Gimbal Lock & Raidial Velocity

[Bryan Higgins]

I came across these two subjects when trying to understand the dimensional
properties of a Control Line Plane in flight on Planet Earth.

Of course there has to be a Navigator in the center.

I belive building the "perfect wing" involves a deep understanding of science
as well as engineering skills. This hobby is really beginning to fascinate me.
Building and flying control line planes is actually really interesting, it can go
far beyond just flying in circles as some people presume.  Bryan H.

[phil c]

Interesting stuff.  My body goes into gimbal lock trying to do a wingover.  I can only bend so far in any direction!

[Neville Legg]

I get vertigo in a wingover!  I too have problems following the model due to arthritis in the neck! hate getting old

Cheers        Neville

[Peter Nevai]

Hey, Don't make fun of gimbal lock, Typically it occurs when the X axis an Z axis gimbal angle delta appoaches or equals zero. At that point, attitude correction beomes impossible because the contoller input as far as the gyro is concerned is only effecting rotation about the Y axis. But of course, in CL we only have rotation about the Y axis, gimbal lock does not apply as the state it represents is the normal mode of operation. I don't believe I know this, but once you have experienced gimbal lock first hand you can never forget it.

[Tim Wescott]

Hey, Don't make fun of gimbal lock, Typically it occurs when the X axis an Z axis gimbal angle delta appoaches or equals zero. At that point, attitude correction beomes impossible because the contoller input as far as the gyro is concerned is only effecting rotation about the Y axis. But of course, in CL we only have rotation about the Y axis, gimbal lock does not apply as the state it represents is the normal mode of operation. I don't believe I know this, but once you have experienced gimbal lock first hand you can never forget it.

I'm not sure how you're defining your axes, Peter, but you brush up against gimbal lock whenever you do a wingover.  If you wanted to keep your chest pointed along the direction of flight, then in theory you'd have to spin infinitely fast at the top of the wingover.

Of course, that's not really gimbal lock, and (unless your arthritis is really bad) your body provides enough axes of rotation that you can get by without the infinitely fast spin.

[Peter Nevai]

I'm not sure how you're defining your axes, Peter, but you brush up against gimbal lock whenever you do a wingover.  If you wanted to keep your chest pointed along the direction of flight, then in theory you'd have to spin infinitely fast at the top of the wingover.

Of course, that's not really gimbal lock, and (unless your arthritis is really bad) your body provides enough axes of rotation that you can get by without the infinitely fast spin.

+ - Y vertical,  +- X horizontal, +- Z fore and aft. Based on Gyro Compass, three axis control systems. When any two axis on the gimbal come into alignment, the gyro can lock because the spin on the two become aligned. Once that happens it is next to impossible to diverge the two. Think of two nested wheels spinning 90 degrees apart. Everything is fine one wheel stabilizes on one plane, say vertical, the other on the horizontal. Now create a sitwation where both wheels end up spinning on the same plane. They end up locking in place reinforcing the gyroscopic effect of each other resisting any motion shift on allbut one axis. Hence gimbal lock.

[EddyR]

Everone knows the best wingovers are done when we do then 180 degrees to the rotation of the earth,right??
Ed