Blind person intelligent indoor navigation and tumble alarm system based on ultra wide band positioning and posture detection

Abstract

The invention discloses a blind person intelligent indoor navigation and tumble alarm system based on ultra wide band positioning and posture detection. The blind person intelligent indoor navigation and tumble alarm system comprises an ultra wide band positioning module, a wireless communication module and an alarm module, the position information of the blind person is accurately tracked and positioned through ultra wide band equipment arranged on clothes of the blind person, a tactile stick and an indoor environment. By means of an advancing path danger judgment mechanism built in the tactile stick, the system can provide instant and visual warning for the blind according to the danger level, and therefore intelligent navigation assistance of the indoor environment is effectively achieved. Meanwhile, a posture detection algorithm is used, the posture of the blind person is monitored through three-axis acceleration and gyroscope data, and it is ensured that once the blind person falls down, the system can give an alarm and inform family members. Compared with the prior art, the method effectively solves the ubiquitous problems of high cost, insufficient precision, large size, potential privacy leakage and the like in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-wideband positioning, and in particular to an intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection. Background Art

[0002] China is currently the country with the largest number of blind people in the world, but there are many problems with guide aids. The first is that guide aids are expensive and of varying quality, or like guide dogs, they are expensive to train and rare, making them difficult for ordinary people to obtain. Secondly, most of the current guide aids require users to rely on the sound or vibration generated by the device to perceive the surrounding environment, with limited detection space, and some guide aids are uncomfortable to wear and large in size, which greatly affects the user's daily experience. In addition, traditional cameras will violate privacy in scenes such as bedrooms and bathrooms, but for the blind, these places are often the most prone to accidents.

[0003] Ultra Wide band (UWB) is an emerging communication technology that uses nanosecond-wide pulses as wireless communication signals. It has the advantages of high transmission rate, low power consumption, strong anti-interference, and high positioning accuracy. It can realize real-time positioning of moving objects or personnel and is an ideal positioning solution.

[0004] Therefore, it is necessary to provide an intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection to solve the above technical problems. Summary of the invention

[0005] The present invention overcomes the deficiencies of the prior art and provides an intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection, comprising: an ultra-wideband positioning module, a wireless communication module and an alarm module;

[0007] The ultra-wideband positioning module is used to locate the position of the blind and detect the posture of the blind, including: a number of base stations set at various positions in the room, and tags set on clothes and blind sticks; the base stations and tags both include:

[0008] An ultra-wideband unit, used to transmit and receive ultra-wideband signals, obtain the distance between the base station and the tag, determine the relative position between the base station and the tag, and then output the blind person's position information;

[0009] The posture detection unit integrates a three-axis gyroscope and a three-axis accelerometer, is used to output three-axis acceleration and three-axis gyroscope data, and perform posture calculation to detect the posture of the blind person, and then output the posture information of the blind person;

[0010] A control unit, used for controlling the ultra-wideband unit to transmit an ultra-wideband signal, receiving and storing the blind person's position information and the blind person's posture information output by the ultra-wideband unit and the posture detection unit, and sending the blind person's position information and the blind person's posture information to the wireless communication module and the alarm module;

[0011] The wireless communication module is used to send the blind person's position information and the blind person's posture information from the control unit to the terminal;

[0012] The alarm module emits a warning sound and prompts the position according to the blind person's position information and blind person's posture information from the control unit.

[0013] In a preferred embodiment of the present invention, a plurality of base stations are arranged on the walls, floors and furniture of the room.

[0014] In a preferred embodiment of the present invention, the ultra-wideband unit calculates the distance between the tag and the base station through a TWR algorithm based on the round-trip flight time of the ultra-wideband signal between the tag and the base station, and uses a three-sided positioning algorithm to calculate the relative position of the tag and the base station.

[0015] In a preferred embodiment of the present invention, the terminal includes a cloud server and a smart phone.

