SAFE OPERATION OF MACHINERY USING POTENTIAL OCCUPANCY ENVELOPES
Various embodiments for enforcing safe operation of machinery performing an activity in a three-dimensional (3D) workspace includes computationally generating a 3D spatial representation of the workspace; computationally mapping 3D regions of the workspace corresponding to space occupied by the machinery and a human; and based thereon, restricting operation of the machinery in accordance with a safety protocol during physical performance of the activity.
1 . A safety system for enforcing safe operation of machinery performing an activity in a three-dimensional (3D) workspace, the system comprising:
a computer memory for storing (i) a model of the machinery and its permitted movements and (ii) a safety protocol specifying speed restrictions of the machinery in proximity to a human and a minimum separation distance between the machinery and a human; and
a processor configured to:
computationally generate, from the stored images, a 3D spatial representation of the workspace;
map, via a mapping module, a first 3D region of the workspace corresponding to space occupied by the machinery within the workspace augmented by a 3D envelope around the machinery spanning all movements executed by the machinery during performance of the activity; and
identify a second 3D region of the workspace corresponding to space occupied or potentially occupied by a human within the workspace augmented by a 3D envelope around the human corresponding to anticipated movements of the human within the workspace during the interval, wherein:
(i) the computer memory further stores a geometric representation of a restriction zone within the first 3D region of the workspace; and
(ii) the processor is configured to, during physical performance of the activity, restrict operation of the machinery (a) in accordance with a safety protocol based on proximity between the first and second regions and (b) to remain within or outside the restriction zone.
2 . The safety system of claim 1 , wherein the processor is configured to identify a pose and trajectory of the machinery based at least in part on state data provided by the machinery.
3 . The safety system of claim 2 , wherein the state data is safety-rated and is provided over a safety-rated communication protocol.
4 . The safety system of claim 3 , wherein the state data is not safety-rated but is validated by information received from a plurality of sensors.
5 . The safety system of claim 1 , further comprising a control system, executable by the processor, having safety-rated and non-safety-rated components, restriction of the operation of the machinery to remain within or outside the restriction zone being performed by the safety-rated component.
6 . The safety system of claim 1 , wherein the restriction zone is a keep-out zone and the mapping module is further configured to determine a path along which the machinery can perform the activity without entering the keep-out zone.
7 . The safety system of claim 1 , wherein the restriction zone is a keep-in zone and the mapping module is further configured to determine a path along which the machinery can perform the activity without leaving the keep-in zone.
8 . The safety system of claim 1 , wherein the safety protocol specifies a protective separation distance as a minimum distance separating the machinery from the human.
9 . The safety system of claim 8 , wherein the processor is configured to, during physical performance of the activity, continuously compare an instantaneous measured distance between the machinery and the human to the protective separation distance and adjust an operating speed of the machinery based at least in part on the comparison.
10 . The safety system of claim 8 , wherein the processor is configured to, during physical performance of the activity, govern an operating speed of the machinery to a set point at a distance larger than the protective separation distance.
11 . The safety system of claim 10 , further comprising a control system, executable by the processor, having safety-rated and non-safety-rated components, the operating speed of the machinery being governed by the non-safety-rated component.
12 . The safety system of claim 1 , wherein the first 3D region is divided into a plurality of nested, spatially distinct 3D subzones.
13 . The safety system of claim 12 , wherein overlap between the second 3D region and each of the subzones results in a different degree of alteration of the operation of the machinery.
14 . The safety system of claim 1 , wherein the processor is further configured to recognize a workpiece being handled by the machinery and treat the workpiece as a portion thereof in identifying the first 3D region.
15 . A method of enforcing safe operation of machinery performing an activity in a three-dimensional (3D) workspace, the method comprising the steps of:
electronically storing (i) a model of the machinery and its permitted movements and (ii) a safety protocol specifying speed restrictions of the machinery in proximity to a human and a minimum separation distance between the machinery and a human;
computationally generating, from the stored images, a 3D spatial representation of the workspace;
computationally mapping a first 3D region of the workspace corresponding to space occupied by the machinery within the workspace augmented by a 3D envelope around the machinery spanning all movements executed by the machinery during performance of the activity;
computationally identifying a second 3D region of the workspace corresponding to space occupied or potentially occupied by a human within the workspace augmented by a 3D envelope around the human corresponding to anticipated movements of the human within the workspace during the interval;
electronically storing a geometric representation of a restriction zone within the first 3D region of the workspace; and
during physical performance of the activity, restricting operation of the machinery in accordance with a safety protocol based on proximity between the first and second regions whereby the machinery remains within or outside the restriction zone.
16 . The method of claim 15 , further comprising the step of identifying a pose and trajectory of the machinery based at least in part on state data provided by the machinery.
17 . The method of claim 16 , wherein the state data is safety-rated and is provided over a safety-rated communication protocol.
18 . The method of claim 17 , wherein the state data is not safety-rated but is validated by information received from a plurality of sensors.
19 . The method of claim 15 , further comprising providing a control system having safety-rated and non-safety-rated components, restriction of the operation of the machinery to remain within or outside the restriction zone being performed by the safety-rated component.
20 . The method of claim 15 , wherein the restriction zone is a keep-out zone and further comprising the step of computationally determining a path along which the machinery can perform the activity without entering the keep-out zone.
21 . The method of claim 15 , wherein the restriction zone is a keep-in zone and further comprising the step of computationally determining a path along which the machinery can perform the activity without leaving the keep-in zone.
22 . The method of claim 15 , wherein the safety protocol specifies a protective separation distance as a minimum distance separating the machinery from the human.
23 . The method of claim 22 , further comprising, during physical performance of the activity, continuously comparing an instantaneous measured distance between the machinery and the human to the protective separation distance and adjusting an operating speed of the machinery based at least in part on the comparison.
24 . The method of claim 22 , further comprising, during physical performance of the activity, governing an operating speed of the machinery to a set point at a distance larger than the protective separation distance.
25 . The method of claim 24 , further comprising providing a control system having safety-rated and non-safety-rated components, the operating speed of the machinery being governed by the non-safety-rated component.
26 . The method of claim 15 , wherein the first 3D region is divided into a plurality of nested, spatially distinct 3D subzones.
27 . The method of claim 26 , wherein overlap between the second 3D region and each of the subzones results in a different degree of alteration of the operation of the machinery.
28 . The method of claim 15 , further comprising the steps of computationally recognizing a workpiece being handled by the machinery and treating the workpiece as a portion thereof in identifying the first 3D region.