HOBERMAN - Transformable design
Tartu, Estonia
Aha! It expands! Hoberman has installed one of our expanding spheres in the largest science museum in the Baltics – the recently completed AHHAA Science Centre in Tartu, Estonia.

Established by the 370-year old University of Tartu, AHHAA’s goal is to make science education approachable and entertaining for everyone. AHHAA has been organizing public interactive science exhibitions in Estonia and internationally since 1997 – a tradition of scientific excellence that is continued with the installation of Hoberman’s Expanding Sphere.

Suspended within the Science Centre’s large, centrally-located domed atrium – a busy and lively exhibition space filled with a range of interactive technologies and exhibits – the aluminum sphere continually grows and shrinks to create a dynamic centerpiece.

Visitors can witness the spectacle from multiple and changing perspectives – from directly beneath on the atrium floor or eye-level along a second-floor catwalk, even while riding up and down in a human-powered harness lift. Arguably the best and closest view is experienced from the seat of a bicycle perched upon a tight-rope wire stretched across the space – Riders can cycle through air across the atrium and pass directly by the sphere as it magically expands out towards them. Fun and whimsy are fully at play at AHHAA, and the kinetic, pulsating Expanding Sphere feels right at home.

Starting at 1.5 meters in diameter, the sphere is capable of expanding up to 5.9 meters in diameter in approximately three seconds. Weighing 340kg, it consists of 244 hubs and 1,440 linkages machined out of aircraft-grade aluminum, and connected with 2,880 pins and 5,760 bearings. Hub-linkage sub-assemblies form triangulated facets, with the entire sphere approximating the geometry of a geodesic sphere. Twin actuator cables control the diameter of the sphere by alternately pulling the sphere’s opposing polar hubs, being controlled by a single cable winch and a single servo motor.

Hoberman, through its joint-venture Adaptive Building Initiative (ABI), created a second installation for AHHAA Science Centre’s conference room – a dynamic glass wall utilizing ABI’s Adaptive Fritting technology to provide adjustable opacity.
Learn more about the project.