[0016] In a preferred embodiment of the present invention, the method for performing posture calculation by the posture detection unit comprises the following steps:

[0017] Step 1: Calculate the total acceleration vector including dynamic and static acceleration components based on the output three-axis acceleration and three-axis gyroscope data Among them, A x , A y and A z are the accelerations on the x, y, and z axes respectively;

[0018] Step 2: Calculate the total acceleration vector containing dynamic and static angular velocity components based on the output three-axis acceleration and three-axis gyroscope data Among them, x, y, z are the accelerations on the x, y, and z axes respectively;

[0019] Step 3: Set acceleration thresholds (1g and 1.8g) and divide the blind people's activities into three groups: standing group, normal activity group, and high-density activity group;

[0020] Step 4: Use the threshold method to compare the data with the threshold in step 3, and identify the current blind person's posture information based on the comparison result.

[0021] In a preferred embodiment of the present invention, the normal activity group is classified into multiple normal activities based on the angular velocity threshold, including: walking, sitting, standing, lying down and sitting up;

[0022] The high-density activity group includes: stepping, running and falling; stepping and running are distinguished based on the average peak acceleration threshold (2.1g), and the fall condition is set as the average peak angular velocity greater than 200°.

[0023] In a preferred embodiment of the present invention, the alarm module includes a sound system and a vibration system;

[0024] The sound system includes: a buzzer and a speaker;

[0025] The buzzer is used to start working when the posture information of the blind person reaches the fall condition;

[0026] The speaker, based on the blind person's position information, issues a warning message when the distance between the tag and the obstacle reaches a preset condition, and announces the location and the distance to the obstacle;

[0027] The vibration system includes a micro-motor rotor motor arranged on the blind stick, which drives the blind stick to vibrate based on the position information of the blind person.

[0028] In a preferred embodiment of the present invention, the ultra-wideband unit is also provided with a forward direction danger judgment mechanism: the more obstacles in the forward direction, the greater the ups and downs, and the more tortuous the route, the higher the danger; the fewer obstacles, the smaller the ups and downs, and the straighter the route, the lower the danger; the path danger level is set, and according to the increase of the path danger level, the control unit controls the vibration frequency of the micromotor rotor motor to gradually increase.

[0029] In a preferred embodiment of the present invention, a voice switch is provided at the handle position of the cane, and the voice switch is used to control the voice broadcast function of the speaker.

[0030] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0031] (1) The present invention provides an intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection. The ultra-wideband devices deployed on the blind's clothing, blind sticks and indoor environment can accurately track and locate the position information of the blind. Utilizing the built-in forward path danger judgment mechanism of the blind stick, the system can provide instant and intuitive warnings to the blind according to the danger level, thereby effectively realizing intelligent navigation assistance in indoor environments. At the same time, a posture detection algorithm is also used to monitor the posture of the blind through three-axis acceleration and gyroscope data to ensure that once the blind falls, the system will issue a warning and notify the family. Compared with the prior art, the present invention effectively solves the problems commonly existing in the prior art, such as high cost, insufficient accuracy, large size and potential privacy leakage.

[0032] (2) The present invention is equipped with an ultra-wideband positioning module, which realizes the positioning of the indoor environment and the blind person's position through a number of base stations and tags deployed on the blind person's clothes, and constructs a forward path danger judgment mechanism, which integrates the environmental perception algorithm and path planning logic, and can analyze the blind person's current position, movement trend and potential risk factors in the surrounding environment in real time. Based on this mechanism, the system can intelligently evaluate the danger level on the blind person's forward path, including but not limited to potential threats such as obstacles, edge areas, and height differences.

