WO2019239132A1

WO2019239132A1 - A location system, method, and calibration method

Info

Publication number: WO2019239132A1
Application number: PCT/GB2019/051632
Authority: WO
Inventors: Robert Lewis
Original assignee: Avire Limited
Priority date: 2018-06-13
Filing date: 2019-06-12
Publication date: 2019-12-19
Also published as: GB2574644B; GB2574644A; GB201809712D0

Abstract

A location system for use in an elevator system, the location system including: a ranging sensor carried by an elevator car of the elevator system, directed toward a sidewall of an elevator shaft of the elevator system, and configured to generate ranging data; and a processing unit configured to: receive the ranging data; identify one or more recognisable elements within the ranging data indicative of the location of the elevator car; and to determine the location of the elevator car based on the or each identified recognisable element.

Description

Title: A location system, method, and calibration method

Description of Invention

Embodiments relate to systems and methods for determining an elevator car position within an elevator shaft.

In order for elevator control systems and information displays to operate correctly, it is necessary to determine the location of an elevator car within an elevator shaft. There is a need, therefore, for systems which determine the elevator car location.

Such location determining systems may be used, for example, to provide information to a display in order to present, on the display, the current location of the elevator car. Such location determining systems may also be used, for example, to notify the elevator control system of the current location of the elevator car for purposes of controlling the movement of the elevator car within the elevator shaft.

There is a need to provide such systems which are reliable and inexpensive. There is also a need to provide systems which can be retrofitted to elevators.

Accordingly, an aspect provides a location system for use in an elevator system, the location system including: a ranging sensor carried by an elevator car of the elevator system, directed toward a sidewall of an elevator shaft of the elevator system, and configured to generate ranging data; and a processing unit configured to: receive the ranging data; identify one or more recognisable elements within the ranging data indicative of the location of the elevator car; and to determine the location of the elevator car based on the or each identified recognisable element.

The ranging sensor may be a LiDAR sensor.

The ranging sensor may be an acoustic sensor.

The processing unit may be configured to identify one or more recognisable elements within the ranging data by comparing the ranging data to a threshold. The processing unit may be configured to identify one or more recognisable elements within the ranging data using one or more stored range data profiles.

A location system may further include a primary sensor configured to determine a direction of travel of the elevator car, wherein the processing unit may be further configured to use the or each identified recognisable elements and the direction of travel to determine a location of the elevator car within the elevator shaft.

The primary sensor may include an air pressure sensor.

The processing unit may be configured to use air pressure data generated by the primary sensor to determine a direction of travel of the elevator car within the elevator shaft.

The air pressure sensor may be configured to generate air pressure data and the processing unit may be configured to determine a location of the elevator car using the air pressure data.

The processing unit may be configured to compare the air pressure data to a predetermined air pressure profile to determine the location of the elevator car.

The processing unit may be configured to compare the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and to determine a confirmed location based on the comparison.

The processing unit may be configured to compare the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and to adjust the predetermined air pressure profile based on the comparison.

The processing unit may be configured to output the determined location as level data to one or more of a controller of the elevator system and a display device, the controller being configured to control movement of the elevator car within the elevator shaft and the display device configured to display a current location of the elevator car.

The location system may further include a backup electrical supply which is configured to provide power to the location system after a main power failure such that the location system may be configured to determine a location of the elevator car after the main power failure. Another aspect provides an elevator system including a location system.

Another aspect provides a method of determining the location of the elevator car for use in an elevator system, the method including: receiving ranging data generated using a ranging sensor carried by an elevator car of the elevator system, directed towards a sidewall of an elevator shaft of the elevator system; identifying, using a processing unit, one or more recognisable elements within the ranging data indicative of the location of the elevator car; and determining, using a processing unit, the location of the elevator car based on the or each identified recognisable element.

The ranging sensor may be a LiDAR sensor.

The ranging sensor may be an acoustic sensor.

Identifying one or more recognisable elements within the ranging data may include comparing the ranging data to a threshold.

Identifying one or more recognisable elements within the ranging data may include using one or more stored range data profiles.

A method may further include: determining a direction of travel of the elevator car, using a primary sensor; and using, by a processing unit, of the or each identified recognisable elements and the direction of travel to determine a location of the elevator car within the elevator shaft.

The primary sensor may include an air pressure sensor.

The method may further comprise using air pressure data, by a processing unit, generated by the primary sensor to determine a direction of travel of the elevator car within the elevator shaft.

The air pressure sensor may be configured to generate air pressure data and the method further includes determining, using a processing unit, a location of the elevator car using the air pressure data. The method may further include comparing, using a processing unit, the air pressure data to a predetermined air pressure profile to determine the location of the elevator car.

The method may further include comparing, using a processing unit, the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and determining, using a processing unit, a confirmed location based on the comparison.

The method may further include comparing, using the processing unit, the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and adjusting the predetermined air pressure profile based on the comparison.

The method may further include outputting, from a processing unit, the determined location as level data to one or more of a controller of the elevator system and a display device, the controller being configured to control movement of the elevator car within the elevator shaft and the display device configured to display a current location of the elevator car.

The method may further include providing power to the location system, using a backup electrical supply, after a main power failure, and determining a location of the elevator car after the main power failure.

Another aspect provides a calibration process for a location system, the method including: controlling the elevator car to perform one or more predetermined movements within the elevator shaft; and recording the ranging data using the ranging sensor during the one or more predetermined movements to generate a ranging data profile.

Embodiments are described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows an elevator system according to some embodiments; Figure 2 shows elevator doors arranged on several levels according to some embodiments; and

Figure 3 shows a location system according to some embodiments.

Embodiments include an elevator system 1 (see figure 1 , for example). The elevator system 1 may be provided in a building and is configured to move one or more objects between levels of the building.

