Smart bin picking system

Abstract

The invention relates to a smart bin picking system (1) comprising a bin (10) fitted with at least one adjustable bottom portion (10A), a displacing apparatus (11) arranged to move said adjustable bottom portion (10A) between a first position (P1) where the bin (10) has a maximal depth (DMax), and a second position (P2) where the bin (10) has a minimal depth (DMin), wherein said smart bin picking system (1) further comprises a set of sensors (12) including a subset of at least one visual sensor (120) arranged within an annular space (S) surrounding any vertical projection of the perimeter (P) of the adjustable portion (10A) on any horizontal plane, and wherein the sensors (12) and the displacing apparatus (11) are coupled through a control unit (14) that drives the displacing apparatus (11) based on data acquired by the sensors (12).

Description

[0001] SMART BIN PICKING SYSTEM

[0002] Technical Field of the Invention

[0003] The present invention relates to the field of bin picking. More specifically, the invention relates to a smart bin suitable for advanced bin picking.

[0004] State of the Art

[0005] In order to sort parts randomly fed, bowl feeders, conveyors, vibrating feeders, and hoppers are well-known technologies, in which the coordinated shaking movement of a sieve can flip and move the parts to specific areas so that they can be delivered in a specific unloading spot. These kinds of apparatuses are prone to generating shocks between parts though, which can damage them, and are also not quite suitable for heavy or large parts requiring costly actuators, in addition they are usually not versatile as some mechanical elements need to be adjusted when changing the part to be fed.

[0006] Randomized Bin Picking systems are also known. These systems are designed to locate loose parts, with 6 degrees of freedom, in a container referred to as a bin and then extract them from the bin. A Bin Picking system can be broken down into three functional subsystems: a visual sensor system aimed at locating the parts inside the container, a robot control system that generates a trajectory and drives the robot during a picking operation, and a gripper attached to the robot that can pick parts from the multiple orientations in which they may lie inside the bin.

[0007] Although solutions are already available to address the above- mentioned problems, they are currently not very efficient, because they are too slow, inaccurate, and often unable to empty the container completely. In addition, the design of the gripper is usually a painful task (try-and-error based) limiting the freedom of the robot and creating the need for advanced robot trajectories for collision avoidance purposes. Thus there exists a need for solutions free of these known limitations.

[0008] Patent US11591194B2 describes a container with an adjustable bottom fitted with a set of fullness detection sensors.

[0009] Summary of Invention

[0010] An object of the present invention is to propose a new device that helps enhance bin picking performances.

[0011] This object is attained by means of the features of main claim 1 . In particular, this object is attained thanks to a smart bin picking system comprising a bin fitted with at least one adjustable bottom portion, and displacing apparatus arranged to move this adjustable bottom portion between a first position where the bin has a maximal depth, and a second position where the bin has a minimal depth, wherein the smart bin picking system further comprises a set of sensors including a subset of at least one visual sensor arranged within an annular space surrounding any vertical projection of the perimeter of the adjustable portion on any horizontal plane, and wherein the sensors and the displacing apparatus are coupled through a control unit driving the displacing apparatus based on data acquired by the sensors.

[0012] An advantage of the provided solution is to offer an intelligent bin with smart integrated visual sensors, which are arranged in such a way that they are no more obstructing the access to the top of the bin. This way, localization detection of parts can be improved while still granting an easy access to the bin, and emptying the bin is made easier. Overall, speed and precision of picking operations are thus improved.

[0013] According to a preferred embodiment for the smart bin picking system according to the present invention, the annular space where the visual sensors are arranged is placed above the top edge of every lateral wall of the bin. This way, it is ensured that all the cameras are always placed above the parts to be monitored at any stage irrespective of the positioning of the adjustable bottom portion, so that efficiency can be improved throughout the whole bin picking process.

[0014] According to a preferred embodiment for implementing the smart bin picking system according to the present invention, the subset of visual sensors consists of several cameras arranged in a halo fitted on top of a box receiving said bin.

[0015] This way, a fully integrated design is provided for the bin, allowing for easy incorporation of cameras, i.e. preferably at least a couple of such visual sensors, on top of a box, in a modular fashion and without obstructing access to the bin and while simultaneously requiring minimal additional space for lodging them above the box.

[0016] According to yet another more preferred embodiment for the smart bin picking system within the framework of the present invention, the halo further includes an illuminating system.

[0017] An advantage of this solution is to use the same annular space crowning the top of the box to include both sensors and an illuminating system, so that the camera detection are further improved without requiring too much additional space for this performance enhancement.

