EP-4741812-A1 - METHOD AND SYSTEM FOR TESTING TRIBOELECTRIC MATERIALS

EP4741812A1EP 4741812 A1EP4741812 A1EP 4741812A1EP-4741812-A1

Abstract

A method and system for testing triboelectric materials comprising: a first platform (2); a counter-electrode (5) arranged on the first platform to receive a piece of a first triboelectric material; a force measurement means to measure force at the first platform; a piston (11); a second platform (12) at one end of the piston; an electrode (13) arranged at the second platform to receive a piece of a second triboelectric material; a drive system (15) to vertically move the piston to a position with contact between the two triboelectric materials at a certain level of force and frequency; and measuring means to measure an output signal as result of the contact between the triboelectric materials.

Inventors

MARTÍN-GONZÁLEZ, Marisol
GARCÍA COBOS, Carlos

Assignees

Consejo Superior de Investigaciones Cientificas

Dates

Publication Date: 20260513
Application Date: 20241112

Claims (15)

A system for testing triboelectric materials characterized by comprising: - a first platform (2); - a counter-electrode (5) arranged on the first platform (2), configured to receive a piece of a first triboelectric material; - a force measurement means configured to measure force at the first platform (2); - a piston (11); - a second platform (12) arranged at one end of the piston (11); - an electrode (13) arranged at the second platform (12), configured to receive a piece of a second triboelectric material; - a drive system (15) operatively associated to the piston (11), where the drive system is configured to vertically move the piston (11) from a first position without contact to a second position with contact between the piece of the first triboelectric material and the piece of the second triboelectric material at a certain level of force and frequency; and - measuring means, electrically connected to both the electrode (13) and the counter-electrode (5), configured to measure an output signal as result of the contact between the piece of the first triboelectric material and the piece of the second triboelectric material.
The system of claim 1 further comprising a control module, connected to the drive system, configured to set the certain level of force and frequency to be applied by the piston.
The system of claim 2 wherein the measuring means further comprise a plurality of relays arranged in parallel, being each relay connected to a different resistor; wherein the control module is further configured to activate one relay from the plurality of relays to let the output signal pass through a selected resistor.
The system of any one of claims 2-3 wherein the measuring means further comprise a rectifier-capacitor board, configured to convert the output signal into a direct current signal.
The system of any one of previous claims wherein the measuring means comprises a Keithley electrometer configured to measure the output signal.
The system of any one of previous claims further comprising a glass plate arranged on the first and the second platform.
The system of claim 6 further comprising a portion of double-side tape arranged on the glass plate of any one of the first and second platform, configured to hold the counter-electrode or the electrode, respectively.
The system of claim 7 further comprising a portion of double-side copper tape arranged on any one of the counter electrode and the electrode, configured to hold the piece of first triboelectric material or the piece of the second triboelectric material, respectively.
The system of any one of previous claims wherein the force measurement means are a pressure sensor arranged on the first platform.
The system of any one of previous claims wherein the piece of the first triboelectric material is a film of polytetrafluoroethylene.
A method for testing triboelectric materials characterized by comprising the following steps: - assembling a piece of a first triboelectric material on a counter-electrode (5) arranged on a first platform (2); - assembling a piece of a second triboelectric material on an electrode (13) arranged at a second platform (12), where the second platform is arranged at the end of a piston (11); - vertically moving the piston (11), by a drive system, from a first position without contact to a second position with contact between the piece of the first triboelectric material and the piece of the second triboelectric material at a certain level of force and frequency; and - measuring, by measuring means, an output signal as result of the contact between the piece of the first triboelectric material and the piece of the second triboelectric material.
The method of claim 11 wherein moving the piston a certain level of force and frequency comprises: - setting, by a control module connected to the drive system, the certain level of force and frequency to be applied by the piston; - measuring, by force measurement means, the force at the first platform during contact between the piece of the first triboelectric material and the piece of the second triboelectric material; - receiving, by the control module, force measures from the force measurement means; - determining, by the control module, a movement upwards of the piston to the first position based on the certain level of force set; and - determining, by the control module, a movement downwards of the piston to the second position based on the certain frequency set.
The method of any one of claims 11-12 wherein measuring an output signal further comprises: - connecting both the electrode and the counter-electrode to a resistor box having a plurality of relays arranged in parallel, being each relay connected to a different resistor; - activating, by the control module, one relay from the plurality of relays to let the output signal pass through a selected resistor; - connecting the resistor box to an electrometer; and - determining, by processing means connected to the electrometer, at least one voltage and charge measurement based on the output signal of the electrometer.
The method of any one of claims 11-12 wherein measuring an output signal further comprises: - connecting the electrode to a resistor box having a plurality of relays arranged in parallel, being each relay connected to a different resistor; - activating, by the control module, one relay from the plurality of relays to let the output signal pass through a selected resistor; - connecting the resistor box to an electrometer; - connecting the counter electrode to the electrometer; and - determining, by processing means connected to the electrometer, at least one current measurement based on the output signal of the electrometer.
The method of any one of claims 11-12 wherein measuring an output signal further comprises: - connecting both the electrode and the counter-electrode to a rectifier-capacitor board; - converting, by the rectifier-capacitor board, an alternating current generated at the electrodes to a direct current; - connecting the rectifier-capacitor board to an electrometer; and - determining, by processing means connected to the electrometer, at least one charge measurement of the capacitor based on the output signal of the electrometer.

