Figured I'd clear up a couple of responses in this thread.
Quote:
Originally Posted by seg9585
Gyros are very sensitive to electromagnetic fields, this may be a problem so close to the roboRio.
Even if it wasn't, the chip I tried in particular is a single-axis gyro and will require more precise mounting on the robot. Many teams like to mount cRios/roboRios vertically or in a way convenient for troubleshooting or maintanence. Maybe an embedded 3-axis gyro would solve that problem, like the rRio's 3-axis accelerometer.
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Incorrect. MEMS devices are manufactured using non-ferrous materials, thus making them immune to strong magnetic fields. A single axis gyro simplifies the mounting on the robot. You only have one axis to worry about! The ADXRS450/453 are "rate gyros" which mean that they are designed to only report back...rate... in one axis!
Quote:
Originally Posted by Bryce2471
Sorry I'm a little late to the party on this thread. As far as this gyro goes (ADXRS453), it looks like there are two packaging options (ADXRS453BEYZ and ADXRS453BRGZ), I'm wondering which one you would recommend, and how you interface with it.
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You probably want the ASXRS453BRGZ version since the sensor will be easier to solder onto a PCB and the measured axis is located through the center of the part. You would solder the sensor down to the PCB just like any other IC. I would recommend purchasing the breakout board, though!
The 450/453 differ from the gyros used on the AndyMark breakout board in that the Analog to Digital conversion is performed within the sensor. This makes them much less susceptible to EMI. In an ideal setting, you would want the accelerometer attached to a rigid portion of your robot, and the gyro would be located as close to the center as possible.
Although the 6-axis and 9-axis sensors are cool, they are not designed for precision navigation applications. Noise levels on those sensors are orders of magnitude greater than what's available on application-specific sensors. I would strongly suggest that teams invest some time looking into the 450/453 if they want to have a solid drive system.
Another caveat of systems such as the nav6 is that they are not calibrated. Each sensor is unique and will provide a slightly different response when used in different applications. In that case, an integrated IMU such as ADI's
iSensor product line would be ideal.