Wearable, energy independent platform for registration of wearer's and ambient data
Description of the Technology
In the proposed technological solution, the energy required to operate the system is derived using energy conversion modules (1, 10, Fig. 1) from the energy of human motion or / and the heat flow of the wearer's body, thereby making the system function independent of external energy sources. The basic components of the motion energy conversion module (1, Fig. 1) are one or more interconnected planar inductive elements created in the shape of helical structures and one or more magnets. The number of inductive elements and magnets is not fixed; it depends on the amount of space available in the garment. The motion of the magnets along the flat inductive elements produces a time-varying magnetic field flux, which in turn induces electro-motive force in them, in the case of a closed circuit, an electric current. The motion energy conversion module (1, Fig. 1) generates alternating current, which is rectified using the rectifier module (2, Fig. 1). The energy storage intermediate module (3, Fig. 1) performs a voltage fluctuation smoothing function and accumulates an electrical charge with the aim of reaching a voltage level which enables the low DC boost module (4, Fig. 1) to start. Body heat flux energy is converted into electrical energy using a heat flux energy converter (10, Fig. 1) based on the Zebeck / Peltier effects, converting the heat flux due to temperature difference between the its sides into electrical energy. The energy converted in this way is obtained in direct current mode, thus eliminating the need for a rectifier module. The DC voltage obtained in both ways is relatively low and is thus raised by the low DC voltage boost module (4, Fig. 1), which raises the voltage and transfers the stored energy to the main energy storage module (5, 1), which serve as power supply for the system control (7, Fig. 1) and data transmission (6, Fig. 1) modules. In order to provide energy flow during movement and at rest, by that increasing the system's operational sustainability and stability, the developed system is supplemented with thermal energy by combining the motion energy conversion module (1, Fig. 1) with the heat flow conversion module (10 , Figure 1).When the system is running, the stored energy increases the voltage in the main power storage module which is controlled through regular measurements, system functions are activated upon sufficient stored energy in the following order: system control module initialization, data transmitter initialization, data measurement and data transmission. As soon as a sufficient voltage level is reached in the main storage module, the metering function is activated and the system control module begins monitoring the stored energy to determine when it will be sufficient to start the specific metering function execution and data transmission. When the voltage and accumulated power level required to initialize the data transmission module is reached, the power is turned on, and then, when the required level is reached, the data measurement and transmission to the remote receiver is initiated. The operation of the entire system can be observed by recording the voltage on the main storage module, the change of which indicates energy storage and its use for measuring and sending data to the remote receiver (Fig.2).
During operation of the human motion energy converter, energy is stored up to the level corresponding to point A in Fig. 2, which corresponds to the time at which the system control module (7, Fig. 1) is initialized; as the voltage increases, the transmitter is initialized (point B, Fig. 2), followed by initialization of the measuring function (point C, Fig. 2), measurement itself (D, Fig. 2) and data transmission (point E, Fig. 2).
Applications
Possible applications for such a technology solution (system) are: 1. Remotely monitoring the health status of employees of different professions when the employee is performing professional tasks in the same clothes for a long time: soldiers, police officers, rescuers, firefighters, etc.; 2. A sport where it would in many cases be valuable to make similar observations remotely and directly during different activities; 3. Monitoring the health of infants and young children and determining their physical condition during sleep and various activities; 4. Remote monitoring of patient condition.
Advantages
Compared to existing electronic systems operated by a variety of single and rechargeable energy sources, an energy-independent system that communicates with a remote receiver by sending data over a wireless network allows for the creation of a hermetically closed module that will not require maintenance like replacing or charging batteries – i.e. no need to leave connection outputs.
In the case of wearable systems, this means that its operation will not be endangered by various adverse environmental conditions, such as rain and sweat, which dampen clothing and, in the case of non-hermetic systems, may cause short circuits and subsequent malfunctions.
The technology to be developed does not require direct input, such as in the case of piezoelectric elements, or the movement of one element through or inside the other, as in the classical electromagnetic converter. The transformation of the electrical power of movements takes place by moving individual magnets along flat inductive elements, i.e. these components of the converter can be integrated into clothing elements moving parallel to each other, as is the case for many clothing elements. Due to the flat design of the components, the integration of these elements into the garment elements practically does not alter the functionality and appearance of the garment.
Using and storing the energy of human motion and heat flow as electricity needed to run systems lowers adverse environmental impact by eliminating the use of disposable batteries and limiting use of rechargeable ones, mainly replacing them by capacitors that do not contain the heavy and harmful chemical elements, which, after the end of use, must be processed and recycled. Such wearable energy-independent systems are completely safe for users by storing small amounts (below 1 J) of energy, without long-term storage — energy is shortly used for measurement and data transmission, and power consumption is in range of milliwatts for the most.
Keywords
smart clothing,wearable electronics,energy harvesting