Pooh's Magic PlayHouse

 

Timothy Bickmore

Hao Yan

MAS 962 - Interaction Techniques for Virtual Environments

December 11th, 1998

 

 

Index

Executive Summary
Concept
Design Goals 
Design Constraints 
Design Realization
Technical Risk Analysis 
Pricing
Market Analysis 
Competitive Analysis 
Conclusion
References

 


Executive Summary

We present a design for a proposed commercial toy that is a child's play house with embedded multimedia capabilities. The house is outfitted with a flat-panel video display, video camera, microphone and speakers, VCR deck and a computer with video digitizer capabilities. This system is used to display an animated, autonomous 3D Winnie-The-Pooh character which is programmed to act as a child's personalized playmate when the child is in the house. The character reacts to the child's presence, movement and gestures using vision processing software and simple audio commands using limited speech recognition. Several play activities are possible with this basic set-up, including sing-alongs, story-telling by Pooh, story-telling by the child (with their image projected into Pooh's world and the result recorded on videotape), game-playing, and video watching.

Concept

Pooh's Magic PlayHouse is positioned to be a high-end retail toy, targeted at upper-middle-class to upper-class parents of single children aged 3 to 8. Users are assumed to already be familiar with the Winnie-The-Pooh stories as told in the series of animated movies produced by Walt Disney Corporation.

The concept for the PlayHouse is derived from the KidsRoom (Bobick, et al, to appear) and ALIVE (Blumberg and Galyean, 1995) systems developed at the MIT Media Lab, with the addition that the animated characters are highly personalized (e.g., knows the user by name, knows their schedule, etc.) and that in many activities the child's image is projected into Pooh's virtual world, rather than the character being projected into the real world of the child as in the ALIVE system. The virtual Pooh bear is designed to function as the user's virtual playmate.

The resulting system has multiple modes of operation and is extensible via software add-ons, in addition to providing the functions of  a standard playhouse and videotape player, and thus provides a potentially unlimited range of new experiences for the user.

Design Goals

The following design principles distinguish this project from existing products:

Characters as Live-In Companions

The virtual Pooh bear is intended to function as a child's personalized playmate which lives with the child in their room. It should be able to address the child by name and talk about other specifics of the child's life (e.g., birthday, favorite toy, etc.). The character should also be aware of the child's schedule and perform activities appropriate to the time of day, such as wake-up exercises in the morning and story-telling before bedtime.

Characters Aware of Activity in the House

The virtual Pooh bear should be "aware" of the child's entry into and exit from the playhouse, and their activities in the house to the extent possible, and respond to these events appropriately. For example, Pooh should greet the child when they enter the house, and if they have brought a toy into the house with them be able to comment on it ("Hi Mary, I see we're going to have a tea party.").

Customizable by Parents

Parents should be able to customize the system with the child's name and other information, in addition to the child's schedule and when they would like Pooh to wake the child up in the morning, send them off to school, or start "wind-down" activities at night. Parents should also be able to select which activities they would like to be enabled for the child and which extensions (stories, games or educational activities purchased as add-ons) they want to install.

Child Interacts in Virtual World

In the ALIVE system (Blumberg and Galyean, 1995) the user and their real environment are seen projected onto a large-screen display with virtual characters overlaid into the scene. In many activities in the playhouse, the child will interact with virtual characters in a similar manner, except that the child will be overlaid into Pooh's virtual world along with the virtual Pooh character. We feel that this provides a more compelling interaction for the child, and may eliminate any confusion about where the virtual character actually "is" (i.e., in the display vs. next to the child).

Interactions Can be Recorded

Many activities in the playhouse can be recorded on standard VHS tape for later viewing by the child or to be used as keepsakes by their parents or given as gifts to friends and relatives. Example activities which may be recorded include the child's interactions with virtual characters, the child telling stories in the virtual world, or the child singing songs (e.g., "Happy Birthday") accompanied by virtual characters.

