Got the Altitude sensor working (BMP085). This graph shows the responds from holding the autopilot near the roof then lowering it to the floor, then back again. All in all about 8 ft. A little noisy, but not too bad. I haven't attempted any filtering of the data yet.This graph shows the accelerometer data as I hand held it and did several rotations about the roll and pitch axis.This plot shows the noise floor of the IDG500 and LISY300AL. The LISY300 is a little quieter, but not by a whole lot. For the most part I'm happy with the performance of the IDG500. Check out the video of the Attitude Estimator if you haven't already.I also got the PWM inputs done for measuring the pulses from the RC Receiver. Here is a quick rundown of status.Power Supplies - workingProcessor - working12 bit AD - workingGyros - workingAccelerometers - workingAirspeed Sensor - workingUSB - workingAltitude Sensor - workingMagnetometer - workingGPS Interface - workingRF Interface - Not DoneCurrent Monitor - workingVoltage Monitor - workingSD Card - Not DoneServo Outputs - workingPWM In - workingI'll get the RF Interface running tomorrow and start sending messages to the ArduPilot ground station. After that I need to finish up on processing the magnetometer to give a heading for removing drift in the Yaw axis of the Attitude Estimator, then it's time to start looking for an airframe to install the autopilot in and begin the stabilization process.Regards,Brian
How does the attitude estimator work? Are you just sampling signals or is there some sort of state-estimation going on? I couldn't find an answer in your other posts.
If you post some data for us, I might be able to you help you out some. I've done some of this before, and I'm really curious to see how accurate this thing can get.
I think you could definitely clean the pressure data up a lot using a moving average filter, thanks for pointing out the BMP085 to me, looks like a good simple cheap sensor.
IDG500 is showing about .8 deg/sec RMS drift rate from what I see, hopefully some low pass filtering will help.
Mig King,
Yea, I still have four blank boards. I haven't had any takers yet. I'm going to build a second one up and start looking for an interested party who can contribute to testing and coding. Preferably someone with a background in controls to help get the loops implemented and tuned.
Comments
If you post some data for us, I might be able to you help you out some. I've done some of this before, and I'm really curious to see how accurate this thing can get.
IDG500 is showing about .8 deg/sec RMS drift rate from what I see, hopefully some low pass filtering will help.
Yea, I still have four blank boards. I haven't had any takers yet. I'm going to build a second one up and start looking for an interested party who can contribute to testing and coding. Preferably someone with a background in controls to help get the loops implemented and tuned.
Thanks for looking,
Brian
They hot re sized when I uploaded them. Not sure how to get around that so here they are as meta files so you can zoom in and scroll around.
accelerometer data.wmf
gyro data.wmf
pressure differential in room .wmf
Hope that helps,
Brian