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Questions about the Hightechnic Gyro Sensor 
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Joined: Mon Jan 14, 2013 2:50 pm
Posts: 12
Post Questions about the Hightechnic Gyro Sensor
I have some questions. Does the gyro measure stuff by degrees? Why is there an offset needed? If I do
const tSensors GyroSensor = (tSensors) S2; //gyro sensor//

#define offset 598 //offset value may vary depending on sensor & temperature
long Gyro_value;

int cool = 40;

task main()
{
while(1==1){

Gyro_value=SensorValue(GyroSensor); //read the gyro sensor

The program doesn't work without the offset. What is the programming to calibrate the offset at the begginning of a program?
Thanks


Sun Jan 20, 2013 4:11 pm
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Location: Rotterdam, The Netherlands
Post Re: Questions about the Hightechnic Gyro Sensor
The offset is dependent on many things like temperature. The offset is different for each sensor, as it's an analogue sensor. My one tends to have an offset of around 619-625 or so, depending on planetary alignment.
The offset is best calculated as average of numerous measurements. You may want to take a look at my driver suite, specifically the hitechnic-gyro* files. Unless you're using a Sensor MUX, it is safe to ignore the SMUX files. You can download the suite from the link in my signature. The driver has a function that allows you to calibrate the gyro. Note that you should do this every time you start the program and that your robot should be perfectly stationary while you do this.

I would also advise you to upgrade to ROBOTC 3.55 B2, as there are bugs in 3.54 that affect things like casting from ubyte to int, which in turn affects my driver suite. You can find ROBOTC 3.54 B2 here: viewtopic.php?f=52&t=5122

= Xander

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Sun Jan 20, 2013 4:46 pm
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Joined: Mon Jan 14, 2013 2:50 pm
Posts: 12
Post Re: Questions about the Hightechnic Gyro Sensor
OK, I got the newest firmware and downloaded the newest drivers. I looked the gyro sensor part in the driver suite tutorial and it was kind of comfusing. Xander, please look at this other forum thread viewtopic.php?f=1&t=5362 and try to help.


Sun Jan 20, 2013 8:40 pm
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