WO2022264181A1

WO2022264181A1 - Apparatus for automatically wrapping a load with a film of stretch material

Info

Publication number: WO2022264181A1
Application number: PCT/IT2022/050171
Authority: WO
Inventors: Luca Roselli; Gianluca Paci
Original assignee: Atlanta Stretch S.P.A.
Priority date: 2021-06-14
Filing date: 2022-06-14
Publication date: 2022-12-22
Also published as: EP4370426A1; IT202100015509A1

Abstract

The apparatus for automatically wrapping a load with a film of stretch material comprises a guide carriage (2) comprising moving means (3), operable to move said guide carriage (2) around a load to be wrapped; a column (8) associated with said guide carriage (2) and adapted to carry a reel of said film of stretch material, said reel being rotatable to release, in operation, said stretch material around said load to be wrapped; a control unit.

Description

APPARATUS FOR AUTOMATICALLY WRAPPING A LOAD WITH A FILM OF STRETCH

MATERIAL Technical field

[01] The present invention relates to a method and an apparatus for automatically wrapping a load with a film of stretch material.

Background of the invention

[02] In the technical sector of the packaging of loads comprising one or more articles, the loads are generally placed in contact with their ends with a contact roller, configured to engage the profile of the articles to be wrapped, producing a reaction force that causes the motor unit to follow the perimeter of the articles without further turning towards them.

[03] An example of the above type of apparatus is illustrated in the international application WO2012/153248. The apparatus includes a carriage equipped with a pair of directional wheels arranged on a support platform made up, for example, of a pallet.

[04] Articles are generally wrapped with a film of wrapping material, such as a stretch material, to form a single, larger package. The packaging formed in this fashion is more easily handled and transported.

[05] The wrapping operation takes place through the use of an apparatus, which is moved along the perimeter of the palletized articles, and unwinds the film of wrapping material from a reel so as to make a packaging, following a predetermined number of turns made around the pallet.

[06] A type of wrapping apparatus includes a guide carriage that supports a reel of wrapping material rotated in order to unwind the material, in operation. The carriage comprises moving means and a motor unit, adapted to operate the moving means to exert a propelling force on the carriage. Associated with the carriage is a laterally projecting arm, to allow variation of the direction of travel of the carriage. A feeler arm is connected to one of the directional wheels which performs the function of enabling the change in the direction of travel according to the profile of the load to be wrapped.

[07] A problem complained about in relation to the aforementioned type of apparatus is the use of a feeler arm that enables following the profile of the palletized products but cannot enable wrapping a load having an irregular shape along a direction orthogonal to the load support surface, for example a load having one or more portions projecting outwards, at a height different from that at which the feeler arm operates. In fact, in this case, the feeler arm is unable to detect the protruding portion and a collision of the apparatus with the load may occur.

[08] This drawback also occurs if the load is dynamic, that is, if it is subject to changes in shape over time which are not detected by the feeler arm. For example, the load can include one or more movable portions that can give rise to protruding portions of the load, located at a different height from that at which the feeler arm operates.

[09] In order to overcome this problem, wrapping apparatuses have been developed that do not require the use of the feeler arm.

[10] Patent EP 3331 768 discloses an apparatus for wrapping a load, which includes a carriage, associated with guide means, and a column, mounted on the carriage, which carries a reel of plastic material. The apparatus includes sensor means to detect surfaces and/or edges of the load, along a direction substantially orthogonal to the plane of the load; the sensor means is designed to send signals to a control unit which are analyzed to define a peripheral contour of maximum overall dimensions of the load and calculate, based on the contour, a wrapping path of the apparatus around the load. The sensor means comprises ultrasonic sensors or optical time-of-flight sensors which are arranged on the carriage and/or on the column. The sensor means can also comprise optical image sensors such as, for example, a video camera or a laser scanner sensor.

[11] Although apparatuses have been developed that carry out the wrapping without the aid of a feeler arm, the need to find improvements that carry out autonomously the automatic wrapping of a load with a film of wrapping material is nevertheless felt.

