Proto Quaternion definition

[YoshuaNava]

Hej,
In the protobuf definition of Quaternion, it is not very clear to which quaternion dimension each field corresponds, e.g:

Is it the case that

u1 = x
u2 = y
u3 = z
u4 = w

Or

u1 = w
u2 = x
u3 = y
u4 = z

for a quaternion defined as w + x i + y j + z k ?

Thank you.

[jontje]

Hej!

It is the second one:

u1 = w 
u2 = x
u3 = y
u4 = z

It follows the same definition as the RAPID data type orient

[gavanderhoorn]

@jontje: would this be something to add as a comment in the .proto file?

[jontje]

Definitely, I will do that

[gavanderhoorn]

@jontje: not sure, but I believe this one can be closed looking at:

abb_libegm/proto/egm_wrapper.proto

Line 126 in a278b7b

// Note: Lower priority than Euler angles. The quaternion is defined as: u0 + u1*i + u2*j + u3*k.

[jontje]

@gavanderhoorn: Yes, it can be closed, thanks for the reminder! 👍