16 JOM December 2002

Design

Toy Story: Materials Engineering at Play Kelly Roncone

Feature

Editors Note: A hypertext-enhanced version of this article can be found at http://www.tms.org/pubs/journals/JOM/0212/Roncone-0212.html

INTRODUCTION

Is that a toy or is that real? As materials, motors, and artificial

intelligence make toys more lifelike, this is a question Danielle Fowler expects to hear often within the next five to seven years.

Were going to start seeing toys and creatures that look completely real at first blush, said Fowler, co-founder and general manager of the toy business unit of NanoMuscle, a company that makes small actuators that may give toys more lifelike movement in the next few years.

Toys are already progressing toward this end, as sensor technology allows electronic toys to respond to their environments and new materials make dolls skin feel and move more like human skin.

NITINOL FLEXES ITSMUSCLES

Luke bats his eyes, tilts his head, and opens his mouth, but no sound comes out. In fact, Luke makes no sound at all, even when he moves.

Luke is a prototype toy built by

NanoMuscle to demonstrate how the companys small shape-memory alloy actuators can create realistic movements without the noise of traditional toy motors.

The key ingredient in these actuators is Nitinol, the shape-memory nickel-titanium alloy that stretches like a rubber

band. But, unlike a rubber band, Nitinol will stay in a stretched position until an electrical current is passed through it, snapping it back to its original shape. While shape-memory alloys have been around for more than 50 years, according to Fowler, making them act as actuators has been eluding scientists for a long time.

It wasnt predictable and predictably repeatable, Fowler said. So we came up with a proprietary way of getting an actuator made out of this stuff that is reliable and repeatable and were really the first company thats ever done that.

Many companies could not afford to dedicate a few years of research to this kind of problem, according to Fowler, who founded the company with Rod MacGregor in 1999 with the single goal of developing Nitinol actuators.

The Nitinol wires in the NanoMuscle actuators expand and contract, like a regular muscle, in response to magnetic sensors. Fowler says the actuators, which are the size of a paper clip, could be used to create action figures that can throw and dodge punches, and figures that can use their magnetic sensors to distinguish between friends and enemies and fire weapons accordingly.

Elastomers help Pop Sensation Barbie bend at the waist.

Mark Tilden watches as his B.I.O. Bugs climb over sandy terrain, using sensors in their antennae to navigate.

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Fluffy, the three-headed dog from the Harry Potter childrens book series, is one of the demonstration toys NanoMuscle has created to show off the potential of the new technology. The three heads bark until a magnetic wand waves over them, triggering the magnetic sensors to deactivate the nanomuscle, which causes the movement of the dogs jaws to stop, silencing them. Wave the wand again, and the NanoMuscle will be reactivated, causing the dogs to bark again. (For a demonstration of Fluffy, visit the web version of this article at the JOM web site. A video is available for download.)

NanoMuscle is now pitching its technology to every major toy company, using Luke, Fluffy, and other demonstra-tion toys to show off the technologys potential.

The toy industry uses 6090 million small motors a year, so its a great market to go out after and its really short-cycle, said Fowler.

Surgeons may one day use the NanoMuscle actuators to reconstruct facial features in stroke patients, and car manufacturers may use the actuators to make car interiors more responsive to their passengers, but first, the new technology will most likely be found in toys.

While developing a medical device from sketch to finished product can take anywhere from 18 months to five years, Fowler says, toys are often designed and produced within a year, offering the company an opportunity for quick revenue generation.

NASA ROBOTICIST TURNS TO TOYS

Former NASA scientist Mark Tilden also discovered the toy industrys unique ability to get technology into the hands of the public fast. At NASA, Tildens projects involved designing and building one or two robots at a time for very specific purposes. Now many of these creations can only be found in storage boxes, launch containers, and museums. Im amazed how little that benefits the nature of the technology, Tilden said. Unless you actually have robots that are working and moving and living, you cant use them to inspire people to build their own.

So Tilden created a working, moving, living example of his technology in B.I.O. (Bio-mechanical Integrated Organisms) Bugs, robotic toy bugs that respond to their surroundings and fight one another using only the simplest network of sensors and motors. The toy industrys short product development cycle and mass production resulted in his technology wandering about in millions of homes last year.