Disclosure

[12] The aim of the present invention is to solve the mentioned problems, devising an apparatus that permits to easily wrap, autonomously, a load with a film of wrapping stretch material.

[13] A further object of the present invention is to provide an apparatus which allows a film of a wrapping material to be wrapped around a load having an irregular shape, in particular along a vertical direction.

[14] A still further object of the present invention is to provide an apparatus that allows obstacles to be bypassed effectively.

[15] A further object of the present invention is to devise an apparatus that guarantees optimum safety.

[16] A further object of the invention is to provide a wrapping apparatus of simple construction and functional conception, having reliable operation, versatile use, as well as relatively low cost.

[17] The aforementioned purposes are achieved, according to the present invention, by the apparatus of claim 1 and by the method of claim 9.

[18] The apparatus for automatically wrapping a load with a film of stretch material includes a guide carriage comprising moving means, operable to move said guide carriage around a load to be wrapped; a column, associated with said guide carriage, adapted to carry a reel of stretch material, said reel being rotatable to release, in operation, said stretch material around said load to be wrapped. [19] The apparatus comprises radar sensor means associated with said guide carriage and/or said column, said radar sensor means being configured to detect instant by instant data relating to the distance of said guide carriage from at least one obstacle.

[20] Preferably, said radar sensor means is of the 60 GHz pulse type.

[21] The apparatus also comprises a control unit configured to receive said data from said radar sensor means and to calculate, based on said data, a predetermined steering angle that said guide carriage must follow.

[22] In practice, said data detected by said radar sensor means are processed by said control unit in real time to maintain the distance of said guide carriage from said load to be wrapped within a predetermined extent range.

[23] Preferably, said range is determined according to the characteristics of the load to be wrapped.

[24] Preferably, said obstacle comprises said load to be wrapped and may include a further obstacle present in the working environment of said apparatus.

[25] Preferably, said radar sensor means is configured to detect data relating to the distance of said guide carriage from said obstacle at least along a first direction transverse to said guide carriage.

[26] Preferably, said radar sensor means comprises at least a first radar sensor having a field of view oriented along said first direction, towards said load to be wrapped. Said at least one first sensor allows, therefore, to measure the distance between the carriage and the load along the first direction, ensuring the maintenance of a safety distance from the load to avoid collisions. Consequently, the apparatus can carry out the wrapping operation by safely rotating around the load.

[27] Preferably, said radar sensor means configured to detect data relating to the distance of said guide carriage from said obstacle along a first direction, transversal to said guide carriage, comprises at least a first and a second radar sensor arranged side by side and oriented towards said load to be wrapped.

[28] Preferably, said first and second radar sensors placed side by side and oriented towards said load to be wrapped are arranged at a height such as to detect at least an upper part of a support device of the load to be wrapped and/or a lower part of the same load to be wrapped placed on the said support device.

[29] Preferably, said radar sensor means is configured to detect data relating to the distance of said guide carriage from an obstacle at least along a second substantially vertical direction.

[30] Preferably said radar sensor means comprises a second radar sensor having a field of view oriented along said second direction, upwardly.

[31] Advantageously, said radar sensor means is configured to detect data relating to the distance of said guide carriage from an obstacle at least along said first direction, transverse to said guide carriage, and along said second direction, substantially orthogonal to said first direction.

[32] Preferably said second direction is substantially vertical.

[33] Preferably said radar sensor means comprises at least a first radar sensor having a field of view oriented along said first direction, towards said load to be wrapped, and at least a second radar sensor having a field of view oriented along said second direction, upwardly. In this way, the sensor means provides data relating to the height of the obstacle and the distance of the carriage from the obstacle along the first direction, allowing the obstacle to be identified promptly and effectively.

[34] According to one aspect of the invention, said radar sensor means is further configured to detect data relating to the distance of said guide carriage from an obstacle at least along a third direction, said third direction being substantially orthogonal to said first direction and said second direction.

[35] Preferably, said radar sensor means comprises at least a third radar sensor having a field of view oriented along said third direction. This third sensor performs the function of supporting the obstacle avoidance maneuvers.

