KAVIS

3D Printed Bike Saddle

As is well known among cyclists, the saddle is one of the most important components of a bike. Many variables can influence the comfort of a saddle such as body anatomy, position on the bike, individual flexibility, and the type of terrain. To guarantee maximum performance, the saddle must adapt to the athlete, ideally, each person should have a seat tailored to its specific characteristics. We have therefore reflected on how it is possible to make this object adaptable to the widest possible audience and how to configure the form in a manner to encompass different qualities in a single body. The softness of padding, the rigidity to sustain the body, the porosity to provide ventilation. The use of 3D printing in the production of the saddle brings these benefits and more. The use of a multi-material voxel printing process allows manufacturing an object with different mechanical properties within the same body in a seamless way. In the specific case,  the saddle's rails are rigid, stiff nylon, the same thing for the spine of the saddle. The material then changes in the rest of the object, becoming a soft rubber. In other words, there is a material transition from the part connecting to the bike's frame to that one touching the cyclist's body while maintaining the formal continuity.

The model of the saddle is built on a series of construction curves. The adaptation of these curves allows reconfiguring the general shape, generating in this way its volume. A modular element is diffused in the volume and adapted to fit the specific sector. The module is based on a Hybridization between two types of minimal surfaces(1): the Schoen's Batwing Surface and Scherk's Saddle tower surface(2). This specific geometry confers rigidity to the system, especially in the parts where the material is rubber. The combination of the geometrical configuration and the material are providing a "spring effect". The elastic properties give more comfort without the need for upholstery or additional materials.  The modular cellular composition is parametrically generated allowing the configuration to meet specific variables such as cycling position and desired flexibility. A different repetition of the module corresponds to a different density of the volume: a higher density of its distribution will build higher structural performance, therefore increasing the rigidity of the object.
The cavities generated by the surface articulation are beneficial also to drive airflows through the saddle, enabling in this way natural ventilation of the contact surface.

 As a result, we have a wide range of customizations and the opportunity to get the best performing product possible by working on a synthesis between shape and material.

 

(1) A minimal surface is a surface that minimizes the total surface area, in other words, the surface has the smallest possible area spanning the boundary. Soap films are minimal surfaces.
(2) http://facstaff.susqu.edu/brakke/evolver/examples/periodic/batwing.html http://virtualmathmuseum.org/Surface/saddle_tower/saddle_tower.html