A robot positioning and following method based on wireless signals

Abstract

The present application relates to the technical field of following service robot positioning, in particular to a robot positioning and following method based on wireless signal, which is suitable for an environment with multiple rooms and corridors connecting the rooms outside the rooms, comprising hardware deployment: including corridor area division, base station deployment and position coordinate system design; taking a chest card and / or a bracelet as a signal generator, each base station obtains real-time ranging of the chest card and / or the bracelet by reading the signal of the chest card and / or the bracelet, and uses a following algorithm to determine the current position and moving direction of the chest card and / or the bracelet. The present application uses uwb signal to realize short-distance accurate ranging, and simultaneously adopts a base station deployment mode of area division, greatly reducing the instability of uwb signal in long-distance transmission; through the mode of wireless ranging combined with point position auxiliary information, simple and fast positioning is realized, which is not only suitable for hospital inpatient areas, but also applicable to indoor scenes in other fields such as catering and accommodation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of following service robot positioning, in particular to a robot positioning and following method based on wireless signals. BACKGROUND

[0002] At present, the intelligent following robot develops very fast in China, and has a large number of applications in the transportation service field. The current following robot mainly searches the position of the following target through the sensors or radar installed on the robot itself. The disadvantage of this method is that the moving speed of the robot is limited in order to realize the obstacle avoidance function. When the following target moves quickly or turns, due to the limited scanning range of the sensor and radar and the weak temporary reaction ability, the robot is likely to lose the target. Once the target is lost, the robot is difficult to find the target again to realize the continuous following unless the target returns to the vicinity of the robot.

[0003] Ultra-Wideband (UWB) technology is currently the leading centimeter-level high-precision positioning technology in indoor positioning technology, and is widely used in many fields such as valuable goods warehouse management, mine personnel safety monitoring, robot path planning optimization, etc. Although it supports high-precision positioning in a short distance, for a complex indoor scene composed of a large number of rooms, when encountering a wall blockage, its ranging value will often be abnormal or even disappear. For example, sometimes nurses need to use medical instruments to directly perform various examinations on patients in the ward. However, these medical instruments are mostly heavy, which greatly increases the burden of nurses in their daily work. Therefore, a ward service robot is needed to assist nurses in carrying instruments for medical examination. However, the hospital ward is composed of a large number of rooms, and at present, in order to realize positioning in different rooms, a base station needs to be installed in each room, resulting in high cost. In addition to the cost, the ranging signal of UWB is not stable in continuous transmission at a long distance, especially for a public scene such as a hospital with a large number of signal interferences. In actual testing, as long as there is a blockage in the area, the signal transmission will be mutated to 0 at more than 20 meters, which makes UWB not good for long-time real-time positioning in a complex indoor scene composed of a large number of rooms. SUMMARY

[0004] The technical problem to be solved by the present application is: in order to overcome the above technical problems, the present application provides a robot positioning and following method based on wireless signals, which can obtain ranging information based on wireless signals and realize long-time real-time following service for users in various indoor scenes.

[0005] The technical scheme adopted by the present application to solve the technical problem is: a robot positioning and following method based on wireless signals, suitable for an environment with multiple rooms and a corridor connecting outside the rooms, comprising the following steps:

[0006] Step 1: Hardware deployment: including corridor area division, base station deployment, and position coordinate system design;

[0007] Step 1.1: Corridor area division: divide the corridor into n continuous areas along its length direction, and divide each area into multiple continuous blocks to achieve more accurate positioning;

[0008] Step 1.2: Base station deployment: install base stations at the left and right boundaries of each area;

[0009] Step 1.3: Position coordinate system design: independently position each area of the corridor, and establish a three-dimensional sub-coordinate system with the two base stations on both sides of the area as the center point; based on the ranging values of the two base stations and the pre-stored room and corridor point information, jointly position to determine the user's moving direction, which block in the current area, and whether to enter the room; when the user moves to an area of the corridor, use the left and right base stations of the current area for positioning;

[0010] Step 2: Based on the hardware deployment of step 1, use a chest card and / or a bracelet as a signal generator, and each base station obtains the real-time ranging of the chest card and / or bracelet by reading the signal of the chest card and / or bracelet, uses a following algorithm to determine the current position and moving direction of the chest card and / or bracelet, and the robot updates the specific position in the block as the minimum unit, that is, when the block of the chest card and / or bracelet changes, the position is updated, and if the block does not change, the position is not updated. The signal emitted by the chest card and / or bracelet is an ultra-wideband (UWB) signal, and the base station is a UWB positioning base station.