The elevator system 1 may, therefore, include an elevator shaft 1 1 which extends between multiple levels of the building. The elevator system 1 may further include an elevator car 12 located within the elevator shaft 1 1 and configured to move therein between the levels of the building.

The elevator shaft 1 1 may include doors 1 1 1 located at each level (see figure 2, for example), which provide access from a building level to the elevator car 12 (when the elevator car 12 is located at that level). The elevator car 12 may include corresponding doors which are configured to operate in unison, for example, with the doors 1 1 1 of the elevator shaft 1 1— to allow access to the interior of the elevator car 12.

The elevator system 1 may further include an elevator control and drive system 13.

The elevator control and drive system 13 may be configured to drive movement of the elevator car 12 within the elevator shaft 1 1 . The elevator control and drive system 13 may, therefore, include a controller 131 . The controller 131 may be communicatively coupled to a drive sub system 132 of the elevator control and drive system 13 which may be configured to drive the movement of the elevator car 12.

The controller 131 may be communicatively coupled to one or more interface devices 133 which are each configured to enable a user to input a command to control the operation of the elevator system 1— such as the movement of the elevator car 12 within the elevator shaft 1 1. As such, the controller 131 may be configured to receive the command or commands from the one or more interface devices 133 and to control the operation of the drive sub-system 132 accordingly. The or each interface devices 133 may include, for example, at least one car operating panel which may be located within the elevator car 12. The car operating panel may be configured to receive a user selection of a desired destination level. The car operating panel may be configured to receive a user command to open or close the doors 1 1 1 , and/or sound an alarm, and/or activate an emergency intercom. The car operating panel may, therefore, include one or more buttons or a touch-sensitive display panel to enable user input.

The or each interface device 133 may include, for example, at least one call button. The or each call button may be located on a respective level and may be configured to enable a user to call an elevator car 12 to that level so that the user can enter the elevator car 12 and travel to another level using the elevator car 12.

In some embodiments, the or each interface device 133 may be part of a destination control system in which the user identifies themselves to a interface device 133 of the one or more interface devices 133 on a level (e.g. through detection of an identification card for the user, facial recognition of the user, or other biometric information associated with the user, by the interface device 133). The interface device 133 may then determine a desired destination level for that user (e.g. through a stored record of the user’s identity in association with a destination level or through receipt of the destination level from the user (e.g. using one or more buttons or a touch-sensitive display of the interface device 133)).

The elevator system 1 may include one or more display devices 14 which may be configured to display information to users. The one or more display devices 14 may include one or more devices 14 located within the elevator car 12 and/or on a level (e.g. adjacent the doors 1 1 1 ). In some embodiments, the one or more display devices 14 may be part of the elevator control and drive system 13.

The one or more display devices 14 may include, for example, a display on which the current location of the elevator car 12 is presented— which may be a display device 14 located within the elevator car 12 or elsewhere.

In some embodiments, at least one of the or each display devices 14 and at least one of the or each interface device 133 are integrated (to form a display and interface device). Embodiments include a location system 15 (see figure 3, for example) which is configured to determine the location of the elevator car 12 within the elevator shaft 1 1 (e.g. the level at which the elevator car 12 is located).

The location system 15 may be communicatively coupled to the controller 131 such that the location of the elevator car 12— as determined by the location system 15— may be used by the controller 131 in controlling the movement of the elevator car 12 within the elevator shaft 1 1. Accordingly, in some embodiments, the location system 15 is communicatively coupled to the elevator control and drive system 13.

In some embodiments, the location system 15 is communicatively coupled to the one or more display devices 14 and is configured to provide the location determined by the location system 15 to the or each display device 14 (e.g. to be presented to a user on a display of the one or more display devices 14).

The location system 15 is, therefore, configured to generate a location signal which is representative of the determined location.

The location system 15 may be configured to be retrofitted to an existing elevator system 1. The location system 15 may be configured to be retrofitted to an existing elevator car 12. The location system 15 may be substantially carried by the elevator car 12 such that the location system 15 moves with the elevator car 12 within the elevator shaft 1 1 .

The location system 15 may include a ranging sensor 151 which is configured to determine the range of a surface from the ranging sensor 151. Examples of ranging sensors 151 which may be used in embodiments include: a light detection and ranging sensor (a LiDAR sensor, which may use ultraviolet, visible or infrared light, for example), an acoustic ranging sensor (such as an ultrasonic ranging sensor), a radio detection and ranging sensor (a RADAR sensor), or the like (e.g. using another form of electromagnetic signal to determine ranging data).

The ranging sensor 151 is carried by the elevator car 12 such that the ranging sensor 151 moves with the elevator car 12 with respect to the elevator shaft 1 1 . The ranging sensor 151 may be oriented perpendicular to a direction of travel of the elevator car 12 within the elevator shaft 1 1. In other words, the ranging sensor 151 may be oriented perpendicular to a longitudinal axis of the elevator shaft 1 1. The ranging sensor 151 may, therefore, be oriented (i.e. directed) towards a sidewall of the elevator shaft 1 1. The orientation of the ranging sensor 151 is a reference to the direction in which the range of a surface from the ranging sensor 151 is determined.

The ranging sensor 151 may be oriented towards a wall of the elevator shaft 1 1 such that, as the elevator car 12 moves within the elevator shaft 1 1 , that wall of the elevator shaft 1 1 passes the ranging sensor 151.

The ranging sensor 151 may be oriented towards a wall of the elevator shaft 1 1 which includes the doors 1 1 1 , for example.

