Patent Application
20240324713
The present disclosure relates to method of operating data-processing system for monitoring and maintaining the desired temperature inside a footwear. The said disclosure belongs to the technical field of thermoregulation circuits or devices with energy harvesting ability. More particularly, the disclosed data-processing system enables the footwear, that are equipped with electrical or electronic systems for cooling/heating, to further execute the energy harvesting from a body-footwear-surrounding temperature difference. Optionally, the footwear is equipped with an additional inductive energy harvesting device situated within the footwear to prolong a battery cycle.
Heating or cooling body parts is the most challenging problem encountered in smart-garment or smart-footwear field. All other activities in the said fields, oriented toward the data collection, transmission, various bio-parameter measuring, treating/acting with magnetic or electric filed, illuminating, etc. require substantially lower energy resources, even up to two orders of magnitude. Heating and cooling of the body parts therefore present a challenging problem that requires up to 100 Wats for proper functioning in extreme conditions, i.e., in harsh weather or other conditions.
Namely, a resting human body, without any activity, gives 100-120 Watts of energy, where only a small fraction can be used by a thermoelectric device to power wearable devices, see reference 1):
A 100 Watts target, that is 0.1 kWh requires a substantial power to be stored in battery pack that implies a significant weight to be carried. The most advanced cellular phone battery is emptied in less than 10 minutes with such power load, which implies that energy harvesting should be incorporated somehow in the energy-scheme to prolong full functionality of a smart footwear.
The main technical problem solved with the present disclosure is the formation of smart heating/cooling circuitry, together with the energy harvesting abilities, suitable to be used with a footwear. The above is achieved by using Peltier modules for heating/cooling and energy harvesting at the same time, with carefully selected duty cycles for each Peltier module.
The present disclosure addresses few other technical problems, such as additional wireless/inductive charging via carpet-like chargers that prolong the battery life as well, the artificial intelligence (AI) unit that is used to improve footwear's thermograph of heating/cooling abilities, etc.
In yet another embodiment, the heating/cooling meta-data is used for diagnostic properties, more particularly for signaling potential user's diabetes mellitus.
The state of the art has plethora of documents defining the art in general, such as reference 2) and 3) cited below:
The above article reveals that body heat harvesting systems, based on thermoelectric generators (TEGs), can play a significant role in wearable electronics intended for continuous, long-term health monitoring. In addition, the said article mentions that the harvested power density from the body using TEGs is limited to a few micro-watts per square centimeter, which is not sufficient for direct powering of the wearable devices.
Reference 3 demonstrates how off-the-shelf TEG/Peltier modules, with only 5% harvest efficiency, are possible to use for generating enough energy to power small devices using the body heat only.
Reference 4 teaches about the socks with cooling and heating abilities. In addition, with the said invention, the temperature of the human body part, i.e., the foot, is maintained at an appropriate temperature which is especially suitable in cases of various diseases, such as frostbite, athlete's foot, eczema, and heat rash. This document remains silent regarding the possible energy harvesting and corresponding controlling of used TEG modules.
Reference 5 discloses an insole that is capable to be cooled and heated with the Peltier module. The document is silent regarding the possible energy harvesting feature.
Reference 6 discloses a power generation apparatus using a temperature difference between the inside and the outside of a garment, and more particularly, to a power generation apparatus provided in a garment to produce electric power by using a temperature difference between a body temperature inside the clothes and an environment outside the clothes. The document is silent regarding the possible heating/cooling having in mind that is focused solely to the energy harvesting.
Reference 7, and cited references therein, discloses power-management circuitry for thermoelectric energy harvesting. Said reference describes a low input voltage step-up converter, constructed from readily available components, able to boost the output voltage of a thermoelectric generator (TEG) energy harvester to a usable level.
Reference 8 discloses pulsed width modulation (PWM) temperature controller used in controlling a garment temperature, e.g., for active heating of an underwear. The present reference remains silent regarding any harvesting or switching other heating/cooling modules with same or different PWMs.
The above selected documents are cited according to the best inventors' knowledge.
Present disclosure relates to a novel method of operating data-processing system for monitoring and maintaining desired temperature inside the footwear, by using a smart device which is operated by a user. According to the preferred embodiment, the said footwear is equipped with:
Said one or more outer temperature sensors are connected via a data cable or via a wireless connection with the data processing unit for sending measured outer temperatures data To to the data processing unit.
