Who Needs Emotions? The Brain Meets the Robot

architectural basis of affect 235
While this idea applies in principle to agents of all levels of complexity,
in practice there are limits to the approach, and the situation will already be
very different for more complex agents. For one, implementing the control
system as a finite-state controller will not work as the number of states of a
complex agent (e.g., with thousands of condition–action rules involving
complex representations) will likely be too large for the state table to fit into
a standard computer. Hence, the control system needs to be implemented
in a virtual machine that supports multiple finite-state machines with substates
and connections among them. In short, a complex architecture with
complex states will have to be implemented in a virtual machine that supports
the required complexity. While transitions are immediate in finite-state
machines, many physical steps may be required for a complex virtual machine
transition (like a computer updating a simulated neural net). Finitestate
machines do not need alarm systems to interrupt normal processing in
order to react to unforeseen events: they simply transit into a state where
they deal with the circumstance. Complex systems with multiple finite-state
machines with complex substates, however, need a way of coordinating state
transitions (especially if they have different lengths, might take different
amounts of time, or might even occur asynchronously). In that case, special
mechanisms need to be added to improve the reactivity of the system (i.e.,
the time it takes to respond to critical environmental changes).
Following this reasoning, one would expect to find something like alarm
mechanisms in complex agents that need to react quickly in real time to
unforeseen events. Such systems might lead to internal interactions instantiating
emotional states as defined above which the designers did not intend
(e.g., an operating system with a mechanism that terminates processes or
limits and reallocates resources in response to an overload might delete processes
urgently required for some subtask).
Returning to the question of whether robots need or should have emotions,
the answer will depend on the task and environment for which the robot
is intended. This niche, or set of requirements to be satisfied, will in turn determine
a range of architectures able to satisfy the requirements. The architectures
will then determine the sorts of emotions that are possible (or desirable)
for the robot. Here are some examples of questions designers may ask:
Will the robot be purely for entertainment?
Will it have a routine practical task, for example, on a factory
floor or in the home (cleaning carpets)?
Will it have to undertake dangerous tasks in a dynamic and
unpredictable environment (as in the Robocup Rescue project)?
Will it have to cooperate with other agents (robots and humans/
animals)?