WO2020215141A1

WO2020215141A1 - Braille cell and braille communication device including the cell

Info

Publication number: WO2020215141A1
Application number: PCT/BR2020/050139
Authority: WO
Inventors: José ERICK DE SOUZA LIMA; Roberto LACERDA DE ORIO
Original assignee: Universidade Estadual De Campinas; Instituto Federal De Educação Ciência E Tecnologia De São Paulo - Ifsp
Priority date: 2019-04-25
Filing date: 2020-04-23
Publication date: 2020-10-29
Also published as: BR102019008354A2

Abstract

The present invention pertains to the fields of mechanical and electrical engineering, and more specifically to assistance devices for people who are visually impaired. Accordingly, the present invention provides a braille cell (1) comprising: pins (11); springs (12); and connecting wires with shape memory (13); positioning wires (14); control wires (15); and pulleys (16); in which the pins (11) fit into the springs (12), the positioning wires (14) link the pins (11) to the shape-memory wire (13) by means of the pulleys (16) and the control wires (15) are connected to the shape-memory wires (13); in which the shape-memory wires (13) are stretched and generate an initial load on the spring (12); in which the pulleys (16) are designed to transfer the horizontal linear movement of the shape-memory wires (13) vertically to the positioning wires (14), and in which the control wires (15) are designed to transmit a control signal to the shape-memory wires (13) so as to position the pins (11) in a desired position. The invention also provides a braille communication device including the described cell.

Description

BRAILLE CELL AND BRAILLE COMMUNICATION DEVICE

UNDERSTANDING THE CELL

FIELD OF THE INVENTION

[001] The present invention falls within the field of mechanical and electrical engineering, more specifically in assistive devices for people with visual impairments. Particularly applicable to people who have visual impairments and need equipment to facilitate their adaptation, including reading and learning in Braille. BACKGROUND OF THE INVENTION

[002] Visual impairment is a term that is associated with an irreversible state of decreased visual ability of an individual, caused by congenital (pathogenic) or environmental factors (pathologies, injuries, tumors, etc.).

[003] In Brazil alone, according to the "CENSUS CARTILHA 2010 - PERSONS WITH DISABILITIES", 18.6% of the population, that is, about 35,791,488 million people, declared to have some type of visual impairment. Of these, 1.6% of Brazilians are totally blind and 3.46% have severe visual impairment. Such deficiencies can occur in two ways: blindness or low vision.

[004] People with blindness are those who present from the total absence of vision to the loss of light projection, which makes their learning process happen through the other senses (touch, smell, hearing and taste). Those with low vision, on the other hand, are able to indicate light uptake to the degree that the reduction in visual acuity interferes or limits their performance. In both cases, the Braille System can be used as the main however, it needs to be adapted for use with mobile communication technologies such as smartphones, which have a large worldwide adhesion.

[010] Still, generally, the traditional Braille cells, found in reading equipment in Braille use piezoelectric materials, whose characteristic is to expand and contract when exposed to an electrical potential. Such an effect is called a "piezo effect".

[005] However, these cells have high construction complexity, since they are formed by several conditioning circuits, in addition to the complexity of use, since piezo materials are high cost raw materials, which raises the price of equipment reading Braille.

[006] Currently, shaped memory materials are being studied and analyzed for use in systems of this type, however they are devices without total control of the pins, as well as large solutions, which prevent them from being used for compact and mobile Braille readers. . TECHNICAL STATUS

[007] Some state-of-the-art documents describe devices aimed at meeting the needs described, as highlighted below.

[008] North American document US 2011/0269106 AI describes an actuation mechanism for Braille displays, which includes including a body, compression springs, sliding blocks, pins and an alloy wire with shape memory. As described, the sliding block is activated by the interaction between the compression spring and the shape memory alloy wire. The alloy wire with shape memory, for in turn, it is activated by the current of a power supply in a modulated or unmodulated way. However, it is clear from what is described in the document that the pins are dependent on the force of gravity to return to their original position (lower), thus leaving the pin loose in the absence of power, being able to change position if the device moves, ie , the described technology does not provide the pin control with the precision necessary for a portable device, which can lead to inaccuracy of the reading. Furthermore, its relatively large size, in addition to the pin being rigid on a solid surface, is not comfortable for a user.