Description

OBJECT OF THE INVENTION The object of the present invention refers to a method and system for testing triboelectric elements and more specifically to obtain voltage, charge and current measurements generated by a piece of material with triboelectric properties in a controlled way. BACKGROUND OF THE INVENTION The triboelectric effect is a contact induced electrification in which a material becomes electrically charged after it is contacted with a different material through friction or touching, so a triboelectric nanogenerator (TENG) generates an electric field from the mechanical energy. Nowadays, triboelectric nanogenerators are earning interest in electrical industry, especially in energy harvesting and self-powered systems. For example, TENGs can be integrated into clothing, shoes, or accessories to harvest energy from human motion and power wearable devices. Autonomous Sensors as forest fire detectors, dust and particle sensors, and LED power supplies may also benefit from triboelectric material, as well as "Smart Clothing" may embed TENG based sensors in order to measure vital signs and monitor physical exercise. On the other hand, the strong development of loT devices and their low energy requirements may rely on triboelectric generators as they provide costeffective and eco-friendly energy harvesting technology. In summary, materials with triboelectric properties offer versatile applications, from powering wearables to monitoring environmental conditions, and they continue to evolve toward a more sustainable and connected future. However, the specific performance of every material and every structure of a same material is uncertain until a full triboelectric nanogenerator is built and start operating. The state of the art often resort to rough estimations provided for similar application of the same material stored in databases, so the performance forecast of any change in the structure of the material cannot be accurate. Therefore, the state of the art is missing accurate methods and systems for testing different materials and structures with triboelectric properties. DESCRIPTION OF THE INVENTION In order to achieve the objectives and avoid the drawbacks mentioned in previous section, a first aspect of present invention refers to a system for testing triboelectric materials comprising: a first platform;a counter-electrode arranged on the first platform, configured to receive a piece of a first triboelectric material;a force measurement means configured to measure force at the first platform;a piston;a second platform arranged at one end of the piston;an electrode arranged at the second platform, configured to receive a piece of a second triboelectric material;a drive system operatively associated to the piston, where the drive system is configured to vertically move the piston from a first position without contact to a second position with contact between the piece of the first triboelectric material and the piece of the second triboelectric material at a certain level of force and frequency; andmeasuring means electrically connected to both the electrode and the counter-electrode configured to measure an output signal as result of the contact between the piece of the first triboelectric material and the piece of the second triboelectric material. In one embodiment of the invention, it is further considered a control module, connected to the drive system, configured to set the certain level of force and frequency to be applied by the piston. According to one embodiment of the invention, the measuring means further comprise a plurality of relays arranged in parallel, being each relay connected to a different resistor; wherein the control module is further configured to activate one relay from the plurality of relays to let the output signal pass through a selected resistor. Thus, advantageously, present invention may filter noise of the output signal by selecting one of the resistors. In one specific embodiment of the invention, the measuring means further comprise a rectifier-capacitor board, configured to convert the output signal into a direct current signal. In one embodiment of the invention, the measuring means comprise a Keithley electrometer configured to measure the output signal. In one embodiment of the invention, it is further comprised a glass plate arranged on the first and the second platform. Additionally, according to one specific embodiment, present invention further comprises a portion of double-side tape arranged on the glass plate of any one of the first and second platform, configured to hold the counter-electrode or the electrode, respectively. Additionally, according to one specific embodiment, present invention further comprises a portion of double-side copper tape arranged on any one of the counter electrode and the electrode, configured to hold the piece of first triboelectric material or the piece of the second triboelectric material, respectively. According to one specifi