At Expo 2025 Osaka, visitors to the Swiss Pavilion were treated to a spectacle unlike any other: a robotic wedding cake, complete with dancing gummy bears and powered by edible rechargeable batteries.

Dubbed the RoboCake, this culinary marvel is the brainchild of researchers from École Polytechnique Fédérale de Lausanne (EPFL) and the Istituto Italiano di Tecnologia, developed in collaboration with food scientists and pastry chefs from EHL Hospitality Business School.

Towering tier by tier, the RoboCake is more than just a dessert—it’s a functioning edible machine. At the summit, two vibrant red gummy bears perform a whimsical dance. Crafted from gelatin, syrup, and food-grade colourants, these sweets are animated by a cleverly designed pneumatic system. Tiny channels within their gelatinous bodies allow air to pass through, making their arms wave and heads tilt with a lifelike charm.

The choreography is more than simple mechanics—it’s synchronised with a rotating series of dark chocolate discs embedded in the cake’s base. These discs are the true technological breakthrough. Developed by researchers at the Istituto Italiano di Tecnologia, they represent the world’s first edible rechargeable batteries. Made from vitamin B2, quercetin, activated carbon, and rich dark chocolate, they’re entirely safe to eat and surprisingly flavourful.

In addition to powering the gummy bear dance, these innovative chocolate cells also light up miniature LED candles scattered across the cake’s layers. Each glowing flicker is a testament to the potential of merging food with functional technology. As the cake is sliced and enjoyed, guests experience a wave of rich chocolate taste followed by a subtle tang from the edible electrolyte, creating a unique multisensory journey.

Though currently a showpiece, the RoboCake hints at a delicious future—where food entertains, innovates, and even powers itself.