ASSEMBLY FOR DETECTING COLLISION RISKS WHEN MOVING A LOAD AND CORRESPONDING MOVING METHOD

A method for detecting collision risks when moving a load includes the following steps:          attaching a plurality of proximity sensors around the lateral surface of the load;     lifting and moving the load using the lifting and moving equipment;     transmitting and displaying the signals generated by the proximity sensors on at least one display unit.

The present disclosure relates in general to the handling of loads using lifting and moving equipment.

BACKGROUND

When handling heavy loads using a lifting and moving equipment such as an overhead crane, there is a risk of collision between the load and its surroundings. In the event of collision, the load itself may be damaged. This is particularly problematic when the load is a high-value part, typically one manufactured for a customer.

During the collision, the equipment or structures placed around the load can also be damaged.

To minimize the risk of collision between the load and its environment, it is possible to place operators at different points around the load as it moves, to monitor the absence of contact.

Such an approach entails a significant risk for operators close to the load. Furthermore, in some cases, this approach requires exceptions to the safety rule prohibiting operators from entering the lifting cone.

SUMMARY

In this context, an aim of the present disclosure is to propose a method for moving a load allowing the risk of collision to be reduced while improving operator safety.

To this end, the present disclosure relates according to a first aspect of a method for moving a load having a closed-contour lateral surface, the method comprising the following steps:attaching a plurality of proximity sensors to the load, the proximity sensors being distributed around the lateral surface;attaching the load to a load lifting and moving equipment;lifting the load using the lifting and moving equipment, and moving the load using the lifting and moving equipment from an initial position to a final position with the load suspended from the lifting and moving equipment, each proximity sensor scanning whether an obstacle is in the vicinity of said proximity sensor during the movement of the load and generating a signal indicating whether an obstacle is in the vicinity of said proximity sensor during the movement of the load;transmitting the signals generated by the proximity sensors to the at least one display unit; anddisplaying said signals on the at least one display unit.

The proximity sensors distributed around the lateral surface of the load detect obstacles found in the vicinity of the load during its movement. The proximity sensors continuously send out a signal indicating whether an obstacle is nearby. The operators can visualize these signals using a display unit, such as a tablet.

The load and its environment can be monitored to ensure that there is no risk of collision between them, while remaining at a distance from the load.

As the proximity sensors are distributed around the lateral surface of the load, 360° monitoring is possible.

The operators are therefore no longer obliged to approach the load or enter the lifting cone.

Several display units can be used, enabling several people to simultaneously monitor the movement of the load and assess the risk of collision. For example, one of the display units may be entrusted to the operator controlling the lifting and moving equipment, another to the foreman, and one or more others to the operators involved in the load moving operation.

The method can also present one or more of the following characteristics, considered individually or according to any technically possible combination:the proximity sensors are miniature MEMS-type sensors;the proximity sensors are attached to a flexible support; the flexible support being arranged around the lateral surface of the load;the flexible support is a textile or a net;the said signals are displayed on the at least one display unit by displaying on an electronic screen of the at least one display unit a symbol representing the lateral surface of the load and, for each proximity sensor, a graphic element indicating whether an obstacle is in the vicinity of the said proximity sensor, the graphic element being produced using the signal generated by the said proximity sensor;the graphic element associated with each proximity sensor is positioned relative to the symbol representing the lateral surface of the load at a position representative of a position of said proximity sensor around the lateral surface;the flexible support comprises parts of different colors, the graphic elements associated with the proximity sensors located in a given color part being of said color;in the load lifting and moving step, when an obstacle is located close to one of the proximity sensors, said proximity sensor evaluates a distance between said proximity sensor and the obstacle, and the signal generated by said proximity sensor contains an indication characterizing said distance;the graphic element associated with said proximity sensor represents said indication characterizing the distance between the proximity sensor and the obstacle.

