All images courtesy of Alex Slocum.
The picture below is a schematic overview of the whole system. Two batteries supply power to the control box. The control box distributes that power to the four actuators based on commands it receives from the transmitter. The transmitter receives commands from joysticks/throttles via the microprocessor. For the details of each sub-system, please consult the appropriate sub-section of this page.
Control box system schematic.
The above figures indicate how to wire both the Amp 14 pin connector (to connect to your motors) and the 4 pin connector (to connect to your batteries). Please obtain the pin and lead wire (PDF) spec from the fastener cabinet. Pay particular attention to how the batteries are wired! This wiring layout is not done arbitrarily - if the battery plug is wired incorrectly, either the control box will not turn on, or worse, the batteries will short within the plug, which will damage the control box and possibly cause your your batteries to explode!
Incorrectly wiring either plug will result in damage to your machine, batteries, and control box!
Motor connection photo.
All wiring must be insulated. This includes wire splices, soldered connections to the battery cradles, and connections to actuators. This is most easily done with electrical tape, though most securely done with heat shrink tubing. Poorly insulated connections are a confirmed source of controller problems.
The staff will not assist with machine debugging until all connections are properly insulated. Machines without properly insulated connections are barred from competition
Recommended: Download the Solidworks 2001 solid model of the control box: Control_Box.zip (ZIP - 2.0MB) (The ZIP file contains: 25 .sldprt files, 3 .sldasm files, and 1 .swj file.)
Contained within the zip file are two different versions of the solid model - one high quality version and one low quality. For almost all purposes of 2.007, the low quality version will suffice. It contains all the necessary dimensions while keeping the computer's required processor speed to a minimum. The high-quality version, however, serves as a useful example of some of the advanced features of Solidworks.
While we have striven to make all the boxes identical to each other and the solid model, some variation is inevitable, however, and it is the student's responsibility to account for it.
Control box image 1.
Control box image 2.
3 views on control box image.
Control box 2-button image.
PDF spec)Students will control their machines with four joysticks/throttles. The channel each joystick controls is indicated by color. If you like, you can think of pushing the throttle handle away from you as "forward," and pulling it towards you as "backward," with null point in between, but what "forward" and "backward" mean for a machine is governed by how the AMP plug is wired. See the wiring section for more information. Full forward corresponds to approximately 6.0V (voltage depends on loading and state of charge) across the motor terminals, and full backward corresponds to -6.0V across the motor terminals.
"High" and "Low" have no meaning. No functionality is associated with the buttons at this time.
Remember, driving 2.007 machines is difficult. Plenty of time should be allocated for practice.
Control podium image.
Transmitter box diagram.
If the joystick system is unavailable, machines may be driven from the Futaba transmitter directly. The figure above identifies the channels and directions. Please confirm the transmitter matches the control box.
The contest will use eight control boxes and two spares. Each table will have four control boxes. Those four control boxes will be set to only two different frequencies. Two control boxes will share each of the four frequencies. As in previous years, the tables will have color coded starting regions. One table will be blue and orange. The other will be red and yellow. Each color starting zone will be assigned a frequency. The table below summarizes this.
| TABLE ONE | TABLE TWO | ||
|---|---|---|---|
|
Blue "A" Blue "B" X1 Mhz. |
Orange "A" Orange "B" X2 Mhz. |
Red "A" Red "B" X3 Mhz. |
Yellow "A" Yellow B" X4 Mhz. |
To keep the contest going at a good clip, control boxes will be installed in the pit area. To prevent machines from running wild in the pit area, the boxes installed there (the "B" set for example), will be left off. Only when machines are placed on the table and about to start will their control boxes be turned on. After a contest, control boxes will be returned to the pit area to repeat the cycle.
From the Novak Reactor Reversible Manual:
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