The BEST Return Kit with Gizmo
The BEST Returnable Kit contains a Control System and various peripherals used in constructing and controlling a BEST robot. The legacy control system has been based on the VEX Cortex microcontroller. The future control system (2024+) will move to an open-source design, called Gizmo, built around the Raspberry PI PICO microcontroller module. The Gizmo control system for a BEST robot consists of a few main components.
- Gizmo board (that resides on the robot)
- Joystick/Controller
- Driver Station
- A Field Management System
There are other components that support the system operation such as batteries, chargers, cables, etc.
When a participating team receives their Return Kit for use during the BEST Robotics competition, they will receive the following Gizmo components.
Gizmo Components in the BEST Return Kit
This is only a portion of the full Returnables Kit-
Gizmo Board with Power Cable & Switch
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7.2V Robot Battery
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Logitech F310 Joystick/Controller
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Driver Station
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Driver Station Battery
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Tether Cable
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USB Cable (USB A to B-micro)
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7.2V Battery Charger
Gizmo & Power Switch
7.2V Robot Battery
Driver Station & Battery
Joystick/Controller
Tether Cable
7.2v Battery Charger & Adapter
USB A to B-micro cable
The Gizmo Board
The Gizmo board is the main brain for the robot. When we use the word “Gizmo” stand-alone it is typicially referring to this board alone. The Gizmo is enclosed in a hard plastic case and provides interface ports for all the peripherals that might be needed on the robot. This includes 4 motor ports, 4 servo ports, 8 digital input/output ports, 3 analog input ports, 1 neopixel port, and 2 serial UART/I2C ports.
The board has an 8″ battery cable with power switch already attached. The 7.2v robot battery connects directly into the red/black powerpole connector. There is typically no need to unscrew the battery cable from the Gizmo board. The positive side (red wire) of the battery cable is always attached to the top screw terminal on the Gizmo, labeled with a + sign.
The 7.2 volt NiMh robot battery is the only battery that should be used with the Gizmo. The battery has been modified to include the red/black powerpole connector for increased reliability and lifespan.
Built-In Protection
The Gizmo does have reverse polarity protection for the battery attached to the screw terminals. Should the battery be connected opposite from how it is intended (e.g., the battery wires are swapped), the Gizmo will simply not function.
Notice that the motor ports are split into 2 banks of 2 ports. Each of these banks can support up to 8 amps of current before tripping the internal polyfuse and shutting down the port for approximately 2 minutes. When connecting motors, try to balance the load between the two motor banks. If you have 2 large motors, for example, connect them to different banks.
Joystick/Controller
A Logitech F310 wired joystick/controller is included with the Gizmo. This is the only controller that is guaranteed to work with. It has a typical game controller layout with two analog joysticks and 12 digital buttons.
- 4 buttons on the right (A, B, X, Y)
- 4 button D-pad on the left (up, down, left, right)
- 2 shoulder buttons on the front face (left, right top buttons)
- 2 trigger buttons on the front face (left, right lower buttons)
Each analog joystick also serves as a digital button by pushing down on the stick itself. Two other digital buttons include the START and BACK buttons. That’s a total of 16 programmable digital buttons on the controller. Digital buttons return a 1 or 0 value (pressed or not pressed).
The right and left joysticks are analog devices and send a range of values (0-255) for movement up-down and for movement right-left.
There is a switch on the back of the F310 controller that MUST always be in the “D” position (pushed to the right). If the switch is in the “X” position, the Gizmo will not receive data from the controller.
The controller is connected to the Driver Station through its USB cable. It should remain connected to the Driver Station when in use.
Driver Station, Battery and Tether Cable
The Driver Station is the device that provides the wireless or wired connection between the Joystick/controller and the Gizmo. It has an external battery that must be connected for it to function. The Driver Station battery is a USB power bank with a minimum 6000 maHr capacity. This capacity should allow the Driver Station to operate all day on a fully charged battery.
The Logitech F310 joystick/controller plugs directly into the Driver Station at the USB A port.
The Driver Station will communicate data from the joystick/controller to the Gizmo through a 2.4Ghz wireless connection.
When the tether cable is used, it provides a direct connection between the Driver Station and the Gizmo on the robot, bypassing the wireless operation. The tether cable plugs into the ETHERNET connector on the Driver Station and the TETHER (RJ45) connector on the Gizmo.
USB A to B-micro cable
The USB cable is used for uploading user programs to the Gizmo. The A style connector plugs into a computer and the smaller B-micro connector (D-shaped) plugs into the Student Processor USB port on the Gizmo. Refer to other lessons on programming the Gizmo for details on uploading programs.