Wide Range of Activities

Since the playhouse characters are intended to be used as long-term, live-in playmates for a child, it is important that the system provide a wide range of open-ended, non-repetitive activities. In addition to the "companion" function (which is intended to interact with a child playing with objects within the house), other possible activities include character-based story-telling (using the electronic book metaphor), sing-alongs, and directed-character games.

Extensibility

To keep the system novel and age-appropriate for a child, to avoid technical obsolescence, and to provide a steady stream of income for the inventors, the system must be extensible via add-on software or physical toys that the characters can interact with.

Educational Benefit

Some of the activities, especially add-ons, should have an educational aspect to them to increase the appeal of the system to the target market. In addition to conventional educational game software, educational cartridges could include "companion-to-child" discussions and activities on topics such as toilet training, tidiness, scholastic achievement, and other themes important to parents.
 

Design Constraints

The target age range for users (3-8) imposes several constraints on the design of the system:

 

Design Realization

Physical Design

The schematics  below show the basic design and installation of the Magic PlayHouse. The dimensions of the house are 44" x  41" x 56" tall. This standard playhouse size ensures a 3-to-8 year old child will feel comfortable playing in the house. The outside look and the internal decoration of the house will have the same style as the Pooh’s house in the Disney movies. Normal playhouses have windows on each wall. However, to get better control of lighting for vision processing, we have included only  one small window in one wall the house.

The sensing and computing devices are invisible to the child. Most of them are installed in the 6-inch-wide electronics bay behind the screen wall. The major components of the Magic Playhouse include:

Custom processing boards will be designed to perform central control and computing tasks. The two major chips in the circuits are a powerful CPU with DSP capability and a graphic chip with fast 3D rendering capability. Moreover, to support recording and replaying of interactions, we need to integrate A/D, D/A devices. A 1-gigabyte hard disk is used to store digitized video and other controlling information.

Interaction Design

 We present several specific scenarios for children’s interaction within the Magic Playhouse environment. In the following sections, we describe possible interactions, necessary perceptions and the display design for four typical scenarios -- companion Pooh, child in virtual world, game playing, and interactive storytelling. In addition to these activities, the PlayHouse VCR can also be used by the child to simply watch videotaped movies.

Companion Pooh

The system will be the child’s companion or playmate most of the time. In the morning, the Pooh bear will wake the child up and direct them through getting dressed, brushing their teeth, and doing morning exercises. In the evening, Pooh starts telling stories, singing lullabies, etc. to "wind-down" the child before bedtime. In the playtime, the Pooh bear "notices" when the child comes into the house. After a short greeting conversation, Pooh leads the child into other activities. If the child would rather play by himself/herself (e.g. having a tee party), Pooh will just sitting there and look at the child and invite the child to play games or tell a story from time to time. Pooh also has "memories" about the child’s name, habits, favorite games, stories listened, etc., so that it will prompt properly.

In the morning exercises, Pooh teaches the child some simple exercise, then leads the exercise. The vision system observes the child and gives appraisals when the child does well or gives some instruction when the kid does not do well.

In this scenario, the Pooh bear is life size (22 inches tall). It occupies most part of the screen, standing or sitting in the virtual world hugging a hunny pot. Its head and eyes move according to the child’s position change, as if it is looking at the child.

The vision system uses both cameras to detect the child’s entering and leaving the house. The ceiling camera keeps track of the child’s position, while the front camera is used to perform simple gesture recognition. The conversation in this interactive scenario is highly constrained. Most conversations are well planned and initiated by the Pooh bear, so that the system can use a template-based speech recognition system to get response from the child. By recognizing gestures, the Pooh bear can also deal with turn-taking behaviors properly.

The system will use Penny Tags to enable the virtual characters to notice tagged toys that the child brings into the playhouse. The child can tag some other toys and tell Pooh bear their name. Pooh can then notice when child brings them into the house to play and speak proper sentences about the toys. Alternatively, a line of pre-tagged Pooh toys could be sold (e.g., most of the Disney-brand merchandise) that the system would already know about. In this way, the child’s interaction within the house is even more personalized.

