Gyros and Accelerometers

[excel2474]

I've never used a gyro or an accelerometer. I was looking at the ones that came in the kop and I was wondering what you use to wire it to the cRIO. Do I just modify a pwm cable and if so, how do I connect it to the gyro? thanks

[kevin.li.rit]

Originally Posted by excel2474

I've never used a gyro or an accelerometer. I was looking at the ones that came in the kop and I was wondering what you use to wire it to the cRIO. Do I just modify a pwm cable and if so, how do I connect it to the gyro? thanks

You can modify a PWM cable and connect it to the analog sidecar. There are two outputs on the gyro, one is temperature and one is the turn rate. Red is 5v, white/yellow is signal and black is ground.

[excel2474]

Originally Posted by Coffeeism

You can modify a PWM cable and connect it to the analog sidecar. There are two outputs on the gyro, one is temperature and one is the turn rate. Red is 5v, white/yellow is signal and black is ground.

Ok, that's kind of what I thought, but I'm not sure how to connect the wires to the gyro. Is there some type of technique?

[EricVanWyk]

I was going to link you to the sensor manual ( http://usfirst.org/uploadedFiles/200...r%20Manual.pdf ), but that link isn't working for me at the moment. Perhaps it is because everyone is downloading everything, hopefully it will work soon. [EDIT] Actually, it was because my computer loves installing language packs and not telling me.

Both boards have the "standard" 3xN pin interface: .1" space, Signal 5V Ground.

The Accelerometer has an extra power and ground pin in line with the signal pins to allow teams to use a 5x1 connector.

Easiest method is to solder the male end of a PWM cable in for each signal, with white being signal. Female end goes into the analog breakout.

Alternatively, solder a female connector in and then insert the cable into that. We had feedback that some teams didn't like this method, so we didn't force it.

[Racer26]

Originally Posted by excel2474

Ok, that's kind of what I thought, but I'm not sure how to connect the wires to the gyro. Is there some type of technique?

<unsure if i'm stating the obvious>
The "technique" to which you would be referring is Soldering, http://en.wikipedia.org/wiki/Soldering
</unsure>

I personally like the suggested method of soldering the male end of a pwm wire right to the board.

Alternately, you could just solder some wire to the boards, preferably with a strain relief and then connect it to the analog breakout board with a pwm connector.

[pogenwurst]

Originally Posted by EricVanWyk

Alternatively, solder a female connector in and then insert the cable into that. We had feedback that some teams didn't like this method, so we didn't force it.

I'm a bit curious to know what teams didn't like about this method, as it's the one we're considering, but we've never done it before.

[Sparks333]

Originally Posted by pogenwurst

I'm a bit curious to know what teams didn't like about this method, as it's the one we're considering, but we've never done it before.

The short story is that since both the gyro and the accelerometer outputs an analog voltage, any connection made is extremely susceptible to electromagnetic interference, especially if the sensor is placed near a motor or solenoid. Additional connectors mean more points of weakness for the signal to deteriorate. A direct soldered connection is a more robust way to connect a wire to a pad than through an additional connector.

On a side note, if the interference gets too bad, you can always shield and ground the cable - doing that on an especially bad signal line can clean things up a little.

Sparks

[pogenwurst]

Originally Posted by Sparks333

The short story is that since both the gyro and the accelerometer outputs an analog voltage, any connection made is extremely susceptible to electromagnetic interference, especially if the sensor is placed near a motor or solenoid. Additional connectors mean more points of weakness for the signal to deteriorate. A direct soldered connection is a more robust way to connect a wire to a pad than through an additional connector.

On a side note, if the interference gets too bad, you can always shield and ground the cable - doing that on an especially bad signal line can clean things up a little.

Sparks

Oh! That clears things up nicely, thank you.

[Daniel_H]

So, all of you received an accelerometer at the KoP?

We didn't get one, they said to my coleague who went to NY go get our KoP they were short on accelerometers this year..
and I was so eager to use it.

[CDH Jeff]

our team didn't get either the accelerometer or gyro last year, and now we don't know how to wire, even with the help from this forum and the link. which holes are the xyz out? on the 3x3 grid on the accelerometer is it the unlabled row, or the one labereld OV? thats pretty much my only question, thanks for that link to the manual eric.

[comphappy]

Originally Posted by CDH Jeff

our team didn't get either the accelerometer or gyro last year, and now we don't know how to wire, even with the help from this forum and the link. which holes are the xyz out? on the 3x3 grid on the accelerometer is it the unlabled row, or the one labereld OV? thats pretty much my only question, thanks for that link to the manual eric.

moving from the xyz to the edge of the board it its:
signal
5v
ground (0v)