Subject: (long) Design News AFM Article 8/12/96 (text)
From: [email-masked] (Scott Piehler)
Date: Tue, 20 Aug 1996 15:17:48 GMT
Newsgroups: rec.games.pinball

Got my copy of the August 12, 1996 DESIGN NEWS featuring Attack From
Mars on the cover. I decided to go ahead and retype/post it, since
there's a lot of good info in it, and not everyone has access to the
magazine.  (and yes, there *are* most likely typos.) I'll be
excerpting a few of the areas of this article in some smaller posts,
for some specific subjects. Here, however, is the entire article.

DISCLAIMER:
The contents of the article are copyright 1996, by Design News,
Cahners Publishing, and the author: David J. Bak, Senior Regional
Technical editor. This is the text of the article as presented in the
August 12, 1996 isssue of Design News. It is presented here solely as
a public service to the Internet Pinball Community, via the newsgroup
rec.games.pinball. For information on Design News magazine, or to sign
up for a subscription, visit their website at

http://www.designnews.com

WARNING:
Tech speak ahead! Proceed with caution. :)
Sidebar articles will be presented after the main body of text.

+++++++++++++++++++++++++++begin quoted text++++++++++++++++++++
(COVER- AFM Flyer as background. )
ATTACK from MARS! Technology causes rise in pinball-flipper fever, p.
64

(Table of contents-Picture of martian from backglass)
Meet the real pinball wizards...Page 62 (sic)

Flipper Fever!......................64
Pinball passion is back! CAD born, choreographed via software, and CPU
driven, today's game calls upon dot-matrix displays, MIDI-generated
sound, and a crazy mix of electromechanical toys to saturate the
senses and steal some time
By David J. Bak

***************************begin main article*************************
Pinball Technology-Cover Story

Flipper Fever! (logo, with a bouncing ball)
Pinball passion is back! CAD born, choreographed via software, and CPU
driven, today's game calls upon dot-matrix displays, MIDI-generated
sound, and a crazy mix of electromechanical toys to saturate the
senses and steal some time
By David J. Bak, Senior Regional Technical Editor

(Illustrations-p.64-Martian from backglass, no caption)
(p.65-photo of AFM machine, surrounded by Lyman Sheats, Brian Eddy,
Doug Watson, Adam Rhine, Robert Friesl, Brian Morris, Dan Forden &
Roger Sharpe)
(CAPTION)-Modern games require the multiple disciplines of mechanical,
electrical, software and sound engineers, as well as the creative
skills of an art team.

*New York City*-Back arched, one bare foot resting against the other
leg's calf, 26 year old Lyman Sheats analyzed the playfield,
evaluating risk vs reward. Simply playing the path of least resistance
would not do, not in this, the final game of the 1993 PAPA
(Professional/Amateur Pinball Association) World Championship
Tournament.

Sheats-then a software engineer working for Mitre Corp., Bedford,
MA-had methodically marched through the international field of
contestants, making it to the final group of four. Steadily building
points towards a final crescendo, he captured the championship round
to win the tournament's trophy, $3,000, and the admiration of an
awe-struck Roger Sharpe, who labeled Sheats "a one-legged impresarion,
the most highly focused and disciplined pinball player I've ever
seen."

Sharpe should know: A tourney participant and pinball devotee who's
played every game that's ever been built since 1967, he literally
wrote the book on his favorite subject (Pinball! 1977, E.P. Dutton).
Now-a-days, Sharpe and Sheats battle it out head-to-head during coffee
breaks at Chicago's Williams Electronics Games complex, where they
help design new games for tomorrow's champs

*Mini theme parks.* Haven't played the silver ball lately? You're in
for a surprise. Pinball in the '90's offers a high-tech playfield,
jam-packed with interactive electromechanical and solid state devices,
multi-level ball tracks, plus a wild variety of sound and lighting
effects to simulate earthquakes, tornados, and other natural or
man-made mayhem. The back glass, more often than not, celebrates hit
movies like Twister. Even the actors get involved, their voices
immortalized in pinball history. After all, what's Terminator without
Schwarzenegger?

