Page 121 - Rapid Learning in Robotics

Chapter 8

Application Examples in the

Robotics Domain

As pointed out before in the introduction, in the robotic domain the avail-
ability of sensorimotor transformations are a crucial issue. In particular,
the kinematic relations are of fundamental character. They usually describe
the relationship between joint, and actuator coordinates, and the position
in one, or several particular Cartesian reference frames.

Furthermore, the effort spent to obtain and adapt these mappings plays
an important role. Several thousand training steps, as required by many
former learning schemes, do impair the practical usage of learning meth-
ods in the domain of robotics. Here the wear-and-tear, but especially the
needed time to acquire the training data must be taken into account.

Here, the PSOM algorithm appears as a very suitable learning approach,
which requires only a small number of training data in order to achieve a
very high accuracy in continuous, smooth, and high-dimensional map-
pings.

8.1 Robot Finger Kinematics

In section 2.2 we described the TUM robot hand, which is built of several
identical finger modules. To employ this (or a similar dextrous) robot hand
for manipulation tasks requires to solve the forward and inverse kine-
matics problem for the hand finger. The TUM mechanical design allows
roughly the mobility of the human index finger. Here, a cardanic base joint

J. Walter “Rapid Learning in Robotics” 107