[0033] (3) The present invention designs differentiated vibration reminder strategies based on different levels of risk assessment results. Specifically, the system will automatically adjust the built-in vibration motor of the cane to output vibration signals of different frequencies, directions and intensities according to the path planning and the level of risk, as an effective means of delivering safety warnings to the blind. This multi-level vibration reminder method is not only intuitive and easy to understand, but also can be flexibly adjusted according to different situations, ensuring that the blind can quickly perceive and respond to potential dangers. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 It is a structural schematic diagram of an intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to a preferred embodiment of the present invention;

[0036] Figure 2 This is a working flow chart of the intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to the preferred embodiment of the present invention;

[0037] Figure 3 is a schematic diagram of the deployment of labels on clothing according to a preferred embodiment of the present invention;

[0038] Figure 4 It is a schematic diagram of the deployment of a tag and a micro-motor rotor motor on a blind stick according to a preferred embodiment of the present invention;

[0039] Figure 5 is a schematic diagram of deployment of a base station in an indoor space according to a preferred embodiment of the present invention;

[0040] Figure 6 is a schematic diagram of a posture detection algorithm of a preferred embodiment of the present invention;

[0041] In the figure: 1. Tag; 2. Clothing; 3. Base station; 4. Blind stick; 5. Micro motor rotor motor. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0044] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0045] like Figure 1 and Figure 2 As shown, the present invention provides a blind intelligent indoor navigation and fall alarm system based on ultra-wideband positioning and posture detection, which is suitable for blind intelligent indoor navigation and includes: an ultra-wideband positioning module, a wireless communication module and an alarm module.

[0046] like Figures 3 to 5As shown, the ultra-wideband positioning module is used to locate the position of the blind and detect the posture of the blind, including: a number of base stations set at various positions in the room, and tags set on clothes and blind sticks; the base stations and tags both include:

[0047] The ultra-wideband unit preferably uses the DW1000 chip as the transceiver medium to transmit and receive ultra-wideband signals, obtain the distance between the base station and the tag, determine the relative position between the base station and the tag, and then output the blind person's position information.

[0048] Several base stations are set on the walls, floors and furniture of the room, that is, on objects that are obstacles in the room. Further, at the location where the base station is set, an ID is set for the base station, indicating the name of the object where it is located, which can be used to build indoor space modeling.

[0049] The ultra-wideband unit calculates the distance between the tag and the base station based on the round-trip flight time of the ultra-wideband signal between the tag and the base station through the TWR algorithm, and calculates the relative position of the tag and the base station using the three-sided positioning algorithm.

[0050] The control unit preferably uses an STM32F103C8T6 chip, which is used to control the ultra-wideband unit to transmit an ultra-wideband signal, receive and store the blind person's position information and blind person's posture information output by the ultra-wideband unit and the posture detection unit, and send the blind person's position information and blind person's posture information to the wireless communication module and the alarm module.

[0051] Furthermore, the ultra-wideband positioning module also includes an ultra-wideband transmitting antenna, whose frequency band is the same as that of the ultra-wideband antenna, both of which are ultra-wideband frequency bands.

[0052] like Figure 6 As shown, the posture detection unit preferably uses an IMU chip ICM42605, which integrates a three-axis gyroscope and a three-axis accelerometer, is used to output three-axis acceleration and three-axis gyroscope data, and perform posture calculation to detect the posture of the blind person, and then output the blind person's posture information.

[0053] Furthermore, the falling process is divided into three states: "imbalance", "impact" and "stationary". According to the scenario, the falling can also be divided into falling from a support such as a bed or chair, falling when going up or down stairs, slipping, tripping, etc. However, no matter in which case the person falls, the acceleration, angular velocity of rotation and relative position of the person to the wall and the ground will change dramatically. Furthermore, the method for performing posture calculation by the posture detection unit includes the following steps:

[0054] Step 1: Calculate the total acceleration vector including dynamic and static acceleration components based on the output three-axis acceleration and three-axis gyroscope data Among them, A x , A y and Az are the accelerations on the x, y, and z axes respectively.

[0055] Step 2: Calculate the total acceleration vector containing dynamic and static angular velocity components based on the output three-axis acceleration and three-axis gyroscope data Among them, x, y, and z are the accelerations on the x, y, and z axes respectively.

[0056] Step 3: Set acceleration thresholds (1g and 1.8g) and divide the blind people's activities into three groups: standing group, normal activity group, and high-density activity group.

[0057] Furthermore, the normal activity group is classified into multiple normal activities based on the angular velocity threshold (50°, 130°), including: walking, sitting, standing, lying down and sitting up.

