VEHICLE FOR A CONVEYOR SYSTEM AND METHOD FOR THE SIMULTANEOUS TRANSPORT OF WORKPIECES AND WORKERS

Description

BACKGROUND OF THE INVENTION 1. Field of the invention

[0001] The invention relates to a vehicle for a conveyor system for the simultaneous transport of workpieces and workers. Such vehicle systems or conveyor systems are used in particular in the final assembly of motor vehicles, large household appliances, or machines that are manufactured in large quantities. 2. Description of the state of the art

[0002] In the final assembly of workpieces, conveyor systems are frequently used that allow workers to be transported along with the workpieces for extended periods. This enables workers to perform tasks on workpieces without having to walk alongside them.

[0003] The vehicles in these known conveyor systems have a workpiece holder for securing the workpiece, an assembly platform accessible to workers, and typically their own drive system designed to propel the vehicle independently of other vehicles in the conveyor system. Such vehicles also often feature a non-contact path sensor for determining the vehicle's position and a control unit for activating the drive system, among other things, based on a signal from the path sensor. During certain manufacturing steps, it is advantageous for such vehicles to form a convoy or group while transporting workers along with the workpieces. For example, a conveyor system of this type is described in DE 11 2017 113 931 A1. Sensors are arranged on the front and side surfaces of the assembly platform for orientation and / or collision avoidance.The sensors, for example, are designed as laser scanners and serve to monitor an area around the vehicles – the safety distance. This safety distance is chosen so that a vehicle can be brought to a stop with sufficient clearance before a potentially suddenly appearing obstacle. The top of the assembly platform is covered with a touch-sensitive floor covering that detects whether workers are present on the platform.

[0004] Forming a convoy or group of vehicles has proven problematic, as it requires maintaining the safety distance specified by the laser scanner for obstacle detection. The same applies when a vehicle approaches stationary structures, for example. Currently, this is only possible in specially secured areas, since the vehicle cannot then independently determine whether a collision is imminent or whether the reduced safety distance is intentional. SUMMARY OF THE INVENTION

[0005] It is an object of the invention to provide a vehicle and a method for the simultaneous transport of workpieces and workers, in which the aforementioned disadvantages are at least partially avoided and in which, in particular, a vehicle convoy can be easily formed, preferably without stationary safety devices.

[0006] This task is solved by a vehicle and a conveyor system for the simultaneous transport of workpieces and workers, the vehicle having a workpiece holder, an assembly platform accessible to workers, its own drive which is designed to drive the vehicle independently of other vehicles of the conveyor system, a non-contact path sensor for finding the path of the vehicle and a control unit for controlling the drive depending, among other things, on a signal from the path sensor.

[0007] According to the invention, the vehicle has a non-contact platform sensor for monitoring the assembly platform, wherein the platform sensor is configured to at least temporarily alternatively take over the monitoring of the vehicle's driving situation or at least temporarily additionally support the monitoring of the vehicle's driving situation.

[0008] According to the invention, it is therefore possible, for example, when the vehicle approaches a second vehicle or another dynamic or stationary disturbance contour, to monitor the vehicle's driving situation up to a certain minimum safety distance using the non-contact path sensor and, as soon as this safety distance is breached, to additionally or alternatively monitor the driving situation using the non-contact platform sensor. While the non-contact platform sensor actually serves to monitor the assembly platform and detect the presence of workers in the area it monitors, according to the invention it is designed to also monitor the driving situation of the entire vehicle.This is necessary, for example, when the vehicle has to approach another vehicle or any other obstacle closer than the intended safety distance. If this safety distance is breached, it is no longer guaranteed that the vehicle can stop at the given speed and thus avoid a collision in every case. To still ensure protection against a collision, and especially the safety of people, for the remaining distance between the vehicle and the other vehicle or obstacle, the platform sensor monitors the driving situation. The same applies when a vehicle group breaks up or when moving away from an obstacle. This can be relevant, for example, if two vehicles are traveling at a higher speed and a person enters the increasing gap between them.In this case too, it may be advisable to monitor the driving situation and, if necessary, trigger braking or a warning signal.