[009] Another document that can be cited is the Patent Application for the Patent Cooperation Treaty (PCT) WO 2013/179311 Al, which describes a system for generating an updatable touch display, including Braille characters and planar graphics. The device comprises a plurality of electronic units, a cooling unit and a filter. The electronic unit comprises a plurality of points in Braille, a plurality of tactile elements, an element of upper structure, a wrapper of wires and an element of lower structure. Each of the tactile elements includes an alloy wire with shape memory, crimp terminals at both ends of said wire and a pair of concentric parallel compression springs. Thus, the technology described uses shape memory alloy to selectively design and retain Braille dots, for use in modular tactile displays of several lines of characters that form the main tactile output devices. In addition to such a display maintaining the document previously mentioned, such display still uses double wires, double moías, and the shape memory wire is stretched entirely in the vertical position, making the device very high, making it impossible for the solution to be used for compact and mobile Braille readers.

[010] Still, the North American document US 9142105 BI and the Chinese document CN 105103216 A describe updatable tactile displays that perform a horizontal movement to move the pins vertically, however, as can be seen in the documents, such a structure is complex and clearly great for the solution to be used for compact and mobile online Braille readers. Again, several of the problems mentioned above are still present in such documents.

[011] Thus, it is clear from the documents cited that no state-of-the-art device provides a compact, mobile, simple, lightweight and robust Braille device, which can thus be adapted for use with mobile communication technologies such as smartphones.

[012] Such problems were solved by the present invention, whose reduced format was designed to adapt to mobile devices such as smartphones, smartwatches, tablets, among others, facilitating the adaptation of visually impaired people.

BRIEF DESCRIPTION OF THE PRESENT INVENTION

[013] The present invention relates to a Braille cell, comprising: pins; springs; and alloy wires with shape memory; positioning wires; control wires; and pulleys; where the pins fit into the springs, the wires positioning links connect the pins to the memory wire by way of the pulleys, and the control wires are connected to the memory wires by shape; wherein the memory threads are stretched and generate an initial load on the spring; wherein the pulleys are configured to transfer the horizontal linear movement of the memory wires vertically in the positioning wires; and where the control wires are configured to transmit a control signal to the memory wires so as to position the pins in a desired position according to the force applied by the springs, the shape wires and the wires positioning.

[014] In a preferred configuration, the shape memory wire is a nitinol wire, and the shape memory wire can also be the positioning wire, or the positioning wire can be a nylon wire. The pulleys can also be micro pulleys.

[015] There is also a device for communication in Braille, which comprises a Braille cell as defined above, a structure for positioning said Braille cell, fixing elements, thermal insulation elements and control unit.

[016] In a preferred configuration, the fasteners are configured to adjust the initial load of the memory wire stretched over the spring, and the thermal insulation elements are positioned at the ends of the device for Braille communication and configured to isolate the parts thermally. A control unit responsible for triggering the device may consist of a control board comprising a microcontroller and a drive circuit composed of power drivers.

[017] Finally, in a specific configuration the device for communication in Braille comprises between 19.00 mm and 37.00 mm in height, 40.00 mm and 78.00 mm in length and 6.50 mm at 11.00 mm wide, and also comprise a microcontroller configured to generate a control signal transmitted by the control wires.

[018] Obviously, the device for communication in Braille can comprise a communication element, in which that communication element communicates with a mobile device, such a mobile device being a cell phone, smartphone, smartwatch or tablet.

