Haptic Interface System With 3-DOF Palm Actuator

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing haptic interface systems are limited in providing three-dimensional information, as they typically offer only one-dimensional or local information, making it difficult to effectively communicate graphical and spatial information through touch.

Innovation Solution

A haptic interface system with a manipulable shell and an actuator that moves with three degrees of freedom, allowing the user to experience the local height and inclination of a virtual object, simulating the perception of a three-dimensional surface by maintaining consistent height and inclination regardless of hand orientation, using a combination of electric motors, connection modules, and a processing unit to control the actuator's movement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a haptic device provides only one-dimensional or local information (as in mouse-shaped devices with single fingertip stimulation), then the device complexity is reduced, but the quantity of information provided to the user is limited

Engineering Contradiction:
Improvedevice complexityVSAvoidquantity of information
Core Design Contradiction:
Device complexityVSLoss of information

Solution Approach 1:

The patent transitions from one-dimensional local fingertip stimulation to three-dimensional palm-based stimulation. The actuator stimulates the entire palm surface, enabling the user to perceive global spatial information including height, curvature, and inclination of virtual surfaces through tactile feedback distributed across multiple dimensions of the palm.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The haptic interface device integrates multiple functions into a single system: it provides height information, inclination information, and curvature information simultaneously through the actuator's interaction with the palm. The device serves both as an input device (detecting palm movements) and an output device (providing tactile feedback), replacing the need for separate specialized devices.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Measurement precision

If a haptic device uses multiple degrees of freedom (as in gimbal mechanisms or flexure mechanisms), then the measurement precision of spatial information is improved, but the device complexity increases

Engineering Contradiction:
Improvespatial information precisionVSAvoiddevice complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical multi-degree-of-freedom mechanisms (such as gimbals or flexure mechanisms) with a simpler actuator system that directly stimulates the palm. The actuator's interaction with the palm's natural anatomy provides the necessary spatial information without requiring elaborate mechanical linkages, thereby reducing device complexity while maintaining measurement precision.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

Instead of physically replicating complex mechanical structures to achieve multiple degrees of freedom, the device creates a virtual copy of the three-dimensional surface information and transmits it through tactile stimulation patterns to the palm, achieving the same informational goal with a simpler physical structure.

Inventive Principle:
Principle #26Copying

3Loss of information

If a haptic device provides global spatial information through the palm, then the quantity of information is improved, but the device complexity increases due to multiple actuators and control mechanisms

Engineering Contradiction:
Improveglobal spatial informationVSAvoiddevice complexity
Core Design Contradiction:
Loss of informationVSDevice complexity

Solution Approach 1:

The patent merges the functions of multiple separate actuators into a single integrated actuator that stimulates the entire palm surface. By combining height, inclination, and curvature information into one unified tactile feedback mechanism, the device reduces complexity while still providing comprehensive global spatial information through the palm's extensive sensory surface.

Inventive Principle:
Principle #5Merging (Combining)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables users to perceive the three-dimensional relief of virtual objects through tactile feedback, allowing for somesthetic interaction and reconstruction of virtual object contours, enhancing usability for blind individuals and integrating with traditional interfaces for enriched feedback.

Implementation Method 1

The actuator (4) is constrained to the shell (2) with three degrees of freedom and is manoeuvred by a combination of electric motors

Methodology Applied
Scientific EffectElectric motor: Linear Motor

Data Source

PatentEP3152638B1A haptic interface system for providing a haptic stimulus indicative of a virtual relief
Publication Date: 2020.07.29 FOND INST ITAL DI TECH
  • EP3152638B1 patent drawingFigure 1
  • EP3152638B1 patent drawingFigure 2
  • EP3152638B1 patent drawingFigure 3~4

AI summary

A haptic interface system comprising: a shell (2) which is moved on a reference surface (Sref) by a user; an actuator (4) mechanically coupled to the shell (2), which provides a haptic stimulus on a fingertip of the user; and a motor assembly (10, 12, 14, 20), which moves the actuator (4) with three degrees of freedom. The haptic interface system also includes: a localization system (80, 82, 102, 104), which determines the position and orientation of the shell (2) with respect to the reference surface (Sref); and a control stage (70, 104), which controls the motor assembly (10, 12, 14, 20) so as to move the actuator (4) as a function of the position of the shell (2), in an invariant manner with respect to the orientation of the shell (2).