Electrical
From RoboWiki
The Electronics used in F.I.R.S.T. Robotics are based off of industry standard equipment. The compact Rio by National Instruments allows us to make numerous advanced ideas come true. With the number of sensors and inputs we can run very resourceful autonomous modes. To understand the equipment used by the electrical team may take quite some time. We have to organize, layout, and connect components using appropriate gauge wire, solder tiny chips, and pins. Research resistors and other components, and decipher schematics. All the while being sure to cooperate with the mechanical and programming teams. You have to be sure to not exceed what space has been allotted for electrical by the mechanical team, and still allow the programming team time to test their code with the equipment before you install it. Some of the custom work involves using components such as LEDs and Resistors. This custom work may likely, but not always, require soldering. There are all sorts of wires used in electrical work and you should be familiar with them if you're going to do electrical work.
General layout of an electronics system.
Power:
http://usfirst.org/uploadedFiles/2009%20Power%20distribution%20diargam.pdf
Contents |
NI Compact Rio
The Compact Rio from National Instruments is the main brain of the robot. It can read C++, Labview, or Java, and processes at a much better rate than the previous IFI computer. To send signals it relies on the "bumpers" placed at the top of it's modules, the analog, digital, and pneumatic bumpers. The digital bumper plugs into the Digital Sidecar, and relays signals through PWM cables from there.
Power Distribution Board
The Power Distribution Board uses Wago connectors, meaning much fewer crimps. There are 8, 40 amp slots, and 12, 30 or 20 amp slots. Special connectors on the end of the board are available for the Axis camera, Compact Rio, and Wireless Gaming Adaptor. It connects at the top to a 120 amp breaker, and from there connects to the battery with an Anderson connector.
Speed Controllers
There are 3 types of speed controllers available for use: the Victor 884, Luminary Micro Jaguar, and Texas Instruments Black Jaguar. The Victor has been around for a long time and is a rugged speed controller. It does it's job and rarely fails, only when a FET (field-effect transistor, the controller of output voltage for the motor) is blown will the Victor cease to work usually. Jaguars are much more complex and helpful though slightly less reliable. Jaguars have many output connectors for data including available CAN-busing (controller-area-network), among others. The voltage curve output for Jaguars is smoother, though it very slightly reduces overall power.
Spikes
Spikes are the relays for pneumatics. Using Spikes you can switch a solenoid valve on or off to do anything from raising a ramp or arm, to switching gears on an AndyMark Supershifter gearbox like on Jotunn. They also regulate power to the compressor but should be handled with care. Compressors love to eat up the small yellow 20 amp fuses Spikes typically use.(because they're one-time use) However to solve this problem it is recommended that you replace the small yellow fuse with an auto-resettable black 20 amp fuse. If it pops during the start-up of the compressor (when it typically occurs) it'll reset quickly, ensuring continued use. For solenoids no switching of fuses is necessary, the yellow 20's work perfectly fine. Spikes can also be used to control motors, but they only allow for full forward and full reverse, and are still limited to 20 amps of output.
Wireless Gaming Adapter
The Wireless Gaming Adapter is the communication device for the robot. Using 802.11n wireless it connects to the Driver station to receive all signals. You must be sure the Driver Station and Wireless Gaming Adapter are running on the same network. It is best to keep the adapter in an easily accessible place, preferably clear of obstructions. It uses a special connection at the base of the Power Distribution Board for power.
Axis Camera
Vision for the robot is provided by the Axis Camera. Coming with a small servo operated turret it scans the field and can see in colors, and with the help of the Compact Rio, discern colors like the green and pink posts in Lunacy. It also has a special connection at the base of the Power Distribution Board.
Classmate
The 2010 Driver Station. The robot is controlled through this small custom laptop computer, with controls being simply plugged in. Two simple USB joysticks can provide control along with a USB emergency-stop button. Obviously other custom components can be added either through the USB, or possibly other interfaces.
Discontinued Items
- IFI Computer
- IFI Driver Station
- Victor 883
- Maxi Fuse Block
- Black Fuse Block
- Power Distribution Blocks
- Radio
- Camera
- 2009 Driver Station