[0018] According to still another more preferred embodiment for the smart bin picking system of the present invention, the illuminating system comprises LEDs arranged at regular intervals.

[0019] An advantage of this interleaved scheme for arranging lighting elements and cameras is to optimize space requirement while generating no additional hindrance either in terms of height or in terms of radial obstruction for accessing the top of the bin, while further improving the camera detection performances by emulating an almost continuous annular light source oriented towards the inside of the bin. According to another preferred embodiment for the smart bin picking system of the present invention, the box further comprises a lateral opening and a drawer arranged for supporting the bin inside the box and moving it outside of it.

[0020] Such a design, comprising preferably a drawer having a hollow bottom in order to let e.g. a vertical piston pass through to move the adjustable bottom upwards and downwards, allows for an easier unloading process without requiring the part to be brought above the upper lips of the box. As a result, the unloading process can be simplified, even without any requiring any automation process at this stage.

[0021] According to another preferred embodiment for the smart bin picking system of the present invention, the displacing apparatus is made of at least three vertical pistons arranged at the periphery of leveling plate used as adjustable bottom portion, these at least three vertical pistons being further arranged for vibrating and tilting the adjustable bottom portion.

[0022] An advantage of this solution is to provide a simple design for reshuffling parts in order to facilitate the subsequent picking process for the robot; the vibration combined with the tilting offers a most efficient solution to rearrange the 6D positioning of the parts, i.e. not only their physical location, but also their orientation at each location. According to a most preferred embodiment, four vertical pistons are foreseen, each of them being provided at a corner of a rectangular plate used as adjustable bottom portion.

[0023] According to an alternative embodiment for the smart bin picking system of the present invention, the subset of visual sensors consists of several cameras mounted on a fixed framework enclosing the bin.

[0024] Such an alternative layout for the cameras is very straightforward and most suitable for an integration into a conveyor system, whereby the geometrical shape of the framework and the arrangement of the cameras can be easily adjusted to the needs (number per rows, etc.). Installation and replacement of cameras is also very easy. According to a preferred embodiment for the implementation of such an alternative embodiment for the present invention, the displacing apparatus is a central vertical piston arranged below a conveyor system.

[0025] Such an arrangement for the displacing apparatus is very cost effective and easy to implement within a conveyor system, with preferably belts on lateral sides letting the central piston pass through when fine tuning of the height of the adjustable bottom portion is necessary.

[0026] According to another preferred embodiment for the smart bin picking system of the present invention, the adjustable bottom portion is a chamfered leveling plate.

[0027] An advantage of such a solution is that the chamfers can prevent any pinching of parts in the comers, which would then cause some of them to get stuck. As a result, the parts can be moved more freely around the leveling plate whenever necessary, on the one hand, and on the other hand there is less risk of preventing the vertical movement of the adjustable bottom portion to occur due to the blocking of a part, which may cause serious damages to the bin.

[0028] According to another preferred embodiment for the smart bin picking system of the present invention, the adjustable bottom portion has pyramidal pins.

[0029] Such a layout for the adjustable bottom portion, which can be realized either in a monobloc or in modular fashion (in that case as a removable mat disposed on top of the adjustable bottom portion), can help avoid rolling of parts so that they keep the same position and orientation, especially in the end when the number of parts is reduced inside the bin, hence simplifying the picking process and reducing the overall picking cycle times.

[0030] According to another preferred embodiment for the realization of the present invention, the smart bin picking system further comprises an articulated picking robot fitted with a gripper, and the control unit is arranged to drive said displacement apparatus based further on operational characteristics of the picking robot.

[0031] Such a configuration provides an excellent flexibility with the ability to apply reverse kinematics based on a set of predefined parameters such as the position of the base portion of the robot, the current position of the gripper, the length of each arms etc. so that the movement of one pickable part to another can be optimized and customized based on the available robots.

[0032] According to an even more preferred embodiment for the smart bin picking system of the present invention, the picking robot is mounted on a base and has a first arm articulated via a first joint to the base, a second arm articulated via a second joint to the first arm, wherein the gripper is articulated over a third joint with respect to the second arm, and wherein the ratio between a first length of the first arm and a second length of the second arm is at least 2:1.

[0033] Such a configuration with a gripper arranged at the end of a shorter arm allows to reduce the complexity of the robot trajectories, and thus achieve further gains in efficiency with respect to regular robots known from the prior art; this is further enabled by the levelling of the adjustable bottom part because the picking of parts needs, in that case, to be done in a relatively shallow space.

