HydroHaptics renders detailed haptic effects onto deformable interfaces. (A) The Hydrostatic Transmission concept for HydroHaptics utilises a hydraulic cell (A1) which couples two flexible surfaces (A2), connecting the electromechanical haptic engine (A3) and deformable interface (A4). (B) An implementation of the HydroHaptics platform, with a silicone tube interface. We developed several compatible deformable interfaces (C), including a silicone dome (C1), TPU-coated fabric pouch (C2) and TPU-printed bellows (C3). We implement these interfaces in a range of applications (D), including a force-augmented deformable 3D sculpting mouse (D1), force-augmented backpack (D2) and a 3-axis deformable force-augmented joystick (D3).
Exploded view of the Haptic Engine (left), as well as the two sub-assemblies: the Motor base (centre) and the Lead Screw Carriage (right). The haptic engine transmits rotary actuation into linear motion to control the rolling diaphragm.
The three different Deformable Interface fabrication methods: (A) Cast silicone rubber to form an elastic dome; (B) 3D printed in vase mode from TPU filament to form a harmonica design and; (C) two sheets of TPU Fabric heat-sealed to form a rectangular pouch.
The user study setup. On the left: the HydroHaptics prototype is sunken within a frame, with only the dome (B) extended above the surface. The participant is sat to the side of the frame, facing the display (A). On the right: the four gestures performed in the Deformable Gestures Recognition study. Press (A), Shear (B), Pinch (C), Twist (D).
3D Sculpting Deformable Mouse, which enables bi-directional force-augmented sculpting of digital objects. It supports force-based sculpting and deformable gestures while providing continuous, dynamic force feedback.
The “Wayfinding” Force-augmented Backpack provides tactile on-body feedback from force applied through a backpack strap, facilitating spatial and temporal notifications while integrating into an existing backpack. The white dashed line indicates the outline of the embedded TPU pouch.
Interactive Force-Feedback Cushion, that enables tactile input and feedback using a soft deformable pouch, without compromising the cushion’s original softness. The white dashed line indicates the outline of the embedded TPU pouch.
Deformable Joystick mock-up, which supports three-dimensional deformation input while providing immersive force feedback.Overview
- Conference: UIST 2025
- Type: Full paper
- Goal: Enable high-fidelity force feedback for soft deformable interfaces using hydrostatic transmission.
People
James Nash
Kim Sauvé
Catharina Maria van Riet
Anke van Oosterhout
Adwait Sharma
Christopher Clarke
Jason Alexander
Links
Abstract
Soft deformable interfaces offer unique interaction potential through input flexibility and diverse forms. However, force feedback on these devices remains limited, with pneumatic approaches lacking responsiveness and precision, while microhydraulic solutions are constrained to small form factors with limited input. We present HydroHaptics, a novel platform that enables high-fidelity force feedback on deformable interfaces via hydrostatic transmission. Surpassing current state-of-the-art methods, our approach allows fine-grained force feedback on soft interfaces, achieving a 10 N force change in < 100 ms and accurate 1 N, 10 Hz oscillation rendering. We detail the system’s design and implementation, highlighting its ability to maintain the inherent interaction benefits of soft interfaces. A user study (N = 18) evaluates the system’s performance, showing high accuracy in rendering distinct haptic effects (82.6% accuracy) and classifying input gestures (89.1% accuracy). To showcase the platform’s versatility, we present four applications illustrating HydroHaptics’ potential to enhance interaction with deformable devices and unlock novel user experiences.