Yet, there's more to pinball than meets the eye. It's the guts of the
machine that makes today's thematic approach possible. More than 1,000
components, for example, bring life to Attack From Mars, the latest
game from Williams, maker of Bally/Midway amusement games. Designing
these parts into a tight package, under stringent cost and time
constraints, requires the dedicated attention and teamwork of at least
five engineers over a nine- to twelve-month span.

"The days of switches and ramps, simple things that could be handled
by a set of relays, are long gone, " says Brian Eddy, Attack From Mars
game designer. Modern games, he explains, transcend the
serial-progression, single player game of the '60s and early '70s.
"Now we write a driver for every mechanism, and tie them all into the
game's operating system." The result: memory and recall, allowing
head-to-head and multi-player games.

As principle designer and project leader, Eddy selects the game's
story line, making sure it is cross-cultural and recognizable world
wide. Additionally, he specifies all the electromechanical mechanisms
and oversees project development. Standard play features, such as jet
bumpers and slings, are balanced against new toys like the Martians'
flying saucer. "We don't want customers walking up to a new game and
saying 'I've seen that before',"Eddy notes.

Likewise, the designer doesn't want the play lasting too long. "A game
should take about 2 1/2 to 3 minutes," says Sharpe, director of
licensing. Each ball should average 47 or 48 seconds, and players
should win a free game approximately 25% of the time."

Once he has selected the toys, Eddy lays out the playfield on a
networked AutoCAD system. Care is taken to distance the targets up the
incline, or place them along the outside of the playfield to preserve
their life without slowing the action. Integrating ball paths and
ramps rounds out the play, making the game's overall objective
achievable. Eddy likens the design process to squeezing a Disney or
MGM theme park into a standardized space. 

"You're always thinking of new things the ball can do,: he points out.
For example, "we might want the ball to be caught between two magnets
mid air, spin around this thing, and shoot out that way. Even if we
can't make it happen, the process of trying often leads to something
we haven't thought of before; that's the excitement of the engineering
that goes into these games."

And *that* makes Bob Friesl "Mr. Excitement." As project engineer, he
designs the toys or mechanisms Eddy envisions while laying out the
playfield. "The CAD plot I receive from Brian gives me the physical
envelope for each mechanism, " explains Friesl, a former design
engineer with Schwinn Bicycles and the fitness product industry. 

*Geometry and kinetics.* Friesl designs a particular mchanism and its
controller using traditional engineering practices, "because you can't
look the part up in a catalog." Each device-and there are
approximately 150 of them in a game like Attack From Mars-must stand
up to an extremely hostile environment: temperatures easily reach
120F, given the abundance of electronics; the balls generate
substantial dirt and grime over time; and vibration is a constant.

Every mechanism requires careful analysis of bearing and shaft loads,
ball impact, and weld sizes-"real engineerring work," states Friesl.
"From the operator's point of view," adds Promotion Manager Patrick
Fitzgerald, "even one day down is unacceptable; it's a day of quarters
not collected."

Once the mechanisms are detailed in 2D, engineers convert the drawings
into 3D solid models using SDRC I-DEAS software. They then use these
models to generate codes for stereolithography and machining.
"Eventually, " Friesly predicts, "we will design in solid models to
further speed the development and prototyping process."

Three-dimensional models also serve to generate the foam-core or
plastic blanks located on the game's white wood-a "shot proving"
plywood mockup. That way, Eddy verifies the game's dynamics, making
sure the ball moves between the flippers, bumpers, ramps and targets
in the desired fashion, utilizing the entire playfield. The white wood
also helps determine placement of protective shielding or extra
mounting braces to withstand the continual pounding of the ball.

*Beyond video.* Pinball enthusiasts tend to regard video games with
disdain, not because they aren't challenging the first time around,
but because their pattern of play can be memorized and mastered.
Pinball, on the other hand, is like life itself: you rule a game one
day; it bends you over the next. 