[36] Preferably said radar sensor means is mounted at a lateral surface of said guide carriage adapted to be turned, in the operational phase, towards said load to be wrapped.

[37] Preferably said apparatus comprises a support device associated with a lateral surface of said guide carriage, adapted to support said radar sensor means.

[38] Preferably said support device is movable with respect to said guide carriage. More particularly, said support device may be translated with respect to said lateral surface of said carriage, so as to adjust the position of the radar sensor means.

[39] According to one aspect of the invention said support device comprises a connecting element, connected to said guide carriage.

[40] Preferably said support device comprises one or more attachment elements that are fixed to said connecting element, said attachment elements being adapted to support said radar sensor means.

[41 ] Preferably said at least one third radar sensor is mounted on a front surface of said support device.

[42] Preferably said first radar sensor and said second radar sensor are mounted on a side surface of said support device, facing said load.

[43] Preferably said radar sensor means is arranged at a height between the floor and the height of the surface of said guide carriage arranged, in operation, upwardly.

[44] Preferably said apparatus comprises a steering assembly, connected to said handling means, said steering assembly being controlled by said control unit based on said data transmitted by said radar sensor means. [45] According to one aspect of the invention, said apparatus comprises a plurality of radar sensors arranged along said column of said apparatus.

[46] Preferably said radar sensors have their respective fields of view oriented along said third direction.

[47] It is also an object of the present invention a method for automatically wrapping a load with a film of stretch material.

[48] The method comprises the step of arranging an apparatus for automatically wrapping said load with a film of stretch material equipped with radar sensor means.

[49] The method involves starting to wrap said film of stretch material around said load, and, at the same time, detecting instant by instant, by means of said radar sensor means, data relating to the distance from at least one obstacle.

[50] Preferably, the load to be wrapped is understood as an obstacle but it can also be a further obstacle present in the work environment, for example an object next to the load.

[51] This data is then transmitted to a control unit and the direction of travel of said apparatus around said load to be wrapped is controlled by said control unit.

[52] The above steps are repeated until a wrapping cycle is completed.

[53] Preferably said control unit is configured to command a predetermined steering angle that said apparatus must follow.

[54] Preferably said control unit is configured to control that the trajectory of said apparatus is within a region comprised between a predefined minimum distance value and a maximum distance value from the load to be wrapped.

Description of drawings

[55] The details of the invention will be more fully appreciated from the detailed description of a preferred embodiment of the apparatus for automatically wrapping a load with a film of stretch wrapping material according to the invention, illustrated by way of example in the accompanying drawings, wherein:

Figures 1 and 2 are respectively perspective views of the apparatus for wrapping a load with a film of stretch material according to the present invention;

Figure 3 is a perspective view of the apparatus from a different angle;

Figure 4 is a side view of the apparatus;

Figure 5 is a perspective view of the apparatus according to a different embodiment;

Figure 6 is a perspective view of the same apparatus illustrated in Figure 5 from a different angle;

Figures 7, 8 and 9 are respectively a side view, a front view and a bottom view of the apparatus illustrated in Figure 5;

Figure 10 is a perspective view of a different embodiment of the apparatus;

Figure 11 is a perspective view from a different angle of the apparatus illustrated in Figure 10;

Figure 12 is a side view of the apparatus illustrated in Figure 10.

Description of embodiments of the invention

[56] With reference to these figures, the numeral 1 indicates the apparatus for automatically wrapping a load with a film of stretch wrapping material according to the present invention. The load may comprise one or more products arranged on a support, for example of the type of a pallet.

[57] The apparatus 1 comprises a guide carriage 2 equipped with moving means 3 that can be operated to move the carriage 2 itself around a load to be wrapped. The moving means 3 comprises a pair of traction wheels 30, rotatable by a drive member, not visible in the figures. The moving means 3 also comprises a pair of steering wheels 31 , arranged on an opposite side of the carriage 2 with respect to the traction wheels 30.

