Mechatronic Tank

Mechatronic Tank

We would like to introduce Mechatron, our mechatronic tank. When we designed and built Mechatron we wanted him to be tough looking, industrial, and retro-futuristic, with lots of metal, rivets, and gears. He’s built entirely out of aluminum, brass, and steel, but inside, he’s chock-full of high tech electronics. See pictures and more text below. And be sure to watch the video to see Mechatron in action!

 

Mechatron includes special wheels with rollers slanted at 45 degree angles and driven by dedicated gearboxes, four powerful motors, and a software-controlled drive system that we wrote that operates each of the wheels independently. The result is that he can move in any direction at any time in any orientation. In other words, he can drive forward and backwards or turn like a normal vehicle, but he can also drive perpendicular to the direction he’s facing or at any desired angle. Weighing in at forty five pounds, he is by far our heaviest robot, but he is also our most agile, which makes him tremendous fun to drive.

Mechatron’s gun turret pans 360 degrees, includes 8 range-finding sonars for target detection, a laser, and a high-powered electric automatic weapon that shoots brass or plastic pellets. Ammunition is fed from the base of the robot up through one of the articulated metal tubes attached to the turret (the other tube contains wires). He can fire extremely rapidly while standing still or moving.

Strips of 52 programmable RGB LED lights have been mounted on Mechatron’s underside and within his turret. The turret LEDs indicate the robot’s current mode and whether the weapon system is armed. The LEDs on the underside change color depending on the direction of each of the individual wheels (Blue = Stopped. Green = Forward. Red = Backward), which helps to illuminate how Mechatron’s unique drive system works.

Mechatron is designed to function in a variety of different modes, including both user-controlled Radio Control and/or fully-autonomous. For the RC mode, we built our own controller which matches Mechatron in look-and-feel. The left joystick controls the pan and tilt of the gun turret and includes the firing button on top (which is armed using the missile switch). The right joystick controls the drive system. Forward and Backward motion (Y-axis) moves the robot forward or backward. Twisting the joystick turns the robot in the direction of twist (Z-axis). Moving the joystick left or right (X-axis) causes the robot to strafe left or right while maintaining his current orientation. Combined X-Y-Z joystick motions create unique and agile movements, such as strafing in circles. The robot can move in any direction, while panning and tilting its turret and firing all at the same time.

 

Technical Specifics:

  • Overall Design:   Beatty Robotics
  • Arduino Software: Beatty Robotics
  • Metal armor plates: Beatty Robotics
  • Main Microcontroller: Arduino Mega 2560
  • Microcontroller used for controlling LED lights: Arduino Nano
  • Light Controller Software: Beatty Robotics
  • Wheels: AndyMark (special thanks to Andy Baker, who was great to work with on these)
  • Drive Gears: Modulox (special thanks to Dan Richardson at iR3 Creative Engineering & Andy Baker at AndyMark)
  • Pan-Tilt gears and other parts: RobotZone (special thanks to ServoCity)
  • Pan-Tilt Servos: Hitec Digital
  • Sonars:  (12) Maxbotix MaxSonar Ultrasonic Sensors
  • Turret Sensor Head: Beatty Robotics
  • RGB LED strips:  Adafruit (Go Blinky Belt!)
  • MP3 Sound Board:  Sparkfun MP3 Trigger
  • Servo Controller: Pololu Maestro
  • Voltage Regulators: Pololu & Dimension Engineering
  • High-amp Relays: DFRobot
  • Motor Controllers: (2) Dimension Engineering Sabertooth 2×25
  • Motors: (4) CIM
  • Wireless Communication:  Xbee Radio with Sparkfun Xbee Explorer Regulated board
  • Joy Sticks: (2) 3-axis hall-effect joysticks from CH Products
  • Batteries: (1) 12v 3-cell Lithium-Polymer 20C
  • Aluminum, hardware, fasteners, wire, tools, and much else: McMaster-Carr
  • Wire, electronic components, IC boards, and much else: Sparkfun & RobotShop
Talking Robots!

Talking Robots!

We flipped on the power switch for our robot named Security. Then a low rumble erupted from somewhere in the room. The song Mr. Roboto began to play and the robot danced, moving back and forth, spinning and turning, playing its lights–all to the music. It was hilarious! We learned how to change the robot’s software so that I could control the pattern of the robot’s dance. I made the dance longer, more complicated, and even more fun than it was before!

A lot of our robots now talk, play sound effects, or play music, including Security, Roamer, and Mechatron. They have different ways of talking. Roamer uses a text-to-speech chip that my Uncle Chris helped solder into place, and the others use a tiny sound board that reads MP3 files from a micro-SD card. Most of the talking robots say “Roger, roger” because we want them to be a bit like the Battle Droids in Star Wars. It is so much fun to make them say things!

One of the mp3 sound boards we use in our robots