[Rock-dev] Change in Eigen 3.2 which breaks the base types (and maybe other packages like orientation estimator)

[Matthias Goldhoorn]

On 25.11.2013 11:19, Sylvain Joyeux wrote:
> On 11/23/2013 05:07 PM, Javier Hidalgo Carrió wrote:
>> I did not fully get the point. What is the problem of using
>> toEulerAngles(a0, a1, a2) from Eigen?
>> The new euler helper (base::getEuler) only computes the euler angles in
>> ZYX in this order.
>> There are multiple conventions for proper Euler angles.
> Yes, and in most cases they are equivalent. We decided, once upon a time
> to "freeze" one as the default representation so that people that "just"
> want angles don't have to pick one.
>

@Alex: i think you are right, the result will ( and is already) 
yaw[2]:(-pi,pi), pitch[1]:(-pi,pi), roll[0]:(-pi/2,pi/2).
@Javier: for simplification i only choose the one we are decided in rock 
for decomposition.

@Alex (regarding gimbal lock)
The current implementation is equivalent to the old eigen 
implementation. To be sure i don't do something else there. I would 
simply recover the old behavior. If you know a better solution feel free 
to add this. But nevertheless i don't know how the gimbal-lock problem 
yould appear for a quaternion->euler, if you have a counter example feel 
free to add it to the test suite and maybe improve the current 
implementation. If we could go back to the eigen implementation i would 
agree, but i don't like to "check if a axis is ontop and turn 
every-other one", then we could really do the calculation by our own...


P.S. @Javier, please do not git pull if the remote i's newer, there are 
uneeded merges in base/types...

-- 
  Dipl.-Inf. Matthias Goldhoorn
  Space and Underwater Robotic

  Universität Bremen
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