[0034] According to yet another preferred embodiment for the smart bin picking system of the present invention, the control unit is arranged for, after a first step of feeding parts into the bin, driving the displacing apparatus in a second step based on data acquired by said sensors so that at least one part within the bin lies in a predefined working zone for the picking robot, and for performing, in a third step, a selection operation of a pickable part based on data acquired by the subset of visual sensors.

[0035] An advantage of such a solution is to allow for optimized picking itineraries after having put the parts in a graspable zone with the levelling of the adjustable bottom part. In other words, a sequence of operation is followed where it is first made sure that pickable parts are available, and then which path should be followed by the robot to pick such available pickable parts in a most efficient way.

[0036] According to yet another even more preferred embodiment for the smart bin picking system of the present invention, the gripper is further provided with an additional visual sensor, and wherein data acquired by this additional visual sensor are used in the second step and / or the third step.

[0037] As a result, this additional camera can be used either for improving the image resolution and support the decision making process as to whether the adjustable bottom part should be lifted or not, and, additionally or alternatively, the data of this additional camera can also be used to define an optimized picking itinerary for the robot based on localization information, including possibly more precise neighboring information between parts as compared to the localization information yielded from other visual sensors.

[0038] Brief Description of Drawings

[0039] Fig.1 shows a typical sequence of operations using a smart bin having an adjustable bottom portion in the framework of the present invention;

[0040] Fig.2A & Fig 2B are showing perspective views of a fully integrated bin in two antagonist positions according to a first preferred embodiment for the invention;

[0041] Fig.3 is showing a perspective view of a fully integrated camera halo to be mounted on the bins shown in Figs 2A & 2B;

[0042] Fig.4 shows a perspective view of a fully integrated bin fitted with a drawer for manual loading operations;

[0043] Fig. 5 shows a top view of a bin according to the preferred embodiment illustrated on Figs 2A & 2B, with an adjustable portion formed by a rectangular chamfered leveling plate, highlighting the relative positioning of the cameras with respect to the perimeter of the leveling plate, i.e. the inside of the lateral walls of the bin.

[0044] Figs. 6A & 6B show perspective views of a bins according to a preferred embodiment for the present invention, with adjustable bottom portions formed by rectangular leveling plates, in two different positions, corresponding to a minimal and a maximal depth;

[0045] Figs.7A & 7B show perspective views of the bins with adjustable bottoms according to a preferred embodiment, highlighting a four piston activation mechanism for the displacing apparatus;

[0046] Fig. 8A & 8B show perspective views of the bins with adjustable bottoms according to another preferred embodiment, involving a central piston activation mechanism for the displacing apparatus.

[0047] Fig. 9 shows a preferred embodiment for the realization of the top surface of the adjustable bottom portion according to the invention, with pyramidal pins.

[0048] Fig. 10 shows a perspective view of a conveyor system fitted with bins with adjustable bottom portions according to a second embodiment, and also including a central piston actuator and a fixed parallelepipedal frame.

[0049] Fig. 11 shows a perspective view of a smart bin system according to a preferred embodiment for the present invention, including a picking robot with an articulated arm and whose gripper is fitted with an additional camera.

[0050] Detailed Description of the Invention

[0051] In the following, preferred embodiments for implementing the present invention will be described with the help of Figs 1 -11. This non-exhaustive list of embodiments is given by way of example only, and is not intended to be construed as limiting for the scope of protection for the present invention. Fig.1 introduces the smart bin concept of the present invention by indicating a typical sequence of operations using a smart bin 10 having an adjustable bottom portion 10A surrounded by lateral side walls 10B according to a preferred embodiment for the present invention. Over the top edges T of every side wall 10B, a set of sensors 12 is arranged in a way that they are neither obstructing the picking operations performed by an external robot (not illustrated in this figure for the sake of clarity but, a preferred version of which being illustrated later in Fig. 11 ), nor the filling and emptying operations. This is achieved by placing the sensors 12 outside of an inner space (I) extending the inner volume of the bin, by protruding vertically above it. This inner space (I) corresponds to the volume included inside the two dashed line extending the inner part of the lateral side walls 10B. This set of sensors 12 preferably comprises at least one visual sensor 120, i.e. a camera, and more preferably comprises at least a couple of cameras, i.e. at least two in order to yield the best possible peripheral view of the inside of the bin. However, this set of sensors is not necessarily made of cameras only, and may comprise other types of sensors, such as laser scanners to determine the presence of parts inside the bin, or weight and / or tactile sensors the detect the presence and amount of parts lying on the adjustable bottom portion 10A. In other words, the set of sensors 12 is designed to comprise a subset of visual sensors 120, made of at least two cameras that are foreseen to improve simultaneously the detection and localization resolution of parts 2 inside the bin 10.

