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Wearable wireless tactile display for virtual interactions with soft bodies.

Frediani G, Mazzei D, De Rossi DE, Carpi F - Front Bioeng Biotechnol (2014)

Bottom Line: The device was based on dielectric elastomer actuators, as high-performance electromechanically active polymers.The actuator was arranged at the user's fingertip, integrated within a plastic case, which also hosted a compact high-voltage circuitry.We present the structure of the device and a characterization of it, in terms of electromechanical response and stress relaxation.

View Article: PubMed Central - PubMed

Affiliation: School of Engineering and Material Science, Queen Mary University of London , London , UK.

ABSTRACT
We describe here a wearable, wireless, compact, and lightweight tactile display, able to mechanically stimulate the fingertip of users, so as to simulate contact with soft bodies in virtual environments. The device was based on dielectric elastomer actuators, as high-performance electromechanically active polymers. The actuator was arranged at the user's fingertip, integrated within a plastic case, which also hosted a compact high-voltage circuitry. A custom-made wireless control unit was arranged on the forearm and connected to the display via low-voltage leads. We present the structure of the device and a characterization of it, in terms of electromechanical response and stress relaxation. Furthermore, we present results of a psychophysical test aimed at assessing the ability of the system to generate different levels of force that can be perceived by users.

No MeSH data available.


Related in: MedlinePlus

Experimental setup for the mechanical and electromechanical characterization tests.
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Figure 4: Experimental setup for the mechanical and electromechanical characterization tests.

Mentions: Assessment of the static electromechanical performance of the tactile display was obtained by measuring free stroke and blocking force at the apex of the passive membrane. For different driving voltages, stroke and force were measured with a double-column dynamometer (Z005, Zwick Roell, Germany) according to the procedure described in Carpi et al. (2011b). In particular, a cylindrical indenter was mounted on the mobile crossbar of the machine, attached to a load cell. The indenter had a diameter of 12 mm, so as to fit with the internal part of the plastic case of the device. The crossbar was then moved, until the load cell detected a contact between the indenter and the actuator’s passive membrane, as shown in Figure 4. Then the actuator was electrically driven, so as to cause a displacement of the membrane’s apex. After that, the tool was brought in contact again with the actuator. The distance covered to restore contact was considered as the active displacement (free stroke). Subsequently, the voltage was turned off, without changing the position of the tool. As a result of this, the relaxation undergone by the actuator while trying to recover its rest shape generated a force, whose steady-state final value was considered as the blocking force. Finally, the crossbar was brought back to the initial position, and the actuator was allowed to fully recover its original shape. The test was repeated for voltages up to 4.5 kV, which was used as a safe limit to avoid electrical breakdown.


Wearable wireless tactile display for virtual interactions with soft bodies.

Frediani G, Mazzei D, De Rossi DE, Carpi F - Front Bioeng Biotechnol (2014)

Experimental setup for the mechanical and electromechanical characterization tests.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4150388&req=5

Figure 4: Experimental setup for the mechanical and electromechanical characterization tests.
Mentions: Assessment of the static electromechanical performance of the tactile display was obtained by measuring free stroke and blocking force at the apex of the passive membrane. For different driving voltages, stroke and force were measured with a double-column dynamometer (Z005, Zwick Roell, Germany) according to the procedure described in Carpi et al. (2011b). In particular, a cylindrical indenter was mounted on the mobile crossbar of the machine, attached to a load cell. The indenter had a diameter of 12 mm, so as to fit with the internal part of the plastic case of the device. The crossbar was then moved, until the load cell detected a contact between the indenter and the actuator’s passive membrane, as shown in Figure 4. Then the actuator was electrically driven, so as to cause a displacement of the membrane’s apex. After that, the tool was brought in contact again with the actuator. The distance covered to restore contact was considered as the active displacement (free stroke). Subsequently, the voltage was turned off, without changing the position of the tool. As a result of this, the relaxation undergone by the actuator while trying to recover its rest shape generated a force, whose steady-state final value was considered as the blocking force. Finally, the crossbar was brought back to the initial position, and the actuator was allowed to fully recover its original shape. The test was repeated for voltages up to 4.5 kV, which was used as a safe limit to avoid electrical breakdown.

Bottom Line: The device was based on dielectric elastomer actuators, as high-performance electromechanically active polymers.The actuator was arranged at the user's fingertip, integrated within a plastic case, which also hosted a compact high-voltage circuitry.We present the structure of the device and a characterization of it, in terms of electromechanical response and stress relaxation.

View Article: PubMed Central - PubMed

Affiliation: School of Engineering and Material Science, Queen Mary University of London , London , UK.

ABSTRACT
We describe here a wearable, wireless, compact, and lightweight tactile display, able to mechanically stimulate the fingertip of users, so as to simulate contact with soft bodies in virtual environments. The device was based on dielectric elastomer actuators, as high-performance electromechanically active polymers. The actuator was arranged at the user's fingertip, integrated within a plastic case, which also hosted a compact high-voltage circuitry. A custom-made wireless control unit was arranged on the forearm and connected to the display via low-voltage leads. We present the structure of the device and a characterization of it, in terms of electromechanical response and stress relaxation. Furthermore, we present results of a psychophysical test aimed at assessing the ability of the system to generate different levels of force that can be perceived by users.

No MeSH data available.


Related in: MedlinePlus