The game's resurging popularity, however, owes a nod to video. Without
a central processing board and proprietary operating system, memory
and recall would not be possible. In fact, modern pinball games won't
work without programming.

"If there is no software, and I load a ball into the eject slot, it
just sits there," says software designer Sheats. "One of the first
steps the programmer must do is ensure that the player can kick the
ball onto the playfield and have it return." The procedure, Sheats
says, is to program-via assembly language-an instruction set that
triggers a solenoid whenever a player activates the eject switch. 

Once the game is "flippable," Sheats writes drivers for each of the
electromechanical mechanisms. Standars devices like sling shots and
thumper-bumpers (targets that provide rebounding action and sound)
come free with the operating system. Non-standard mechanisms, like the
shaking saucer, require special programming. This is what tailors the
operating system to a specific game.

"It's important that Lyman and I work together early on," states
Friesl, "because I have to create stuff that our software can suport."
Programming a moving device, for example, requires hardware able to
read the optical encoder on the motor shaft and count the ticks.
Otherwise, "we don't know where it is at any given point in the x - y
plane."

Other ways the programmer helps keep the quarters coming:
* Write software that will recognize a beginner, occaisonally
rewarding the player with an extra ball, " in a subtle way to make him
or her feel it was earned."
*Develop on-board diagnostics
*Build "stacked conditions," or multiple events that give the player
the chance to double, triple, or even quadruple the reward level.
*Create game rules and choreograph sound, light, and dot-matrix
displays.

*Lights and music, please* Brian Morris and Adam Rhine create
animations for the game's dot-matrix displays, helping bring the
storyline to life. Similarly, Dan Forden, the Attack From Mars sound
engineer, creates the game's music and sound elements, utilizing a
data compression sound board that can run as many as six tracks
simultaneously. 

Forden pieces together various sound effects and music using
sequencing programs and digital audio editing on a Macintosh to
control an arrray of different synthesizers through MIDI (Musical
Instrument Digital Interface); Sheat's software programs subsequently
tie them to specific game events.

"We need to generate certain sounds for specific shots," says Forden.
"For Attack From Mars, we tried to adapt the campy audio of the
1950's-era science-fiction movies." What about the horrible gross
noises emanating from the aliens themselves? "We taped Doug!" Forden
laughs. 

Credit Doug Watson, Attack From Mars art director, not only with the
Martian voices, but with the games overall look and intuiteveness. "My
job as the artist," he explains, "is to work in conjunction with the
programmer, the designer, and the sound engineer, to personalize each
shot. Networking these shots graphically makes the game
understandable."

*From Soho to Brighton* Pinball draws a vast diversity of players the
world over. Steve Epstein, owner of New York City's Broadway Arcade
near 52nd Street, and PAPA tournament founder, sees them all- from
celebrities and tourists, to regulars stopping by for a breather after
work. He attributes the game's enduring popularity to its live action
and unpredictability, recalling an old saying that "the ball is wild."

Maybe so. But for the design engineers, it's the little steel sphere,
2.8 ounces and 1 1/16 inches in diameter, that remains constant;
everhtying else is wild.

************************end main article body***********************

###########begin sidebar articles################

(SIDEBAR ARTICLE-Page 66)
FLYING SAUCER,  ANGRY ALIENS

(Article accompanied by diagram of oscillating saucer, and one of a
*bouncing* martian)

Many of the electromechanical devices built into Attack From Mars are
unique to the game and must be designed from scratch. For example,
striking the flying saucer with the ball represents a missile attack
against an alien ship.

The target, when hit, transmits a signal to the CPU. The processor, in
turn, sends an electrical impulse to the solenoid. Energizing the
solenoid retracts its armature, impacting the rubber bumper to
oscillate the saucer. The electrical impulse to the solenoid is
accompanied by activation of a Xenon strobe light, flashing lights in
and around the flying saucer, and various sound effects. 