[0052] In a first step (01 ), parts 2 a fed into the bin 10; this can be done in an automatized way, whereby the adjustable bottom portion 10A can be gradually moved down along the feeding in order to avoid shocks of the parts against the adjustable bottom portion 10A from too far high, or manually, like in the example illustrated by Fig. 4. The driving of displacing apparatus 11 is triggered in a second step (02), irrespective of the fact that the adjustable bottom portion 10A has been moved while feeding the bin 10 or not. The movement of the displacing apparatus 11 is based on data acquired by the sensors 12, and performed in a way that at least one part 2 within the bin 10 lies in a predefined working zone Z for a picking robot, just like the picking robot 17 illustrated later in Fig. 11 . This means that in the zone located above the dashed line of Fig. 1 , the robot is able to grasp parts lying inside the bin 10. As a result, after this operation, at least one pickable part 2A is yielded, and in turn, in a third step (03), a selection operation of one of these identified pickable parts 2A is performed based on data acquired by the subset of visual sensors 120. In other words, it is possible to perform an efficient staged processing allowing to first ascertain that parts 2 can be grasped by the picking head of a robot - referred to hereafter as “gripper” 176, as visible in Fig.11 - and then defining an optimized picking itinerary between all pickable parts 2A.

[0053] In fig. 1 , there is only one pickable part 2A highlighted in plain black. This part is supposed to define the part among all parts 2 of the bin 10 that has been chosen as an output of the third step (03), i.e. the selection operation. The fourth step (04) consists in the actual picking operation done by the robot, and the fifth step (05) then to flush or respectively empty the bin, possibly with the help of a spill-over mechanism involving the tilting of the bin 10 containing remaining parts. In this figure, the displacing apparatus 11 has been schematically illustrated with respect to his function only, i.e. to move the adjustable bottom part 10A in order to set its height level. This displacing apparatus 11 can take several structural forms though, including the ones illustrated in the next figures, involving pistons. It can be appreciated that other embodiments could be foreseen for these functional elements without departing from the scope of the present invention, such as scissors, or even, in the simplest case, cable or pulleys. The common points to all these displacing apparatuses 11 is that they are coupled to a control unit 14, consisting e.g. of an electronic controller, and that this control unit 14 is arranged for driving this displacing apparatus 11 based on data acquired from sensors 12 of the smart bin picking system 1. In other words, the control unit 14 is meant to implement the smart driving logic of the bin picking system so that the efficiency of the picking process is always optimized thanks, among others, to the automatic setting of the adjustable bottom of the bin 10 so that there is always a pickable part 2A available for the robot.

[0054] The Figures 2A and 2B show a preferred embodiment for the realization of bin part of the smart bin picking system 1 according to the present invention, in which the bin 10 is fully integrated in a box 15 further encompassing a set of cameras (i.e. the subset of visual sensors 120, whose only insertion slots 152 are visible in Fig 2A and which will be yet visible later in Fig. 4) on top of it. In the framework of this embodiment, the lateral side walls of the bin 10B are also fully integrated inside the box 15 and the inside of these walls are shown in Fig.2A. The adjustable bottom portion 10A is highlighted in plain black. This element can travel between a first position P1 as illustrated in Fig 2A, corresponding to a maximal depth, and a second position P2, illustrated in contrast in Fig 2B, corresponding to a minimal depth for the inside of the bin 10. The displacement of the adjustable bottom portion 10A is carried out in the second step (02) introduced previously while discussing Fig.1 , thereby minimizing the need for significant moves of the robot gripper, for which a preferred embodiment is illustrated in Fig. 11.

[0055] In the configuration illustrated in Fig 2B, the adjustable bottom portion 10A can be levelled with the top of the box 15 and hence go beyond the insertion slots 152 that are foreseen for the cameras. In that case, these insertion slots 152 shall be closed by glass or translucent walls. Preferably, in that second position P2, the adjustable bottom portion 10A remains below the cameras though, just like in the embodiment illustrated in Fig. 4 when relating to a fully integrated solution in a box 15 or in the embodiment illustrated in Fig.10 when relating to single bins 10 meant to be placed on a conveyor 18.