[0011] Step 2 includes data table design and following algorithm design;

[0012] Data table design: based on the hardware deployment of step 1, design a corridor point table and a room point table to assist the algorithm in realizing positioning, and pre-store the room and corridor point information in the corridor point table and the room point table; the corridor point table uniquely identifies a block by block ID, and stores the position information of each block on the corridor; the room point table uniquely identifies a room by room ID, and stores the position information of each room;

[0013] Following algorithm design, including the following steps:

[0014] Step 2a.1: Following scene judgment: determine whether the current following scene is a corridor or a room according to the read data;

[0015] After following scene judgment, perform corridor positioning or room positioning according to the following scene:

[0016] In the corridor positioning, the ranging signals acquired by the left and right base stations of the area are not blocked, and the position and moving direction of the chest card and / or bracelet are positioned according to the ranging value changes of the left and right base stations of the current area;

[0017] In the room positioning, the ranging signals acquired by the left and right base stations of the current area are blocked, and when the user wearing the chest card and / or bracelet enters the room, the ranging signal of the base station deployed on the corridor will abnormally increase or even disappear. According to the last valid ranging before the abnormal change of the ranging signal, that is, the ranging at the door of the room, the room entered by the chest card and / or bracelet is judged.

[0018] Step 2a.2: Corridor following logic judgment: when the bracelet or chest card moves in the corridor, the signal blocking effect is small, the distance between each base station and the chest card and / or bracelet can be measured in real time, and a signal disturbance error of about 1 meter will be generated during the movement in the corridor. The corridor area where the chest card and / or bracelet is located is judged in real time, and the specific position of the chest card and / or bracelet is judged in real time.

[0019] Step 2a.2.1: Real-time judgment of the corridor area where the chest card and / or bracelet is located: when the chest card and / or bracelet moves continuously in the corridor, the ranging values of the base stations in each area of the corridor are analyzed to judge the corridor area where it is located. When the sum of the ranging values of the left and right boundary base stations in a region is within the range of the region length ± the corridor signal disturbance error, since the chest card and / or bracelet is not in other regions, the ranging values of the left and right base stations of other regions all exceed the region length + the corridor signal disturbance error, it is determined that the current position of the chest card and / or bracelet is in the region.

[0020] Step 2a.2.2: Real-time judgment of the specific position of the chest card and / or bracelet: positioning based on the ranging of the left and right base stations of the region and the corridor information table; after the user wearing the chest card and / or bracelet turns on the chest card and / or bracelet, under the environment of the hospital inpatient area, the user generally enters the corridor from the nurses' station after turning on the chest card and / or bracelet. According to the ranging values of the left and right boundary base stations of the current area, the chest card and / or bracelet is positioned in which block of the current area and in what state, including stationary, moving left, moving right, if it is found that the block where the chest card and / or bracelet is located has changed, the new specific position is sent to the robot.

[0021] Step 2a.3: Room following logic judgment: according to the division of the corridor area, the rooms that the user needs to enter are grouped according to the corridor area corresponding to the door of the room. If the user wants to enter a certain room, he must enter from the corridor area where the room belongs. Therefore, according to the signal change characteristics that the ranging value will abnormally increase or become 0 when the base station ranging is blocked, based on the ranging information of the base stations on both sides of the corridor area where the user is currently located and combined with the room point information of the corresponding area, the room entered by the user wearing the chest card and / or bracelet is judged.

[0022] In step 1.1, the corridor area is divided into n regions each having a length of 16-20 meters, where the length of a region refers to the length along the length direction of the corridor. Since the moving track of a user is variable and unpredictable, in order to avoid invalid movement of the robot caused by repeated short-distance movement of the user, the length of each region is between 6-8 meters, and the robot is only notified of a new position when the user moves from one region to another.

[0023] In step 1.2, one base station is installed at each of the left and right boundaries of each region, and a total of n+1 base stations are installed, each of which is arranged at a ceiling position on the side of the corridor.