[58] The steering wheels 31 are connected to a steering assembly 4 which is operable, upon actuation of a relative motor assembly, to direct the steering wheels 31 according to a predetermined steering angle. More particularly, the steering wheels 31 are mounted on a substantially horizontal axle which is associated with the steering assembly 4. The steering assembly 4 is not further described, as it is known per se.

[59] It is possible that the steering assembly 4 can also be operated manually by an operator, by means of a gripping member 5 connected to the steering assembly 4, for example in case the operator wishes to manually position the apparatus 1 before a wrapping operation.

[60] The motor assembly relating to the steering assembly 4 is controlled by a control unit based on the data received from radar sensor means, as explained further below.

[61] The guide carriage 2 comprises a frame 6 to which a safety member 7 is connected at the front. The safety member 7 can be made up of a bar having a curved surface, preferably of a hemispherical or semi-elliptical shape, which is connected, at opposite ends, to the frame 6. The safety device 7 performs the function of cushioning any impacts of the apparatus 1 with the obstacles present in the work environment.

[62] The guide carriage 2 is associated with a support column 8 that develops along a substantially vertical direction. The support column 8 is adapted to carry at least one reel of a stretch wrapping material, not shown in the figures; said reel is movable, in a known manner, along the column 8. The reel is movable on command of special actuating means, not shown. More in detail, the reel is mounted on a base 9 which is moved in a translational motion along the column 8, by means of said actuating means.

[63] The reel is adapted to be rotated by a drive assembly to unwind the wrapping material, in operation. The wrapping material is preferably a plastic material, for example a stretch plastic material.

[64] According to the present invention, the apparatus 1 comprises radar sensor means 10 associated with the guide carriage 2, which are configured to detect instant by instant data relating to the distance of the guide carriage 2 from at least one obstacle, not represented. Preferably said radar sensor means 10 is of the 60 GHz pulse type.

[65] This obstacle consists of the load to be wrapped as well as any additional obstacles that may be present along the trajectory of the apparatus. For simplicity, only one obstacle will be mentioned in the following description.

[66] The radar sensor means 10 is configured to detect instant by instant data relating to the distance of the guide carriage 2 from an obstacle at least along a first direction X transversal to the guide carriage 2. The first direction X, transversal to the guide carriage 2, is intended as a direction transversal with respect to a lateral surface 20 of the guide carriage 2.

[67] Preferably, the radar sensor means 10 is configured to detect data relating to the distance of the guide carriage 2 from an obstacle at least along a first direction X transverse to the guide carriage 2 and at least along a second direction Z orthogonal to the first direction X. The second direction Z is substantially vertical.

[68] Preferably, the radar sensor means 10 is also configured to detect data relating to the distance of the guide carriage 2 from the obstacle along a third direction Y, which is substantially orthogonal to the first direction X and to the second direction Z.

[69] Said three detecting directions X, Y, Z substantially correspond to the directions defined by the oriented axes of a Cartesian tridimensional reference system.

[70] Furthermore, the radar sensor means 10 is characterized, in a way known in the art, by the visual field in which it operates. Therefore, detecting the data along a direction means that the visual field of the sensor is substantially oriented along said direction, as shown in Figures 2 and 5-12. The visual field of each sensor may be shown as a conical region defined by a specific detecting angle that defines the extent of the region.

[71 ] The radar sensor means 10 comprises at least a first radar sensor 11 , which is conveniently oriented to detect the data relating to the distance from an obstacle along the first direction X. The first radar sensor 11 is adapted to transmit electromagnetic signals towards the load along said direction X and to receive the signals reflected by the load.

[72] Preferably, said radar sensor means 10 configured to detect data relating to the distance of said guide carriage 2 from said obstacle along a first direction X, transversal to said guide carriage 2, comprises at least a first and a second radar sensor 11 arranged side by side and oriented towards said load to be wrapped.

[73] Preferably, said first and second radar sensors 11 placed side by side and oriented towards said load to be wrapped are arranged at a height such as to detect at least an upper part of a support device of the load to be wrapped and/or a lower part of the same load to be wrapped placed on the said support device.