[0058] The high-intensity activity group included: stepping, running, and falling; stepping and running were distinguished based on the average peak acceleration threshold (2.1g), while the fall condition was set as the average peak angular velocity greater than 200°.

[0059] Step 4: Use the threshold method to compare the data with the threshold in step 3, and identify the current blind person's posture information based on the comparison result.

[0060] Furthermore, once the distance between the blind person's head, hands, etc. and the ground or wall decreases rapidly, combined with the result of posture detection, it will be determined as a fall process. Therefore, whether it is a fast fall, a slow fall, or a fall from the bed, or a fall in different postures such as lying on the back, sideways, and prone, it can be monitored in real time and an alarm can be issued. At the same time, the fall location and posture will be notified to the family.

[0061] It is worth noting that the ultra-wideband positioning module also includes a shell and a PCB board. The control unit, ultra-wideband unit and posture detection unit are all integrated on the PCB board and arranged inside the shell. The PCB board is connected to the shell and is glued or fixed with screws, and is used as a base station and a tag respectively.

[0062] The wireless communication module is preferably composed of an ESP8266WiFi module, which is used to send the blind person's position information and blind person's posture information from the control unit to the terminal; the terminal includes a cloud server and a smart phone. The data signal sent by the ultra-wideband positioning module can be received by other systems other than itself. After data storage and processing by the control unit, the blind person's position information and blind person's posture information are sent to the wireless communication module. Once the blind person falls, the blind person's position information and blind person's posture information will be immediately sent to the family's mobile phone via WiFi.

[0063] The alarm module issues a warning sound and prompts the position according to the blind person's position information and posture information from the control unit.

[0064] Furthermore, the alarm module includes a sound system and a vibration system.

[0065] The sound system includes: buzzer and speaker.

[0066] The buzzer is used to start working when the blind person's posture information reaches the falling condition.

[0067] The speaker, based on the blind person's position information, issues a warning message when the distance between the tag and the obstacle reaches a preset condition, and announces the location and the distance to the obstacle.

[0068] The vibration system includes a micro-motor rotor motor arranged on the blind stick, which drives the blind stick to vibrate based on the position information of the blind person.

[0069] Furthermore, the control unit is connected to the micro motor rotor motor through the GPIO pin, and then connected to the blind stick. The control unit controls the micro motor rotor motor through a PWM signal, so that the blind stick vibrates at different frequencies.

[0070] The ultra-wideband unit is also equipped with a forward path danger judgment mechanism: the more obstacles in the forward direction, the greater the ups and downs, and the more tortuous the route, the higher the danger; the fewer obstacles, the smaller the ups and downs, and the straighter the route, the lower the danger; set the path danger level, and as the path danger level increases, the control unit controls the vibration frequency of the micro-motor rotor motor to gradually increase. In safe conditions, the cane will not vibrate. As the danger level increases, the vibration frequency will gradually increase, and vice versa. When the distance to the wall and obstacles is close, the speaker will issue a warning message to inform the blind person of the location and the distance between the obstacle to remind the blind person to pay attention to safety.

[0071] Furthermore, a voice switch is provided at the handle position of the blind stick, and the voice switch is used to control the voice broadcast function of the speaker.

[0072] In summary, the present invention provides an intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection, which accurately tracks and locates the position information of the blind through ultra-wideband devices deployed on the blind's clothing, blind sticks and indoor environments. Utilizing the built-in forward path danger judgment mechanism of the blind stick, the system can provide immediate and intuitive warnings to the blind according to the level of danger, thereby effectively realizing intelligent navigation assistance in indoor environments. At the same time, a posture detection algorithm is also used to monitor the posture of the blind through three-axis acceleration and gyroscope data to ensure that once the blind falls, the system will issue a warning and notify the family. Compared with the prior art, the present invention effectively solves the problems commonly found in the prior art, such as high cost, insufficient accuracy, large size and potential privacy leakage.

