Franka Emika Panda - FCI Package for Researchers; Robot Features Explained

Franka Emika GmbH © October 2018
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The FCI package - the bonus
for researchers
The Panda research package allows for real-me, bidireconal connecon
between a workstaon PC and the Arm. Also commanding the Hand is possible.
This interface (FCI) enables the user to implement specially created controllers
and applicaons with the robot. The package consists of libfranka, a C++ program
library, and franka_ros, an ROS interface with ROS Control and MoveIt integra-
on, which can be accessed at hps://www.github.com/frankaemika/. Detailed
informaon can be found in the corresponding API descripons and quick start
guides.
Some features
Joint space
Cartesian space
Redundancy
A joint space is the descripon of a robot pose using the rotaon angles of
the robot’s individual joints. In contrast to most industrial robots, which have
6 joints, our Arm has 7. This allows for an extremely high exibility. A certain
pose can be uniquely idened with 7 values in units of degrees. Movements
in the joint space move all joints simultaneously from the current posion to a
dened target joint pose. Here it is important to noce that the movement of
the end eector results from the rotaon of the joints and does not follow a
specic path (e.g. a line).
The Cartesian space allows an alternave descripon of the robot pose. Here, the
posion and orientaon of the end eector are the main focus. The representa-
on of Cartesian poses in three-dimensional space usually consists of three
values (in meters) for determining the posion and three values (in degrees) for
orientang the end eector. For a robot with 7 joints this representaon is not
complete for dening a certain robot pose. For more informaon, see the secon
“Redundancy”.
Movements in Cartesian space allow the exact tracking of predened paths in
space, such as straight lines. The changing of posion is called translaon, while
the changing of orientaon is called rotaon. The Cartesian movement of a robot
always depends on the reference coordinate system, which can be congured for
Panda via the conguraon of the end eector in the admin secon of Desk.
The Arm can reach a certain Cartesian pose with various joint conguraons.
This capability is called redundancy. In Panda this addional moon capability
is oen called elbow, because it matches the moon capability of the elbow in
a human arm. The redundancy of the Arm allows for a greater exibility when
teaching or execung Tasks. For example, it can be used to circumnavigate an
obstacle in order to grip an object located behind it. The behavior of the elbow
can be changed and adapted to each situaon. It can be set to freely movable or
immovable.
THIS IS PANDA