All Rise: Self-Lifting Mechanism Could Settle Toilet Seat Wars

All Rise: Self-Lifting Mechanism Could Settle Toilet Seat Wars

Because too many people sprinkle when they tinkle, a team of engineers from Boston University and MIT have developed a toilet seat that gets out of the way when not being sat upon.
Who hasn’t experienced the shudder of apprehension before entering a gas station bathroom? The only thing worse is the wave of revulsion after entering: All too often, public restrooms are a frightful mess—to put it euphemistically.

That mess can extend to the toilet seat itself, which leads to contortions to avoid touching it regardless of whether the seat is up or down.

To help remedy this situation, a group of mechanical engineering students at MIT and Boston University have created a hydrophobic, antimicrobial toilet seat that stays up when not in use.

The concept for such a product started during the Covid pandemic. “People had this high awareness of hygiene,” said Richard Li, a graduate student at MIT. “And a university is a place where messy things happen—people don’t lift the toilet seat when they’re using. We were thinking, ‘What would be the easiest way to address this problem?’”

There are many self-cleaning toilets on the market, they found. Some spin the seat under a disinfection device, others have a shelf-like washer extend over the seat between uses, others rotate a plastic covering on and off the seat after every use. But all of these had a dependence on electricity and a lot of moving parts unlikely to stand up to the attention of a drunken vandal alone in a locked stall.

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“That’s why we interviewed a lot of facility managers and maintenance staff,” Li said, “and they really hate the cost and complexity of batteries and consumables.” He and his co-founders—Max Pounanov, Kevin Tang, and Andy Chang—founded Cleana to find a purely mechanical solution that would stand up to abuse, minimize maintenance, and obviate need for electrical outlets or the hassle of replacing batteries.

The purely mechanical is, of course, a large category, and Li and his team considered and prototyped many possibilities. Above all, they wanted a seat that would stay up on its own when not in use.



“If it’s lifted, people have a bigger area to aim at and there’s less chance for things to happen, at least on top of the seat itself,” Li said. Simplicity was of the essence: A lever controlled by the feet was considered too inviting to meddlers, and any kind of geared system—something like an egg timer—too subject to failure.

Eventually they came up with a concept based on an hourglass. The seat was hollow, with water trapped inside. When it was lowered, the water would rush to the front of the seat and hold it down against the force of the springs that usually held it up. When the seat was vacated, the water would flow back slowly through a circuitous channel, delaying the moment the springs would pull it back up. It was a simple, elegant solution.

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The solution was a bit too elegant, it turned out. “We ended up giving up on that because it was not manufacturable,” Li said. “It ended up being very difficult to make a hollow seat.”

After returning to the drawing board, they came up with a mechanism that uses a suction cup to keep the seat down once it’s lowered. After a user’s weight is removed, a stream of air slowly enters the cup until the pressure equalizes, the suction cup lets go, and the springs bring it to its waiting position. The researchers also made the seat antimicrobial to further raise the sanitation bar, and they added a handle so that no one would have to come in contact with the business surface of the seat while lowering it.

Finally, they had a prototype to test out in real bathrooms.

Now, anyone reading this story who might be a woman, or live with one, may have already recognized a slight defect in the seat-up solution. 

“Our entire founding team is male,” Li said. “So we didn’t realize that, you know, women want the seats to be lowered, until after we came up with our product. And then we were talking to some female friends, and they’re like, ‘Yeah,  we don't want the seat to be lifted.’ And then we’re like ‘Holy crap, no! You’ve got to be kidding me.’”

The Cleana team had stumbled unknowingly into the toilet seat wars and into its unresolvable conundrum. It’s impossible to have a toilet seat that stays up when not in use but also stays down when not in use. 

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However, there was a glimmer of hope. In the classic formulation of the toilet seat wars the issue of who has to touch the toilet seat most is a side issue. The consequences of the seat being down, when a woman that expects it to be up (in the middle of the night, say) are obviously catastrophic. But this is an issue only for the home. No one walks into a public bathroom and assumes the toilet seat will be down already.

The solution Li and his colleagues hit upon exploits this environmental difference. 

“We decided to split it into two product lines,” he said. A seat that stayed up would be the commercial line for public bathrooms, while a seat that stayed down would be marketed for homes. 

“We call it the marriage saver,” Li said.

The stay-up commercial version is now on the market. Clients include Gillette Stadium in Foxboro, Mass., as well as Boston-area YMCAs, universities, and Roche Bros. Supermarkets. The feedback, Li said, has been great, both from users and from the people that maintain the cleanliness of bathrooms. And the residential stay-down seat will have its debut soon as well. With the spread of their product, we may all someday lower ourselves onto the toilets of the world, public and private, free of fear.

Aside from what’s on the floor.

Michael Abrams is a technology writer in Westfield, N.J.
 

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