Method and arrangement for determining location and/or speed of a moving object and use of the arrangement

Patent metadata

Field	Value
Publication number	US-9958250-B2
Application number	US-201414319944-A
Country	US
Kind code	B2
Filing date	Jun 30, 2014
Priority date	Dec 30, 2011
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A method and an arrangement is provided for determining the location and/or speed of an object configured to move along a controlled trajectory, in connection with which object is fitted a measuring device measuring at least the magnetic field acting on the object in its different locations, which measuring device comprises a device configured to measure the magnetic field, from the measuring data received from which device a magnetic footprint describing the magnetic field acting on the object in its different locations is formed, which magnetic footprint is recorded in connection with a teaching run, or with self-learning, for later use. The location of the object after a teaching run is determined by measuring in essentially real-time in the direction of the three coordinates X, Y, Z of the magnetic field acting on the object moving along a controlled trajectory and by comparing the measurement results to a magnetic footprint recorded in advance and also by deducing as a result of the comparison the exact location of the object on its path of travel.

First claim

The invention claimed is:

1. A method for determining a location and/or speed of an object configured to move along essentially a same controlled trajectory in a magnetic field deflected by a static and/or dynamic change, the method comprising the steps of:
a measuring device measuring at least the magnetic field acting on the object in its different locations, the measuring device being fitted in connection with the object, and comprising at least means for measuring the magnetic field; and
forming a magnetic footprint describing the magnetic field acting on the object in its different locations from measuring data received from the measuring device;
recording the magnetic footprint in a memory of an arrangement for later use before actual operation of the object,
wherein
before actual operation or during operation an initialization is performed, wherein the object is moved on the controlled trajectory, and at points determined by either position and/or time on the controlled trajectory the magnetic field acting on the object is measured with the means for measuring a magnetic field and the measurement results obtained are recorded as magnetic footprints in the memory of the arrangement,
in addition to measuring the magnetic field, additional measuring means at essential points of the controlled trajectory from viewpoint of the operation of the object are optionally used as an aid for measuring other sensor data of the object in its environment at that moment and/or the time used data, and measurement results obtained from measuring the other sensor data are recorded in the memory of the arrangement,
from the measurement results obtained at the aforementioned points determined by either position and/or time on the controlled trajectory, position data of the object in relation to the controlled trajectory and optionally time data to be connected to the position data are formed by fixing the measurement results to the determined measuring locations of the controlled trajectory, and
during operation, the movement and environment of the object is measured with the same means for measuring a magnetic field as during the initialization, and optionally with the same additional measuring means as during the initialization, and the measurement results obtained are compared to optimal sensor data formed from the measurement results recorded in the memory of the arrangement during the initialization and recorded in the memory, as well as to measured data about the environmental conditions of the object, and
wherein the method further comprises determining locations of the object during the operation and detecting changes occurring in the operation in relation to location, motion state and condition of the object by comparing real-time measurement results obtained during operation of the object to the optimal sensor data formed from the measurement results recorded in the memory during the initialization.

2. The method according to claim 1 , wherein after learning, self-adjustment, the use of an external model, initialization or a corresponding function, at least the location of the object is determined by measuring with the means for measuring a magnetic field, in the direction of the three coordinates X, Y, Z and in essentially real-time, the magnetic field, deflected by a static and dynamic change caused by the environment of the object and by the object itself acting on the object moving along a controlled trajectory, and by comparing the measurement results to a magnetic footprint measured on the aforementioned controlled trajectory with the same means for measuring a magnetic field and recorded in advance in the memory, and also by deducing as a result of the comparison the location of the object on its controlled path of travel.

3. The method according to claim 1 , wherein from the aforementioned magnetic footprints a three-dimensional magnetic map is formed, from which a four-dimensional magnetic map is further formed by combining the footprints measured at each position of the controlled path of travel and the time dimension with each other.

4. The method according to claim 1 , wherein in connection with learning or initialization and in connection with operation of the object, the magnetic footprint to be measured in the direction of the three coordinates X, Y, Z is measured from the magnetic field of the earth modified by the immediate surroundings of the object and by the structures characteristic to the object itself without the use of separate position sensors or sensors intended for determining the location.

5. The method according to claim 1 , wherein used for determining the location of the object, in addition to and/or as an aid to the measurement of the magnetic field, are a measurement of acceleration, which is performed with a device for measuring acceleration, which device is configured for moving along with the moving object and which is configured to give the direction information of the moving object to the measuring device, and/or a gyroscope, which is configured for moving along with the moving object and which is configured to give rotation direction of the moving object to the measuring device, and/or a pressure sensor, which is configured for moving along with the moving object and which is configured to give information about the pressure exerted in the environment of the moving object to the measuring device, and/or a machine vision arrangement, which for its part is configured for moving along with the moving object and which is configured to give visual information about the environment of the moving object to the measuring device.

6. The method according to claim 5 , wherein the measured values of the magnetic fields measured with the means for measuring a magnetic field, measured values of acceleration and/or deceleration measured with the device for measuring acceleration, and image information obtained by the aid of a camera are recorded either in the own memory of the measuring device or in a memory of a control system of the object.

7. The method according to claim 1 , wherein a gyroscope is used for producing information for the measuring device relating to the orientation and rotation direction of an object moving along a controlled trajectory, and a pressure sensor is used for producing information for the measuring device relating to the compression data acting on an object moving along a controlled trajectory or relating to the height position of the object, and other additional measuring means are used for producing information for the measuring device relating to the conditions of the environment of an object moving along a controlled trajectory.

8. The method according to claim 1 , wherein a video signal or image signal is used in addition to and/or as an aid to the measurement of the magnetic field for determining the location of the object, which signal is produced with a camera configured for moving along with the moving object, which camera is configured to give to the measuring device status information about the structures of the object or information about the environment of the object.

9. The method according to claim 1 , wherein at least the means for measuring a magnetic field are fitted on an elevator car and with the aforementioned means for measuring a magnetic field the characteristically determined magnetic field in relation to the own structures of the building and the structures of the elevator acting on the elevator car at the different locations of the path of travel of the elevator car is measured.

10. The method according to claim 9 , wherein, in addition to and/or as an aid to the measurement of the magnetic field, for determining the location of an elevator car a measurem

Assignees

• Kone Corp

Inventors

• Reilio Esa
• Kulju Hannu
• Korkalo Otto
• Kantonen Tuomas

Classifications

• G01B7/004 Primary

  for measuring coordinates of points · CPC title

• G01P3/42

  Devices characterised by the use of electric or magnetic means (G01P3/66 takes precedence; measuring electric or magnetic values in general G01R) · CPC title

• B66B1/3492 Primary

  Position or motion detectors or driving means for the detector (B66B1/40, B66B1/50 take precedence; length measuring G01B; speed measuring G01P) · CPC title

• B66B19/007

  method for modernisation of elevators · CPC title

• G01P3/50

  for measuring linear speed (G01P3/56 takes precedence) · CPC title