[0073] The above is based on the ideal embodiment of the present invention. Through the above description, relevant personnel can make various changes and modifications without departing from the technical concept of the present invention. The technical scope of the present invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. An intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection, comprising: The ultra-wideband positioning module, wireless communication module and alarm module are characterized by: The ultra-wideband positioning module is used to locate the position of the blind and detect the posture of the blind, including: a number of base stations set at various positions in the room, and tags set on clothes and blind sticks; the base stations and tags both include: An ultra-wideband unit, used to transmit and receive ultra-wideband signals, obtain the distance between the base station and the tag, determine the relative position between the base station and the tag, and then output the blind person's position information; The posture detection unit integrates a three-axis gyroscope and a three-axis accelerometer, is used to output three-axis acceleration and three-axis gyroscope data, and perform posture calculation to detect the posture of the blind person, and then output the posture information of the blind person; A control unit, used for controlling the ultra-wideband unit to transmit an ultra-wideband signal, receiving and storing the blind person's position information and the blind person's posture information output by the ultra-wideband unit and the posture detection unit, and sending the blind person's position information and the blind person's posture information to the wireless communication module and the alarm module; The wireless communication module is used to send the blind person's position information and the blind person's posture information from the control unit to the terminal; The alarm module emits a warning sound and prompts the position according to the blind person's position information and blind person's posture information from the control unit.

2. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 1, characterized in that: A number of the base stations are arranged on the walls, floors and furniture of the room.

3. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 1, characterized in that: The ultra-wideband unit calculates the distance between the tag and the base station by a TWR algorithm based on the round-trip flight time of the ultra-wideband signal between the tag and the base station, and calculates the relative position of the tag and the base station by a three-sided positioning algorithm.

4. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 1, characterized in that: The terminal includes a cloud server and a smart phone.

5. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 1, characterized in that: The method for performing posture calculation by the posture detection unit comprises the following steps: Step 1: Calculate the total acceleration vector including dynamic and static acceleration components based on the output three-axis acceleration and three-axis gyroscope data Among them, A x , A y and A z are the accelerations on the x, y, and z axes respectively; Step 2: Calculate the total acceleration vector containing dynamic and static angular velocity components based on the output three-axis acceleration and three-axis gyroscope data Among them, x, y, z are the accelerations on the x, y, and z axes respectively; Step 3, setting the acceleration threshold, and dividing the blind people's activities into three groups: standing group, normal activity group and high-density activity group; Step 4: Use the threshold method to compare the data with the threshold in step 3, and identify the current blind person's posture information based on the comparison result.

6. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 5, characterized in that: The normal activity group is classified into normal activities based on the angular velocity threshold, including: walking, sitting, standing, lying down and sitting up; The high-density activity group includes: stepping, running and falling; stepping and running are distinguished based on the average peak acceleration threshold, and the fall condition is set as the average peak angular velocity greater than 200°.

7. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 6, characterized in that: The alarm module includes a sound system and a vibration system; The sound system includes: a buzzer and a speaker; The buzzer is used to start working when the posture information of the blind person reaches the fall condition; The speaker, based on the blind person's position information, issues a warning message when the distance between the tag and the obstacle reaches a preset condition, and announces the location and the distance to the obstacle; The vibration system includes a micro-motor rotor motor arranged on the blind stick, which drives the blind stick to vibrate based on the position information of the blind person.

8. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 7, characterized in that: The ultra-wideband unit is also provided with a forward path danger judgment mechanism: the more obstacles there are in the forward direction, the greater the ups and downs, and the more tortuous the route is, the higher the danger is; the fewer obstacles there are, the smaller the ups and downs, and the straighter the route is, the lower the danger is; the path danger level is set, and according to the increase of the path danger level, the control unit controls the vibration frequency of the micromotor rotor motor to gradually increase.

9. The intelligent indoor navigation and fall alarm system for the blind based on ultra-wideband positioning and posture detection according to claim 7, characterized in that: A voice switch is provided at the handle position of the blind stick, and the voice switch is used to control the voice broadcast function of the speaker.

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