The ranging sensor 151 may be mounted to the top, bottom, or side of the elevator car 12, for example. In some embodiments the ranging sensor 151 is mounted to the elevator car 12 through the use of a bracket which allows the position of the ranging sensor 151 to be varied (e.g. during configuration before being locked in position) in the direction in which the ranging sensor 151 is configured to sense. As will be appreciated, the ranging sensor 151 has a field of view which is the volume in which the ranging sensor 151 is configured to determine the range of a surface from the ranging sensor 151 . In other words, the bracket may be an adjustable bracket and adjustment may alter the position of the field of view of the ranging sensor 151 relative to the elevator car 12 and a wall of the elevator shaft 1 1.

The ranging sensor 151 may be located such that the sensor 151 does not contact the surface within its field of view which the sensor 151 is configured to sense (e.g. the wall of the elevator shaft 1 1 ).

In some embodiments, the location system 15 may include a plurality of such ranging sensors 151. In such embodiments, there may be more than one type of ranging sensor 151 used - such as one acoustic sensor and one light sensor. However, in other embodiments, all of the ranging sensors 151 are of the same type - in such embodiments, different frequencies of light and/or sound may be used by the ranging sensors 151 to reduce the risk of interference between the ranging sensors 151 of the same type (although other forms of multiplexing are also possible, such as time division multiplexing).

Each of the plurality of ranging sensors 151 may be supported with respect to the elevator car 13 by its own bracket or a bracket shared with at least one other ranging sensor 151. The plurality of ranging sensors 151 may have separate or overlapping fields of view. In some embodiments, two of the ranging sensors 151 may be directed toward different walls of the elevator shaft 1 1 and those two walls may oppose each other across the width of the elevator shaft 1 1 . Such an arrangement may be used, for example, in embodiments in which doors 1 1 1 are located on different walls of the same elevator shaft 1 1 - in which case such doors 1 1 1 are often on opposing sides of the elevator car 12 and, therefore, also of the elevator shaft 1 1 .

The location system 15 (and, in particular, in relevant embodiments the or each ranging sensor 151 ) may be configured, therefore, to generate ranging data. This ranging data represents, at least in part, a range (i.e. distance) of a wall of the elevator shaft 12 from the location system 15 or a part thereof (such as the or each ranging sensor 151 ). Of course, if the wall includes one or more doors 1 1 1 then the ranging data equally represents, at least in part, a range of the or each door from the location system 15 or a part thereof (such as the or each ranging sensor 151 ). The ranging data may include data for more than one ranging sensor 151 and may include data for more than one field of view (which may be distinct (i.e. non-overlapping) or overlapping fields of view. Indeed, in some embodiments, the ranging data is associated with two different walls of the elevator shaft 1 1 in accordance with the orientation of the ranging sensors 151.

The ranging data may represent a map or range data profile of a wall or walls of the elevator shaft 1 1 , for example. In some embodiments, the ranging data represents a map or range data profile corresponding to a ribbon of range information extending along a length of the elevator shaft 1 1 (that length being generally aligned with a longitudinal axis of the elevator shaft 12 and the directions of travel of the elevator car 12 therein).

The location system 15 may include one or more primary sensors 152. The or each primary sensors 152 may be configured to sense an aspect of the environment associated with the elevator car 12 which may be used to assist in determining the location of the elevator car 12 within the elevator shaft 1 1. The or each primary sensor 152 may be configured to sense one or more forces acting on the elevator car 12, such as due to acceleration of the elevator car 12. The one or more primary sensors 152 may include, for example, an air pressure sensor 1521 which is configured to determine the atmospheric (i.e. air) pressure at the location of the elevator car 12 within the elevator shaft 1 1 . The air pressure sensor 1521 may, therefore, be configured to generate air pressure data.

The one or more primary sensors 152 may include a temperature sensor 1523. The temperature sensor 1523 may be used to determine a temperature (such as the air temperature) in the elevator shaft 1 1 (e.g. at the location of the elevator car 12 or elsewhere in the elevator shaft 1 1 ). The temperature sensor 1523 may be configured, therefore, to generate temperature data.

In some embodiments, the one or more primary sensors 152 may include, for example, a direction sensor 1522 which is configured to determine a direction of travel of the elevator car 12 within the elevator shaft 1 1 (e.g. upwards or downwards). The direction sensor 1522 may be in the form of a force sensor which is configured to determine one or more forces acting on the direction sensor 1522 (e.g. due to acceleration upward or downward within the elevator shaft 1 1 ). The direction sensor 1522 may be, for example, a piezoelectric acceleration sensor 1522.

In some embodiments, the pressure sensor 1521 may provide a similar indication of the direction of travel based on changes in air pressure - a decrease in air pressure indicating upward travel and vice versa.

The direction sensor 1522 may therefore be configured to generate direction data, therefore, indicative of the direction of travel of the elevator car 12.

One or both of the pressure sensor 1521 and the direction sensor 1522 may be configured to provide speed data indicative of the speed of travel of the elevator car 12 in the elevator shaft 1 1. This speed data may be generated instead of or in addition to direction data which may be generated by the sensors 1521 ,1522.

In the case of the pressure sensor 1521 , the speed data may be generated based on a rate of change in the measured air pressure over time. In the case of the direction sensor 1522, the speed data may be generated based on a sensed acceleration of the elevator car 12 and a duration of the sensed acceleration of the elevator car 12.

The location system 15 (and, in particular, in relevant embodiments the or each primary sensor 152) may be configured, therefore, to generate primary data (which may include one or more of the temperature data, the air pressure data, and the direction data).

In some embodiments, a processing unit 153 (see below) may be configured to generate the speed data based on the primary data (e.g. using the air pressure data over time to determine a rate of change of air pressure and, therefore, a speed of the elevator car 12). In some other embodiments, the primary data may include the speed data.