The disclosed method is defined via the following steps:
In step E. and step F. the value for the index i is changed consecutively to be 1->2->3-> . . . ->(N−1)->N with a time period D that defines a duty cycle of each i-th Peltier module. During step E. and F. all N used Peltier modules are time multiplexed in a manner that only one Peltier module is active at a particular time instance. An adjustable time period D1 is inserted before starting each new cycle 1->2->3-> . . . ->(N−1)->N during which the data processing unit sets all Q1, Q2, . . . , QN switches to direct generated currents from the energy harvesting processes from the temperature difference between the inner and outer footwear temperature towards the power management unit. Time periods D and D1 are used to regulate delivered power for heating/cooling regime and to bring the average temperature <Ti> within the set range [TLo, THi]. The method steps A., B. and C. are independently executed to provide the most recent data about the temperatures, for continuously executing loop defined by steps D.->E.->F.->D.
In an alternative embodiment, in steps E. and F. additional time period D2 is inserted between each switching from i-th to (i+1)-th Peltier module. Said time period D2 is again used in the process of power regulation together with time periods D1 and D, where during the said period D2 all Peltier modules are used for harvesting energy from the temperature difference between the inner and outer footwear temperature and the data processing unit sets all Q1, Q2, . . . QN switches to direct generated current towards the power management unit.
In yet another embodiment, time period D for each i-th Peltier module is adjustable and depends on a used Peltier module position and the inner sensor temperature that is most closely situated to the said i-th Peltier module.
A footwear, with the above said characteristic, that is capable to perform method of operating data-processing system defined above is also disclosed. In preferred embodiment, said footwear is a smart sock.
In one variant, the charging of the said footwear is performed via an inductive charger formed as the carpet or similar 2D device. In a yet another variant, one or more outer temperature sensors are connected via the data cable with the data processing unit or, said one or more outer temperature sensor are connected via the wireless low energy module with the data processing unit.
In yet another variant, a meta-data of the conducted method of operation, occurred in the data processing unit, are transmitted via the smart device to the cloud, together with the accompanied smart device data.
In yet another variant, an artificial intelligence unit is used to improve footwear's thermograph of heating/cooling abilities, based on transmitted meta-data.
In yet another variant, the doctor or other authorized data scientist can access the meta-data in order to establish biological circles and patient's behavior, especially when combined with the smart device data.
In yet another variant, the doctor or other authorized data scientist can access the meta-data for an artificial intelligence unit supported diagnostic, especially for signaling potential user's diabetes mellitus disease.
The present disclosure relates to method of operating data-processing system for monitoring and maintaining the desired temperature inside a footwear. In the first part, the footwear according to the invention is described in detail.
In the preferred embodiment, the used footwear can be formed as a shoe, a sock, or any other suitable footwear capable to enclose the entire foot, preferably in a manner of a textile or leather barrier to the surrounding environment. Such footwear is depicted on
Each footwear (100) is equipped with a data processing unit (70) for executing the below described method. Data processing unit (70) may be any of the shelf microcontroller module capable to collect footwear's inner and outer temperature data, to controls switch S1 that regulates working regime, i.e., heating/cooling, and where the said data processing unit (70) additionally controls a driving module (71), whose function will be discussed later.
According to the preferred embodiment, a plurality of Peltier modules (10.i); i=1, 2, . . . , N, is distributed over the footwear (100) surface, more preferably close to the inner surface of the said footwear for improving heating/cooling and energy harvesting abilities. Preferably, the used Peltier modules are flexible one, such as those TEGs described in reference 9) below:
Used TEGway's flexible thermoelectric device has a ZT value (˜0.7) comparable to conventional rigid bulk type thermoelectric device, and yet provides better performance in real applications. The ZT value is defined as the dimensionless figure of merit, ZT=S2T/(ρκ), and it is calculated from the Seebeck coefficient (S), electrical resistivity (ρ), and thermal conductivity (κ), where T stands for absolute temperature, where all mentioned physical observables are temperature dependent, which is known in the art.
The person skilled in the art will immediately recognize advantages of the flexible thermoelectric devices over a rigid TEGs in formation of the footwear according to the said disclosure.
Each of said Peltier modules (10.i) is simultaneously used for heating/cooling function—in an active state, and for energy harvesting in its passive state, that will be explained in more detail in the section devoted to the method of operation. Furthermore, each Peltier module (10.i) is connected with the corresponding power cable (11.i) to the power busbar (40) connected to the driving module (71) and power management unit (91). Having in mind that all devices are built into the footwear, it is necessary to have power cables (11.i) formed from cables suitable for textile usage. Examples of such power or data cables are these disclosed in reference 10) below:
Said cables are entirely washable, able to be stitched, and therefore suitable to be used in smart socks or smart shoes formation.
