Proverbial wallets teach owners to budget

Researchers in the Information Ecology group at the MIT Media Lab have developed wallets that can shrink, expand, buzz or tighten up depending on the state of the owner's finances.

The 'proverbial wallets' use haptic feedback — a technology related to the sense of touch — to alert people if they are spending too much money.

The wallets work in conjunction with an app on the user's smartphone, which receives financial data directly from the bank. The app then sends commands to the wallets via Bluetooth. Each wallet has a different device — a resistive hinge, a vibration motor or a servo — that responds to the commands.

So far the team has come up with three prototype designs, named after the animal characteristics they most closely resemble.

Pictured above is the Mother Bear wallet, which tries to protect the money inside it. The wallet becomes harder to open the less money there is in the owner's bank account.

The Mother Bear wallet has a hinge made out of a motor that can be short-circuited. When the motor is shorted with a switch, the hinge offers greater resistance, making it harder to open.

The MIT team said in their reseach paper on the wallets that they were inspired to create them by what they saw as a "disconnection between financial decisions and consequences".

"With credit cards and online banking, our idea of money has become abstract, and the transaction experience does not reflect the amount of money involved," the researchers say in Proverbial Wallet: Tangible Interface for Financial Awareness (PDF).

The researchers stress that the wallets are not designed to prevent people from spending money. They simply provide "subtle ambient information" that in turn stokes an emotional response. In other words, they prompt spendthrifts to think twice about their purchases.

The Bumblebee wallet (above) buzzes whenever a bank processes a transaction from the owner's account.

A vibrator motor fitted in a wallet pocket generates the buzz once it is tipped off by the Bluetooth transmission.

Researcher John Kestner told ZDNet UK that human behaviour inspired the proverbial wallets concept.

"The lack of ready information on my finances when I'm making decisions is something that frustrates me, and hopefully others," Kestner said. "I brought the idea of a dynamically 'fat' wallet to a group project for the Tangible Interfaces class at the Media Lab, and we fleshed it out into the three illustrative concepts."

The Peacock wallet (above) swells and contracts to reflect the owner's bank balance. A servo within the wallet receives commands to rotate its arm from parallel to perpendicular, thus expanding the wallet's size.

Taking the peacock analogy to its logical extreme, the research group's notes say that an especially high bank balance "results in a wallet large enough to be visible to potential mates".

The proverbial wallets currently exist only as a research project, although Kestner is looking at ways of making a commercial version of the product.

"We've gotten a lot of interest from consumers," Kestner told ZDNet UK. "It's pretty close, but one hurdle is reducing power consumption — no one wants yet another thing they have to remember to charge."

To counter this problem, Kestner says the wallets will need to communicate using low-power wireless technology that is not currently found in phones. "The technology needed for a great user experience is not yet widespread," he said.

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