When a user taps, twists, or pinches a soft object, such as a cushion, a piece of clothing, or a pliable computer mouse, with HydroHaptics technology, the object will respond in a meaningful way. That could be changing the TV channel, turning off a light, or producing a digital sculpture on a screen.
The HydroHaptics sensor is driven by a small motor and employs a sealed liquid-filled chamber. This setup transmits haptic forces between the motor and user to deliver tactile sensations such as sharp clicks, vibrations, and variable resistance while keeping the surface soft and flexible.
Input from the user is sensed by the system through the object, and the user then feels the system’s haptic response through the deformable surface.
Jason Alexander, Study Lead and Professor, Department of Computer Science, University of Bath
HydroHaptics is the first of similar techniques to provide high-fidelity haptic output via a malleable surface while maintaining the surface's softness, flexibility, and input richness.
In other words, the surface remains soft and flexible no matter how you press, twist, or pinch it – something that, until now, simply hasn’t been possible.
James Nash, Study Co-Lead and PhD Student, University of Bath
Other research teams working on soft, deformable interfaces have shown varied degrees of low-fidelity feedback, less precise than HydroHaptics, or highly localized sensations limited, for example, to fingertips. To date, no prototypes have been able to match HydroHaptics’ resolution, precision, and scale.
Real-World Applications
The researchers illustrated HydroHaptics’ potential by incorporating it into four daily products: a backpack, a joystick, a cushion, and a computer mouse.
The backpack delivered smartphone notifications through shoulder touches and presses, offering discreet navigational cues. Gamers experienced physical sensations like resistance and impact using HydroHaptic joystick technology, which added a layer of realism to gameplay.
Other innovations focused on intuitive control. A soft cushion let users operate smart home devices by simply squeezing or pressing it; a silicone-domed computer mouse allowed users to sculpt digital content by physically deforming its surface, with dynamic feedback mimicking different material stiffness to guide the process.
The advancement of HydroHaptics creates exciting possibilities for intuitive, touch-based interactions with ordinary objects. Wearable technology, gaming, product design, and medical simulation are just a handful of the areas that stand to profit from the advancement.
A Tactile Tomorrow
With this technology, we can include high-quality haptic feedback in soft deformable objects and interfaces for the first time – we see huge potential for this technology across a wide range of interactive devices
Our experiments show this is a reliable system for allowing a human to interact with soft objects in a meaningful way that will enhance the way we live and work. Imagine leaning on a cushion while you’re watching TV and it produces physical effects that mirror what’s happening on screen – for instance, if a car drives over a bumpy road, the cushion vibrates, or if someone gets pushed against a hard wall, the cushion goes solid.
Jason Alexander, Study Lead and Professor, Department of Computer Science, University of Bath
He further stated, “Or picture yourself on a walk where your backpack gives you directions through gentle squeezes to your shoulder, freeing you up from looking at your phone. These are just two of the many ways this technology could be integrated into our lives in the not-too-distant future.”
HydroHaptics products might be ready for the market in the near future. To make the haptic engine appropriate for commercial use, scientists must first modify it to lower its weight.
“Last week’s conference showed us there is a lot of interest in us developing HydroHaptics further. Given sufficient resources, it wouldn’t be unrealistic for this to be in a product in a year or two,” stated Professor Alexander.
The results were presented at UIST’25: Proceedings of the 38th Annual ACM Symposium on User Interface Software and Technology, for which they received an honorable mention award.
Journal Reference:
Nash, J. et.al. (2025) HydroHaptics: High-Fidelity Force-Feedback on Soft Deformable Interfaces using Hydrostatic Transmission. UIST '25: Proceedings of the 38th Annual ACM Symposium on User Interface Software and Technology. doi.org/10.1145/3746059.3747679.