[0009] In a preferred embodiment, the non-contact platform sensor takes over monitoring of the driving situation or assists in monitoring the driving situation when the safety distance is breached. This takeover or assistance can occur at an appropriate time interval before the anticipated breach of the safety distance, so that (additional) monitoring of the driving situation by the platform sensor is already available when the safety distance is breached.

[0010] As previously explained, monitoring the driving situation can include collision avoidance, particularly for the protection of people. Other aspects relevant to the driving situation can also be handled or supported by the platform sensor. For example, it is conceivable that when the vehicle approaches another vehicle or another obstruction, certain areas may be more difficult for the path sensor to detect, or that the accuracy of the path sensor could be improved by the platform sensor. However, it is particularly advantageous to transfer the responsibility for personal protection to the platform sensor or to have it perform this function in addition to the other functions. In this context, personal protection is understood as controlling the vehicle's driving situation in such a way that any danger to workers or other persons in the vicinity of the vehicle can be ruled out.The procedures to be carried out as part of personal protection may include, for example, controlling the speed or direction of the vehicle, issuing acoustic, optical or electrical signals, or other safety measures.

[0011] In a further development of the invention, the platform sensor can be configured to dynamically or in stages adjust its range. For example, the platform sensor can normally monitor the walking area on the mounting platform for which it is designed. When approaching another vehicle or another static or dynamic obstruction that is intended to penetrate the safety distance provided for the path sensor, the platform sensor can generally or specifically increase its range in the area of ​​the expected approach. Once the vehicle is docked to the other vehicle or obstruction—i.e., the minimum desired distance (which can also be 0) has been reached—the platform sensor can adjust its range so that at least half of the remaining minimum distance is covered.It may also be arranged that one platform sensor of one vehicle covers the remaining distance on its own, while the corresponding platform sensor of the other vehicle reduces its range to prevent double coverage. Double coverage may also be desired in certain circumstances.

[0012] The described dynamic adjustment of the platform sensor can also be performed for the travel path sensor.

[0013] Previously, it was necessary to actively mask out obstructions—that is, areas defined by the safety distance—when a vehicle passed by, using software, for example, based on location. Unforeseen, dynamic obstructions triggered an emergency stop. This emergency stop situation had to be resolved manually, for example, by removing the obstruction or repositioning the vehicle. The muting of the obstruction had to be implemented in such a way as to reliably prevent the "accidental" masking of people.

[0014] Instead, it is now proposed to gradually increase or decrease the protective field of the driving path sensor depending on the actual speed of the vehicle and the associated stopping distance.

[0015] Warning fields can be positioned upstream of protective zones. If a warning field detects a disturbance contour, it initiates a reduction of the vehicle speed to the next lower level. The warning field is sized so that the lower speed is reached before the current protective zone is violated and would trigger an emergency stop.

[0016] This causes the vehicle to gradually decelerate as it approaches a disturbance contour until it reaches the lowest speed with the smallest protective field, without triggering an emergency stop condition and stopping at the disturbance contour. The personnel protection function of the path sensor remains active throughout this process. If the speed is not reduced as intended, the corresponding protective field initiates an emergency stop.

[0017] When approaching a bottleneck (especially when cornering, if the protective field extends beyond the curve), the vehicle will automatically reduce its speed, drive past the obstruction with the reduced protective and warning fields, and then, once the warning fields are clear, accelerate back to its original target speed. This method eliminates the need for any further intervention or muting (event- or location-dependent suppression of obstructions). Getting stuck on obstructions that do not extend into the driving path is impossible. The method works anytime, anywhere, and is not limited to specific locations or situations.