[0024] The application is suitable for a hospital inpatient area environment. In the hospital inpatient area environment, a base station is installed at the entrance of the nurses' station. In room positioning, the nurses' station is different from the patient room and belongs to a semi-open space, and has the highest priority. When a user wearing a chest card and / or a bracelet returns to the nurses' station, if the ranging signal of the base station on the corridor abnormally increases or even disappears, the priority is to determine whether the chest card and / or the bracelet return to the nurses' station. By reading the distance between the chest card and / or the bracelet and the base station at the entrance of the nurses' station, it is determined whether the user wearing the chest card and / or the bracelet returns to or leaves the nurses' station.

[0025] The base station at the entrance of the nurses' station is arranged at a position 2-4 meters, preferably 3 meters, inward from the entrance of the nurses' station.

[0026] The user of the robot wears a chest card and / or a bracelet, and uses a single-antenna base station to obtain distance information of the user of the robot relative to the base station in real time through the wireless signal provided by the chest card and / or the bracelet.

[0027] The application uses a single-antenna base station based on uwb ranging to obtain the ranging value through the uwb signal provided by the chest card and / or the bracelet, and obtains the distance information of the user of the robot relative to the base station in real time.

[0028] The application is suitable for a hospital inpatient area. Indoor scenes in other fields such as catering and accommodation can also be applicable. In order to be applicable to different application scenarios, a base station can be added at a special point on the corridor. For example, a base station is installed at the entrance of the nurses' station in the hospital inpatient area to be applicable to the normal use scenario of nurses in the hospital inpatient area environment.

[0029] The robot positioning and following method based on wireless signals provided by the application has the following advantages:

[0030] The robot positioning and following method based on wireless signals provided by the application has the following advantages:

[0031] (1) The robot following algorithm that does not rely on the robot to actively detect the target and combines multiple wireless ranging signals in the area to position and follow the target in real time avoids the problem that the robot loses the target and is difficult to follow again due to the limited detection range and weak temporary response when the robot actively detects.

[0032] (2) The wireless signal positioning algorithm based on area division first determines the area where the user wearing a badge and / or a bracelet is located according to the ranging of all base stations installed on the corridor, and only needs to use the ranging data provided by the two base stations on the left and right boundaries of the area and the pre-stored corridor and room point information to assist in positioning to achieve simple and fast positioning. This not only overcomes the problem of unstable transmission of wireless signals over long distances, but also maximizes the demand for ranging data and the complexity of calculation when positioning the target, and realizes the positioning function of determining the user's position in different rooms and corridors only by using the wireless signals of the corridor.

[0033] (3) The method can realize low-cost and accurate following for a long time in a large and complex indoor scene composed of a large number of rooms. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a flowchart of the robot positioning and following method based on wireless signals provided by the application.

[0035] Figure 2 is a schematic diagram of the area L0 position coordinate system of a specific embodiment of the application applied to a hospital inpatient area environment.

[0036] Figure 3This is a schematic diagram of the hardware deployment of a specific embodiment of the present invention applied in a hospital inpatient area environment.

[0037] Figure 4 This is a schematic diagram of the deployment of a nurse station base station in a specific embodiment of the present invention applied to a hospital inpatient area.

[0038] Figure 5 This is a flowchart of the scene determination process in this invention.

[0039] Figure 6 This is a flowchart of the corridor following logic determination in this invention.

[0040] Figure 7 This is a design drawing of a continuous block within a corridor in a specific embodiment of the present invention applied to a hospital inpatient area.

[0041] Figure 8 This is a flowchart of the ward follow-up logic decision process in this invention. Detailed Implementation

[0042] The invention will now be described in further detail with reference to the accompanying drawings. It should be emphasized that the following description is merely exemplary and not intended to limit the scope or application of the invention.

[0043] like Figure 1 As shown, the present invention provides a robot localization and following method based on wireless signals, applicable to environments with multiple rooms connected by corridors, and includes the following steps:

[0044] Step 1: Hardware deployment: This includes corridor area division, base station deployment, and location coordinate system design.

[0045] Step 1.1: Corridor area division: Divide the corridor along its length into n consecutive areas. To achieve more accurate positioning, each area is further divided into multiple consecutive blocks.