According to a second aspect, the disclosure relates to an assembly for detecting the risk of collision during the movement of a load having a lateral surface with closed contours, comprising:a flexible support;a plurality of proximity sensors attached to the flexible support, each proximity sensor being configured to scan whether an obstacle is in the vicinity of said proximity sensor and to generate a signal indicating whether an obstacle is in the vicinity of said proximity sensor;fixing the flexible support to the load, in a position such that the proximity sensors are distributed around the lateral surface;at least one display unit configured to display the signals generated by the proximity sensors;a transmitter, configured to transmit the signals generated by the proximity sensors to the at least one display unit.

The assembly1illustrated inFIGS.1to4is provided to detect the risk of collision during the movement of a load3having a closed-contour lateral surface5.

The load3is of any type: equipment or part of equipment being manufactured, finished equipment, equipment undergoing maintenance, or any other part to be transported by a lifting device.

The lateral surface5corresponds to the surface delimiting the load3in horizontal planes, that is, perpendicular to the vertical direction.

The load3is provided to be moved by lifting and moving equipment7.

In the example shown inFIG.1, the lifting and moving equipment7is an overhead crane. Alternatively, the lifting and moving equipment7can be a jib crane, a crane, or any other suitable equipment.

The lifting and moving equipment7includes a member8for attaching the load3to the lifting and moving equipment7.

This member8is, for example, a hook.

The lifting and moving equipment7is configured to enable the load3to be lifted, in other words, to lift the load3above the ground and hold it at a distance above the ground.

The lifting equipment7is also provided to move the load3from an initial position (shown in solid lines inFIG.1) to a final position (shown in dashed lines inFIG.1), while keeping the load3suspended from the lifting and moving equipment7.

Such devices are well known and will not be described here in detail.

The assembly1comprises a flexible support9and a plurality of proximity sensors11attached to the flexible support9.

The flexible support9is typically a textile. A textile is any material made up of interlocking fibers.

This textile is, for example, a woven fabric, in other words, a textile made up of threads arranged in a predetermined regular pattern. The threads are, for example, knitted or woven together.

The yarn is of any suitable type: yarn made of natural material, or plastic, or any other material.

Alternatively, the textile is non-woven or a net or a mesh.

Typically, the flexible support9, when placed flat, presents an elongated shape along a longitudinal direction L displayed inFIG.2.

In other words, the flexible support9presents the shape of a longitudinal strip.

The sensors11are distributed longitudinally along the flexible support9.

They are typically evenly spaced longitudinally along the flexible support9. For example, they are arranged in a single longitudinal line.

The sensors11are distributed along the entire longitudinal length of the flexible support9.

The longitudinal length of the flexible support9corresponds substantially to the perimeter of the lateral surface5, taken at the height at which the support9has to be arranged.

The assembly1also includes a system of fasteners13for attaching the flexible support9to the load3.

The system of fasteners13therefore allows the flexible support9to be attached to the load3, in a stable position.

In this position, the proximity sensors11are distributed around the lateral surface5, as shown inFIGS.1and3.

The longitudinal spacing between the proximity sensors11along the support9is chosen so that the detection zones covered by the sensors11overlap slightly.

In other words, the proximity sensors11are distributed over 360° around the vertical central axis of the load3. Arranged in this way, the detection fields of the proximity sensors11together cover the entire perimeter of the load.

Once in position, the proximity sensors11form a line with a closed contour, following the shape of the lateral surface5of the load3.

More precisely, they are arranged on a line having substantially the shape of the horizontal cross-section of the load3, taken at the height where the sensors11are arranged.

When the load3has a circular cross-section, as in the example shown inFIGS.3and4, the line of proximity sensors11forms a circle.

Typically, the flexible support9forms a strip with a closed contour, following the shape of the lateral surface5of the load3, in other words, having substantially the shape of the horizontal section of the load3, taken at the height where the flexible support9is arranged.

The system of fasteners13can be of any suitable type.

For example, when the lateral surface5of the load3is made of a magnetic material, the system of fasteners13comprises a plurality of magnetized elements rigidly attached to the support9and distributed longitudinally along the entire length of the support9.

If the support9presents a certain elasticity, the system of fasteners13can be provided to reversibly attach one longitudinal end of the support9to the opposite longitudinal end. In this way, the support9grips the load3elastically.

Any other system of fasteners is possible.