BRIEF DESCRIPTION OF THE FIGURES

[019] The present invention will now be described below with reference to the typical embodiments of it and also with reference to the attached drawings, in which:

[020] Figure 1 is a representation of a front / side perspective view of a Braille cell, according to the present invention;

[021] Figure 2 is a representation of a front / right side perspective view of a structure for positioning a Braille cell, according to the present invention;

[022] Figure 3 is a representation of a front / right side perspective view of a device for communication in Braille using a Braille cell, according to the present invention;

[023] Figure 4 is a representation of a right side view in cross section of a communication device. in Braille using a Braille cell, according to the present invention;

[024] Figure 5 is a representation of a Braille cell compared to a user's finger, according to the present invention;

[025] Figure 6a is a representation of a perspective view of a Braille reading device including three Braille cells, in accordance with the present invention;

[026] Figure 6b is a representation of a perspective view of a Braille reading device including three Braille cells without the top cover, illustrating the internal elements, in accordance with the present invention;

[027] Figure 6c is a representation of a top view of a Braille reading device including three Braille cells without the top cover, illustrating the internal elements, in accordance with the present invention;

[028] Figure 6d is a representation of a top view of a Braille reading device including three Braille cells, in accordance with the present invention; and

[029] Figure 7 is a representation of a block diagram illustrating the Braille reading device and its communication with a mobile device, according to the present invention.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[030] As previously described, the present invention falls within the field of mechanical and electrical engineering, more specifically in assistive devices for people with visual impairments. Particularly applicable to people who are visually impaired and need equipment for facilitate their adaptation, including reading and learning in Braille.

[031] As can be seen in Figures 1 to 4, a Braille cell 1 is described, as well as a structure 2 for positioning the Braille cell 1 and a device for communication 3 in Braille that uses both the Braille cell

I, regarding the structure for its positioning.

[032] As can be seen in figure 1, a Braille 1 cell according to the present invention comprises pins

II, springs 12, alloy wires with shape memory 13, positioning wires 14, control wires 15, pulleys 16 and a cover 17.

[033] In each cell, the pins 11 fit into the compression springs 12, and the positioning wires 14 go from pin 11 to a connection with the shape 13 memory wire, preferably a nitinol wire, which are isolated between themselves for thermal reasons. The shape memory wire 13 is stretched and generates an initial load on the spring 12, adjusted by a fastener that will be described later. Control wires 15, preferably copper wires, are connected to the ends of the memory wires 13, and generate a control signal for the memory wires 13, positioning the pins 11 in the desired position.

[034] In this way, at one end there is a cell, preferably composed of six pins, which will form the character in Braille. At the other end is the power supply, controlled, for example, by a microcontroller, responsible for increasing the temperature in order to activate the memory wires 13.

[035] Springs 12 generate a tactile force, and the return of pins 11 that are inserted at the top of the cell. Thus, the moías 12 are fundamental for two functions: the return of the pin 11 and the tactile resistance to the touch, which forms the character in Braille.

[036] In addition, the electromechanical Braille 1 cell comprises pulleys 16, preferably micro pulleys, which can have from 0.7 mm to 1.75 mm in diameter and a length compatible with the width of the set of Braille cells, being positioned in holes compatible passers in the vertical base of the Braille cell, and are configured to transfer linear movement from horizontal to vertical.

[037] When heated via electric current, the memory wire contracts (usually from 2% to 5% of its original dimension), increasing the mechanical tension and compressing the spring 12. In this way, pin 11 makes a movement linear down and the sheave 16 transfers the force from the x axis to the y axis. When the electrical current is terminated, the memory wire 13 cools, the spring 12 overcomes the established voltage and pushes pin 11 linearly upwards.

[038] It should be noted that the positioning wire 14 can be replaced by a copper conductor with two holes, for example. This modification can prevent the high temperature from coming into contact with the plastic material of the positioning wire. In this configuration, the shape memory wire runs from pin 11 to the base, and is energized through contact with the copper conductor, that is, the shape memory wire itself can be the positioning wire 14.

[039] As can be seen in figures 2 to 4, such a Braille cell 1 can be used in a structure 2 for positioning, as well as in a device for communication 3 in Braille.