The location system 15 may further include a processing unit 153. The processing unit 153 may be communicatively coupled to the or each ranging sensor 151 and/or the or each primary sensor 152. As such, the processing unit 153 may be configured to receive the ranging data and/or the primary data.

The processing unit 153 may be carried by the elevator car 12 or may be mounted at a substantially fixed location with respect to the elevator shaft 1 1. In some embodiments, the processing unit 153 may be located in a control room of the elevator system 1 - e.g. in the same location as the controller 131.

The processing unit 153 may be communicatively coupled to a computer readable medium 1531 of the location system 15. The computer readable medium 1531 may be a tangible computer readable medium. The computer readable medium 1531 may be configured to store one or more instructions which, when executed, cause the operations of the processing unit 153 - as described herein - to be performed. The computer readable medium 1531 may be configured to store one or more ranging data profiles.

The processing unit 153 may be configured to generate level data indicative of the current level (i.e. position) of the elevator car 12 as determined by the processing unit 153 - see below. The processing unit 153 may, therefore, be communicatively coupled to the elevator control and drive system 13 (e.g. the controller 131 ) and configured to output the level data thereto. In some embodiments, the processing unit 153 is communicatively coupled to the or each display device 14 and configured to output the level data thereto for display.

The processing unit 153 may be configured to generate the level data based on the ranging data and/or the primary data, as described herein.

The or each ranging sensor 151 may, as described above, be oriented towards a wall of the elevator shaft 1 1 such that, as the elevator car 12 moves within the elevator shaft 1 1 , the wall passes the ranging sensor 151. That wall may be the wall of the elevator shaft 1 1 which includes the doors 1 1 1.

As will be appreciated, the doors 1 1 1 are not simply flush with the wall of the elevator shaft 1 1 but may include one or more first elements which project into the elevator shaft 1 1 past a plane defined by the wall and/or one or more second elements which are recessed with respect to the plane defined be the wall. The plane of the wall may, therefore, represent a range baseline with variations in range from that baseline indicating the presence of features (such as the first and second elements).

Accordingly, the ranging sensor 151 may be configured to generate ranging data which represents the range of a surface from the ranging sensor 151 and that surface may be formed from multiple different surfaces as the elevator car 12 moves within the elevator shaft 1 1. So, for example, the ranging data may represent a range of the wall from the ranging sensor 151 and may represent a range of one or more first or second elements from the ranging sensor 151 , over time (and, therefore, over a length of the elevator shaft 1 1 ), as the elevator car 12 (and ranging sensor 151 ) move within the elevator shaft 1 1 .

Therefore, as will be appreciated, the ranging data may be generated by the ranging sensor 151 as the elevator car 12 moves within the elevator shaft 1 1 and the ranging data may represent features (such as the first and second elements) which are indicative of the presence of one or more of the doors 1 1 1 .

The processing unit 153 may be configured to receive the ranging data as the elevator car 12 moves within the elevator shaft 1 1 . The processing unit 153 may be configured to recognise, from the ranging data, data representative of the presence of a door 1 1 1. In order to recognise the data representative of the presence of a door 1 1 1 , the processing unit 1531 may use one or more techniques.

The processing unit 1531 may, for example, be configured to determine a change in the range data which exceeds a predetermined threshold (indicating that a surface is closer or further away than the threshold distance). This threshold may be pre-configured. In some embodiments, the threshold is determined in a calibration process. In this calibration process, an average of the range data may be determined and the threshold may be set as a predetermined change from that average (which may be a mean, median, or modal average). The threshold may be adjusted by the processing unit 1531 such that an expected number of doors 1 1 1 is detected using that threshold. In the calibration process, therefore, one or more predetermined movements of the elevator car 12 within the elevator shaft 1 1 may be caused to occur. This may be achieved manually - i.e. by an engineer or user - or may be achieved through a communicative coupling between the processing unit 1531 and the controller 131 , for example. Further details regarding the calibration process options are provided elsewhere herein.

In some embodiments, the processing unit 153 is configured to determine if the predetermined threshold has been exceeded for a predetermined period of time (or over a predetermined distance of travel by the elevator car 12). As will be appreciated, the distance of travel by the elevator car 12 may be determined using the speed data, for example. The time over which a predetermined threshold is exceed is also indicative of the distance travelled by the elevator car 12 whilst the threshold is exceeded and so the size of the surface causing the predetermined threshold to be exceeded. In some embodiments, the speed of the elevator car 12 is measured - as described above - but in some embodiments the processing unit 153 determines the speed data based on assumed characteristics of the elevator system 1. These characteristics may include the average speed of the elevator car 12 in normal operation, and/or the effects on speed during typical deceleration and acceleration of the elevator car 12 during normal operation.

In some embodiments, the processing unit 1531 may be configured to record the ranging data as the elevator car 12 moves within the elevator shaft 1 1 between levels. The processing unit 1531 may be configured to determine one or more a ranging data profiles which are indicative of the presence of a door 1 1 1 . In some embodiments, there is a single ranging data profile which is indicative of the presence of a door 1 1 1 and that profile may be used to determine the presence of a door 1 1 1 from the ranging data irrespective of the identity of the door 1 1 1 - by the processing unit 1531 comparing the ranging data to that profile. In some embodiments, however, there may be more than one ranging data profile and that profile may be specifically associated with a particular door 1 1 1 - such that the presence and identity of the door 1 1 1 may be detected from the ranging data. As will be appreciated, therefore, the processing unit 1531 may be configured to undertake one or more pattern matching processes to match the or each ranging data profile within the ranging data. This or these pattern matching processes may be executed as the ranging data is received by the processing unit 1531.

In some embodiments, the speed data is used in determining the or each ranging data profile - which may be measured speed data or speed data generated by the processing unit 153 as described above using assumed characteristics. The speed data may be used by the processing unit 153 to determine the or each ranging data profile by providing a profile of the changes in range data over a distance or time.

