Gyro Sensor is changing a degree every second or so

Hello All,

We have had the Vex IQ for a few days and having a blast with it but we have ran into a few errors.
I was wondering if my Vex IQ brain is bad, if someone else can try this and let me know if they have same issues that would be great. Thanks

  1. Program: RobotC 4 30 day free trail with Vex IQ update to 1.7
  2. Sample Program used: Gryro Display Values.c
  3. Problem on the Vex IQ the values will move a degree every second when the robot is sitting still
  4. I have 2 gryro sensor and this has happed to both.

I know on other platforms unless the sensor is perfectly still during the calibration/initialisation of the sensor you get this kind of behaviour. If your program doesn’t have it, try including a short wait at the beginning to give the sensor some time to get its bearing
vex 001.jpg
vex 002.jpg
vex 003.jpg

I updated every thing and made sure gyro was on a firm foundation and gave it a 60 second delay at the beginning and it still changes the degree and heading values by 1 every second.

I spoke with one of the ROBOTC developers about the calibration functionality in the gyro. I believe that it may be part of the next release. You can chose a number of different levels of calibration. The longest one takes 60 seconds and will result in a drift rate of 0.035 dpm. However, very reasonable results can be achieved with just a 4 second calibration cycle, which results in a 0.56.dpm drift rate.

When the gyro API was first created, this functionality had not been published or exposed and so was not implemented.

= Xander

I had this problem and may have been caused by a low battery as previously it was fine. Still trying to identify problem.

Any solutions to this issue? We have just purchased a brand new vex iq kit and a gyro sensor, we are using RobotC and the sensor just keeps decrementing. I see in RobotC there are some parameters for calibrating the gyro e.g. “gyroCalibrateSamples1024” but there is no documentation I can find or sample code I can find that can help me calibrate it. I tried lowering the sensitivity… all that does is slow down the rate at which the sensor decrements.

jpearman answered the question over here:
Thank you!