3 research outputs found
18th IEEE Workshop on Nonlinear Dynamics of Electronic Systems: Proceedings
Proceedings of the 18th IEEE Workshop on Nonlinear Dynamics of Electronic Systems, which took place in Dresden, Germany, 26 – 28 May 2010.:Welcome Address ........................ Page I
Table of Contents ........................ Page III
Symposium Committees .............. Page IV
Special Thanks ............................. Page V
Conference program (incl. page numbers of papers)
................... Page VI
Conference papers
Invited talks ................................ Page 1
Regular Papers ........................... Page 14
Wednesday, May 26th, 2010 ......... Page 15
Thursday, May 27th, 2010 .......... Page 110
Friday, May 28th, 2010 ............... Page 210
Author index ............................... Page XII
Towards reasoning and coordinating action in the mental space
Unlike a purely reactive system where the motor output is exclusively controlled by the actual sensory
input, a cognitive system must be capable of running mental processes which virtually simulate action
sequences aimed at achieving a goal. The mental process either attempts to find a feasible course of
action compatible with a number of constraints (Internal, Environmental, Task Specific etc) or selects
it from a repertoire of previously learned actions, according to the parameters of the task. If neither
reasoning process succeeds, a typical backup strategy is to look for a tool that might allow the operator
to match all the task constraints. This further necessitates having the capability to alter ones own
goal structures to generate sub-goals which must be successfully accomplished in order to achieve the
primary goal. In this paper, we introduce a forward/inverse motor control architecture (FMC/ IMC)
that relaxes an internal model of the overall kinematic chain to a virtual force field applied to the end
effector, in the intended direction of movement. This is analogous to the mechanism of coordinating the
motion of a wooden marionette by means of attached strings. The relaxation of the FMC/IMC pair
provides a general solution for mentally simulating an action of reaching a target position taking into
consideration a range of geometric constraints (range of motion in the joint space, internal and external
constraints in the workspace) as well as effort-related constraints (range of torque of the actuators, etc.).
In case, the forward simulation is successful, the movement is executed; otherwise the residual \u201cerror\u201d
or measure of inconsistency is taken as a starting point for breaking the action plan into a sequence
of sub actions. This process is achieved using a recurrent neural network (RNN) which coordinates
the overall reasoning process of framing and issuing goals to the forward inverse models, searching for
alternatives tools in solution space and formation of sub-goals based on past context knowledge and present inputs. The RNN+FMC/IMC system is able to successfully reason and coordinate a diverse range of reaching and grasping sequences with/without tools. Using a simple robotic platform (5 DOF Scorbot arm+Stereo vision) we present results of reasoning and coordination of arm/tool movements (real and mental simulation) specifically directed towards solving the classical 2-stick paradigm from animal reasoning at a non linguistic level