Description:

Cycling offers major benefits for health, and the environment. Making cycling accessible to more people involves addressing the main barriers that prevent people from feeling comfortable and confident on their bike. One major barrier is the discomforts many people associate with their saddle.

As an essential point of contact between user and bicycle, a saddle seeks to limit and distribute pressure placed on the sensitive parts of a rider’s anatomy. Currently, saddles come in different shapes and sizes in an attempt to accommodate the variations in pelvic anatomies. This is to reduce the discomforts of an ill-fitting saddle, such as pain, numbness and chafing. However, the anatomic differences of riders go beyond sit bone width, and include variations of pubic arch, tilt, and soft tissue.

There’s no easy one-size-fits-all solution, so the trial and error process of finding a comfortable saddle is long, expensive, and often painful. Therefore, bespoke saddles, tailored to each rider, represent the next stage in the evolution of bike seats.

VAUXEL is the output of research into the design and application of auxetic materials—a form of architected cellular lattice structure. These behave the opposite to conventional materials by expanding under tension and contracting under compression. Through this, auxetics display enhanced energy absorption, vibration damping, and localised shape conformability.

By using an auxetic saddle structure, the saddle material becomes denser under compression and flows towards the pressure points, thereby increasing structural support. The auxetic material design also enables the saddle’s padding to dynamically conform to the complex curvatures of the human body.

Pressure mapping highlights asymmetrical pressure distributions, which affect the biomechanical efficiency and comfort of cyclists. These insights are implemented into a data-driven material modelling process. By using pressure data to drive the auxetic saddle structure and material, each cyclist's unique anatomy is factored in from the beginning of the design process.

The variations of these pressure zones are reflected in the varying stiffness of the saddle material.
This combination of different zones helps to redistribute pressure onto the rider's sit bones. The material is stiffest by the contact points of the sit bones, to offer structural support. The rider’s most pressure-sensitive areas rest on the front half of the saddle. These areas of the saddle are softer, and highlighted in pink. The nose of the saddle is also soft, creating a cushioning zone when the rider switches their position on the bike, for example when leaning forwards going uphill.

The saddle features a pressure relief cut out, which is also personalised to the rider's anatomy. This helps to minimise pressure on the most sensitive central areas.

The stiffness gradients between zones are made possible through material jetting 3D printing, which enables the controlled deposition of flexible and rigid photopolymers. Voxel-level control of these micromillimeter droplets creates a seamless transition between soft and hard materials, resulting in functional material gradients that reflect the ergonomic needs of the rider.

By combining 3D printed material gradients with customised material design based on an individual's pressure distribution, the VAUXEL saddle creates a new cycling experience that embraces anatomical differences, making cycling comfortable.