[0046] Step 1.2: Base Station Deployment: Install base stations at the left and right boundaries of each area; the left and right boundaries refer to the boundaries between two adjacent areas and the edge boundaries of the first and last areas. The deployment locations of each base station are as follows: Figure 3 As shown. Figure 3 In the illustrated embodiment, the corridor is divided into four areas L0, L1, L2, and L3, and a total of five base stations J0, J1, J2, J3, and J4 are installed in the corridor. Simultaneously, in the hospital inpatient area environment, a base station J5 is also installed at the entrance of nurse station 100. The six base stations are connected via network cables to form a local area network. Base station J5 at the entrance of nurse station 100 is positioned at a distance Ln from the entrance of nurse station 100, preferably Ln is 3 meters. Figure 3 and 4 As shown, Figure 3 and4 The position of the arrow is the entrance of the nurses' station 100, and the direction indicated by the arrow is the direction of entering the nurses' station 100.

[0047] The chest card and / or the bracelet are used as signal generators, each base station obtains real-time ranging of the chest card and / or the bracelet by reading the signals of the chest card and / or the bracelet, the real-time ranging of six base stations is read by reading the ranging for 5 times per second, and the current position and moving direction of the chest card and / or the bracelet are determined by using a following algorithm; the deployment scheme is as shown in Figure 3

[0048] Step 1.3: Design of position coordinate system: Each area of the corridor is independently positioned, and a three-dimensional sub-coordinate system is respectively established with two base stations on both sides of the area as the center point, for example, the corridor width direction is taken as the x axis, the corridor length direction is taken as the y axis, and the direction perpendicular to the plane of the corridor is taken as the z axis. Based on the ranging values of the two base stations and the pre-stored room and corridor point information, joint positioning is performed to determine the moving direction of the user, which block in the current area, and whether to enter the room; when the user moves to an area of the corridor, the left and right base stations of the current area are used for positioning; taking area L0 as an example, as shown in Figure 2

[0049] Step 2: Based on the hardware deployment of step 1, the chest card and / or the bracelet are used as signal generators, each base station obtains real-time ranging of the chest card and / or the bracelet by reading the signals of the chest card and / or the bracelet, and the current position and moving direction of the chest card and / or the bracelet are determined by using a following algorithm, and the robot updates the specific position in the block as the minimum unit, that is, the position is updated when the block of the chest card and / or the bracelet changes, and the position is not updated when the block does not change. The signal emitted by the chest card and / or the bracelet is an ultra-wideband uwb signal.

[0050] Step 2 includes data table design and following algorithm design;

[0051] Data table design: based on the hardware deployment of step 1, a corridor point table and a room point table are designed to assist the algorithm to realize positioning, and the room and corridor point information is pre-stored in the corridor point table and the room point table; the corridor point table uniquely identifies a block by block ID, and stores the position information of each block on the corridor; the room point table uniquely identifies a room by room ID, and stores the position information of each room.

[0052] ​​The corridor point position table includes the fields: area_id is a block ID, jz_area_loc is a region ID, area_loc is a block point position value, area_left_border is a block left border, area_right_border is a block right border, area_left_neigh is a left neighboring block, and area_right_neigh is a right neighboring block. The area_id uniquely identifies a block, and the jz_area_loc indicates which region of the corridor the block belongs to. The area_left_border and the area_right_border are the left border base station ranging and the right border base station ranging of the block in the region, respectively. The area_left_border represents the distance from the block left border to the region left border, which is obtained by ranging the left border base station of the region. The area_right_border represents the distance from the block right border to the region right border, which is obtained by ranging the right border base station of the region. By ranging the two border base stations of the region, the border position of the block can be more accurately determined. The area_left_neigh and the area_right_neigh represent the left and right blocks adjacent to the border of the block. According to the hardware deployment scheme, the corridor point position information of the specific embodiment of the present application is shown in Table 1, and cor01-cor08 in Table 1 correspond to block 1-block 8 in the corridor, respectively. Figure 3

[0053] Table 1

[0054]