The proximity sensors11are advantageously miniature MEMS (Micro ElectroMechanical System) type sensors. Such sensors are of reduced size and weight, so that they can easily be integrated into a flexible tissue support or presenting in the form of a net.

The sensors are, for example, infrared sensors or TOF (time of flight) sensors.

These include sensors sold by ST Micro-Electronics in the VL53L range (for example VL53L3CX, VL53L1CX).

Each proximity sensor11is configured to scan if an obstacle is in the vicinity of said sensor11.

Each proximity sensor11has a detection zone covering a given angular sector, depending on the type of sensor and the desired accuracy.

The longitudinal spacing between the proximity sensors11along the support9, as indicated above, is chosen so that the detection zones of the sensors overlap slightly.

The maximum detection distance of each proximity sensor11is typically between 1 and 5 meters, for example 2 meters.

Each proximity sensor11is configured to generate a signal indicating whether an obstacle is in the vicinity of said proximity sensor, and to indicate the distance between the sensor and the obstacle.

“In the vicinity of said proximity sensor” is understood to mean that the obstacle is within the detection zone of the sensor.

The assembly1also comprises at least one display unit15, configured to display the signals generated by the proximity sensors11.

The display unit15is typically a portable electronic device, such as a smartphone, tablet, laptop, etc.

Alternatively, the display unit15is a fixed computer.

Furthermore, the assembly1includes a transmission device17, configured to transmit the signals generated by proximity sensors11to the at least one display unit15.

The transmission device17typically comprises a transmitter19carried by the flexible support9.

The transmission device17also includes, for the or each display unit15, a receiver21configured to communicate with the transmitter19.

The transmitter19communicates with the or each receiver21over the air. The transmission uses a Wi-Fi, Bluetooth or Lorawan protocol.

Advantageously, each proximity sensor11is connected to the transmitter19in a wired manner.

The wires transmitting the signal emitted by each proximity sensor11to the transmitter19are carried by the flexible support9.

The or each display unit15includes an electronic screen23.

The or each display unit15is configured to display the signals generated by the proximity sensors11by displaying on the electronic screen23a symbol25representing the lateral surface5of the load3and, for each proximity sensor11, a graphic element27indicating whether an obstacle is in the vicinity of said proximity sensor11(FIG.4).

The graphic element27is created using the signal generated by said proximity sensor11.

Advantageously, the proximity sensor11is configured so that, when an obstacle is in the vicinity of said sensor, a distance between said proximity sensor11and the obstacle is evaluated.

In this case, the signal generated by the proximity sensor11contains an indication characterizing said distance.

The graphic element27associated with said proximity sensor then represents said indication characterizing the distance between the proximity sensor11and the obstacle.

Typically, the symbol25representing the lateral surface5of the load3is a geometric shape corresponding substantially to the cross-section of the load3taken in a horizontal plane substantially at the level where the flexible support9is arranged.

The symbol25typically corresponds exactly to the horizontal cross-section of the load, particularly when this shape is simple.

In the example shown inFIGS.3and4, load3has a circular horizontal cross-section at the level of the flexible support9, and symbol25is a circle.

In the example shown inFIGS.5and6, the load3has a rectangular horizontal cross-section at the level of the flexible support9. The symbol25shown on the display unit15is also a rectangle.

The graphic element27comprises, for example, one or more bars.

For example, graphic element27:has no bars if no obstacle is detected by the proximity sensor11;comprises one or more bars when an obstacle is detected by the proximity sensor11, the number of bars being inversely proportional to the distance between proximity sensor11and the obstacle.

As illustrated inFIGS.4and6, the bars are parallel to each other and are stacked starting from the symbol representing the lateral surface of the load.

For example, the sensor range, in other words, the maximum distance at which the sensor can detect an obstacle, is divided into several ranges, and a different number of bars is associated with each range. The range furthest from the sensor is associated with a single bar. The range corresponding to the immediate proximity to the sensor is associated with the maximum number of bars, for example five bars in the example shown.

The intermediate ranges are associated with two bars, three bars or four bars.

The graphic element27may not be constituted of bars of the type shown inFIGS.4and6but may be of any other suitable type.

