CARDinality: Interactive Card-shaped Robots with Locomotion and Haptics using Vibration

TL;DR

CARDinality addresses the need for interactive tangible cards by embedding vibration-based locomotion and in-hand haptics within a thin card-shaped robot. It combines a semi-flexible PCB, BLE, IMU sensing, and four ERM actuators to realize omni-directional sliding on tables and private haptic feedback in hand, all under a unified hardware-software stack. The work provides a complete design space, a training pipeline to map motor patterns to directions, and sensing models for global state, gestures, and surface textures, demonstrated across card games, flashcards, and everyday card use. This approach expands tangible interaction into portable, customizable card form factors, enabling new game mechanics, educational tools, and assistive applications while highlighting trade-offs in robustness, noise, and retraining needs for customization.

Abstract

This paper introduces a novel approach to interactive robots by leveraging the form-factor of cards to create thin robots equipped with vibrational capabilities for locomotion and haptic feedback. The system is composed of flat-shaped robots with on-device sensing and wireless control, which offer lightweight portability and scalability. This research introduces a hardware prototype. Applications include augmented card playing, educational tools, and assistive technology, which showcase CARDinality's versatility in tangible interaction.

Figures (16)

• Figure 1: Design Space of CARDinality, divided across On-Table and In-Hand status, where each status has diverse Actuation and Sensing capability based on the affordance of cards.
• Figure 2: Other states for the CARDinality device
• Figure 3: Overall System
• Figure 4: CARDinality Robot (a) hardware overview including motor encapsulation states, (b) hardware thickness.
• Figure 5: Hardware Customization Examples