The or each ranging data profile may be a pre-programmed profile or may be generated for a particular elevator car 12 and elevator shaft 1 1 . Much like described above, this may require a calibration process to be executed. In the calibration process one or more predetermined movements of the elevator car 12 within the elevator shaft 1 1 may be caused to occur. This may be achieved manually - i.e. by an engineer or user - or may be achieved through the communicative coupling between the processing unit 153 and the controller 131 . Further details regarding the calibration process options are provided elsewhere herein.

The processing unit 153 may, therefore, be configured to determine from the received ranging data the presence (and in some embodiments the identity) of a door 1 1 1.

In some embodiments, the or each ranging data profile is determined during the calibration process and this process occurs with the elevator system 1 operating at typical speeds. Therefore, in some embodiments, the processing unit 153 may not use the speed data - as this may be substantially common to both the calibration process and normal operation.

In some embodiments, one or more tags with respective predetermined profiles may be provided within the elevator shaft 1 1 (e.g. in association with the doors 1 1 1 ) to aid in identification of the doors 1 1 1 by providing a more recognisable profile. The processing unit 153 may be provided with level information which indicates the number of levels serviced by the elevator car 12 - e.g. the number of levels through which the elevator shaft 1 1 passes and for which doors 1 1 1 are provided. The level information may be stored in the computer readable medium 1531 , for example. The level information may be provided by an engineer, for example, during a configuration process. In some embodiments, the level information is determined by the processing unit 153 during a calibration process - which may be the same as the calibration processes described above or below. This calibration process may include causing a movement of the elevator car 12 through the elevator shaft 1 1 from one extreme position to another (i.e. through all of the levels serviced by the elevator car 12). Further details regarding the calibration process options are provided elsewhere herein.

Accordingly, the processing unit 153 may be configured to count the doors 1 1 1 detected using the ranging data.

The processing unit 153 may be configured to combine a count of the doors 1 1 1 with other information in order to track the movement of the elevator car 12 within the elevator shaft 1 1 and determine the current location of the elevator car 12.

The other information may include, for example, the primary data.

This primary data may include an indication of the direction of travel of the elevator car 12 within the elevator shaft 1 1 as determined from the direction data, for example.

Therefore, the processing unit 153 may be configured to count doors 1 1 1 passed by the elevator car 12 (e.g. as determined from the ranging data) and to combine this with the direction data to maintain an indication of the location of the elevator car 12 within the elevator shaft 1 1 . The air pressure data may be used in a similar manner to provide a direction of travel.

The primary data used by the processing unit 153 may include the air pressure data and may also include the temperature data.

As will be appreciated, the air pressure within the elevator shaft 1 1 at different positions (i.e. at different heights) will vary - with the air pressure typically decreasing the higher the elevator car 12 is located within the elevator shaft 1 1. The rate of change of the air pressure may be indicative of the speed of travel of the elevator car 12.

Accordingly, the processing unit 153 may be configured to compare the air pressure data with a predetermined record of air pressure data and associated elevator car 12 position data. This predetermined data may have been obtained during a calibration process, for example, in which the elevator car 12 was moved between levels within the elevator shaft 1 1 and the air pressure at each level recorded in association with the level at which the elevator car 12 was located.

The air pressure at a particular level may vary from day to day even from hour to hour in the same day. The air pressure at a particular level may vary dependent on, for example, temperature (at least in part). Therefore, the processing unit 153 may be configured to combine the air pressure data and the temperature data to generate normalised air pressure data - in which variations caused by temperature changes are reduced or substantially eliminated.

In some embodiments, this normalised air pressure data may be compared by the processing unit 153 to the predetermined data to provide a location for the elevator car 12. In some embodiments, the predetermined data is adjusted by the processing unit 153 (or some other computing device) using the temperature data and then compared by the processing unit 153 to the air pressure data to provide a location for the elevator car 12.

In some embodiments the predetermined data is associated with a temperature and there are multiple sets of predetermined data associated with different temperatures. As such, the processing unit 153 may use the temperature data to select the set of predetermined data associated with the current temperature (or the closest match thereto) and may be configured to compare the air pressure data with the selected set of predetermined data.

In some embodiments, the processing unit 153 may be configured to use the location of the elevator car 12 as determined using the ranging data with the predetermined air pressure at that location and may then be configured to compare this with the air pressure data to normalise the air pressure data or adjust the predetermined air pressures. This may be performed periodically, for example. In some embodiments, the air pressure data may be used to adjust the predetermined air pressures substantially throughout the operation of the elevator system 1 .

When the elevator car 12 is stationary (or substantially stationary), then the location determined using the air pressure data may be adjusted to the location of the nearest level - based on an understanding that the elevator car 12 is located and stopped at a particular level (rather than between levels). As will be understood, a difference between the location of the nearest level and the location as determined by using the air pressure data may be an error which may be referred to as the adjustment error). This adjusted location and the air pressure data at that location may be used to adjust the predetermined air pressures. This process may be performed each time the elevator car 12 is stopped or substantially stopped, or may be performed at least once in a given period of time (e.g. at least once an hour). This adjustment process may enable the accuracy of the air pressure data determined location of the elevator car 12 to be maintained despite environmental changes during operation of the elevator system 1 . In some embodiments, the predetermined air pressures remain the same as a result of the adjustment process but the locations associated with those locations are adjusted (e.g. upwardly or downwardly by the determined adjustment error).

In some embodiments, as described above, the adjustment process occurs when the elevator car 12 is stationary or substantially stationary - as may be determined by using the primary data, for example (or even by a lack of change in the ranging data, for example).