The signal generated by each proximity sensor11contains, for example, a value of the distance measured by the proximity sensor11between the sensor11and the obstacle. In this case, the or each display unit15is configured to determine the number of bars corresponding to each measured distance value. This determination is carried out using a correspondence table or equation.

Alternatively, the signal includes a code capable of adopting several discrete values, each value corresponding to a range of distance between the sensor and the obstacle. In this latter case, the or each display unit15is configured to directly associate a number of bars with each code value.

Advantageously, the graphic element27associated with each proximity sensor11is positioned relative to the symbol25representing the lateral surface5of the load3at a position representative of the position of said proximity sensor11around the lateral surface5.

For example, one of the proximity sensors11is considered as an angular position reference. The graphic element27associated with this reference proximity sensor is considered as an angular position reference on the electronic screen of display unit15.

The graphic element27associated with another proximity sensor11is positioned at a specific angular position around the symbol25relative to the reference graphic element. This determined angular position corresponds substantially to the angular position of the other proximity sensor11around the side surface5relative to the reference proximity sensor11.

As illustrated in the figures, the flexible support9advantageously includes the parts29of different colors.

For example, the flexible support9is divided into several longitudinally juxtaposed parts29, each of a different color.

The graphic elements27associated with the proximity sensors11located in a part29of a given color are of said color on the display unit15.

This thus makes it easy, by looking at the electronic display23on the display unit15, to tell which part of the load3is closest to an obstacle.

In the example shown, each part29includes two proximity sensors11.

For example, each graphic element27is created using only the signal generated by one of the proximity sensors11. In this case, it characterizes only the signal generated by said sensor.

Alternatively, each graphic element27can be created using the signals generated by several proximity sensors11juxtaposed longitudinally along the support9. For example, each graphic element27is created using the signals generated by two proximity sensors11.

In the example shown, each graphic element27is created using the signals generated by the proximity sensors11located in the same part29of the flexible support9.

In this case, for example, graphic element27is created in the following manner:if neither of the two proximity sensors11detects an obstacle, the graphic symbol27corresponds to a signal indicating that there is no obstacle in the vicinity;if at least one of the two proximity sensors11detects an obstacle, the graphic element27corresponds to a signal indicating that an obstacle is nearby.

If the signal generated by each proximity sensor contains an indication characterizing the distance between the sensor and the obstacle, the graphic element is created by taking into account the smallest of the distances evaluated by the two proximity sensors.

If one or both proximity sensors do not detect an obstacle, this distance is not taken into account.

The present disclosure also relates to a method for moving a load, which will now be described.

The load3is as described above, and presents a closed-contour lateral surface5.

The method comprises a step of attaching a plurality of proximity sensors11to the load3, the proximity sensors11being distributed around the lateral surface5.

The proximity sensors11are of the type described above.

As mentioned above, they are advantageously attached to a flexible support9, the flexible support9being arranged around the lateral surface5of the load3.

The flexible support9is of the type described above.

As described above, the proximity sensors11are arranged to form at least one closed-contour line around the side surface, located at a given height from the load3.

The method further includes a step of attaching the load3to a load lifting and moving equipment7.

As mentioned above, this equipment7is, for example, an overhead crane, a jib crane, a crane or any other suitable equipment.

The method further includes a step of lifting the load3using the lifting and moving equipment7(represented by the vertical arrow pointing upwards on the left ofFIG.1) and moving the load3using the lifting and moving equipment7.

This movement is shown by the horizontal arrow inFIG.1.

The load is moved from an initial position (solid lines on the left ofFIG.1) to a final position (broken lines on the right ofFIG.1) with the load3suspended from the lifting and moving equipment7.

During movement of the load3, each proximity sensor11scans for any obstacle31found in the vicinity of said proximity sensor11. This scanning is carried out continuously, or at extremely short intervals with respect to the time required to lift and move the load3.

The proximity sensor11generates a signal indicating whether an obstacle31is in the vicinity of the sensor11while the load3is being moved. Again, this signal is generated continuously, or with an extremely low periodicity relative to the time required to lift and move the load3.

The method also includes a step for transmitting the signals generated by the proximity sensors11to the at least one display unit15.

