uranor
Dec 16, 2008, 06:37 PM
Hello,
being new to the world of IRUs, I was trying to clarify what is the exact meaning of some quantities found on gyro spec sheets. In particular, what does Rate Noise Density (deg/sec/sqrt(Hz)) means? Note that this is dimensionally equivalent to deg/sqrt(sec) which is usually called rate random walk..
Assuming the following simple Gyro model:
wg = w + b + v
d/dt (b) = u
v ~ N(0, sigma_v)
u ~ N(0, sigma_u)
where:
wg is the angular velocity measured by the gyros
w is the true angular velocity
b is the gyro bias (aka drift)
u, v are random white noise processes of standard deviation sigma_u and sigma_v respectively.
I understand that sigma_v is also called angular random walk, so how can I figure out what sigma_u is in a spec-sheet? Any help in deciphering the ADIS 16355 spec sheet would be appreciated.
Thanks!
being new to the world of IRUs, I was trying to clarify what is the exact meaning of some quantities found on gyro spec sheets. In particular, what does Rate Noise Density (deg/sec/sqrt(Hz)) means? Note that this is dimensionally equivalent to deg/sqrt(sec) which is usually called rate random walk..
Assuming the following simple Gyro model:
wg = w + b + v
d/dt (b) = u
v ~ N(0, sigma_v)
u ~ N(0, sigma_u)
where:
wg is the angular velocity measured by the gyros
w is the true angular velocity
b is the gyro bias (aka drift)
u, v are random white noise processes of standard deviation sigma_u and sigma_v respectively.
I understand that sigma_v is also called angular random walk, so how can I figure out what sigma_u is in a spec-sheet? Any help in deciphering the ADIS 16355 spec sheet would be appreciated.
Thanks!