[040] In a particular configuration, the Braille communication device 3 comprises a structure 2 that houses three Braille cells 1 as described above, as well as fastening elements 31, which as previously described adjusts the initial load of the wire shape memory

13 stretched over the spring 12, and thermal insulation elements 32, preferably copper plates, positioned at the ends of the device and configured to thermally insulate the parts.

[041] In a specific construction example, described here in a non-limiting way only for the sufficient description of the invention, springs 12 of 5.0 mm were mounted on plastic pins 11, together with a positioning wire

14 nylon, 0.20 mm in diameter.

[042] To pull pin 11 and compress the spring 12 by about 0.8 mm, a nitinol-shaped memory wire, with a diameter ranging from 0.0762 to 0.13 mm, with an activation temperature of approximately 90 ° C. In this case, the wire activation speed at the activation temperature varies between 0.5 s and 1.0 s. The cooling (return of the pin) occurs with speed between 0.5 s and 1.4 s.

[043] The control unit comprises a drive circuit 73 composed of power drivers for driving the SMA, receiving PWM signals programmed in the microcontroller contained in the control board 71 to prevent overheating and damage to materials. Using a 5V source as input, the PWM pulses generate higher average current signals in the first tenths of a second with a higher duty cycle (DT), falling 40% compared to the duty cycle thus decreasing the average current, but keeping the nitinol wire tensioned.

[044] The pins 11 fit into the compression springs 12, the nylon threads go from pin 11 to a connection with the nitinol wire, which are isolated from each other for thermal reasons. The nitinol wire is stretched and generates an initial load on the spring, adjusted and fixed to the base of the phenolite plate by an electrical connection method, and a pressure terminal, glue, welding, screw, or any other fixation method can be used.

[045] As previously described, when heated via electric current, the NiTi wire contracts from 2% to 5% of its original dimension, increasing the mechanical tension and compressing the spring. In this way, the pin makes a linear downward movement and the micro pulley transfers the force from the x-axis to the y-axis. When the electric current is terminated, the nitinol wire cools, the spring overcomes the established voltage and pushes the pin linearly upwards. The initial average current ranges from 124 mA to 320 mA and, after tens of milliseconds, rests on an average current ranging from 100 mA to 250 mA by PWM pulses from the microcontroller. The nitinol wire used on each pin 11 has a diameter between 0.0762 mm and 0.13 mm, is driven at 90 ° C, measures from 30 mm to 55 mm, and presents a contraction of 1 mm to 2 mm.

[046] With such a configuration, it is possible to miniaturize the device itself, in which the cover 17 of the Braille cell 1 comprises a distance between the centers of the pins from 2.5 mm to 3.5 mm, and a height in the region of the pins 11 only 0.9 mm. The structure that comprises the three cells has between 19.00 mm and 37.00 mm high, 40.00 mm and 78.00 mm long, and 6.50 mm to 11.00 mm wide, that is, extremely compact, robust and simple. As can be seen in figure 5, such a cell is extremely minimized in relation to the state of the art, and is limited to the back of the user's finger.

[047] Obviously, such a device can be used in a Braille reader using the elements defined above.

[048] As can be seen in figures 6a to 6d, the device that forms the cell can be installed, for example, in a plastic box, with a smooth surface, designed with space for reading three characters. Braille cells can be screwed into the box and adjusted using the pin that plays the pulley as a guide. Figure 6a illustrates a Braille reading device in this sense, complete and closed, while Figure 6b illustrates the same device without the cover, illustrating the three correctly positioned Braille cells as shown above.

[049] As can be seen in figure 6c, for cooling, an exhaust fan can be positioned in the direction of the hollow parts of the Braille cells, where the nitinol wires are, aligned with holes on the opposite side of the box, causing the air external enter the box on one side and the heat exit on the other side, passing strategically between the hollow parts of the Braille cell, cooling the nitinol and consequently reducing the cooling time and activation of the pin, thus producing a continuous air flow. To start nitinol more quickly, overcurrent can be used at the beginning and then decrease the current average via PWM to maintain pin position. The cooling system accelerates the return of the pin, when the current is removed. Finally, figure 6d shows a top view of the closed box. In this illustrative example, the complete box is 10 centimeters wide and 9 centimeters high. Obviously, such sizes are illustrative and not limiting, and demonstrate how it is possible to minimize not only the cells, but also the complete device.