In the preferred embodiment, one or more temperature sensors (20.j), j=1, 2, . . . , M; are distributed over the footwear (100) surface and connected with the corresponding data cables (21.j) to the sensors' busbar (50). Said sensors (20.j) are used for measuring inner temperature Ti for each sensor on location j, and are preferably uniformly distributed over the surface, and situated away the used Peltier modules (10.i) in order to eliminate false temperature readings. Considering the needed reading accuracy, any off-the-shelf point temperature sensor is suitable for the mentioned purpose, if it is able to communicate via the data-cable with the data processing unit (70).
A battery module (90), located preferably close to the ankle region of the said footwear, is equipped with the power management system (91) for powering the said Peltier modules (10.i) through the power busbar (40). Preferably, the flexible battery module (90), suitable for wearable technology is used. Again, the busbar is formed from the textile power cables disclosed in reference 10). The power management system is designed to fulfill several tasks, i.e., for charging the battery module (90) in the energy harvesting regime from one or more Peltier modules and for powering the data processing unit (70) and joint circuits that enable the said disclosure.
One of important and nontrivial joint circuit is a driving module (71). This module is designed for executing the data processing unit commands to switch between energy harvesting condition or heating/cooling condition for each Peltier module (10.i) via the set of corresponding switches [Q1, Q2, . . . Qi, . . . , QN], as depicted on
The footwear, according to the preferred embodiment, has a wireless low energy module (80) for establishing a communication with any smart device (300). In practice, the best choice seems to be Bluetooth Low Energy Module (BLE), due to its versatility and well-established standard. Any smart device (300), such as a mobile device, a smart watch, or similar device, is used to set low (TLo) and high (THi) operational temperature of the mentioned footwear and for controlling parameters of the said method of operation. In one variant, the said smart device (300) is optionally used to communicate with one or more outer temperature sensors (30.k); k=1, 2, . . . , P, via a wireless connection (51) and to transmit the outer temperature data (To), via the mentioned BLE module to the data processing unit (70). In yet another variant, the outer temperature sensors (30.k) are connected via the data cable (31) with the data processing unit (70), for measuring outer temperatures To.
One or more outer temperature sensors (30.k) are needed for proper functioning of the smart footwear. Said sensors can be located on the outer surface of the footwear, or, preferably away of the said footwear to minimize false reading due to the user's body heat emission. In the latter case, it is necessary to have the data cable (31) or the above cited wireless connection (51) to transmit the temperature data to the data processing unit (70).
In yet another variant of the disclosure, an inductive charging device (92) is designed to be connected with the power management system (91), and to enable additional contactless charging of the battery module (90) beside energy harvesting due to the temperature differences. Namely, most of the time, the dedicated users (200) are sitting at their working places resting their feet on the floor, or on specifically designed resting pads. The similar situation occurs at their homes, for instance during the television watching, when the wireless charging can be performed via smart carpet. The said resting pads or carpets or any other almost two-dimensional (2D) objects can be equipped with inductive charger to cooperate with the charging device (92), built into the said footwear. In that sense, such additional power supply will prolong the ability of the said smart footwear, i.e., the sock, to operate according to the desired needs.
The most challenging part in any heating/cooling of the footwear is its active surface that has to be thermalized. For the person skilled in the art, it is obvious that one Peltier module is not convenient for the mention use, and that more modules should be used. It is observed that the thermal diffusivity, which measures the heat transfer rate of a material from the hot end to the cold end, is significant in foot-footwear system. Therefore, it is convenient to switch one-by-one Peltier module on/off for cooling or heating purpose, which increases the thermalization time but lowers the net current used for powering the system and where such powering scheme preserves battery system. In addition, it is possible in that way to regulate the delivered or extracted heat power from the footwear by changing the duty cycles of the mentioned Peltier modules, in a manner that the duty cycle corresponds with the temperature difference between the desired temperature and actual inner footwear temperature.
The inventive part of the disclosure is that while i-th Peltier module is in its cooling/heating mode, all other Peltier modules are working as the energy harvesting devices and charges the battery module. The set duty cycle for the i-th Peltier module defines the period of activity for the i-th Peltier module.