[0056] As it can be appreciated from the figures 2A & 2B, according to this preferred embodiment the adjustable bottom portion 10A of the bin 10 is a rectangular levelling plate, whose corners C are set forth in Fig.2B. However, the shape of this element can take various geographical forms, including a regular octagonal shape, or a circular shape. A preferred embodiment involving chamfered edges is shown in subsequent figures. The geometrical shape is also not necessarily totally comprised within a horizontal plane; it can be slightly inwardly curved in order to move parts 2 located at the periphery of the adjustable bottom portion 10A towards the inside, i.e. the center of the bin 10, and thus facilitate the gripping operation.

[0057] In the framework of the present invention, the sensors 12 include a subset of at least one, and preferably several visual sensors 120 arranged in an annular space (S) - illustrated and discussed later in detail further in view of Fig. 5 - surrounding the cylindrical or parallelepiped shape extending vertically over the perimeter of the adjustable bottom portion 10A. According to the preferred embodiment for the present invention wherein the bin 10 is fully integrated in a box 15, this annular space S is designed as a halo-shaped space, thereinafter simply referred to as halo 151 , that is here of a rectangular shape, but may also be of any annular shape, including e.g. an oval shape. As illustrated in Fig.3, the subset of visual sensors 120 consist of several cameras arranged in the halo 151 fitted on top of the box 15 receiving the bin 10. This way, an easy and effective mounting solution for the cameras is provided. Preferably, the halo 151 further includes an illuminating system 16, so simultaneous mounting of both cameras and associated lights is made possible through a simplified modular solution.

[0058] In the illustrated embodiment, the cameras (visual sensors 120) are mounted on a support and placed inside halo slots 152. In the gaps 155 between each camera, lighting elements such as LEDs 160, preferably arranged as LED bars, can be placed, either at the same level in order to precisely fill in the gaps 155 and not require any additional space, or right above the halo 151. Preferably, the illuminating system 16 thus comprises LED bars 160 arranged at regular intervals in order to further enhance the illumination properties and hence further improve optical detection capabilities of the cameras, still without entering any space obstructing movements of a robot for subsequent gripping / grasping operation of parts located inside the bin 10.

[0059] According to another preferred embodiment for the present invention illustrated in Fig. 4, a box 15 receives a bin 10, that is this time not fully integrated inside the box 15, in the sense that the side walls 10B of the bin 10 are not merged with the lateral walls of the box 15. In other words, the bin 10 is a fully modular bin 10 that can be placed on a drawer 154 that can be pulled out of the box 15 through a lateral opening 153 thereof, for the sake of manual loading, as in first step (01 ), and possibly also unloading purposes. The four side walls 10B surround the hidden adjustable bottom portion 10A (too low and hence not visible on this figure) which is still supposed to be movable so as to take different height levels. Yet in order to do so, the drawer 154 preferably has a hollow shape in order to let a central piston pass through and push up the adjustable bottom portion 10A when the drawer 154 is fully inserted inside the box 15. In that case, the configuration can be the same as the one discussed later further in view of Figure 8A-8B and Fig.10.

[0060] On the upper part of the box, the slots 152 foreseen for the cameras and the gaps 155 between all these slots are arranged in a similar fashion as for the halo 151 of previous Fig. 3. Therefore, the annular space S - highlighted in next Fig.5 - in which the cameras, i.e. the visual sensors 120, are arranged, is located above all top edges T of every side wall 10B of the bin 10, so that, if the second position P2 for the adjustable bottom portion 10A does not vertically these top edges T, then the cameras always remain above it.

[0061] Fig.5 shows a preferred embodiment for the realization of the present invention, involving an adjustable bottom portion 10A still arranged as a levelling plate, but having a slightly octagonal shape due to chamfered edges E instead of the corners C of the rectangular shape of the previous figures (such as e.g. Figs 2A-2B). This figure best shows the annular-shaped space S, in which the cameras used as visual sensors 120 are placed. In this figure the visual sensors 120 may account for integrality of the set of sensors 12, and the chamfered edges E are connecting each of the side walls 10B. Such a configuration allows to better draw the parts 2 toward the center of the bin 10, and also allows to avoid parts being pinched or stuck in the corners.

[0062] Still in Fig. 5, the perimeter P of the adjustable bottom portion 10A is highlighted, here with an octagonal shape defining an inner space inside which no cameras are supposed to be placed. Although the vertical dimension cannot be represented on this two-dimensional figure, it defines the horizontal section of a vertical space which is surrounded by the annular space S. As it can be appreciated from Fig.5, four LEDs 160 are arranged at regular spacing intervals between cameras, and these LEDs 160 can be either integrated in the lighting system 16 of a halo 151 just like the one illustrated in the previous figure.

