RigidBodyStateSE3

[dmronga]

This PR adds the data type RigidBodyStateSE3 which includes pose, twist, spatial acceleration and wrench in one structure, as well as some missing subtypes. The motivation behind this is to have a complete representation of the state of a rigid body for dynamic control applications. The necessity to have a new type for this has been discussed in PR #116.

Two words on the data type:

• We opted for the name RigidBodyStateSE3 (SE3 stands for Special Euclidean Group with dimension 3) because we would like to push for group theoretic data types. The advantage is that operations on these types are clearly defined (for example only multiplication between two SE3 elements makes sense). Also most of modern robotics is built on the mathematical foundations of group theory and differential geometry, see e.g. here as reference
• The type can be seen in analogy to base/JointState where we have position, speed, acceleration and effort (force/torque)

@shivesh1210

[doudou]

Looks good to me. Given that you were the one recently introducing Twist and Wrench, I'd even be OK with changing the type definitions (that's why we need official releases ... to have stricter rules on that)

@2maz ... ?

[doudou]

Looks good to me. Given that you were the one recently introducing Twist and Wrench, I'd even be OK with changing the type definitions (that's why we need official releases ... to have stricter rules on that)

@2maz ... ?

Sorry, disregard the second part of the message. Misread the github diff (it was showing only the latest changes ...)

[2maz]

@dmronga thanks for taking the effort