M c =kB.({dot over (b)} m ???{dot over (b)} i)=kB.({dot over (b)} m?????i ???{dot over (b)} m) where B is a standardized scalar representing the earth's magnetic field mean value, {dot over (b)}m is the unit vector aligned with {dot over (B)}m in the same direction, {dot over (b)}i is the unit vector aligned with {dot over (B)}i, in the same direction and ??i, is the desired angular velocity vecto