[0063] Figures 6A and 6B show a similar configuration for modular bins 10 of the smart bin picking system 1 according to another preferred embodiment the present invention, in which the bins 10 are not necessarily fully integrated in a box 15, but may be placed on a conveyor system (as explained later further in view of figure 10). Just like in Figs 2A & 2B, the adjustable bottom portion 10A is highlighted in plain black, and it can travel between a first position P1 [shown in Fig. 6A], corresponding to a maximal depth DMax, and a second position P2 [shown in Fig. 6B], corresponding to a minimal depth DMin for the inside of the bin 10.

[0064] Figures 7A & 7B shows a bin 10 suitable for the smart bin picking system according to the present invention, according to a preferred embodiment involving a displacing apparatus made of at least three vertical pistons whose tips are arranged at the periphery of a leveling plate used as adjustable bottom portion 10A. These at least three vertical pistons are arranged for vibrating and tilting the adjustable bottom portion 10A, so that it can reshuffle the 6D position of the parts inside the bin 10, and in particular change their orientation (in 3 dimensions with respect to rotational axis) and positioning inside the bin 10 (in another three dimensions with respect to translational axis) if necessary. In the illustrated embodiment, there are four pistons (a first vertical piston 110A, a second vertical piston 110B, a third vertical piston 110C, and a fourth vertical piston 110D, whereby the first vertical piston 110A and the fourth vertical piston 110D are shown according to a sagittal section, since only half of the bin 10 is shown in Fig. 7B). It can be appreciated that moving the parts and / or changing their 3D orientation inside the bin 10 could be done, irrespective of the number of pistons used, through vibrating of the leveling plate only, possibly with a single central piston only.

[0065] All the four pistons (110A, 110B, 110C, 110D) pass through corresponding holes of a fixed bottom portion 110, i.e. a first hole 101 A, second hole 101 B, third hole 101 C, and fourth hole 101 D in order to tilt and shake the levelling plate used as adjustable bottom portion 10A according to the needs. These corresponding holes (101 A, 101 B,101 C,101 D) are arranged near the corners C of the parallelepipedal bin 10 in order to best leverage the sought tilting orientation.

[0066] Figs 8A & 8B show an alternative embodiment for moving the adjustable bottom portion 10A of the bin 10, involving only a single central piston 110, that is illustrated on Fig. 8B. Such a variant embodiment is simpler to implement because it does not need the alignment with several smaller holes. Figure 8A shows, similarly to Fig 7A, bottom corners C of the bin 10 of a parallelepiped shape, that no more require a fixed bottom, that is fully replaced by the adjustable bottom portion 10A. On top of the bin10, the top edges T of the side walls 10B are shown in Fig. 8A, indicating the preferred minimal height level for arranging cameras, if no translucent walls are to be used, and if the cameras are intended to always seat on a higher ground than the parts 2, irrespective of the position of the levelling plate (or any adjustable portion 10A), to be able to best monitor their exact positioning.

[0067] Fig. 9 shows a preferred embodiment for the adjustable bottom portion 10A for the smart picking system 1 according to the present invention, including pins 100 of preferably conical of pyramidal shape. These pins 100 may be arranged directly on a level plate used as an adjustable bottom portion 10A, or even more preferably on a modular mat that can be made of a different material and replaced independently from the level plate itself as a wearing element. The goal of these pins 100 is to avoid rolling of parts 2, here represented with a spherical shape for the sake of simplification, when displacing the levelling plate and / or slightly tilting or vibrating it, thus keeping their location steady, and hence just working on their orientation on levelling plate.

[0068] Fig. 10 shows another preferred embodiment for the smart bin picking system 1 according to the present invention, involving modular bins 10 of utmost simplicity just like the ones illustrated in previous figures 6A-6B, and that are integrated on a conveyor belt 18. In such a configuration, the displacing apparatus 11 may be arranged as a central vertical piston 110 arranged below the conveyor system 18, and each of the bins 10 can be moved along a translational direction M.