Child in Virtual World

At the beginning of this interaction scenaio, the LCD display acts as a magic mirror. It displays exactly the same room as the inside playhouse, except that everything in the display is cartoon style. The child’s image is projected to the proper places in the cartoon world. The Pooh bear is aware of the child in the virtual world. It stands or sits beside the child. When the child moves, Pooh also moves properly. The child can tell stories to the Pooh, sing songs along with Pooh, and do some simple ALIVE-like interactions in the virtual world.

The Pooh bear in this scenario looks smaller than it looks in the companion scenario. As shown in the picture, it has the same size with the child in the virtual world.

The whole interactive process can be saved and replayed on Pooh’s virtual TV. The child can also make a video tape of this experience, so that they can send the tape to friends or relatives as a gift.

The vision system keeps track of the child’s position, so that the child can be mapped to a proper place in the virtual world. There is also speech recognition in this scenario. The front camera is mainly used to take video input of the child.

Games

The games designed for the Magic Playhouse are mostly Role-playing and exploring style, in which the child is in control of directable characters. The look-and-feel of the display is changed to signify the change in mode, with the characters appearing much smaller and more caricatured than they do in other modes. The games are also tightly related with the Pooh stories. For example, in the "Blustery Day" story, there can be following kind of games:
The look and feel of the display is different according to the game. For example, in the "Finding house for Owl" game, the display will be an explorable Hundred Acre wood. All characters except the one the child is acting are autonomous agents. Instead of using a joystick or a stuffed animal to control the character, the kid itself become the device to control the character. The child can navigate through the woods using simple left/right gestures, observing other characters’ activities, or approaching a character for hints of direction.

Template-base speech recognition is used at the beginning of the game to obtain information about which game to play and which character the child wants to be. In the actual game playing, gesture recognition is frequently used. The ceiling camera still keeps tracking of the child’s position. Here we employ the idea of intentional control instead of direct mapping of input and output to obtain better performance.

Interactive Storytelling

At the beginning of this scenario, Pooh bear looks the same as in the companion mode. As it begins to tell a story, the Pooh bear image fades away and a story book comes out with pictures in it. The pictures gradually occupy the whole screen, which becomes the Hundred Are Woods scene.

The story proceeds from scene to scene. The child can explore each scene following the narrative. However, the theme and development of the story cannot be changed. For example, at some certain point of the story, the Pooh bear will ask the child, "Do you want to wander around this place?" If the answer is "no", the story continues. Otherwise, the scene becomes a limited explorable world, within which the child can use simple gestures to look around. When the child say "continue the story, Pooh", or after a certain period, the story continues.

Depending on the contents of the stories, there can be  other types of interactions. For example, in the "blustery day" story, the Pooh’s voice may ask the child "Mary, can you help Piglet to get to Christopher Robin’s house safely?" the child can use steering gestures to avoid stones or waterfalls in the river, and keep the right direction.

The perception task in this interaction scenario is the same as those in the game playing scenario.

Technical Risk Analysis

For a commercial product, the two most important technical risk drivers are cost and reliability. We estimate the manufacturing cost of each part of the house as well as the total cost in the next section. In this section, we discuss the reliability problem from a technical point of view.

While the vision and speech recognition components of the playhouse contribute significantly to the natural interaction via  non-invasive perception techniques, they represent relatively new and unreliable technologies.  Since a commercial product must work for all children in almost all situations, the risks imposed by this unreliability must be mitigated.
 

Vision

To maximize the reliability of the vision recognition system, we plan to control the lighting in the house and ensure that only one child at a time uses the house when the vision system is in use. This will be achieved by first detecting when more than one child is in the house (using the overhead camera) and then having Pooh or one of the other characters request that only one child participate in the activity at a time. Whenever possible, redundant control mechanisms will be used (e.g., vision and speech) to increase the overall reliability of the interaction.