[74] The radar sensor means can also comprise a plurality of first radar sensors 11 facing the load to be wrapped, for example three radar sensors 11 , as shown in Figures 1-4. The number of radar sensors involved can be different, depending on needs.

[75] The radar sensor means 10 can comprise furthermore at least a second radar sensor 12, which is oriented to detect data relating to the distance from an obstacle along the second direction Z, as shown in the Figures 5-9. In particular, the second radar sensor 12 is oriented so as to emit the electromagnetic signals along the second direction Z, upwardly, and to receive the signals reflected from any obstacle. In this way, the at least one second radar sensor 12 has the effect of detecting the height of the obstacle.

[76] In the embodiment illustrated in Figures 5-9, the apparatus 1 comprises a pair of first radar sensors 11 and a pair of second radar sensors 12. It is obviously possible that the number of radar sensors used is different, depending on the needs.

[77] The redundancy of radar sensors ensures greater accuracy of measuring distance values from an obstacle.

[78] Each first radar sensor 11 may be a FMCW (Frequency Modulated Continuous Wave) radar sensor, which is a type of continuous wave radar sensor, or a pulse radar sensor.

[79] Each second radar sensor 12 may be an FMCW radar sensor or a pulse radar sensor or a doppler radar sensor.

[80] According to a further embodiment, illustrated in Figures 10-12, the radar sensor means 10 further comprises at least a third radar sensor 13 that is oriented so as to detect the distance data along the third direction Y. The third radar sensor 13 performs the function of supporting obstacle avoidance maneuvers.

[81 ] The radar sensor means 10 is mounted at an outer side surface 20 of the guide carriage 2 facing the load, in operation.

[82] Preferably, the radar sensors 10 are mounted on a support device 14 associated with the guide carriage 2, in particular mounted at the aforementioned lateral surface 20 of the guide carriage 2.

[83] The radar sensors 10 are arranged at a height between the floor and the height of the surface of the guide carriage 2 arranged upwardly in operation.

[84] The support device 14 comprises a connecting member 15, associated with the guide carriage 2, and at least one pair of attachment members 16 fixed to the connecting member 15. The radar sensors 10 are arranged on the attachment members 16, for example a radar sensor is mounted on each attachment member 16.

[85] The connecting member 15 protrudes for a portion with respect to a front surface of the carriage 2 to allow optimal positioning of the first and second radar sensors 11, 12. In this regard, it is noted that the mounting position of the first radar sensors 11 and the second radar sensors 12 along a direction substantially parallel to the third direction Y affects the ability of the sensors to promptly detect an obstacle. In fact, if the relative visual fields of the radar sensors 11, 12 are positioned forwardly with respect to the front portion of the carriage 2, an obstacle placed on the progress trajectory of the apparatus 1 may be identified more quickly. The third radar sensors are mounted on a frontal portion of the support device 14.

[86] The connecting member 15 may be movably associated with the guide carriage 2 for regulating the distance from the connecting member 15 and from the carriage and, therefore, for enabling the arrangement of the radar sensors 10 according to the needs.

[87] Preferably, the connecting member 15 has an elongated shape and can comprise several grooves for facilitating the anchoring of the attachment elements 16.

[88] It is possible to provide that the connecting element 15 and the attachment elements 16 are made in one piece.

[89] The attachment elements 16 have, each one, a flat shape and extend along a substantially vertical plane. Such a configuration of the attachment elements 16 is suitable for the first radar sensors 11 or third radar sensors 13.

[90] The attachment elements 16 may also shape a protruding portion with respect to the surface of the carriage 2, so that the second radar sensors 12 may be mounted, oriented along the second direction Z, upwardly. The attachment elements 16 are L-shaped, for example. The provision of a protruding portion allows the adjustment of the second radar sensors 12 along the direction X, such that the relative visual fields are oriented optimally.

[91] The data acquired by the radar sensors 10 are transmitted to the control unit, not visible in the figures, which is configured to receive said data and to control, based on the data, a predetermined steering angle that the apparatus must follow.