Likewise, the CPU sends an electrical pulse-varied in magnitude and
duration-to solenoids that shake the Martians. Made from a low
durometer rubber, these aliens appear to be jumping up and down,
shaking their fists.

(SIDEBAR ARTICLE-Page 67)
TIMELINE FOR DESIGN
(A bulleted timeline, with a streaking pinball graphic)

*1871 Cincinatti's Montague Redgrave invents a game which features a
spring-powered plunger and playfield

*1928 "Billiard Skill" First game to propel steel balls onto a flat
playfield

*1932 Invention of the pinball "tilt" mechanism

*1933 Electricity is introduced to playfield. Also: first automatic
payout game where players can win cash with high scores.

*1937 Pinball bumpers appear, adding more speed, excitement, and
unpredictability

*1941 New York City bans pinball, initiating anti-pinball campaigns
across America

*1947 The "flipper" is introduced to emphasize the game's skill aspect
and break association with gambling machines

*1948 First machine with flipper pair at bottom of playfield

*1975 Hybrid pinball/video games appear. 

*1976 NYC and Chicago legalize pinball.

*1978 Pinball incorporates solid state electronics

*1980 Multi-level playfields introduced

*1991 Dot-matrix displays first incorporated

*1993-Implementation of digitally compressed sound. 

(SIDEBAR NOTE-Page 68)
Pinball accounts for an almost 40% market share of the $8 billion
coin-operated game industry, worldwide.

(SIDEBAR ARTICLE-Page 68)
ARCADES AND ALGORITHMS

To keep audio on par with the computer-controlled playfields of
today's pinball machines, Williams Electronics Games, Inc. recently
developed a sound system called DCS, for Digital Compression System.
The DCS sound board delivers six channels or 16-bit digital audio for
near CD sound quality. Additionally, independent control over the
volume, looping, and playback of each channel in response to game
commands provides interactivity. A game typically uses one channel for
music, and the others for sound effects and speech.

The biggest limitation with most game and multimedia sound systems is
storage. For example, 16-bit digital audio at a rate of 31,250 samples
per second requires about 60 kbytes of storage per second (a data rate
of 500 kbits/sec). Durability requirements dictate the use of ROM for
storage of code, images, and sound in arcade games, while the overall
cost of the game limits the ROM available to about 3 Mbytes. The
problem is that 3 Mbytes of ROM at 60 kbytes a second is only enough
for about one minute of total sound. Most Wiliams games have between
10 to 15 minutes of non-repeating sound. 

Solution: a propritary, transform coder algorithm that reduces a 500
kbit/sec data rate by a factor of ten or more, and runs on a low cost
DSP chip. This algorithm is similar to to those used in the Sony
MiniDisc format, the Phillips Digital Compact Cassette, as well as
emerging digital sound formats for cinema.

DCS hardware is relatively simple. Major components include the
surface mounted DSP chip, eight sockets for ROM, a 16-bit mono DAC,
and an audio power amplifier. All this fits on to a two layer printed
circuit board measuring about eight inches square. 

The low-cost DSP chip-a DSP-2105, manufactured by Analog Devices, runs
at 40 MHz and executes more than 10 million complete instructions per
second. Three 2-kbyte SRAMs supplement the on-chip RAM These are
mapped into both program and data memory space, and are used primarily
as temporary storage for the real-time decompression and the inverse
FFT (Fast Fourier Transform) operations required for each of the four
playback tracks.

A bi-directional, 8-bit interface connects the soundboard and the game
host. Playback commands from the game host consist of numbers which
the DCS operating system uses as indexes into tables of playlists. One
command can trigger anything from a single sound effect to a segment
of music that loops indefinitely. Conversely, the sound board can send
timed data back to the game host, which is useful for synchronizing
animation, display effects, and light shows with music.

#################end sidebar articles#######################

+++++++++++++++++++++end quoted text+++++++++++++++++++++++++++++++

Whew!

Scott

Scott Piehler- Atlanta, GA
A list of newer pins in the Atlanta area can be found at
http://www.mindspring.com/~rosco29/pinball.htm