The signal is transmitted as described above.

Each proximity sensor11typically transmits the signal by wire to the transmitter19, which transmits it over the air to the receiver21on the or each display unit15.

The or each display unit15is of the type described above. For example, it is a tablet.

The method also includes a step of displaying said signals on the at least one display unit15.

This display is carried out as described above.

The displacement method and the detection assembly of the present disclosure can have multiple variants.

According to one alternative illustrated inFIG.7, the flexible support9is not a textile but is a net or a mesh structure. In this case, the proximity sensors11are attached to the nodes of the net or mesh.

According to one alternative not shown, the proximity sensors11are not attached to a flexible support, but are attached directly to the lateral surface5of the load3. For example, they are attached individually, by magnetic means.

According to another alternative, the proximity sensors11are not all attached to a single flexible support. They are distributed over several flexible supports; each flexible support being attached to the load.

According to one alternative illustrated inFIG.7, the proximity sensors11are arranged on the flexible support9in several longitudinal lines, parallel to one another.

In this case, the flexible support9is very high, and all the proximity sensors11are attached to the same flexible support9.

The proximity sensors11form several closed-contour lines around the lateral surface5, at different heights of the load3.

Each closed-contour line follows the shape of the lateral surface5of the load3at the height at which the line is arranged.

This arrangement is particularly advantageous if the load is very high, or if its cross-section varies according to the height.

In this case, the proximity sensors should be arranged around the most protruding parts of the load.

According to another alternative, the proximity sensors are arranged according to a closed contour line, but at different heights of the load. For example, one part of the proximity sensors is arranged relatively lower, and another part of the proximity sensors relatively higher. This is suitable in cases where the horizontal cross-section of the load is irregular, with parts protruding in different directions and located at different heights.

According to one alternative embodiment, the signal generated by each proximity sensor indicates only whether an obstacle is in the vicinity of said proximity sensor11and does not contain any indication characterizing the distance between the obstacle and the proximity sensor.

The graphic element27is, therefore, of a different type to the graphic elements shown inFIGS.4and6. For example, the graphic element contains a symbol such as a bar when an obstacle is in the vicinity of proximity sensor11, and shows nothing at all, in other words, zero bars, when no obstacle is detected in the vicinity of the proximity sensor.

The signal generated by the proximity sensor in this case is typically a binary signal capable of adopting two values: one value if an obstacle is detected, and another value if no obstacle is detected in the vicinity of the sensor.

The method of moving and the detection assembly of the present disclosure presents multiple advantages.

Because the proximity sensors are miniature MEMS-type sensors, they present a reduced weight and volume, and can be easily attached to a flexible support.

The fact that the proximity sensors are attached to a flexible support, they can be easily arranged around the lateral surface of the load. The flexible support conforms to the shape of the lateral surface, allowing the sensors to be positioned as close as possible to the lateral surface.

When the flexible support is a textile or a net, the sensors can easily be attached to the support. In addition, the support can be easily attached to the load. It does not add weight or bulk.

The fact that viewing the signals generated by each sensor on at least one display unit, is implemented by displaying on the electronic screen a symbol representing the lateral surface of the load and, for each proximity sensor, a graphic element indicating whether an obstacle is in the vicinity of said proximity sensor, the graphic element being created using the signal generated by said proximity sensor, the operators have a quick and easy view of collision risks.

When the graphic element associated with each proximity sensor is positioned relative to the symbol representing the lateral surface of the load at a position representative of a position of said proximity sensor around the lateral surface, the operators can easily apprehend which zone(s) of the lateral surface is/are close to an obstacle.

The fact that the flexible support comprises parts of different colors, with the graphic elements associated with the proximity sensors located in a given colored part being of said color, allows the operators to apprehend even more easily, which zone of the lateral surface is close to an obstacle.

The fact that each proximity sensor evaluates a distance between said proximity sensor and the obstacle, and that the signal generated by said proximity sensor contains an indication characterizing said distance, further reinforces safety during load movement. The operators are provided with information indicating whether an obstacle is approaching or moving away and allowing them to identify which zone of the lateral surface is closest to an obstacle.