[92] The control unit processes the data transmitted by the radar sensors 10 and sends a control signal to the motor assembly associated with the steering assembly 4 so that the steering wheels 31 are moved according to a predetermined steering angle. The trajectory of the apparatus is processed in real time and is continuously updated as the control unit continuously processes the data transmitted by the radar sensors 10, updating the steering angle and, therefore, the trajectory to be followed moment by moment.

[93] The drive wheels 30 are instead rotated by the drive member, on command of the control unit, so as to maintain an approximately constant speed of the apparatus, in operation.

[94] It is of course possible to provide an embodiment of the apparatus according to which the control unit sends control signals to the drive member of the traction wheels 30 based on the data provided by the radar sensors 10. The control unit may also control the drive assembly of the reel and the actuating means, for example based on data provided by the radar sensors 10.

[95] The operation of the apparatus according to the present invention may be readily appreciated from the foregoing description.

[96] In a start-up phase of a wrapping cycle, the apparatus 1 is positioned near the load to be wrapped, for example manually by an operator.

[97] The drive assembly is activated, preferably by the control unit, to unwind the winding material from the reel and the wrapping begins.

[98] At the same time, the apparatus 1 is moved around the load, following a trajectory that is processed, moment by moment, by the control unit based on the data received from the radar sensors 10. More particularly, such sensors 10 detect data relating to the distance of the guide carriage 2 from an obstacle along the first direction X. The control unit processes the data, calculates the steering angle necessary to bypass the obstacle and commands the activation of the steering assembly 4 to move the steering wheels 31 by an angle equal to the calculated steering angle.

[99] In practice, the data detected by said radar sensor means 10 are processed by said real time control unit to maintain the distance of the guide carriage 2 from the load to be wrapped within a range of predetermined amplitude.

[100] In the event that the sensors 10 detect the data also along the second direction Z and the third direction Y, said data are likewise transmitted to the control unit and are used to calculate the steering angle.

[101] In the event that the second radar sensor 12 and the third radar sensor 13 do not detect the presence of an obstacle along the respective detection directions Z and Y, the control of the steering assembly 4 is carried out only on the basis of the data provided by the first radar sensor 11. The control unit therefore commands the steering assembly 4 to approach the apparatus to the load, if the measured distance is greater than a predetermined distance previously set, and to move away from the load, if the measured distance is lower than the predetermined distance.

[102] If, on the other hand, the second radar 12 sensor and the third radar 13 sensor detect an obstacle, the data of these sensors is assigned a higher priority from the control unit and the steering group 4 is commanded to get around the obstacle.

[103] The phases of detecting the data, of processing them to calculate the trajectory and command the movement means to follow the trajectory are repeated until the wrapping phase is completed.

[104] According to an embodiment of the invention, not shown in the figures, the radar sensors means 10 includes only a first radar sensor that has the relative field of view oriented along the first direction X.

[105] The first radar sensor is a radar with multiple antennas for triangulation, oriented along the first direction X, which allows the capture of data relating to the distance from the load along the entire load height. This first radar sensor is mounted on the lateral surface 20 of the guide carriage 2.

[106] The operation of the apparatus according to this embodiment provides that, once the apparatus is started to wrap the material around the load, the data captured by the first radar sensor are transmitted to the control unit, which processes them to command the steering maneuvers of the apparatus.

[107] According to a further embodiment, also not shown, the apparatus includes a plurality of radar sensors along the column 8. These radar sensors have their respective visual fields oriented along the third direction Y. The radar sensors transmit the data collected to the control unit that processes them to obtain information on the possible presence of obstacles.

[108] The apparatus described by way of example is susceptible to numerous modifications and variations according to the different needs.

[109] In the practical embodiment of the invention, the materials used, as well as the shape and dimensions can vary according to the needs.

[110] Should the technical features mentioned in any claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding of the claims and hence they shall not be deemed restrictive in any manner whatsoever on the scope of each element identified for exemplifying purposes by such reference signs.