The method steps are schematically depicted on
In step A., the system loading the user (200) pre-defined high temperature threshold THi, and low temperature threshold TLo, entered via the smart device (300) and transmitted via the wireless low energy module (80) into the data processing unit (70), see
THi and TLo define the operational range, for instance from 34° C. to 36° C., but any other convenient range can be set.
In step B., the data processing unit (70) loads the inner temperature sensors' set of values for j=1, 2, . . . M, [Ti1, Ti2, Ti3, . . . , TiM] and calculates the average inner temperature <Ti> from the said values.
In step C., the data processing unit (70) loads the outer temperature sensors' set of values for k=1, 2, . . . P, [To1, To2, To3, . . . , TiP] via the wireless low energy module (80) or directly via data cables, as explained earlier.
If temperature <Ti> is within the range [TLo, THi], then all Peltier modules (10.i), i=1, 2, . . . N are used for harvesting energy from the temperature difference between the inner and outer footwear temperature, as depicted on
If temperature <Ti> is below TLo, then the data processing unit (70) sets all Q1, Q2, . . . Q(i−1), Q(i+1), . . . QN switches for harvesting energy to direct generated current towards the power management unit (91), while the data processing unit (70) sets only Qi switch into heating/cooling condition for i-th Peltier unit (10.i) and additionally set S1 switch to heating. Said case is depicted for t>t2 on
If temperature <Ti> is above THi, then the data processing unit (70) sets all Q1, Q2, . . . Q(i−1), Q(i+1), . . . QN switches for harvesting energy to direct generated current towards the power management unit (91), while the data processing unit (70) sets Qi switch into heating/cooling condition for i-th Peltier unit (10.i) and additionally sets S1 switch to cooling. Said case is depicted for t<t1 on
Steps D., E., F. set the regime for i-th Peltier unit (10.i) and defines the working conditions for other Peltier units (10.j) where i≠j in case of steps E. and F.
In step E. and step F. the value for the index i is changed consecutively to be 1->2->3-> . . . ->(N−1)->N. This change has time period D that defines a duty cycle of each i-th Peltier module. Effectively, that defines the working or occupation time for the said Peltier module, as depicted on
The person skilled in the art will immediately recognize the ability to regulate delivered power for heating/cooling regime and to bring the average temperature <Ti> within the set range [TLo, THi] by adjusting D and D1 time periods. Longer D1 period means the lower total energy for heating/cooling is achieved in time. Longer D period means the higher total energy of some particular Peltier's unit for heating/cooling is delivered to the system foot-footwear. Similar power management is already disclosed in reference 8) cited before, however without ability to simultaneously harvest the energy from the temperature difference, where reference 8) is silent.
Finally, it is important to note that steps A., B. and C. are independently executed to provide the most recent data about the temperatures, while the steps D.->E.->F.->D. are executed in continuous loop.
In one variant of invention, depicted on
In yet another variant, it is possible to further improve the power regulation. Namely, the data processing device (70) can firstly read the j-th temperature sensor that is most closely situated to i-th Peltier module (10.i). Based on the said j-th temperature and the desired temperature range, i.e., THi and TLo, it is possible to adjust the time period D for the said Peltier module to achieve the best thermalization properties of the entire footwear. Hereby, as well in other variants, all other modules except the i-th are used for the energy harvesting.
The person skilled in the art may find other PWM forms to regulate heating/cooling power delivered to i-th Peltier module, while other modules j, where j/i, are turned to harvesting energy regime.
It is possible to use an artificial intelligence unit (400) to improve footwear's thermograph of heating/cooling abilities, based on the transmitted meta-data, by taking into account the current user locations-if necessary.
Also, the doctor (600) or other authorized data scientist can access the meta-data in order to establish biological circles and patient's behavior, especially when combined with other smart device (300) data.
Furthermore, it is possible to link the foot temperature with the possible health issues, as is demonstrated in the article below:
So, the recorded skin temperature can be effectively used for an artificial intelligence unit (400) supported diagnostic, especially for signaling potential user's diabetes mellitus disease.
Therefore, the signaling regarding the potential diseases are possible, more specifically, the diseases linked with abnormal foot skin temperature.
Industrial applicability for the said disclosure is obvious. The present disclosure relates to method of operating data-processing system for monitoring and maintaining the desired temperature inside a footwear which is improved by energy harvesting regime via already used Peltier modules, beside well-known heating/cooling abilities.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/071230 | 7/28/2021 | WO |