In some embodiments, the adjustment process may occur when the elevator car 12 is moving. This process may be in addition to or instead of use of the adjustment process when the elevator car 12 is stationary or substantially stationary. In particular, the location of the elevator car 12 may be determined using the ranging data and this location may be compared to the location determined using the air pressure data. This process may be undertaken as the elevator car 12 is moving past levels. This moving adjustment process (in contrast to the above stationary adjustment process) may be useful in instances in which the elevator car 12 is travelling a relatively long distance without stopping, for example.

As will be understood, the adjustment process (moving and/or stationary) may be performed by the processing unit 153. In some embodiments, the adjustment process may be referred to as a refinement process as the location of the elevator car 12 as determined by the air pressure data is refined during the process. Accordingly, the processing unit 153 may be configured to determine a location of the elevator car 12 within the elevator shaft 1 1 using the air pressure data. This may be in addition to a location determined using the ranging data or instead of a location determined using the ranging data.

The processing unit 153 may be configured to determine a location of the elevator car 12 within the elevator shaft 1 1 using more than one method - e.g. using the air pressure data and using the ranging data. Accordingly, the processing unit 153 may be configured to determine more than one indication of the location of the elevator car 12 within the elevator shaft 1 1 .

In some such embodiment, the processing unit 153 may be configured to compare the locations it has determined to generate a confirmed location. A confirmed location may be generated when, for example, the locations match each other. The processing unit 153 may be configured to output the confirmed location as level data (e.g. for use by the controller 131 and/or display on a display device 14).

If the processing unit 153 cannot generate a confirmed location (e.g. because the locations do not match), then the processing unit 153 may output an error without a location indication. In some embodiments, the processing unit 153 may output one of the locations when a confirmed location cannot be generated - which of the locations (i.e. that determined using the ranging data or the air pressure data) is output may be according to a predetermined preference used by the processing unit 153 or may be in accordance with a confidence factor associated with each location. A confidence factor may be determined by the processing unit 153 based on whether the ranging data and/or air pressure data and/or direction data and/or temperature data used to determine each location is within expected ranges (with the confidence factor being greater if the data is within expected ranges and lower if it is outside of expected ranges). In embodiments including the determining of a confidence factor, the confidence factor may be used by the processing unit 153 to select the location determined by the method with the highest associated confidence factor, for example. In embodiments in which only one location is determined (be that using the ranging data or the air pressure data) then that location may be output by the processing unit 153 as the level data.

In some embodiments, the data used to determine the location of the elevator car 12 for output as the level data may be based, at least in part (or entirely), on the determined location, or on the highest or lowest determined location using the ranging data and primary data. In particular, one method may be more reliable above a particular level than another method and this may be used in the selection of which method (and, therefore, which data) to use.

Accordingly, the processing unit 153 is configured to output, as the level data, a location (which may be a confirmed location) of the elevator car 12 within the elevator shaft 1 1 and that location may be used by, for example, the controller 131 and/or one or more display devices 14.

As described herein a calibration process may occur in order to generate predetermined air pressure and/or ranging data for use by the processing unit 153 as described herein. As will be appreciated, the adjustment process may be viewed as a form of operational calibration process - i.e. one which is performed during normal operation of the elevator system 1 (typically without disruption to that normal operation).

The calibration process may be the same or different in relation to the ranging data and the air pressure data.

The calibration process may include one or more predetermined movements of the elevator car 12 within the elevator shaft 1 1 . These one or more movements may be controlled manually by a user sending one or more commands to the controller 131 through the or each interface device 133 and/or using a computing device connected to an interface (such as a maintenance interface) of the controller 131 . The one or more movements may be indicated to the location system 15 (e.g. to the processing unit 153) so that the location system 15 is aware of the location of the elevator car 12 during the calibration process (or during at least part of the calibration process). The indication may be provided by a user inputting the or each movement into the location system 15 using an interface associated therewith - which may be an interface of a computing device connected to the location system 15 during the calibration process, for example.

In some embodiments, the one or more movements are instructed by the location system 15 and may be output onto a display connected to the location system 15 (e.g. a display of a computing device connected to the location system 15 during the calibration process) and then corresponding commands generated by the user as described above. In some embodiments, the one or more movements may be controlled automatically by the location unit 15 - which may be configured, for example, to send one or more commands to the controller 131.

The indication of one or more movements and the instructed movements may be an indication of a level to which the elevator car 12 is to travel (or remain at if the elevator car 12 is already at that level).

The one or more movements may include a movement between the bottom-most and top-most level serviced by the elevator car 12. The one or more movements may include a sequence of movements between the levels services by the elevator car 12.

Accordingly, a calibration process may be used to provide the predetermined information (be it air pressure data, ranging data, or both (and/or temperature data and/or direction data)).

The calibration process may be undertaken when the location system 15 is fitted. The calibration process may be undertaken periodically on a regular or substantially regular schedule (e.g. in accordance with a service schedule for the elevator system 1 ). The calibration process may be undertaken in response to an error (e.g. if a confirmed location cannot be generated).

In some embodiments, the calibration process is undertaken independently for each elevator car 12 in an elevator system 1 . In some embodiments, the calibration process may be undertaken in relation to one elevator car 12 of the elevator system 1 and the predetermined information (as described above) then shared between the location systems 15 associated with each elevator car 12 of the elevator system 1 which service the same levels.

The location system 15 may be powered by an electrical power supply (a main electrical power supply) which may be the same electrical supply which supplies other parts of the elevator system 1 and which may be a mains electrical supply.

In some embodiments, the predetermined information may be stored in the computer readable medium 1531 which may include volatile and/or non-volatile memory.