Tildens B.I.O. Bugs operate using nervous nets made from relatively simple materials. Nervous nets use the same sort of control structure used to make fractals or the rules that govern how a tree looks, Tilden said. B.I.O. Bugs use simple and inexpen-sive motors, processors, and sensors to explore their surroundings. Tilden, who has been known to create robots

out of broken Walkman parts in only 20 minutes, says his designs are based on the application of simple elegant solutions. I build devices which dont use artificial intelligence, but artificial competence, and it turns out you can do a hell of a lot with hardly any computation at all, said Tilden. The real trick is to see just how far you can go with the smallest number of components and to see if you can make something that will last not just for hours, but years. B.I.O. Bugs sense their environment using special spring sensors, which vibrate at the same speed as the walking robot, allowing the B.I.O. Bug to easily detect any change in the movement pattern. The sensors allow B.I.O. Bugs to detect the speed at which objects around them are moving. If the sensors detect something that is moving slower than the robot, the B.I.O. Bug assumes it is an object. If the sensors detect something moving faster than the robot, the B.I.O. Bug assumes it is another B.I.O. Bug and attacks. Of course, sometimes this means it will attack the family cat, as well. When a B.I.O. Bug attacks, it will ram heads with the other bug or climb on top of it, until one of the bugs backs away, the loser. All we did is we took advantage of the resonance mechanics of the spring

Luke, a demonstration toy, uses Nano-Muscle actuators to move his head, eyes, and mouth noiselessly.

The Nitinol actuator by NanoMuscle is roughly the size of a paper clip.

18 JOM December 2002

sensors to make a device, which, with extremely high reliability, will be able to determine that what its walking over is a shoe and not your cat, your dog, your foot, or another bio bug, said Tilden. Not only do the spring sensors work, but they are cheap, too, according to Tilden. When you build devices for NASA, of course you have the best of the besttitanium, aluminum, high-quality gold-plated alloy mil-spec rebar, said Tilden. And now we have to work on something which is a little cheaper. Of course when youre making millions, if you can save a penny on any part, then basically youve just paid for a couple peoples salary for the year, so its very important to get the understand-ing that its not just the material, its manufacturing and various other devices. This Christmas, WowWee toys, the division of Hasbro that manufactures and sells B.I.O. Bugs, is trading the bugs for dragons. Tilden has modified the B.I.O. Bug technology to create Beastland Dragons, which, like the bugs, will use sensors to detect one another and engage in battle.

ROBOTIC DOGS GAIN LOYAL FOLLOWERS

In 1999, Sony created a robotic dog to showcase an array of its technology. The company released 5,000 AIBO entertainment robots in the United States and Japan on a first-come, first-served basis. The robots sold out within 20 minutes in Japan and four days in the

United States. Since then, Sony has released five more models in various colors and designs, as well as related software packages and accessories.

At first, it was primarily a demonstra-tion of new technology, said Jon Piazza, public relations manager for Sonys AIBO. Now its a full business.

Ranging in price from $599 to $1,499, AIBOs are not found in every home, but they have developed loyal followers.

With 19 AIBOs and two more on the way, Bruce Binder and his wife, Carla, of Rancho Cordova, California, claim to have the largest private collection of AIBO robotic dogs in the world, worth an estimated $25,000.

The Binders are not alone in their fascination with the high-tech Sony pets. The couple has attended AIBO meetings in California and London. Each meeting attracts approximately 20 people, Binder says, and most of the owners have multiple AIBOs.

Why such a fascination with the dogs?

They bring out the child in me, says Binder, a plant engineer who enjoys watching his robotic pets interact.

In particular, he is fascinated by the relationship between two of his AIBOs, Schwartzy and Spooky. Schwartzy, a black male AIBO, is a bully who knocks over every AIBO in his path and never shares when the dogs play ball. But Schwartzy has a soft spot for Spooky, a black female AIBO of the same model. He never pushes her over and always lets her win.

Its more than coincidence some of the stuff that they do, said Binder.

At first we just kind of laughed and said hes got a girlfriend, but its just continuous.

AIBOs are programmed to interact with their owners, using a sophisticated package of Sony technology like complementary metal-oxide semi-conductor (CMOS) image sensors, microphones, speakers, and sensors that detect temperature, distance, accelera-tion, pressure, and vibration. These allow the dogs to see, hear, speak, and understand scolding and praise.