[0069] As it can be appreciated further in view of Fig. 10, the subset of visual sensors 120 consists here of several cameras mounted on a fixed framework 13 enclosing the central bin 10. Although the cameras could be mounted on the fixed framework directly, they are here positioned on an annular support 131 of rectangular shape protruding inside the framework in order to be positioned slightly closer to the bin still without obstructing any space right above it. The adjustable bottom portion 10A is currently in its uppermost vertical position - corresponding to the second position P2 illustrated before, e.g. in Fig 6B - after a displacement in the second step (02) in order to make sure that at least some parts can be picked by the robot. Each of the bins 10 are moved along the translational direction M in order to be placed above the central vertical piston 110 so that the adjustable bottom portion 10A can be moved in order to simplify the picking operation by a robot (not shown). The first bin 10 (before picking operation) and the third bin (after picking operation) are each shown with their adjustable bottom plate 10A at the lowest level - corresponding to the first position P1 illustrated before, e.g. in Fig 6A - as opposed to the second bin 10 currently processed inside the fixed framework 13. The goal of this figure is to emphasize the fact that the smart bin concept proposed in the framework of the present invention can be easily integrated in a conveyor system 18 with which the smart bin picking system 1 is fully compliant.

[0070] As it explained throughout the description, the smart bin picking system 1 according to the present invention preferably further comprises an articulated picking robot 17 fitted with a gripper 176, and the control unit 14 is arranged to drive the displacement apparatus 11 based further on operational characteristics of said picking robot 17, such as its current position, available degrees of freedom, overall length and relative length of each of its segments, etc. possibly using reverse kinematics.

[0071] Fig. 11 illustrates a preferred embodiment for such a picking robot 17 to be used in the framework of the present invention. The picking robot 17 is mounted on a base 170, that is slightly elevated with respect to the lowest adjustable bottom portion 10A of the bin 10, and possibly even with the bottom of the working zone Z (not illustrated in this Figure but shown in Fig.1 ), corresponding the second position P2 of the adjustable bottom portion 10A. The robot has a first arm 171 having a first length L1 and second arm 172 of a second length L2; the ratio between these two lengths L2 / L1 is chosen to be at least superior or equal to two, so that the movements of the robot are the least intrusive inside the bin 10, while remaining as much as possible at a minimal depth level inside the bin 10. On the one hand, and the range of movement of the robot is thereby kept to a minimal level.

[0072] In the proposed configuration illustrated in Fig. 11., the first arm 171 is articulated via a first joint 173 to the base 170, the first joint consisting in a double pivotal joint according to two rotational degrees of freedom perpendicular to one another (i.e. the first rotational axis 173A of the first joint and the second rotational axis 173B of the first joint 173). Similarly, the second arm 172 is articulated via a second joint 174 to the first arm 171 , also via a double pivotal joint according to two rotational degrees of freedom perpendicular to one another (i.e. the first rotational axis 174A of the second joint and the second rotational axis 174B of the first joint 174, whereby the second rotational axis actually consists of the longitudinal axis of the second arm 174). Finally, the gripper 176 is articulated over a third joint 175 with respect to said second arm 172 still via a double pivotal joint according to two rotational degrees of freedom perpendicular to one another (i.e. the first rotational axis 175A of the third joint and the second rotational axis 175B of the third joint 174, whereby the second rotational axis actually consists of the longitudinal axis of the gripper 176). The gripper is further equipped with an additional visual sensor 121.

[0073] As shown on Fig. 11 , a set of cameras (i.e. visual sensors 120) are disposed around the top edges T of the side walls 10A, and once parts 2 have been fed into the bin 10, the displacing apparatus 11 is driven in a second step (02) based on data acquired by the sensors 12, comprising the visual sensors 120, by the control unit 14 - not shown in this figure by schematically illustrated in figure 1 - so that at least one part 2 within said bin 10 can lie in a predefined working zone Z for the picking robot 17. Then, after a selection operation - referred to as third step (03) and also schematically illustrated in Fig.1 - based on data acquired by said subset of visual sensors 120, the robot 17 can also be actuated by the control unit 14 in a subsequent fourth step (04) to perform the gripping operation (04) according to an optimized picking itinerary.

[0074] It can be appreciated that, in such a configuration, where the gripper 176 is further provided with an additional visual sensor 121 , the data acquired by this additional visual sensor 121 can be used in any of the second step (02) or said third step (03), or a combination of these steps. In case it is used in the second step (02) already, it would mean that it the provided improved resolution yield by all available visual sensors of the smart bin picking system is helping make a prompt decision on the actuation of the adjustable bottom part 10A to ensure that pickable parts can be found by the robot in the working zone Z. Otherwise, if the additional information provided by the additional visual sensor 121 of the gripper 176 would no longer be used to actuating the adjustable bottom part 10A, but only in a subsequent step of selecting among available parts for picking, thus offering a staged-processing scheme optimized for defining a efficient picking itinerary while minimizing computational resources consumption.

