Method for monitoring lifting events at a construction site

1. A system comprising:

a crane shackle configured to transiently install on a crane hook of a crane;

a lifting hook arranged below the crane hook and configured to couple to a load;

a body interposed between the crane shackle and the lifting hook;

a load sensor coupled to the body and configured to output load values representing a tensile force between the crane shackle and the lifting hook;

a wireless communication module; and

a controller configured to:

access a first timeseries of load values output by the load sensor during loading of an object onto the lifting hook within a first time period;

derive a lifting profile of the object from the first timeseries of load values;

identify a type of the object based on the lifting profile; and

transmit the type of the object, carried by the lifting hook during the first time period, to a remote computer system via the wireless communication module.

2. The system of claim 1 :

further comprising a geospatial position module coupled to the body and configured to output geospatial locations of the body; and

wherein the controller is configured to:

read a first geospatial location from the geospatial position module during loading of the object onto the crane hook within the first time period;

read a second geospatial location from the geospatial position module during unloading of the object from the crane hook within the first time period;

generate a lift event record defining the type of the object, a pickup location of the object at the first geospatial location, and a drop-off location of the object at the second geospatial location; and

transmit the lift event record to the remote computer system via the wireless communication module.

3. The system of claim 2 :

further comprising an altimeter coupled to the body and configured to output altitude values representative of the altitude of the body; and

wherein the controller is configured to:

access a second timeseries of geospatial locations output by the geospatial position module during the first time period;

access a third timeseries of altitude values output by the altimeter during the first time period;

interpret a path of the object during the first time period based on the second timeseries of geospatial locations and the third timeseries of altitude values; and

generate the lift event record further comprising the path of the object.

4. The system of claim 2 , wherein the controller is configured to:

record the first geospatial location in response to detecting an increase in load carried by the lifting hook at a first time based on the first timeseries of load values;

detect a peak load, in the first timeseries of load values, at a second time succeeding the first time;

store the peak load as a first weight of the object;

derive the lifting profile from a first subset of the first timeseries of load values output by the load sensor between the first time and the second time;

detect a decrease in load carried by the lifting hook at a third time succeeding the second time based on the first timeseries of load values;

detect unloading of the object from the lifting hook at a fourth time succeeding the third time based on the first timeseries of load values; and

record the second geospatial location between the third time and the fourth time.

5. The system of claim 4 , wherein the controller is configured to:

derive an unloading profile from a second subset of the first timeseries of load values output by the load sensor between the third time and the fourth time; and

verify the type of the object based on the unloading profile.

6. The system of claim 1 :

further comprising a motion sensor coupled to the body and configured to output signals representing motion of the body; and

wherein the controller is configured to:

access a second timeseries of motion values output by the motion sensor following loading of the object onto the lifting hook within the first time period;

derive an oscillation characteristic from the second timeseries of motion values; and

identify the type of the object further based on the oscillation characteristic.

7. The system of claim 6 , wherein the controller is configured to:

derive, from the first timeseries of load values, the lifting profile representing transition of weight of the object onto the lifting hook over a loading duration within the first time period; and

derive, from the second timeseries of motion values, the oscillation characteristic representing swinging of the object over a transfer duration following the loading duration within the first time period.

8. The system of claim 7 , wherein the controller is configured to:

derive, from the second timeseries of motion values, the oscillation characteristic comprising a pitch frequency of the object; and

identify the type of the object as a concrete hopper based on:

the first loading duration falling within a template range of loading durations associated with concrete hoppers; and

the pitch frequency falling within a template range of sloshing frequencies associated with concrete hoppers.

9. The system of claim 1 , wherein the controller is configured to:

detect an increase in load carried by the lifting hook at a first time based on the first timeseries of load values;

detect a peak load, in the first timeseries of load values, at a second time succeeding the first time;

derive the lifting profile from a first subset of the first timeseries of load values output by the load sensor between the first time and the second time;

detect a decrease in load carried by the lifting hook at a third time succeeding the second time based on the first timeseries of load values;

detect unloading of the object from the lifting hook at a fourth time succeeding the third time based on the first timeseries of load values;

derive an unloading profile from a second subset of the first timeseries of load values output by the load sensor between the third time and the fourth time; and

verify the type of the object based on the unloading profile.

10. The system of claim 9 , wherein the controller is configured to:

calculate a set of lifting similarity scores for the object, each lifting similarity score in the set of lifting similarity scores representing similarity between the lifting profile and a template lifting profile of an object type in a set of object types;

calculate a set of unloading similarity scores for the object, each unloading similarity score in the set of unloading similarity scores representing similarity between the unloading profile and a template unloading profile of an object type in the set of object types;

calculate a set of load similarity scores for the object, each load similarity score in the set of load similarity scores representing proximity of the first weight of the object to a load range of an object type in the set of object types; and

verify the type of the object based on a combination of the set of lifting similarity scores, the set of unloading similarity scores, and the set of load similarity scores.

11. The system of claim 1 , wherein the controller is configured to:

access a set of notification triggers associated with a construction site; and

in response to a notification trigger, in the set of notification triggers, specify loading of the type of the object onto the crane hook:

generating a notification specifying loading of the type of the object; and

during the first time period, transmitting the notification to the remote computer system via the wireless communication module.

