COMPUTER-IMPLEMENTED METHOD OF MONITORING THE OPERATION OF A CARGO SHIPPING REEFER CONTAINER

• US 20160216028A1
• Filed: 08/29/2013
• Published: 07/28/2016
• Est. Priority Date: 08/29/2013
• Status: Active Grant

• Current Assignee: Maersk Line A/S (A.P. Møller Holding A/S)
• Original Assignee: A.P. Moller-Maersk A/S (A.P. Møller Holding A/S)
• Inventors: JNSSON, Ragnar Ingi, SKOVRUP, Morten Juel, GRANLUND, Rabia Line Bonding, SEURIN, Thierry, ERIKSEN, Rasmus Solmer, BAERENTZ, Morten Rene
• Granted Patent: US 10,451,341 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B65D 88/745 blowing or injecting heating, cooling or other conditioning fluid inside the container
• CPC Class Codes: F25D 11/003 Transport containers
• CPC Class Codes: F25D 2500/04 Calculation of parameters
• CPC Class Codes: F25D 29/003 for movable devices
• CPC Class Codes: F25D 29/008 Alarm devices
• CPC Class Codes: G05B 17/02 electric

Abstract

Techniques for remotely monitoring the operation of a cargo shipping reefer container configured with a refrigeration system that has installed therewith a control computer coupled with sensors monitoring the operation of the refrigeration system include: collecting a first and second set of observation data comprising a respective first and second sequence of measurement values measured by sensors coupled to the control computer; running a simulation model that receives the first set of observation data as input and outputs simulated values; the simulation model is configured to output the simulated values as estimates of the second set of the observations; computing an indicator value as a function of residual values computed from the difference between the values of the second set of observations and the simulated values; and evaluating the indicator value against a predefined criterion and issuing an alarm signal in case the predefined criterion is exceeded.

Claims

1. A computer-implemented method of remotely monitoring the operation of a cargo shipping reefer container configured with a refrigeration system that has installed therewith a control computer coupled with sensors monitoring the operation of the refrigeration system;

the method comprises;

collecting, from the control computer, a first set of observation data and a second set of observation data comprising a respective first and second sequence of measurement values measured by sensors coupled to the control computer;

collecting preset values, from a database, that define settings for a cargo property value that defines thermo-dynamic properties of the cargo,

running a simulation model that receives the first set of observation data and the preset values as input and outputs simulated values;

wherein the simulation model is configured to output the simulated values as estimates of the second set of the observation data;

computing an indicator value as a function of residual values computed from the difference between the values of the second set of observation data and the simulated values;

evaluating the indicator value against a predefined criterion and issuing an alarm signal in case the predefined criterion is exceeded.

2. A method according to claim 1, wherein computing of the indicator value comprises computing a cumulative value of the residuals.

3. A method according to claim 1, wherein the preset values further defines settings for at least one of the refrigeration system of the reefer container and features of the reefer container and cargo property values.

4. A method according to claim 3, wherein the preset values that are input to the simulation model further comprise:

a preset temperature value that defines a temperature the refrigeration system is set to obtain for the cargo; and

a cargo property value that defines thermo-dynamic properties of the cargo.

5. A method according to claim 1,

wherein the first set of observation data that is collected from the control computer and input to the simulation model comprises at least one of:

a measured temperature value that is an estimate of an ambient temperature for the cargo shipping reefer container; and

a measured volume that is an estimate of the volume of fresh air intake for the cargo shipping reefer container.

6. A method according to claim 1, wherein the second set of observation data that is collected from the control computer and compared to output of the simulation model comprises:

a first temperature value and a second temperature value that are measured in an air flow flowing through an evaporator of the refrigeration system.

7. A method according to claim 1, wherein the second set of observation data that is collected from the control computer and compared to output of the simulation model comprises:

a first pressure value and a second pressure value that are measured with respect to a compressor in the refrigeration system.

8. A method according to claim 1, comprising:

performing a smoothening filter operation on the first sequence of measurement values prior to being input for the simulation model.

9. A method according to claim 1, comprising:

processing a sequence of measurement values to estimate at least one of a level of the measurement values and a change in level;

comparing the at least one estimated level and change in level to a predetermined criterion; and

issuing an alarm signal in case the predefined criterion is exceeded.

10. A method according to claim 1, wherein the simulation model has a first mode, which is a default mode and a second selectable mode, comprising:

processing a sequence of measurement values to estimate a level of the measurement values and/or a change in level;

comparing the estimated level and/or change in level to a predetermined criterion; and

selecting the second mode when the predefined criterion is exceeded.

11. A method according to claim 1, comprising:

preparing the simulation model for an ensuing period of simulation in response to detection of an ensuing trip of the reefer container;

wherein an ensuing trip of the reefer container is detected as a pause of a predetermined length within which observation data from the respective reefer container has not been received followed by further observation data.

12. A method according to claim 1, comprising:

processing a sequence of measurement values to estimate a level of the measurement values and/or a change in level;

comparing the estimated level and/or change in level to a predetermined criterion; and

disabling issuing of the alarm signal while the predetermined criterion is exceeded.

13. A method according to claim 1, comprising:

receiving a sign-in signal, from the control computer, indicating that the cargo shipping reefer container signs in to a fault monitoring program,

receiving a sign-out signal, from the control computer, indicating that the cargo shipping reefer container signs out from the fault monitoring program.

14. A method according to claim 1, wherein the steps of collecting observation data, running the simulation model, computing a cumulative value and evaluating the cumulative value are performed on a container monitoring system;

and wherein preset values for a specific journey are stored in a container booking system and transmitted to the container monitoring system.

15. A method according to claim 1,

wherein a communications station communicates over a first wireless network with the control computer to receive the first and second set of observations;

wherein the communications station communicates with a server computer over a second wireless network to transmit the first and second set of observations to the server computer; and

wherein the running of the simulation model, the computing of residual values and the evaluation of the residual values is performed on the server computer.

16. A method according to claim 15, wherein the alarm signal is reported via the communications station.

17. A method according to claim 1, wherein multiple instances of a simulation model for respective cargo shipping containers are run on a server computer.

18. A system comprising a server computer configured to perform the method of claim 1.

19. A computer-readable medium encoded with a program to perform the method of claim 1 when run on a computer system.