Claims

1. An apparatus for automatically wrapping a load with a film of stretch material comprising a guide carriage (2), comprising moving means (3) operable to move said guide carriage (2) around a load to be wrapped; a column (8) associated with said guide carriage (2) and capable of holding a reel of said film of stretch material, said reel (8) being rotatable to release, in operation, said stretch material around said load to be wrapped; radar sensor means (10) associated with said guide carriage (2) and/or with said column (8), said radar sensor means (10) being configured to detect, instant by instant, data relating to the distance of said guide carriage (2) from at least one obstacle, said at least one obstacle comprising said load to be wrapped; a control unit configured to receive said data from said radar sensor means (10) and to calculate instant by instant, based on said data, a predetermined steering angle that said guide carriage (2) must follow.

2. The apparatus of claim 1 , wherein said radar sensor means (10) is configured to detect data relating to the distance of said guide carriage (2) from said obstacle at least along a first direction (X), which is transverse to said guide carriage (2), and said radar sensor means (10) comprises at least a first radar sensor (11 ) having a visual field oriented along said first direction (X), towards said load to be wrapped.

3. The apparatus of claim 2, wherein said radar sensor means (10) configured to detect data relating to the distance of said guide carriage (2) from said obstacle along a first direction (X), transversal to said guide carriage (2), comprises at least a first and a second radar sensor (11) arranged side by side and oriented towards said load to be wrapped.

4. The apparatus of claim 3, wherein said first and second radar sensors (11) placed side by side and oriented towards said load to be wrapped are arranged at such a height as to detect at least an upper part of a device for supporting the load to be wrapped and/or a lower part of the same load to be wrapped placed on said support device.

5. The apparatus of claim 1 , wherein said radar sensor means (10) is configured to detect data relating to the distance of said guide carriage (2) from said obstacle at least along a first direction (X), which is transverse to said guide carriage (2), and along a second direction (Z), which is substantially orthogonal to said first direction (X), said second direction (Z) being substantially vertical.

6. The apparatus of claim 5, wherein said radar sensor means (10) comprises at least a first radar sensor (11 ) having a field of view oriented along said first direction (X), towards said load to be wrapped, and at least a second radar sensor (12) having a visual field oriented upwards along said second direction (Z).

7. The apparatus of claim 6, wherein said radar sensor means (10) is configured to detect data relating to the distance of said guide carriage (2) from said obstacle at least along a third direction (Y), said third direction (Y) being substantially orthogonal to said first direction (X) and to said second direction (Z), and said radar sensor means (10) comprises at least a third radar sensor (13) having a field of view oriented along said third direction (Y).

8. An apparatus of any one of the preceding claims, wherein said radar sensor means (10) is mounted at a side surface (20) of said guide carriage (2) adapted to face, in operation, said load to be wrapped.

9. An apparatus of any one of the preceding claims, wherein it comprises a support device (14) associated with a side surface (20) of said guide carriage (2), capable of supporting said radar sensor means (10).

10. An apparatus of any one of the preceding claims, wherein it comprises a steering assembly (4), connected to said moving means (3), said steering assembly (4) being controlled by said control unit based on said data transmitted by said radar sensor means (10).

11. An apparatus of any one of the preceding claims, wherein said radar sensor means (10) comprises a continuous wave radar sensor of the FMCW (Frequency Modulated Continuous Wave) type and/or a pulse radar sensor and/or a doppler radar sensor.

12. An apparatus of any one of the preceding claims, wherein said radar sensor means (10) is of the 60 GHz pulse type.

13. A method for automatically wrapping a load with a film of stretch material comprising the steps of a. arranging, in a work environment in which there is at least one load to be wrapped, an apparatus for automatically wrapping said load with a film of stretch material equipped with radar sensor means (10); b. starting to wrap said film of stretch material around said load, and, at the same time, c. detecting instant by instant data relating to the distance from at least one obstacle comprising said load to be wrapped, through said radar sensor means (10); d. transmitting said data to a control unit; e. controlling, instant by instant, the direction of movement of said apparatus around said load to be wrapped, by means of said control unit; f. repeating said steps c-e until a wrapping cycle is completed.