[050] As can be seen in figure 7, the device comprises in its box a control unit comprising a control board 71, comprising a microcontroller, which drives the power drivers of the drive circuit 73 to correctly move the Braille cell 74. The microcontroller contained in the control board 71, in turn, can receive the information through a communication element 72, either by cables, wireless or Bluetooth. In a non-limiting example, a Bluetooth circuit is used, which in turn communicates with a mobile device 75 that already has such technology, thus facilitating the use of the device.

[051] For the activation of the equipment through the microcontroller present on the control board, specific software was developed, called SABr.LE. The program provides a sequence of tasks scheduled for the start of reading and writing in Braille, adding an electromechanical Braille device with wireless communication, aiming at a more accessible cost and portability for the visually impaired. Obviously, although the specific software is described, other control software can be developed, since the functioning of the cell is simplified as described above.

[052] The architecture of the device can consist of a control board 71 and the drive circuit 73. The control board has a microcontroller, which receives information from a data bus and, according to the information received from the device mobile, act on the drive circuit. The address bus defines which pins will be triggered to form the Braille character. Obviously, the microcontroller could be replaced by other processing units to activate the Braille device.

[053] On the mobile device, an application can be installed which, when started, establishes communication with the embedded system via Bluetooth, for example. An application was developed for the purpose of literacy, but the device developed is capable of operating with the reading function and can be designed with a higher number of characters.

[054] Thus, a SaBr.LE platform can be considered as a system composed of Braille 1 cells and the SABr.LE Software, developed to trigger them, which is installed as an application on the mobile device.

[055] Obviously, the device for reading in Braille can be designed with the number of characters that is convenient according to its application, be it literacy or reading in general. The device when comprising Bluetooth communication can be operated with any mobile devices. Thus the device has application in teaching or as equipment for personal use for the visually impaired. [056] The Sabr.LE platform was developed with a specific application aimed at literacy in Braille, and can be adapted for other reading / writing tasks in Braille, and the Sabr.LE platform, composed of the Braille device and the access application, it is a very complete solution, aimed not only at the audience that already dominates the Braille system, but also at those who are learning to read and write.

[057] In view of the above, the present invention relates to a Braille 1 cell, comprising: pins 11; springs 12; and alloy wires with shape memory 13; positioning wires 14; control wires 15; and pulleys 16; wherein the pins 11 engage the springs 12, the positioning wires 14 connect the pins 11 to the shape wire 13 by means of the pulleys 16, and the control wires 15 are connected to the shape wires 13; wherein the memory wires of form 13 are stretched and generate an initial load on the spring 12; wherein the pulleys 16 are configured to transfer the horizontal linear movement of the memory wires 13 vertically in the positioning wires 14; and where the control wires 15 are configured to transmit a control signal to the memory wires 13 in order to position the pins 11 in a desired position according to the force applied by the springs 12, the memory wires of shape 13 and the positioning wires 14.

[058] In a preferred configuration, shape 13 memory wire is a nitinol wire, and shape 13 memory wire can also be positioning wire 14, or positioning wire 14 can be nylon wire . Still the pulleys 16 can be micro pulleys.

[059] A device for communication 3 in Braille is also provided, comprising a Braille cell 1 as defined above, a structure 2 for positioning said Braille cell 1, fixing elements 31, thermal insulation elements 32, and control unit consisting of a control board 71 and a drive circuit 73.

[060] In a preferred configuration, the fasteners 31 are configured to adjust the initial load of the memory wire so that it is stretched over the spring 12, and the thermal insulating elements 32 are positioned at the ends of the device for communication 3 in Braille and configured to thermally insulate the pieces.

[061] In a specific configuration the device for communication 3 in Braille comprises between 19.00 mm and 37.00 mm in height, 40.00 mm and 78.00 mm in length and 6.50 mm to 11.00 mm in width, and the control board comprises a microcontroller configured to generate a control signal transmitted by the control wires 15.