[0075] The present invention thus describes a solution for a smart bin picking system with overall enhanced efficiency in terms of speed and resolution. Such a solution also imposed lower constraints on the robot, which can have an overall shorter length L (L being defined as L = L1 + L2 the first length L1 of a first arm 171 of the robot 17 and a second length L2 of the second arm 172 of the robot in the configuration of Fig.11 ) and whose range of motion can be limited while performing the picking operations.

Claims

Claims1 . Smart bin picking system (1 ) comprising a bin (10) fitted with at least one adjustable bottom portion (10A), and displacing apparatus (11 ) arranged to move said adjustable bottom portion (10A) between a first position (P1 ) where the bin (10) has a maximal depth (Diviax), and a second position (P2) where the bin (10) has a minimal depth (Di iin), wherein said smart bin picking system (1 ) further comprises a set of sensors (12) including a subset of at least one visual sensor (120) arranged within an annular space (S) surrounding any vertical projection of the perimeter (P) of said adjustable portion (10A) on any horizontal plane, and wherein said sensors (12) and said displacing apparatus (11 ) are coupled through a control unit (14), said control unit (14) driving said displacing apparatus (11 ) based on data acquired by said sensors (12).

2. Smart bin picking system (1 ) comprising a bin (10) according to claim 1 , wherein said annular space (S) is placed above the top edges (T) of every lateral wall (10B) of said bin (10).

3. Smart bin picking system (1 ) according to claim 1 or 2, wherein said subset of visual sensors (120) consists of several cameras arranged in a halo (151 ) fitted on top of a box (15) receiving said bin (10).

4. Smart bin picking system (1 ) according to claim 3, wherein said halo (151 ) further includes an illuminating system (16).

5. Smart bin picking system (1 ) according to claim 4, wherein said illuminating system (16) comprises LEDs (160) arranged at regular intervals.

6. Smart bin picking system (1 ) according to claim 3 to 5, wherein said box (15) further comprises a lateral opening (153) and a drawer (154) arranged for supporting said bin (10) inside said box (15) and moving it outside said box (15).

7. Smart bin picking system (1 ) according to any of the claims 1 to 6, wherein said displacing apparatus (11 ) is made of at least three verticalpistons whose tips are arranged at the periphery of a leveling plate used as adjustable bottom portion (10A), said at least three vertical pistons being further arranged for vibrating and tilting said adjustable bottom portion (10A).

8. Smart bin picking system (1 ) according to claim 1 , wherein said subset of visual sensors (120) consists of several cameras mounted on a fixed framework (13) enclosing said bin (10).

9. Smart bin picking system (1 ) according to claim 8, wherein said displacing apparatus (11 ) is a central vertical piston (110) arranged below a conveyor system (18).

10. Smart bin picking system (1 ) according to any of the previous claims, wherein said adjustable bottom portion (10A) is a chamfered leveling plate.11 . Smart bin picking system (1 ) according to any of the previous claims, wherein said adjustable bottom portion (10A) has pins (100).

12. Smart bin picking system (1 ) according to any of the previous claims, wherein said smart bin picking system (1 ) further comprises an articulated picking robot (17) fitted with a gripper (176), and wherein said control unit (14) is arranged to drive said displacement apparatus (11 ) based further on operational characteristics of said picking robot (17).

13. Smart bin picking system (1 ) according to claim 12, wherein said picking robot (17) is mounted on a base (170) and has a first arm (171 ) articulated via a first joint (173) to said base (170), a second arm (172) articulated via a second joint (174) to said first arm (171 ), wherein said gripper (176) is articulated over a third joint (175) with respect to said second arm (172), and wherein the ratio between a first length (L1 ) of said first arm (171 ) and a second length (L2) of said second arm (172) is at least 2: 1 .

14. Smart bin picking system (1 ) according to claim 12 or 13, wherein said control unit (14) is arranged for, after a first step (01 ) of feeding parts (2)into said bin (10), driving said displacing apparatus (11 ) in a second step (02) based on data acquired by said sensors (12) so that at least one part (2) within said bin (10) lies in a predefined working zone (Z) for said picking robot (17), and for performing, in a third step (03), a selection operation of a pickable part (2A) based on data acquired by said subset of visual sensors (120).

15. Smart bin picking system (1 ) according to claim 14, wherein said gripper (176) is further provided with an additional visual sensor (121 ), and wherein data acquired by said additional visual sensor (121 ) are used in said second step (02) and / or said third step (03).

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