12. The system of claim 1 , wherein the controller is configured to:

during the first time period while the crane shackle is installed on the crane hook of the crane at a first construction site:

access the first timeseries of load values output by the load sensor within the first time period; and

transmit the type of the object, carried by the lifting hook, to the remote computer system at the first construction site via the wireless communication module; and

during a second time period succeeding the first time period while the crane shackle is installed on a second crane hook of a second crane at a second construction site:

access a second timeseries of load values output by the load sensor during loading of a second object onto the lifting hook;

derive a second lifting profile of the second object from the second timeseries of load values;

identify a second type of the second object based on the second lifting profile; and

transmit the second type of the second object, carried by the lifting hook during the second time period, to a second remote computer system at the second construction site via the wireless communication module.

13. The system of claim 1 , wherein the controller is configured to:

identify initial coupling of the object to the lifting hook at a first time in response to a first load value, represented in the first timeseries of load values, exceeding a threshold load value;

detect a peak load, in the first timeseries of load values, at a second time succeeding the first time;

derive, from the first timeseries of load values, the lifting profile representing loading of the crane hook, via the lifting hook, as a function of time from the first time to the second time;

characterize a slope of the lifting profile;

calculate an oscillation characteristic of the lifting profile; and

identify the type of the object based on the slope of the lifting profile and the oscillation characteristic of the lifting profile.

14. A system comprising:

a crane shackle configured to transiently install on a crane hook of a crane;

a lifting hook arranged below the crane hook and configured to couple to a load;

a body interposed between the crane shackle and the lifting hook;

a motion sensor coupled to the body and configured to output motion values representing motion of the body;

a wireless communication module; and

a controller configured to:

access a first timeseries of motion values output by the motion sensor following loading of an object onto the lifting hook within a first time period;

derive an oscillation characteristic of the object from the first timeseries of motion values;

identify a type of the object based on the oscillation characteristic; and

transmit the type of the object, carried by the lifting hook during the first time period, to a remote computer system via the wireless communication module.

15. The system of claim 14 :

further comprising a load sensor coupled to the body and configured to output load values representing a tensile force between the crane shackle and the lifting hook;

wherein the controller is configured to:

access a second timeseries of load values output by the load sensor during loading of the object onto the lifting hook within the first time period;

derive a lifting profile of the object from the first timeseries of load values;

identify the type of the object further based on the lifting profile.

16. The system of claim 14 :

further comprising a load sensor coupled to the body and configured to output load values representing a tensile force between the crane shackle and the lifting hook; and

wherein the controller is configured to:

derive, from the first timeseries of load values, the oscillation characteristic comprising a pitch frequency of the object;

access a second timeseries of load values output by the load sensor during the first time period;

derive a natural frequency of the object from the second timeseries of load values;

identify the object as elongated in response to the pitch frequency falling below a threshold frequency; and

in response to identifying the object as elongated:

identify the object as rebar in response to the natural frequency falling below a threshold frequency; and

identify the object as a steel beam in response to the natural frequency exceeding the threshold frequency.

17. The system of claim 1 :

further comprising a geospatial position module coupled to the body and configured to output geospatial locations of the body; and

wherein the controller is configured to:

read a first geospatial location from the geospatial position module during loading of the object onto the crane hook within the first time period;

read a second geospatial location from the geospatial position module during unloading of the object from the crane hook within the first time period;

generate a lift event record defining the type of the object, a pickup location of the object at the first geospatial location, and a drop-off location of the object at the second geospatial location; and

transmit the lift event record to the remote computer system via the wireless communication module.

18. The system of claim 17 :

further comprising a load sensor coupled to the body and configured to output load values representing a tensile force between the crane shackle and the lifting hook; and

wherein the controller is configured to:

access a second timeseries of load values output by the load sensor during the first time period;

detect a peak load, in the first timeseries of load values, at a second time succeeding the first time;

detect a decrease in load carried by the lifting hook at a third time succeeding the second time based on the first timeseries of load values; and

derive the oscillation characteristic of the object from a first subset of the first timeseries of load values output by the motion sensor between the second time and the third time.

19. The system of claim 14 :

further comprising a camera coupled to the body and facing downward toward the lifting hook; and

wherein the controller is configured to:

access an image captured by the camera during the first time period;

detect the object in a region of the image frame;

label the region of the image with the type of the object; and

transmit the image to the remote computer system via the wireless communication module.

20. The system of claim 14 , wherein the controller is configured to:

during the first time period while the crane shackle is installed on the crane hook of the crane at a first construction site:

access the first timeseries of motion values output by the motion sensor within the first time period; and

transmit the type of the object, carried by the lifting hook, to the remote computer system at the first construction site via the wireless communication module; and

during a second time period succeeding the first time period while the crane shackle is installed on a second crane hook of a second crane at a second construction site:

access a second timeseries of motion values output by the motion sensor following loading of a second object onto the lifting hook;

derive a second oscillation characteristic of the second object from the second timeseries of motion values;

identify a second type of the second object based on the second oscillation characteristic; and

transmit the second type of the second object, carried by the lifting hook during the second time period, to a second remote computer system at the second construction site via the wireless communication module.