In some embodiments, the computer readable medium 1531 is provided with auxiliary or backup electrical supply 154 in the form of, for example, a battery 154. The backup electrical supply 154 may be configured to provide electrical power sufficient to maintain the predetermined information stored in the computer readable medium 1531 in the event that the main electrical power supply is interrupted. The backup electrical supply 154 may be configured to provide electrical power sufficient to allow the location system 15 to continue to determine the location of the elevator car 12 until the elevator car 12 has come to a stop in the event that the main electrical power supply is interrupted. The backup electrical supply 154 may be configured to provide electrical power for a predetermined minimum period of time, such as 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, or 6 hours (or 12 hours, or 24 hours, for example).

The operation of the location system 15 after the main electrical power supply is interrupted may be useful as the elevator car 12 may continue to travel due to its momentum after the main electrical power supply is interrupted and before the elevator car 12 comes to a stop.

The computer readable medium 1531 may be configured to store the location or confirmed location (i.e. the level data for the current position of the elevator car 12).

In some embodiments, the backup electrical supply 154 is configured to provide power in this manner to the location system 15 as a whole or, at least, to the processing unit 153.

In some embodiments, the location system 15 includes the backup electrical supply 154. In some embodiments, the location system 15 is configured to determine when the main electrical power supply has been interrupted.

In some embodiments, the location system 15 may be configured to provide the location or confirmed location (i.e. the level data) to the controller 131 and/or display device(s) 133 when the main electrical power supply is returned. This transmission of the location or confirmed location may be in response to the main electrical power supply returning or in response to a request made by the controller 131 (or display device(s) 133) or in response to detecting (by the location system 15) that the controller 131 (or display device(s) 133) has completed a start-up sequence (e.g. a boot-up sequence). In some embodiments, the location or confirmed location (i.e. the level data) may also or alternatively be provided to a display device 14 which is provided for a maintenance user (as opposed to, for example, display devices 14 which are used primarily for information for the users wishing to travel in or actually travelling in the elevator car 12). This may enable a maintenance user to use this information when resetting the elevator system 1 when the main power supply is returned. This display device 14 may, therefore, be referred to as a maintenance display device.

In some embodiments, the location system 15 is configured to output the level data (i.e. the location or confirmed location) to a remote device. This may be achieved by using an interface of the location system 15 which is configured to communicate with a network - which may include a wireless network and/or a wired network. In some embodiments, the wireless network may include a cellular telephone network, for example. In some embodiments, the location system 15 is configured to output the level data to the remote device on receipt of a request from the remote device or, for example, on the identification of a problem with the elevator system 1. This problem may include, for example, a detected failure of part of the elevator system 1 which may be reported to the location system 15 from another part of the elevator system 1 (or an operator/user reporting the failure) or which may be determined by the location system 15 due to determined location of the elevator car 12 (e.g. the car 12 being located between levels and stationary). Accordingly, the level data may be sent to a service company so that an engineer can travel to the site at which the elevator system 1 is located to perform maintenance, with the service company knowing from the level data the location of the elevator car 12. In some instances, the location system 15 is configured to output the level data to the remote device when a main power failure is detected and/or when the main power is restored.

Therefore, as will be understood, embodiments seek to provide a system 15 which uses one or more of range data and primary data to determine the location of the elevator car 12 within the elevator shaft 1 1. This may be achieved by effectively counting the passing of doors 1 1 1 represented by the ranging data and/or through the variations in air pressure as the elevator car 12 moves within the elevator shaft 1 1.

This current location may be output as the level data by the location system 15 (e.g. by processing unit 153) for use by other parts of the elevator system 1 - i.e. for use in monitoring and/or control of the operation of the elevator system 1.

The primary data may provide directional of travel information as described above or may provide location information. The location system 15 may be configured to seek to provide the most reliable level data using the available ranging and/or primary data. The location system 15 may be configured to disregard or discard locations which are determined using data which appears to be abnormal (i.e. outside of expected ranges).

The location system 15 may be configured to run calibration processes periodically and some calibration processes may be operated automatically or during the normal operation of the elevator system 1.

In some embodiments, the or each ranging data profile may form an internal map of the elevator shaft 1 1 . This map may comprise variations in range of surfaces within the field of view of the ranging sensor 151 (which may be a relatively thin strip extending along a length of the elevator shaft 1 1 ). The ranging data profile may be stored on the computer readable medium 1531 and may form a product of the operation of the location system 15. The same is also true for the air pressure data which may form an air pressure profile for the elevator car 12 within the elevator shaft 1 1 (the air pressure profile including predetermined air pressures at different locations within the elevator shaft 12). In some embodiments, therefore, there is a method of generating a ranging data profile and/or an air pressure profile which comprising recording the ranging data and/or air pressure during a calibration process as described herein.

As will be appreciate, the air pressure profile may vary due to characteristics of the elevator shaft 1 1 and the movement of the elevator car 12 within the shaft 1 1. In some embodiments, more than one air pressure profile may be provided with each air pressure profile being dependent on a speed of the elevator car 12 within the shaft 1 1 , for example. The processing unit 153 may be configured to select the air pressure profile (i.e. the set of one or more predetermined air pressures) based at least in part on the speed of the elevator car 12 (e.g. as provided by virtue of the speed data).

The adjustment or calibration process may result in a change to the air pressure profile which may include the adjustment of one or more predetermined pressures and/or the associated locations.

Whilst embodiments have been described with reference to the identification of doors 1 1 1 within the ranging data, this is one example of a recognisable element (another being the aforementioned tags). Other forms of recognisable element (which may be some other internal feature of a particular elevator shaft 1 1 may also be used, such as air ducts and the like).