[0055] The present embodiment is applied to a hospital inpatient area environment, and the room point position table is also the ward point position table, which includes the fields: bed_number is a ward ID: ward number + bed number information, jz_area_loc is a corridor region ID, room_loc is a ward point position, door_left_dis is a left base station ranging of a ward door, and door_right_dis is a right base station ranging of the ward door. The bed_number uniquely identifies a ward, and the jz_area_loc indicates which region of the corridor the ward belongs to. The door_left_dis and the door_right_dis are the left border base station ranging and the right border base station ranging of the ward in the region, respectively. The door_left_dis represents the distance from the ward door to the region left border, which is obtained by ranging the left border base station of the region. The door_right_dis represents the distance from the ward door to the region right border, which is obtained by ranging the right border base station of the region. According to the hardware deployment scheme, the ward point position information of the specific embodiment of the present application is shown in Table 2, and 2301 room-2318 room in Table 2 correspond to ward 1-ward 18 in the corridor, respectively. Figure 3 ​2301-2318 rooms under each block in the hospital.

[0056] Table 2

[0057]

[0058] Following the algorithm design, the following steps are included:

[0059] Step 2a.1: Follow the scene judgment: According to the hardware deployment scheme, read the ranging information of six base stations for five times a second for a long time. According to the read data, judge whether the current following scene is a corridor or a room, and in the hospital inpatient environment, including corridor following, room following and returning to the nurse station 100. The specific judgment logic is as shown in Figure 5 .

[0060] After the following scene judgment, the corridor positioning or room positioning is carried out according to the following scene, and in the hospital inpatient environment, the room includes the ward and the nurse station 100:

[0061] In the corridor positioning, the ranging signals obtained by the left and right base stations of the area are all unobstructed, and the position and moving direction of the chest card and / or the wristband are positioned according to the ranging value changes of the left and right base stations of the current area;

[0062] In the room positioning, the ranging signals obtained by the left and right base stations of the current area are obstructed, and when the user wearing the chest card and / or the wristband enters the room, the ranging signal of the base station deployed on the upper part of the corridor will abnormally become larger or even disappear. According to the last valid ranging before the abnormal change of the ranging signal, that is, the room door ranging, the room into which the chest card and / or the wristband enters is judged.

[0063] Step 2a.2: Corridor following logic judgment: According to the hardware deployment scheme, the corridor is divided into four areas, and each area has a base station at the left and right boundaries; the base station is installed at the ceiling on one side of the corridor, and the signal obstruction has little effect on the wristband or chest card when moving in the corridor, so the distance between each base station and the chest card and / or the wristband can be measured in real time. When moving in the corridor, a signal disturbance error of about 1 meter will be generated. The corridor area where the chest card and / or the wristband is located is judged in real time, and the specific position of the chest card and / or the wristband is judged in real time, as shown in Figure 6 .

[0064] Step 2a.2.1: Real-time determination of the corridor area where the chest card and / or bracelet is located: when the chest card and / or bracelet moves continuously in the corridor, the corridor area where it is located is first determined by analyzing the ranging values of the six base stations in each area of the corridor. When the sum of the ranging values of the left and right boundary base stations in an area is within the range of the length of the area ± the signal disturbance error of the corridor, and the chest card and / or bracelet is not in other areas, the ranging values of the left and right base stations in other areas all exceed the length of the area + the signal disturbance error of the corridor, then it is determined that the current position of the chest card and / or bracelet is in the area. The specific determination logic is as follows:

[0065] Initialize the minimum error to 100.0, the temporary error to 0.0, and the current area to -1. Traverse all base station ranging values. If the ranging values of base station Ji and base station J(i+1) are both greater than 0, and the sum of the two is within the length of corridor area Li ± signal disturbance error, then update the temporary error as:

[0066] Temporary error = |(base station Ji ranging value + base station J(i+1) ranging value) - (length of corridor area Li + signal disturbance error)|.

[0067] After updating the temporary error, compare the temporary error with the minimum error. If the temporary error is less than the minimum error, update the value of the minimum error to the current temporary error, and update the current area to Li, as shown in the embodiment of Figure 3 , where i is a natural number from 0 to 3.

