Tom Foolery is a five-function animatronic figure. What makes each of Tom’s five functions move is a specific type of electrically powered motor called a Servo Motor. Tom has two types of servo motors; Dynamixel MX-106R Servo Motor and Ultra Motion A1 Servo Cylinder Motor. He has three of the Dynamixel MX-106R servo motors which have a rotational type of motion and control his mouth open close function, his head tilt function, and his torso twist function. Tom has two of the Ultra Motion A1 servo cylinder motors which produce a linear type of motion and actuate his torso forward bend function, and his scepter side to side function. The Dynamixel servos are located in the upper half of Tom’s body, while one of the Ultra Motion servos is located in the base of his chair and the other one is located at the base of his feet under his scepter. In order for both of Toms servo types to operate they need two things, power and a control signal. The Dynamixel servos operate on 12 Volts(V) Direct Current (DC) and can only consume at maximum 5 Ampere (Amp) each. The Ultra Motion servos operate on 36V DC and can only consume at maximum 5 Amp’s each. The Dynamixel servos receive their control signal via the serial communication standard RS-485. The Ultra Motion servos receive their control signal via a form of digital communication called Pulse Width Modulation (PWM).
The power and control signal for Toms servos come from several pieces of hardware located out of sight up on Tom’s balcony. To Toms left is a typical nineteen-inch audio visual rack containing multiple pieces of hardware including a surge protector/ battery backup for the equipment in that rack. A small power supply that provides the control voltage for Toms main power on/off relay, and the control voltage for a relay that can quickly disconnect power to Toms servos in the event of an emergency, a typical network switch for connecting all our ethernet cables, a wireless microphone receiver for the microphone used by the GKTW actor interacting with Tom (read more about on the Audio page, and four small boxes called Weigl Pro I/O’s which are what receive all the control data from our main show controller and convert it into the control signal protocols mentioned above and those control signals to Toms electrical panel where it gets distributed along with power to Toms five servos. To learn more about the Weigl Pro I/O’s and the way Tom is controlled visit the System page.
Located to Toms right just out of sight to guests is his electrical panel. In addition to the already mentioned things that are done in here, this is where the power supplies that provide power for each of Toms 5 servos are located. Because they require different voltages there is a separate power supplies for the Dynamixel servos and for the Ultra Motion servos. Providing power for these power supplies there is a main 120V AC power cord coming out of the electrical panel that has a standard 3 prong plug on it like you would find on any medium size appliance like a vacume cleaner, and this kust plugs into a standard 15Amp style wall outlet up on the balcony. Before that 120V AC power coming from the wall can reach the two servo power supplies it goes through a built in surge protector in the electrical panel as well as a main circuit breaker for the electrical panel that will trip if the electrical panel tries to draw more than 15Amps. After that main circuit breaker the 120V AC power is distributed to two lower rated circuit breakers, one for each of the servo power supplies. This is just like how in your home you have a main circuit breaker that is can handle all the power for your house without tripping, but then you have circuit breakers for individual rooms and appliances that will trip at a much lower amount of power. The circuit breaker that the Dynamixel servo power supply is on will trip at 5Amps and the circuit breaker for the Ulta Motion servo power supply will trip at 8Amps. From these 2 circuit breakers the 120V AC power goes into the two power supplies where they convert it into 12V DC for the Dynamixel servos and 36V DC for the Ultra Motion servos. But before the DC power coming from the two power supplies can reach the servos it must pass through several safety components. The first is the relay for the emergency stop function talked about above. As long as the main power button on the touch screen in the green room is on and the person operating Tom has not pushed the emergency stop button the power will pass right through this relay where it will be split from one positive and negative connection from each power supply into individual positive and negative connections for each servo. To keep everything safe before reaching Toms servos these individual power connections pass through circuit breakers just like how in your home the power coming from the street goes through circuit breakers before going out to your appliances, lights, and wall outlets. Each of the Dynamixel servos and each of the Ultra Motion servos are on individual circuit breakers that will trip if the servo tries to draw more than 5 Amps of power. After exiting the circuit breaker, the individual power wires for each servo are combined into two thick cables that carry all of the individual power wires and all of the individual data wires from the electrical panel out to Tom and his five Servos. Toms electrical panel also has eight LED indicator lights to easily tell someone what is and is not getting power so they can easily troubleshoot problems and to keep them safe if performing maitence. To see a detailed description of what each of the eight indicator lights means look at the Electrical In Depth page.