Enhanced proximity alarm system and method

Abstract

An enhanced proximity alert system and method. A method for detecting whether a tag is proximate to a spreader, the method comprising the steps of: detecting the tag by a sensing device mounted to the spreader; positioning to the tag in a hazard zone relative to the sling, and then; activating a danger zone warning to an operator of the sling; if the tag is no longer positioned in the danger area; determining whether the label enters a warning area or not; if the label is positioned in the warning area, the danger area warning is cleared; if the tag is not positioned in the warning area or the danger area, determining that the tag is positioned in the warning area or the danger area; and keeping the danger area warning.

Description

Technical Field

[0001] The present invention relates to safety protocols and systems to ensure that such protocols are applicable to personnel in the vicinity of a spreader and a container during loading and unloading. Background Art

[0002] As heavy equipment for handling heavy loads, human safety is always a concern for spreaders not only during operation but also when the spreader is under maintenance.

[0003] During operation, a crane operator can operate the crane from a crane cab at a high position in the crane or from a remotely located control room via a camera. Considering the high level of activity and the wide operating area, it is impossible for the crane operator to always notice the presence of every person in the spreader operation area. This will ultimately lead to accidents, such as the spreader or container hitting or pressing on a person, resulting in serious injuries / deaths.

[0004] During maintenance, for example, when the spreader is in a maintenance workshop, there are usually multiple maintenance workers working on and around the spreader. When these workers are still on or around the spreader, the activation of any mechanism on the spreader may cause serious injuries or deaths.

[0005] Proximity Alert System (PAS) is generally a term for systems that warn industrial vehicles that they are very close to pedestrian workers. If these vehicles are close to where pedestrians are working, it can be installed on forklifts, reach stackers, gantry cranes, etc. – which require a warning system.

[0006] PAS is designed to reduce the risk of collisions through asset and personnel detection and warning, thereby enhancing workplace safety. The system can incorporate one or more detection technologies (RFID, UWB, GPS, electromagnetic sensors, and (optionally) real-time video surveillance) for redundancy and safety to detect user-defined heavy vehicles, light vehicles, personnel, and obstacles.

[0007] PAS is generally a bilateral warning system where both pedestrians and drivers can be aware of the dangerous situation and be alerted to the dangerous situation via, for example, auditory and visual alarms.

[0008] Active tags are worn by personnel, installed on assets, or set on sidewalks, intersections, and around hazards. When entering the detection area, they are recognized by the detection system, which can be installed in a fixed position or on a vehicle.

[0009] This triggers an auditory or / and visual alarm warning the vehicle operator that the tag is very close to the vehicle.

[0010] When the standard PAS technology is applied to a spreader, there are some limitations that need to be overcome. Contrary to ground transportation vehicles, spreader operation involves lifting the spreader, which hoists the spreader through 3D space. This creates new problems not present in truck-mounted PAS systems. When the spreader lifts a container, the container blocks the area directly below the spreader where the PAS is mounted. There is currently no detection technology that can directly detect people under the container, even relatively promising technologies such as UWB. Summary of the Invention

[0011] In a first aspect, the present invention provides a method for detecting whether a tag is approaching a spreader, the method comprising the steps of: detecting the tag by a sensing device mounted to the spreader; locating the tag in a danger zone relative to the spreader, and then; activating a danger zone warning for an operator of the spreader; if the tag is no longer located in the danger zone; determining whether the tag has entered a warning zone; if the tag is located in the warning zone, clearing the danger zone warning; if the tag is not located in the warning zone or the danger zone; maintaining the danger zone warning.