[0068] Step 2a.2.2: Real-time determination of the specific position of the chest card and / or bracelet: based on the ranging of the left and right base stations of the area and the corridor information table to determine the position; after the user wearing the chest card and / or bracelet turns on the chest card and / or bracelet, the user generally enters the corridor from the nurse station 100 in the hospital ward environment. According to the ranging values of the left and right boundary base stations of the current area, determine which block the chest card and / or bracelet is in and what state it is in, including stationary, moving left, and moving right. If it is found that the block where the chest card and / or bracelet is located has changed, send the new specific position to the robot. As shown in Figure 3 , the corridor is divided into four areas L0, L1, L2, and L3. There are five base stations J0, J1, J2, J3, and J4 installed in the corridor. Area L0 is divided into block 1 and block 2. Area L1 is divided into block 3 and block 4. Area L2 is divided into block 5 and block 6. Area L3 is divided into block 7 and block 8. The specific determination logic is as follows:

[0069] Initialize the current point to the last time point, the reference block to the last time block, the left and right boundaries of the block to the left and right boundaries of the last time block, and the reference step length to 0.9 meters. Read the left and right base station ranging values of the area where the user wearing the chest card and / or bracelet is currently located, and compare them with the left and right base station ranging values at the last time.

[0070] (1) Stationary judgment

[0071] If the left base station ranging change or the right base station ranging change is less than the reference step length, it is judged that the user is in a relatively stationary state, and the point is not updated.

[0072] (2) Left walk judgment

[0073] If the left and right base station ranging values are not 0, and the left base station ranging change is positive and the change value is greater than the reference step length, and the right base station ranging change is negative and the change value is also greater than the reference step length, it is judged to be walking to the left.

[0074] If the left boundary block of the corridor is reached, the point is not updated. If the left boundary of the current block is not crossed, the point is not updated; if the left boundary of the current block is crossed, the point is updated to the left adjacent block of the current block.

[0075] (3) Right walk judgment

[0076] If the left and right base station ranging values are not 0, and the right base station ranging change is positive and the change value is greater than the reference step length, and the left base station ranging change is negative and the change value is also greater than the reference step length, it is judged to be walking to the right.

[0077] If the right boundary block of the corridor is reached, the point is not updated. If the right boundary of the current block is not crossed, the point is not updated; if the right boundary of the current block is crossed, the point is updated to the right adjacent block of the current block.

[0078] Step 2a.3: Room following logic judgment: according to the division of the corridor area, the rooms that the user needs to enter are grouped according to the corridor area corresponding to the door of the room, as shown in Figure 3 , the entire corridor area includes 2301-2318 a total of 18 rooms; as shown in Figure 7 , take area L0 as an example, the rooms in this section of the corridor area include: 2301 room, 2302 room, 2303 room, 2304 room and 2305 room, and the door positions are shown by triangles in the figure. If the user wants to enter a room, he must enter from the corridor area where the room belongs. Therefore, according to the signal change characteristics that the base station ranging will abnormally increase or become 0 when encountering an obstruction, based on the ranging information of the base stations on both sides of the corridor area where the user is currently located and combined with the room point information of the corresponding area, the room entered by the user wearing the chest card and / or bracelet is judged, and the judgment logic is as follows Figure 8The algorithm implementation process is as follows:

[0079] The current corridor area and current point of the user wearing the badge and / or bracelet are acquired. The ranging value of the last left base station in the area before entering the room is compared.

[0080] (1) Corridor anomaly

[0081] If the ranging anomaly is restored, the room point judgment is not performed, the anomaly count is set to 0, and the corridor following logic is still processed.

[0082] (2) Already entered the room

[0083] If the ranging anomaly occurs and the current point is the room point, it indicates that the room has been entered, and the point is not updated. If it is not the room point, the continuous anomaly count is started, and the ranging data will be abnormal after entering the room.

[0084] (3) Room judgment

[0085] If the current point is not the room point and the continuous anomaly count is greater than 5 times, the room judgment is performed. First, the SQL query is performed according to the current area, and the room list in the current area is obtained according to the corridor point table and the room point table. The absolute value of the difference between the comparison ranging and the ranging of the left base station of each room door in the area is calculated, and the room with the smallest absolute value is taken as the current room point.