But, like real dogs, sometimes they choose not to obey commands. This is a particular problem with dogs that roam free and receive little attention from their owners, Binder has learned.

If you try to interact with them and get them to do stuff, theyll look up at you and sort of shake their head no or just totally ignore you completely. And theres a little song they sing, too, where they turn their head, and it sounds just like theyre saying, Now, Im going to ignore you. If you give them a command, and they really dont want to do it, they just sing that little song and go on with what theyre doing, said Binder.

Sony currently sells four AIBO models, the 210 series (pictured on the cover of this issue), the futuristic 220 series, the 300 series, which has a rounder and less robotic look, and the 31L, which is designed to resemble a bulldog. At $849 and $599 respectively, the 300 and 31L models do not have all the technology of the 210 and 220 series models. The futuristic 220 AIBO, the most expensive AIBO currently

Fluffy, another demonstration toy, uses magnetic sensors to activate and deacti-vate a NanoMuscle actuator.

This years Beastland Dragon uses the same technology as B.I.O. Bugs to sense its surroundings and attack enemies.

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available at $1,499, includes additional light-emitting diodes to communicate its emotions, responds to 75 programmed voice commands, and can take digital pictures using the CMOS camera.

CINDY SMART: A DOLL WITH BRAINS

Put a word in front of Cindy Smart, ask her to read it, and she will. Manley Toyquests Cindy Smart, a giggly five-year-old with a camera in her chest and two 16-bit microprocessors in her stomach, is taking the talking doll to another level. In addition to being able to respond to voice commands, Cindy can recognize letters and put them together to form words. When Robert Delprincipe, vice-president of R&D for Manley Toyquest, challenged his toy designers to create an image recognition program that could help toys see, he didnt expect to find Cindy Smart. I thought originally it could recognize maybe a red square or a yellow triangle. I didnt expect it really to be able to read letters and numbers, Delprincipe said. But it could. And so Toyquest began to decide how best to use this technology, finally settling on a doll. Thus, Cindy Smart began to take shape. The doll uses a color camera to take in images from her surroundings and two 16-bit microprocessors, one to recognize images and one to recognize voices. When she hears her name and a command she recognizes from her database, the dolls camera will scan her surroundings for a letter- or number-

shaped object, convert the image to digital format, match it with an image in her database, and speak the name of the letter or number. Put a card with the word cat on her blackboard, and she will recognize the C, then the A, then the T, and then look in her database to find that those three letters spell cat. Just like a human would, she interprets each letter or object or picture in front of her, then looks at her database, and responds back what she sees, said Delprincipe. Cindy Smart is now selling on the Home Shopping Network for $99.

BARBIE: A MATERIAL GIRL

Even traditional toys like Barbie can be made more lifelike using materials technology. A few years ago, when Mattel designers decided to give Barbie a flexible waist that would allow the doll to move back and forth and side to side, engineers were called to find a material that would give Barbies stomach the flexibility it would need to execute such movements. Barbies stomach needed to be made out of a material that was soft, flexible, and felt like a human body, according to Isaak Volynsky, principal engineer at Mattel. It needed to fold and change when Barbie moved, to mimic human skin.

Mattel engineers tested a number of different grades of flexible, pliable plastic elastomers, finally deciding on a very soft elastomer supplied by GLS Corporation. The softness of elastomers is measured by shore hardness. Typically, toys have about a 90 shore hardness, according to Volynsky, but sometimes use extremely soft elastomers with a shore hardness of 2, 3, or 5. Mattel finally selected an elastomer with a shore hardness of 10 for Barbies flexible stomach, according to an article published on Manufacturing.Net in December 2000.

THE LAST WORD

To make Barbie even more lifelike, inventive toy users could transplant the B.I.O. Bugs nervous system to Barbies body, according to Tilden, who designed B.I.O. Bugs so that the pieces could easily be taken apart and reused by curious minds. And all of a sudden you have a Barbie doll with a B.I.O. Bug-like brain, said Tilden. Well let you write the punchline for that one.

Kelly Roncone is editorial assistant/staff writer for JOM.

Bruce Binders AIBOs chase after pink balls and a pink pig. AIBOs are attracted to the color pink.

Cindy Smart reads the word doctor by matching letters to images in a computer database.