Homework 2 - Hybrid Deliberative/Reactive Robotics Paradigm

Due Monday, February 23, 2009

NOTE: This assignment, like others in this class, is due at the beginning of the class period. This means that if you are even a minute late, you lose 20%. If you are worried about potentially being late, turn in your homework ahead of time. Do this by submitting them to me during office hours or by sliding it under my office door. Do not send assignments to me through email or leave them in my departmental mail box.

Consider the following quote from Thrun in the assigned reading (S. Thrun. "To Know or Not to Know: On the Utility of Models in Mobile Robotics." AI Magazine, 18 (1): 47--54, 1997):

A key advantage to maps is that they enable robots to plan. For a task as simple as the one in the competition, however, deliberative planning was not even necessary because the exploration pattern could be predetermined entirely (p. 51).

Also consider that, besides planning, maps (or world models or other knowledge representations) can be used in a deliberative/reactive robot as inputs to behaviors. In this way, maps can be seen as providing virtual sensors for the behaviors. This is shown in Figure 7.2 (p. 261) in the Murphy textbook and described in Section 7.6.1 (p. 280) of that textbook.

The assignment.

Thrun’s claim that Jeeves (Thrun’s robot in the paper) did not plan deliberatively is true with regard to systematic exploration. However, Jeeves did use the map for planning other activities or subtasks (parts of the overall task of "cleaning up the tennis court"). List and explain two different activities in which Jeeves engaged in planning and explain why Jeeves was more efficient using planning than it would have been without planning.

Besides planning, Jeeves map was, in fact, used to provide virtual sensor inputs. List and explain two different activities for which Jeeves used its map to provide virtual sensor inputs and explain why Jeeves was more efficient using virtual sensor inputs in addition to actual sensor inputs than it would have been using actual sensor inputs alone.

What to turn in.

Turn in a typed copy of your work for this assignment. In total, your homework should run from 1.5 to 2 pages in length (roughly 80 characters per line, 50 lines per page). This does not count any figures that you may choose to include, which may be of any size.