been hard at working building a robotic zoo to exhibit at the Tampa Bay Mini Maker Faire. This past week, 26 of us from these programs exhibited six different habitats featuring ten different student built robots. The effort took over 200 hours of effort to build the robots, program their behaviors, decorate them and build their habitats.

African Savanna

In this tropical grassland, massive herds of zebras and giraffes roam freely. Here, a couple of individuals pause briefly for our enjoyment.

The giraffe uses its long neck and towering body to reach the succulent leaves high up in the tree while the zebra, an animal rarely domesticated pauses momentarily and responds to being petted.

Materials
The habitat is constructed of paper mâché, painted and decorated with an assortment of craft and hobby materials. The animals use LEGO NXT Mindstorms for motion and sensing. The zebra’s coat was knitted by Mrs. Edwards.

Central American Jungle

Deep in the jungles of Central America, the plants attack and the animals do their best avoid predators by blending in with the background.

The Venus Fly Trap attracts insects and can sense the presence of a meal within its grasp. It feeds by closing on the helpless morsel trapping it and digesting it. Meanwhile, the chameleon’s unique ability to camouflage itself by changing colors to match its environment is simulated here by detecting colors in front of its sensor and then relaying the color data via XBee to an Arduino which has been programmed to gradually transition the skin to the newly detected color. An array of 15 RGB LEDs provide the lighting for the chameleon’s skin.

Materials
The habitat is constructed primarily of natural materials. The motion and sensors for both animals are LEGO NXT Robotics. In addition, the chameleon uses a third party NXTBee communications device and interfaces in real time with an Arduino using an Xbee shield. The LED array was built directly onto a plastic needlepoint canvas and wrapped around the torso. The head and tail are modeling dough.

The Jurassic Era

Witness the ferocious struggle for supremacy between these giant beasts as the T-Rex, stegosaurus, and crocodilian engage in a three way battle to dominate the Jurassic Period! Which will reign supreme? Each animal has its own special mode of attack.

Materials
The habitat is cloth over cardboard. Each animal is powered by a LEGO NXT robot with attacks programmed to occur at random intervals.

Dragon’s Realm

Prepare yourself to enter the realm of fantasy. Perched high atop a mist shrouded mountain, the dragon lays in wait for intruders. Venture to close and risk the wrath of this magnificent creature!

Materials
The mountain habitat was built using a five gallon paint can, crumpled newspaper and an old sheet to obtain the shape. The surface was then covered in paper mâché and painted with a black primer layer followed by a stone textured spray paint. Finally, the stone texture was dusted with more black to give the finish a bit of variety.

The dragon’s skeleton is constructed from LEGO TECHNIC elements and powered by LEGO NXT. The wings beat using synchronized cams that translate the motor rotation into an up and down motion. The dragon was originally finished with a hologram gift bag cut to size and LEGO Bionicle parts. The fire is simulated using a 12V fan connected directly to the NXT brain with a custom cable harness. The fan blows metallic streamers to represent flame.

The Minifig Garden

This minifig scale garden features a Hexbug maze. Can you see the word LEGO on the maze? Traversing this maze is a small collection of Hexbug Nanos. As they reach the end, a gantry robot detects the presence of the winner and transports it back to the start.

The audience was invited to add decorations to the garden from the available materials.

Materials
The entire garden is made of classic LEGO town elements with a smattering of castle and pirate bits for drama and interest.

The gantry robot is controlled by a LEGO NXT robot. Using the color sensor, it watches the capture tube for anything non-yellow to cross the sensor’s view. Once it sees the Hexbug, the capture tube is lifted and the robot traverses the gantry to deposit the bug back at the start of the maze. Three layers of specialized LEGO bricks provide a rigid track to span the 48 inch distance between the support columns and support the weight of the robot.

Prairie Dogs

This clever automaton is powered by a single LEGO NXT to drive both the hawk and the prairie dogs. The prairie dogs carefully scan their surroundings alert for predators who might threaten their colony. If a predator is sighted, they go into high alert to make the neighboring families aware of the looming threat.

Materials and construction techniques
The prairie is paper mâché over cardboard. The hawk’s perch is a five gallon paint can for a tree trunk covered with material and finished with a canopy of faux leaves.

The hawk’s skeleton is made from LEGO TECHNIC elements and its surface is finished with feathers. The wings are controlled by a single motor and synchronized using a pair of cams to beat in unison.

The prairie dogs are clay and sit upon a clever arrangement of cams and gears to achieve the complex motion. The cams are driven by a single NXT motor and are arranged to vary the speed and amount of movement for each prairie dog. You’ll notice that several of the dogs rotate as they emerge from their burrows. The rotation is accomplished using a combination of rack and bevel gears to create a complex motion from the motor’s rotation. The alert is triggered by an ultrasonic sensor mounted in the hawk (they look like eyes).

Tramway

Ride our electric tram as it winds its way through the zoo. This motorized train is in its third iteration in just two short months! At each end of the track, a switch reverses the current and sends the train back towards the far side of the exhibit.

Materials
The tramway is constructed exclusively with LEGO using vintage 9V battery boxes and motors.