From: Keith Packard Date: Sun, 9 Oct 2011 04:19:52 +0000 (-0600) Subject: altos: Improve TM v1.0 apogee estimate X-Git-Tag: 1.0.9.2~3 X-Git-Url: https://git.gag.com/?a=commitdiff_plain;h=ca036c5616c3e745c0b878ed90618d4ff710c0e5;hp=ca036c5616c3e745c0b878ed90618d4ff710c0e5;p=fw%2Faltos altos: Improve TM v1.0 apogee estimate v1.0 boards have noisy accelerometer data caused by interactions between RF transmission and the accelerometer measurements; this noise generates a negative bias in the accelerometer readings. The net effect is that the estimated speed is lower than the actual speed, causing early an apogee estimate. By increasing the sigma value for accelerometer data, the kalman filter 'trusts' the acceleration data less, putting more weight on the barometer data. This causes the estimated time of apogee to be closer to the correct value. This reduces the response to changes in acceleration. This new value is applied solely to TeleMetrum v1.0 boards. v1.1 boards correct for this error, and hence can use the correct sigma value for the accelerometer. Signed-off-by: Keith Packard ---