Speech Recognition

To obtain acceptable recognition results, many current speech-recognition technologies require a series of training sessions which last about half an hour. This process is boring to a kid aged 3-8. Also, a general-purpose Speech Recognition engine requires a list of valid sentences that can be spoken and a large dictionary. Such a list could include thousands or even a million entries. This will slow down the recognition speed and increase the possibility of error recognition.

In the Magic Playhouse, there could be some simple conversations between Pooh bear and the child. All the conversations should controlled, i.e., the Pooh bear takes the initiative in the conversation  most of the time and expecting certain kind of responses from the child. We can implement grammar-based speech recognition based on popular speech recognition system such as IBM Viavoice. By applying Context-free grammar to the Speech Recognition engine (Microsoft), we can use rules that predict the next words that might possibly follow the word just spoken, reducing the number of candidates to evaluate in order to recognize the next word. The advantages of this method are: a) No need to train; 2) High accuracy; 3) High speed; 4) Need little resources to run; 5) Can add understanding tags so that the system can "understand" what the user say from the output of the Speech Recognition system The disadvantages include: a) Number and pattern of sentences to speak are limited; b) May increase the child’s expectation about the power of the house. Therefore, there must be some trade-off among number of grammar rules, control, and running speed

Pricing

In the table below, we give the estimated manufacturing cost of the Pooh’s Magic Playhouse. All costs listed are estimated mass-manufacturing cost (about 50~70% of the retail price). The total manufacturing cost is approximately $1,380. This may vary depending on the specific parts selected.
 
Parts
Estimated Cost
House with molded hunny pots and furniture
$ 50.00
2 12" LCD screens
$ 600.00
Color CCD
$ 30.00
Grey-scale CCD
$ 20.00
Microphone
$ 10.00
Speakers (two stereo with subwoofer)
$ 20.00
CPU (Hitachi SH-4)
$ 50.00
64MB SDRM
$ 50.00
Video card with 3D acceleration & Video capturing & TV in/out
$ 70.00
1GB hard disk
$ 80.00
VCR player
$ 50.00
Cartridge reading equipment (VCR)
$ 50.00
Penny Tag Receiver $300.00
Total
$1,380.00

The LCD display is the major cost driver. Currently, there are three major kinds of LCD display available in the market, 12"~13", 15", and 20". They cost $300, $1,000 and $5,400 respectively. The price is not linear to the size. We choose to use two 12" display, which are still cheaper than one 15" display. However, even with this option, the cost of LCD display is almost half of the total price. We expect to see a 20" product for less than $500 in two years.

Due to the low-volume / high-end market positioning, the whole playhouse could retail for $2,600 - $3,500.

Market Analysis

The target market for Pooh's Magic PlayHouse is upper-middle to upper-class American households with a single child. We feel that this market is especially well-suited for the PlayHouse, since we can play on parents' guilt of not spending enough time with their child, and on their desire for discipline and education.  Households with well-educated parents (which will likely have a large overlap with the previously described market) are also a likely target, since educated parents make up a large share of the educational toy market.

Market channels for the PlayHouse will likely include high-end toy stores such as FAO Schwarz, due to the anticipated pricing of the product. FAO's on-line catalog contains toys priced up to $40,000.00 (for a gasoline powered Lamborghini), so a $2,500 playhouse should fit into their catalog without any problem.

Competitive Analysis

We do not see any direct competition for the PlayHouse currently in the market. The closest competitors are: Barriers to competitive entry include market lead time and one or more patents on the entire PlayHouse system.

Conclusion

 Pooh's Magic PlayHouse is a technically and commercially viable interactive environment which provides a child with a virtual playmate in addition to an extensible range of activities through add-on software cartridges and an accompanying line of Pooh toys. The novelty of the system lies in the combination of a physical playspace with embedded multimedia capabilities, the use of a virtual Pooh bear as a child's live-in companion, and the ability of the system to react to the child's presence and physical activities within the playspace using non-invasive sensing technologies.

References