As will be understood, the level data provides a location of the elevator car 12 within the elevator shaft 1 1. The form and accuracy of that location may vary depending on how that location is determined. For example, the location determined by the ranging data may be to the nearest level in some embodiments; however, the location determined by the air pressure data may be of a finer resolution and could include, for example, an inter-level location (i.e. a location between levels). In some embodiments, the location determined using the air pressure data is a substantially continuous location measurement (as opposed to the discrete location measurement of the nearest level) based on a predetermined reference location - e.g. the bottom or top position of the elevator car 12 within the elevator shaft 12. Therefore, in some embodiments, the location determined using the air pressure data may be a distance measurement, whereas the location determined using the ranging data may be a level indication.

In some embodiments, therefore, the location determined by use of the ranging data is used in the adjustment process in relation to the location determined by the air pressure data. The level data may, therefore, be based on the location determined using the air pressure data (as adjusted using, for example, the location determined using the ranging data).

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1 . A location system for use in an elevator system, the location system including:

a ranging sensor carried by an elevator car of the elevator system, directed toward a sidewall of an elevator shaft of the elevator system, and configured to generate ranging data; and

a processing unit configured to:

receive the ranging data;

identify one or more recognisable elements within the ranging data indicative of the location of the elevator car; and

determine the location of the elevator car based on the or each identified recognisable element.

2. A location system according to claim 1 , wherein the ranging sensor is a LiDAR sensor.

3. A location system according to claim 1 , wherein the ranging sensor is an acoustic sensor.

4. A location system according to any preceding claim, wherein the processing unit is configured to identify one or more recognisable elements within the ranging data by comparing the ranging data to a threshold.

5. A location system according to any of claims 1 to 3, wherein the processing unit is configured to identify one or more recognisable elements within the ranging data using one or more stored range data profiles.

6. A location system according to any preceding claim, further including a primary sensor configured to determine a direction of travel of the elevator car, wherein the processing unit is further configured to use the or each identified recognisable elements and the direction of travel to determine a location of the elevator car within the elevator shaft.

7. A location system according to claim 6, wherein the primary sensor includes an air pressure sensor.

8. A location system according to claim 7, wherein the processing unit is configured to use air pressure data generated by the primary sensor to determine a direction of travel of the elevator car within the elevator shaft.

9. A location system according to claim 6, wherein the air pressure sensor is configured to generate air pressure data and the processing unit is configured to determine a location of the elevator car using the air pressure data.

10. A location system according to claim 9, wherein the processing unit is configured to compare the air pressure data to a predetermined air pressure profile to determine the location of the elevator car.

1 1. A location system according to claim 10, wherein the processing unit is configured to compare the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and to determine a confirmed location based on the comparison.

12. A location system according to claim 10, wherein the processing unit is configured to compare the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and to adjust the predetermined air pressure profile based on the comparison.

13. A location system according to any preceding claim, wherein the processing unit is configured to output the determined location as level data to one or more of a controller of the elevator system and a display device, the controller being configured to control movement of the elevator car within the elevator shaft and the display device configured to display a current location of the elevator car.

14. A location system according to any preceding claim, further including a backup electrical supply which is configured to provide power to the location system after a main power failure such that the location system is configured to determine a location of the elevator car after the main power failure.

15. An elevator system including a location system according to any preceding claim.

16. A method of determining the location of the elevator car for use in an elevator system, the method including:

receiving ranging data generated using a ranging sensor carried by an elevator car of the elevator system, directed towards a sidewall of an elevator shaft of the elevator system; identifying, using a processing unit, one or more recognisable elements within the ranging data indicative of the location of the elevator car; and

determining, using a processing unit, the location of the elevator car based on the or each identified recognisable element.

17. A method according to claim 16, wherein the ranging sensor is a LiDAR sensor.

18. A method according to claim 16, wherein the ranging sensor is an acoustic sensor.

19. A method according to any of claims 16 to 18, wherein identifying one or more recognisable elements within the ranging data includes comparing the ranging data to a threshold.

20. A method according to any of claims 16 to 18, wherein identifying one or more recognisable elements within the ranging data includes using one or more stored range data profiles.

21. A method according to any of claims 16 to 20, further including: determining a direction of travel of the elevator car, using a primary sensor; and using, by a processing unit, of the or each identified recognisable elements and the direction of travel to determine a location of the elevator car within the elevator shaft.

22. A method according to claim 21 , wherein the primary sensor includes an air pressure sensor.

23. A method to claim 22, further comprising using air pressure data, by a processing unit, generated by the primary sensor to determine a direction of travel of the elevator car within the elevator shaft.

24. A method according to claim 22, wherein the air pressure sensor is configured to generate air pressure data and the method further includes determining, using a processing unit, a location of the elevator car using the air pressure data.

25. A method according to claim 24, further including comparing, using a processing unit, the air pressure data to a predetermined air pressure profile to determine the location of the elevator car.

26. A method according to claim 25, further including comparing, using a processing unit, the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and determining, using a processing unit, a confirmed location based on the comparison.

27. A method according to claim 25, further including comparing, using the processing unit, the location of the elevator car determined using the ranging data with the location of the elevator car determined using the air pressure data, and adjusting the predetermined air pressure profile based on the comparison.

28. A method according to any of claims 16 to 27, further including outputting, from a processing unit, the determined location as level data to one or more of a controller of the elevator system and a display device, the controller being configured to control movement of the elevator car within the elevator shaft and the display device configured to display a current location of the elevator car.

29. A method according to any of claims 16 to 28, further including providing power to the location system, using a backup electrical supply, after a main power failure, and determining a location of the elevator car after the main power failure.

30. A calibration process for a location system according to any of claims 1 to 15, the method including:

controlling the elevator car to perform one or more predetermined movements within the elevator shaft; and

recording the ranging data using the ranging sensor during the one or more predetermined movements to generate a ranging data profile.