[062] Finally, the device for communication in Braille can comprise a communication element, in which that communication element communicates with a mobile device, such a mobile device being a cell phone, smartphone, smartwatch or tablet.

ADVANTAGES AND MODIFICATIONS

[063] In this way, the present invention solves the problems of the previous techniques by presenting a Braille 1 cell, of reduced and simplified format, in addition to a device for communication 3 in Braille that adapts to mobile devices such as cell phones, smartphones, smartwatches, tablets, among others, facilitating the adaptation of visually impaired people.

[064] However, such Braille 1 cells can be used in several types of devices that allow reading in Braille through pins 11 that form the characters. These cells are an alternative to traditional piezo cells, have a simpler physical structure and reduced cost.

[065] The developed technology also has activation via mobile devices, with Perkins virtual keyboard programs for Braille writing, which facilitates access since the disabled user does not need to adapt to a computing device, in addition to making the solution quite accessible to the public already familiar with the technology of smartphones and tablets.

[066] Although the invention has been widely described, it is obvious to those skilled in the art that various changes and modifications can be made without the said changes not being covered by the scope of the invention.

Claims

RE IVICATIONS

1. Braille cell (1), comprising:

pins (11);

moias (12); and

alloy wires with shape memory (13);

the Braille cell (1) characterized by also comprising:

positioning wires (14);

control wires (15); and

pulleys (16);

where the pins (11) fit into the springs (12), the positioning wires (14) connect the pins (11) to the shape memory wire (13) via the pulleys (16), and the control wires (15) are connected to the memory wires in a way (13);

wherein the shape memory wires (13) are stretched and generate an initial load on the spring (12);

wherein the pulleys (16) are configured in such a way as to transfer the horizontal linear movement of the memory threads (13) vertically into the positioning threads (14); and

wherein the control wires (15) are configured to transmit a control signal to the shape wires (13) in order to position the pins (11) in a desired position according to the force applied by the springs (12 ), the shape memory wires (13) and the positioning wires (14).

2. Braille cell (1) according to claim 1, characterized in that the shape memory wire (13) is a nitinol wire.

3. Braille cell (1) according to claim 1 or 2, characterized in that the shape memory wire (13) is also the positioning wire (14).

4. Braille cell (1) according to claim 1 or 2, characterized in that the positioning wire (14) is nylon.

Braille cell (1) according to any one of claims 1 to 4, characterized in that the pulleys (16) are micro pulleys.

6. Device for communication (3) in Braille, characterized in that it comprises a Braille cell (1) as defined in any one of claims 1 to 5, a structure (2) for positioning said Braille cell (1), fastening elements ( 31), thermal insulation elements (32) and control unit.

7. Braille communication device (3) according to claim 6, characterized in that the fixing elements (31) are configured to adjust the initial load of the memory wire in a way (13) stretched over the spring (12) .

8. Braille communication device (3) according to claim 6 or 7, characterized in that the thermal insulation elements (32) are positioned at the ends of the Braille communication device (3) and configured to thermally insulate the pieces .

9. Braille communication device (3) according to any one of claims 6 to 8, characterized in that it comprises between 19.00 mm and 37.00 mm in height, 43.00 mm and 78.00 mm in length and 6.50 mm a

11.00 mm wide.

10. Braille communication device (3) according to claim 6, characterized in that the control unit comprises a control plate (71) and a drive circuit (73).

11. Braille communication device (3) according to any of claims 6 and 10, characterized in that the control board (71) comprises a microcontroller configured to generate a control signal transmitted by the control wires (15 ).

12. Braille communication device (3) according to any one of claims 6 to 11, characterized in that it also comprises a communication element.

13. Braille communication device (3) according to claim 12, characterized in that the communication element communicates with a mobile device.

14. Braille communication device (3) according to claim 13, characterized in that the mobile device is a cell phone, smartphone, smartwatch or tablet.