[0012] In a second aspect, the present invention provides a system for detecting whether a tag is approaching a spreader, the system comprising: one or more sensing devices arranged to detect the tag by a sensing device mounted to the spreader; the one or more sensing devices communicating with a control system; the sensing devices arranged to locate the tag in a danger zone relative to the spreader; the control system arranged to activate a danger zone warning when receiving a signal from the one or more sensing devices; the control system further arranged to clear the danger zone warning if the sensing device detects that the tag has entered the warning zone; if the sensing device no longer detects the tag in the danger zone or the warning zone, the control system is arranged to maintain the danger zone warning. Brief Description of the Drawings

[0013] It will be convenient to further describe the present invention with reference to the drawings which illustrate possible arrangements of the present invention. Other arrangements of the present invention are possible, and thus the particularity of the drawings should not be understood as superseding the generality of the foregoing description of the present invention.

[0014] Figure 1 is a flowchart according to an embodiment of the present invention; Figure 2 is a flowchart according to another embodiment of the present invention; Figure 3 is a schematic front view according to another embodiment of the present invention; Figure 4 is a perspective view according to another embodiment of the present invention. Detailed Description of the Invention

[0015] For PAS, RFID and UWB technologies are some of the more common choices because they possess many of the desired characteristics of a PAS system, such as those listed below:

[0016] Due to the ability to program two different 360° detection zones (warning / hazard), the system according to the present invention can be configured to trigger audible and visual alarms to warn of the presence of an operator, further allowing staged warnings and vehicle deceleration (subject to vehicle compatibility verification).

[0017] In one embodiment, the system may include sensing devices mounted in appropriate positions on the spreader, such as UWB (Ultra-Wideband) sensing devices. Workers in the spreader operation area or maintenance area will wear personal tags that can be detected by the PAS sensing devices.

[0018] The sensing devices may define at least two zones around the spreader, a warning zone and a hazard zone.

[0019] In essence, when the system detects a person / tag in the warning zone, the system can warn the operator but allow the spreader to move / operation to continue. Conversely, the detection of a person / tag in the hazard zone can prevent the activation of any spreader movement and stop the movement even if it has already started.

[0020] Outside the warning zone, which may be within or outside the PAS detection range, it can be assumed or defined as a third zone, which is a safety zone where no warning will be issued and operation can continue.

[0021] Figure 1 And referring Figure 3 to, a flowchart of the system is provided. Regarding Figure 3 a PAS 140 according to an embodiment of the present invention defines four separate zones, where the outer zone 160 is outside the detection range. The second and third zones 145, 150 are the warning zone and the hazard zone respectively, and the fourth zone 165 is directly below the spreader 155. A person 170 with a tag can provide an interrogation response 180 to an interrogation signal 175 transmitted from the spreader 155. The meaning of this response and where it is sent from form the basis of the system according to the present invention.

[0022] Returning to Figure 1 which shows an embodiment where, upon starting the 10 system, all tags within range are detected 15. The tags are located at different positions within the warning zone 20 or the hazard zone 25. If no tags are detected, the system continues to interrogate for tags entering the detection range of either zone.

[0023] For tags located within warning zone 30, the warning for the warning zone is activated, but no further action is taken. Thus, the spreader will continue to operate. For tags located within danger zone 35, the system will continuously query 45 to confirm whether the tagged person is still within the danger zone. If so, the danger zone warning will be triggered 50. If instead, the tag is located within warning zone 55, the warning will be cleared 60. However, if the tag is no longer detected within the danger zone and the tag is not within warning zone 55, the risk of the tagged person approaching the spreader causes the danger zone warning to be activated 50.

[0024] In principle, the system according to the present invention will keep track of the number of people (number of tags) within the warning zone and the danger zone. Any detection of a person who has left the danger zone must detect the same person entering the warning zone, otherwise it will be assumed that he is already beneath the container (or any blind spot within the danger zone), and thus it will be assumed that he is still within the danger zone.

[0025] It will be appreciated that by identifying the tag approaching the spreader, in some embodiments, this may include the tag being beneath the spreader. In another embodiment, approaching the spreader may be limited to those cases where the tag and thus the person are beneath the spreader. It should be understood that the demarcation between the danger zone and beneath the spreader may vary with: i) environmental conditions; ii) container type; iii) signal strength, etc.