[0086] In step 1.1, the corridor area is divided into n lengths of 16-20 meters, where the length of the area refers to the length along the length of the corridor, that is Figure 3 The length indicated by the curly braces. Figure 3 In the above, the corridor is divided into 4 areas, area L0 is 19.8 meters, area L1 is 16 meters, area L2 is 16 meters, and area L3 is 19 meters. Since the moving track of the user is variable and unpredictable, in order to avoid the invalid movement of the robot caused by the repeated movement of the user in a short distance, the length of each block is between 6-8 meters, and the robot is only notified of the new position when the user moves from one block to another.

[0087] The present application is suitable for hospital inpatient area environment, and under the hospital inpatient area environment, a base station is installed at the entrance of the nurse station 100. In room positioning, the nurse station 100 is different from the room and belongs to a semi-open space. For example Figure 5As shown, the priority judgment of the nurse station 100 is the highest in the following scene judgment flow, when the user wearing the chest card and / or bracelet returns to the nurse station 100, when the base station ranging signal on the corridor abnormally increases or even disappears, the priority judgment of whether the chest card and / or bracelet returns to the nurse station 100 is performed, and whether the user wearing the chest card and / or bracelet returns or leaves the nurse station 100 is judged by reading the distance between the chest card and / or bracelet and the base station at the entrance of the nurse station 100.

[0088] The user of the robot wears the chest card and / or bracelet, and uses the single-antenna base station based on the uwb signal ranging to obtain the ranging value through the uwb signal provided by the chest card and / or bracelet, and the distance information of the user of the robot relative to the base station is obtained in real time.

[0089] The application is suitable for the inpatient area of a hospital, and can also be applied to other indoor scenes such as catering and accommodation. In order to be suitable for different application scenes, the base station can be added at special points on the corridor. For example, in the embodiment of the application, a base station is installed at the entrance of the nurse station 100 to adapt to the normal use scene of the nurse in the hospital inpatient area.

[0090] The following method of the application is different from the traditional following robot, which does not use the sensor on the robot to actively detect the following target, but uses the data provided by the multiple base stations installed indoors to determine the position of the following target and send it to the robot. Only by using several single-antenna base stations to collect the ranging signal of the electronic chest card or bracelet in real time, the movement of the user in a large inpatient area with a corridor length of more than 70 meters and other complex indoor scenes can be tracked in real time for a long time. The position coordinate system is also different from the position coordinate system with the robot as the origin in the traditional positioning method. Each region divided in the corridor is positioned, and a three-dimensional sub-coordinate system is established with the left and right base stations of the region as the center. The left and right base station ranging signals are combined for positioning, and accurate positioning in a small range can be realized to achieve accurate positioning in the whole region. The point position setting method is different from the traditional real-time given position. Only one fixed point position is set in each block with a length of 6 to 8 meters, and the robot is only notified to update the point position when the user moves to the next block. This effectively reduces the invalid movement of the robot caused by the back and forth movement of the user, and is suitable for indoor areas with low real-time demand for positioning. The service robot using the method of the application can increase more functions such as question and answer and propaganda on the basis of the following function, and can better serve people.

[0091] Based on the above ideal embodiments according to the application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the application. The technical scope of the application is not limited to the contents in the specification, and must be determined according to the scope of claims.

