[Up- imhofaq] [Map] [Prior: software] [Robot Wisdom home page]

Vision, robotics, planning, simulation and artificial life

NEW (March 2000): robotics links

Some miscellaneous related topics:

Human vision must work, in part, via the imagination - the mind projecting multiple possible images of the future (or the present). At any moment, each section of the visual field must be accounted for, to some degree, in terms of an imaginary projected image, not at all unlike a hallucination. (Learning about the world means fine-tuning our hallucinations!)

There's a cute book called "Vehicles: experiments in synthetic psychology" by Valentino Braitenberg (MIT Press, 1984), that shows how very simple electronic 'nervous systems' can allow very simple robots to exhibit fairly interesting behaviors, like approach and avoidance. This sort of emergent behavior is the ultimate goal of alife research.

There's a common fallacy that 'virtual worlds' could be built entirely out of the basic laws of physics - a Grand Unified Theory of Everything - so that the path of each particle in the world would be traced independently, by some super-super-supercomputer doing millions of math calculations each nanosecond. But this isn't even practical for a billiards simulator! What's needed, instead, is an inventory of 'particle stories' (cf Feynmann diagrams?) which are qualitatively distinct, which is likely how the brain itself does most of its physics predictions. There's a famous AI paper called "The Naive Physics Manifesto" (1978, Patrick Hayes) that broke early ground here.

Computer planning is in a very primitive state. The normal models require that the computer do a thorough search of a large number of combinations of plan-steps, looking for the most efficient one. This might be compared to searching a large rectangular field, one row at a time. An alternative model might be compared to a widening spiral pattern, where the first circular pass returns some extremely coarse proposal, and successive passes refine it further and further. The advantage here is that in real life one may not have enough time to complete the thorough search, so the 'spiral' model allows one to abandon the search at any point without ending up empty-handed. This spiral approach once again requires prioritising the elements of the planning domain.

Computer gaming is the only domain of commercial software in which programs are routinely evaluated for the quality of their AI - which in this case normally refers to the program's ability to serve as an intelligent opponent, even to stand in for a second human gameplayer. This sort of AI can be implemented as a set of possible story-cases to be executed under certain conditions.

Here's a breakdown of the current status of computers at various human games, compiled by Victor Allis (victor@cs.vu.nl):

Othello:
Strongest program (Logistello by Michael Buro) stronger than strongest human players.
Checkers:
Strongest program (Chinook by Jonathan Schaeffer et al.) has now defeated the world champion
Backgammon:
Strongest program (TD-gammon by Gerald Tesauro) at world champion level.
Chess:
Strongest program (Deep Thought II, by Feng Hsu and Murray Campbell) at about the 100th-150th place on world ranking
Bridge:
Strongest programs (unclear which) at amateur level
Go:
Strongest programs (several, see rec.games.go) at about 8-10 kyu, which is a little above novice level.

There's also a whole category of computer games devoted to simulations (although flight simulators, whose AI is comparatively trivial, consistently lead the field in sales). Maxis has done very well with SimCity, SimEarth, SimAnt, SimLife, SimFarm, SimHealth, and A-Train. "Civilization" is something like SimCity with inter-city wars. Games based on economic simulations go back as far as Lemonade Stand and the like.

Chris Crawford is the grandfather of social simulations, with Balance of Power, Balance of the Planet, and Trust & Betrayal. The first of these involves the realization that international politics is almost entirely a question of maintaining face (the esteem motive). The second, Balance of Power, shows how the interconnectedness of ecological factors makes simple solutions radically ineffective. The third is a very primitive first try at simulating a community of humanoid alliances. AI-history collectors will want to get the source code for T&B from Chris for $150:

Other interesting sims:

Hidden Agenda:
you're president of a Central American country-in-crisis, and must weigh the requests of various factions, with the help of your fallible advisors.
Shadow President:
ditto for US politics?

There's a very thorough article about computer game design here.

A nice game-ai page

Carnegie Mellon has an artificial-personality/ virtual-world project called "Oz" led by Joseph Bates.


Resources

comp.robotics newsgroup, and its HTML FAQ

The most affordable robot kits so far, Hero robots from Heathkit, are no longer available except secondhand. But for as little as $10 you can build a six-legged walking robot called a "Stiquito", that fits in the palm of your hand. It uses an unusual nickel-titanium alloy called 'nitinol' that directly converts the energy of a 9-volt battery into mechanical force. You can order the kit ($10), tech report ($5), and how-to video ($10) from:

Computer Science Dept, Attn: Stiquito/TR 363a/Video [specify which] 215 Lindley Hall, Indiana University, Bloomington, Indiana 47405 Checks or money orders should be made payable to "Indiana University".

IUCS Technical Report 363a describes Stiquito's construction and is available by anonymous ftp from ftp://cs.indiana.edu/pub/stiquito/ [129.79.254.191]

Questions about Stiquito should be sent to Prof. Jonathan W. Mills <stiquito@cs.indiana.edu>;. To join the Stiquito mailing list run by Jon Blow of UC/Berkeley, send mail to: stiquito-request@xcf.berkeley.edu.

comp.ai.vision comp.simulation

A critique of SimCity can be found in: Paul Starr, Seductions of Sim: Policy as a simulation game, The American Prospect 17, Spring 1994, pages 19-29.

Mark Smucker's alife home page

A nice page with alife shareware for the Mac

The basic resources on alife:

Artificial Life
Langton, Chris G., editor, (Proceedings of the First International Conference '87), Addison-Wesley, 1989.
Artificial Life II
Langton, C.G. et al, eds, Addison-Wesley, 1991.
Artificial Life III
Langton, C.G., editor, Addison-Wesley, 1994.
Steven Levy's "Artificial Life"

There's an alife newsgroup now: comp.ai.alife

CMU Oz Project. Some of the project's papers are also accessible at ftp://ftp.cs.cmu.edu/afs/cs.cmu.edu/project/oz/ftp/papers/.

An oddity that doesn't fit anywhere else: HOMR, a system for predicting what musical artists you'll like.

Artificial Morality: artmoral-list@unixg.ubc.ca This is a mailing list for discussion of Peter Danielson's book, "Artificial Morality: Virtuous Robots for Virtual Games" (Routledge, New York, 1992) and related issues. It explores theories of rational morality with Prolog. To join the list, send an email message to artmoral-list-request@unixg.ubc.ca [This list has been very quiet for some time...]


[Up: imhofaq] [Map] [Next: philosophy] [Robot Wisdom home page] (Feedback)

Search the Robot Wisdom pages:

Before you leave this site: Be sure you've checked out Jorn's weblog which offers daily updates on the best of the Web-- news etc, plus new pages on this site. See also the overview of the hundreds of pages of original content offered here, and the offer for a printed version of the site.