[0026] Thus, there may be a grey zone between the danger zone and "beneath the container". For this reason, approaching may include only "beneath the container" or also within such a grey zone.

[0027] Figure 2 Another embodiment is shown which adds a "beneath the container mode" to the Figure 1 system. After querying the system 55 to determine whether a tag from the danger zone has appeared within the warning zone, if no tag is detected within the warning zone, the "beneath the container mode" is activated 65. Further querying determines whether the tag has reappeared within the danger zone 70 or the warning zone 75. If so, the corresponding response is to return the system to normal operation of querying the relevant zones 30, 35. If not, a separate beneath the container warning 80 is triggered and the operation of the spreader is stopped.

[0028] It will be appreciated that the (one or more) sensing devices communicate with the control system in order to locate and determine the position of the tag, and subsequent actions of activating the danger zone or beneath the container warning, and stopping the operation of the spreader. In another embodiment, the stopping operation of the spreader may be controlled by the operator, who may freely act on noticing the warning.

[0029] Figure 4A schematic diagram of the maintenance workshop 185 is shown. The spreader 200 is usually placed on a maintenance stand and is powered and controlled by a spreader test panel. The test panel is used to control the movement of the mechanisms within the spreader, as required for inspection, maintenance, and testing.

[0030] The system according to the present invention is started to ensure that safety protocols are met within the workshop. Corresponding warning zones 190 and danger zones 195 may be established based on the distance from the spreader 200.

[0031] In this case, since the spreader has been placed on the stand, it is not possible to have the situation of "under the container". However, Figure 1 the process steps of can still be used to ensure that corresponding warnings are triggered if tags enter the respective zones.

[0032] Once the spreader is connected to the dedicated test panel, the PAS system will automatically switch the detection mode from operation to maintenance.

[0033] For the maintenance system 185, the danger zone 195 is defined as a central zone that encloses the area within the spreader plus the area immediately adjacent around the spreader (e.g., 1 meter). As for the warning zone 190, it can be a ring close to the danger zone. For example, it can start 1 meter behind the spreader and end 2 meters behind the spreader. Outside the warning zone 190, any detections will only be for reference and the system will not take action.

Claims

1. A method for detecting whether a tag is close to a spreader, the method comprising the following steps: Detecting the tag by a sensing device installed on the spreader; Locating the tag in a danger zone relative to the spreader, and then; Activating a danger zone warning for an operator of the spreader; If the tag is no longer located in the danger zone; Determining whether the tag has entered a warning zone; If the tag is located in the warning zone, clearing the danger zone warning; If the tag is not located in the warning zone or the danger zone, then; Maintaining the danger zone warning.

2. The method according to claim 1, after the maintaining step, the method further comprises the following steps: If the tag is subsequently located in the warning zone, clearing the danger zone warning.

3. The method according to claim 1 or 2, after the maintaining step, the method further comprises the following steps: Starting a mode under the container; Determining whether the tag is within the danger zone; If not within the danger zone, determining whether the tag is within the warning zone; If not within the danger zone or the warning zone, then; Activating a warning under the container.

4. The method according to any one of claims 1 to 3, wherein the activation of the danger zone warning includes stopping the operation of the spreader.

5. The method according to claim 4, wherein the activation of the warning under the container includes stopping the operation of the spreader.

6. A system for detecting whether a tag is close to a spreader, the system comprising: One or more sensing devices arranged to detect the tag by a sensing device installed on the spreader; The one or more sensing devices communicate with a control system; The sensing devices are arranged to locate the tag in a danger zone relative to the spreader; The control system is arranged to activate a danger zone warning when receiving a signal from the one or more sensing devices; The control system is further arranged to clear the danger zone warning if the sensing device detects that the tag has entered a warning zone; If the sensing device no longer detects the tag in the danger zone or the warning zone, the control system is arranged to maintain the danger zone warning.

7. The system according to claim 6, wherein the control system is arranged to start a mode under the container if the tag cannot subsequently be detected in the danger zone or the warning zone; The control system then is arranged to activate a warning under the container.

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