Claims

1. A wireless signal-based robot positioning and following method, characterized by, Suitable for multi-room and room outside by the corridor connected environment, comprising the following steps: Step 1: hardware deployment: including corridor area division, base station deployment and position coordinate system design; Step 1.1: corridor area division: the corridor is divided into n continuous regions along its length direction, and each region is divided into a plurality of continuous blocks; Step 1.2: base station deployment: install base station at the left and right boundary of each region; Step 1.3: position coordinate system design: each region of the corridor is independently positioned, and a three-dimensional sub-coordinate system is established respectively with the two base stations on both sides of the region as the center point; based on the ranging values of the two base stations and the pre-stored room and corridor point information, the moving direction of the user, which block in the current region, and whether entering the room are judged; when the user moves to a region of the corridor, the left and right base stations of the current region are used for positioning; Step 2: based on the hardware deployment of step 1, take the chest card and / or bracelet as the signal generator, and each base station obtains the real-time ranging of the chest card and / or bracelet through reading the signal of the chest card and / or bracelet, and determines the current position and moving direction of the chest card and / or bracelet using the following algorithm, and the robot updates the specific position in the block as the minimum unit, and the signal emitted by the chest card and / or bracelet is ultra-wideband (UWB) signal; Step 2 includes data table design and following algorithm design; Data table design: based on the hardware deployment of step 1, design the corridor point table and the room point table to assist the algorithm to realize positioning, and the room and corridor point information is pre-stored in the corridor point table and the room point table; the corridor point table uniquely identifies a block by block ID, and stores the position information of each block on the corridor; the room point table uniquely identifies a room by room ID, and stores the position information of each room; Following algorithm design, comprising the following steps: Step 2a.1: following scene judgment: judging whether the current following scene is a corridor or a room according to the read data; After following scene judgment, corridor positioning or room positioning is performed according to the following scene: In corridor positioning, the position and moving direction of the chest card and / or bracelet are positioned according to the ranging value changes of the left and right base stations of the current region; In room positioning, the room entered by the chest card and / or bracelet is judged according to the last valid ranging before the ranging signal abnormal change; Step 2a.2: corridor following logic judgment: real-time judgment of the corridor region where the chest card and / or bracelet is located and real-time judgment of the specific position of the chest card and / or bracelet; Step 2a.2.1: real-time judgment of the corridor region where the chest card and / or bracelet is located: when the chest card and / or bracelet moves continuously in the corridor, the ranging values of the base stations in each region of the corridor are analyzed to judge the corridor region where the chest card and / or bracelet is located, when the sum of the ranging values of the left and right boundary base stations in a region is within the range of region length ± corridor signal disturbance error, and the ranging values of the left and right base stations of other regions all exceed region length + corridor signal disturbance error, it is determined that the current position of the chest card and / or bracelet is in the region; Step 2a.2.2: Real-time determination of the specific position of the chest card and / or wristband: positioning based on the range of the left and right base stations in the area and the corridor information table; after the user wearing the chest card and / or wristband turns on the chest card and / or wristband, the current area is determined according to the range value of the left and right boundary base stations in the area, and the state of the chest card and / or wristband in the current area is determined, and if it is found that the block where the chest card and / or wristband is located has changed, the new specific position is sent to the robot; Step 2a.3: Room following logic determination: according to the division of the corridor area, the rooms that the user needs to enter are grouped according to the corresponding corridor area of the door, and according to the signal change characteristics of the abnormal large or zero range value of the base station, the range information of the base stations on both sides of the current corridor area of the user is combined with the room point information of the corresponding area to determine the room entered by the user wearing the chest card and / or wristband.

2. The wireless signal based robot positioning and following method of claim 1, wherein, In step 1.1, the corridor area is divided into n areas, each with a length of 16-20 meters; the length of each block is 6-8 meters, and the robot is only notified of the new position when the user moves from one block to another.

3. The wireless signal based robot positioning and following method of claim 1, wherein, In step 1.2, one base station is installed at the left and right boundaries of each area, a total of n+1 base stations, and each base station is installed on the ceiling near the corridor.

4. The wireless signal based robot positioning and following method of claim 1, wherein, It is suitable for hospital inpatient environment, and in hospital inpatient environment, a base station is installed at the entrance of the nurses' station, and in room positioning, the nurses' station belongs to a semi-open space. When the base station on the corridor has an abnormal large or even disappeared range signal, it is determined whether the chest card and / or wristband returns to the nurses' station, and whether the user wearing the chest card and / or wristband returns or leaves the nurses' station is determined by reading the distance between the chest card and / or wristband and the base station at the entrance of the nurses' station.

5. The wireless signal based robot positioning and following method of claim 1, wherein, The base station at the entrance of the nurses' station is installed 2-4 meters inside the entrance of the nurses' station.

6. The wireless signal based robot positioning and following method of claim 1, wherein, The robot user wears a chest card and / or wristband, and uses a single-antenna base station to obtain the distance information of the robot user relative to the base station in real time through the wireless signal provided by the chest card and / or wristband.

7. The wireless signal based robot positioning and following method of claim 6, wherein, A single-antenna base station based on uwb signal ranging is used to obtain the range value through the uwb signal provided by the chest card and / or wristband, and the distance information of the robot user relative to the base station is obtained in real time.

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