This is the first year that we’ll actually be using the sensors given to us by FIRST and I’m wondering how one would go about wiring them. The accelerometer looks like I could just solder on the male end of a few PWM cables and be set, but I’m not too sure what to do with the gyro. I remember from previous years the gear tooth sensors required power from the main board to run and I’m not sure if that’s the case with these new sensors. We’ll also be using the two included optical encoders. I’m pretty sure I understand those, the A and B channel are signal lines with common ground and power. And all these are connected as analog inputs, right? Three channels for the accelerometer, one channel for the gyro, and two for each optical encoder.
EDIT:
I took another look at the sensor manual but that didn’t help very much.
2ND EDIT:
Also I would definitely take any suggestions for building a shaft to mate with the spindles of the optical encoders from the Kit of Parts. I see that they have small grooves so that would could probably machine an axle with ridges on it to fit the grooves.
You can use PWM cables and just solider them on. The encoder uses digital inputs not the analog. The Gyro and accelerometer use the analog inputs. Open the examples in Labview for each of these sensors and study them to test your sensors and knowledge.
The encoders attach directly to the machined end of the drive shaft on the Toughbox. You can buy mounts for them for $4 each at andymark.biz.
I’m still not clear on which pads go to which pins. I’m not sure if the +0V refers to signal or ground, I’m assuming the latter. Also the gyro has two sets of pads, does that mean it connects to two analog inputs?
We plan to mount two of the encoders on free wheels without gearboxes or motors, so I don’t think a ToughBox couple is what we’re looking for…
The gyro board has both a temperature sensor and a gyro. Gyros are sensitive to changes in temperature, so the temperature sensor can be used to reduce some of that error. Both should be connected to analog inputs.
My team are soldering a 3x1 female header to the boards rather than soldering the PWM directly. The advantage of this is that a PWM connector can now plug in directly to the board, so if we need to rewire it, it is a simple unplug.
We’re having trouble figuring out which of the 11 holes we should solder a PWM cable to. We can see the voltage and ground markings, but does this mean that we have to run power for each axis we want data from? Also, what are the two holes outside of the box for?
If anyone could post some pictures or a really good description, we would be very grateful.
You only need one ground and one power connection. There are 3 extra of each to give you the options to choose what wiring method is best for you. Unfortunately, that means that rookies may be overwhelmed with options.
If you only need one axis, use a 3 conductor cable (PWM cable) to connect to the appropriate column of pins.
If you need two axis, you may
use 2 3 conductor cables (do the first option twice)
use 1 3 conductor cable (the first option) plus a lonely wire that is connected only to the second axis
If you need all three axis, you may
use 3 3 conductor cables (do the first option each time)
use 1 3 conductor cable (the first option) plus two lonely wires that are connected only to the other axis
use a 5 conductor cable to pick up the top row
use a 3 conductor cable to pick up the three axis and a 2 conductor cable to do power and ground
This list isn’t exhaustive, if you can find something that works for you, go for it. Just remember not to reverse power and ground!
Okay, on my team, we understand the wiring on the gyro and the accelerometer, but we don’t get which one is the analog module… We SHOULD know this, but we cant figure out where to look…