[0018] Preferably, the displacement sensor and the platform sensor operate horizontally. This means that, particularly when the displacement sensor and / or the platform sensor are configured as scanners, the orientation of the scanned area is essentially horizontal. Especially with the displacement sensor, it must be ensured that, for example, an unconscious person lying on the ground can be detected by it.

[0019] Preferably, the detection range of the platform sensor can be configured to extend beyond the mounting platform by a safety distance. Preferably, the safety distance by which the detection range of the platform sensor extends beyond the mounting platform correlates with the minimum safety distance of the travel path sensor; that is, it coincides with or is slightly larger than it. In this way, the safety function can be transferred from the chassis sensor to the platform sensor and vice versa without creating a gap in the protected area.

[0020] Preferably, the path sensor is designed to detect a horizontal cylindrical object with a diameter of 200 mm or larger. For this purpose, the path sensor can, for example, be designed as a linear scanner that covers the width of the vehicle or slightly beyond, essentially the horizontal area in front of the vehicle. The path sensor can operate at a height of, for example, 150 mm. Alternatively, the path sensor can be tilted downwards. This reduces the maximum range of the path sensor and makes it more difficult to evaluate the sensor signal for detecting potential obstacles, but may offer improved accuracy at close range.

[0021] Preferably, the platform sensor covers an area above the travel path sensor. "Above" can mean that the plane in which the travel path sensor operates is below the plane in which the platform sensor operates. The vertical distance between the detection plane of the platform sensor and the detection plane of the travel path sensor can, for example, be between 50 mm and 250 mm, preferably between 110 mm and 200 mm, and most preferably 150 mm. {Cylindrical body 200 mm high, travel path sensor located at a height of 150 mm, mounting platform level must not exceed 250 mm. Platform sensor is mounted 50 mm higher => distance between travel path sensor and platform sensor is 150 mm}

[0022] The task can also be solved by a conveyor system with at least two vehicles, as in one of the previous examples.

[0023] Furthermore, the task is also solved by a method for controlling such a vehicle, which comprises the following steps: monitoring the vehicle's driving situation with the path sensor; approaching a second vehicle to form a group, moving away from or increasing the distance to a second vehicle to break away from a group or approaching a stationary or moving disturbance contour; as soon as the safety distance to the second vehicle or the disturbance contour is breached, or as long as the second vehicle or the disturbance contour is within the safety distance, alternatively or additionally monitoring the driving situation with the platform sensor.

[0024] In this way, the advantages of the invention are also realized within the framework of a process.

[0025] An advantage of the procedure is that monitoring the driving situation includes collision avoidance, particularly for the protection of persons.

[0026] It may be advantageous to provide that the platform sensor dynamically or in stages adjusts its range during an approach to another vehicle or a disturbance contour, or during a move away from a second vehicle or a disturbance contour.

[0027] In a particularly advantageous embodiment, it is provided that in a group consisting of, for example, two vehicles, the driving path sensor of one vehicle takes over the distance control to a second vehicle.

[0028] It is particularly advantageous if the platform sensor monitors the assembly platform as well as a docking area for a second vehicle.

[0029] It is advantageous if the area detected by the driving path sensor and / or the platform sensor depends in its design on the current driving speed, the position, the load state of a vehicle and / or the distance to another vehicle.

[0030] The present invention enables the realization of a driverless transport system in which individual vehicles can approach other vehicles or suitable stationary structures until they make contact. The safety system operates without fixed protective devices and can be implemented particularly effectively between moving objects, such as when several vehicles dock to form a convoy. The safety system for each individual vehicle functions autonomously, eliminating the need for otherwise necessary secure communication with stationary structures or other vehicles. Regardless of location or system layout, the system reliably detects when people are on a vehicle and prevents hazardous movements. This is achieved by using a first scanner to ensure that no person or object is in the danger zone until a safety distance is breached.If the safety distance is breached, the first scanner is deactivated and a second scanner monitors the surroundings to ensure that no person enters the danger zone.

[0031] The electrical or control-related coupling of individual vehicles into a group can be realized as follows: A first vehicle travels in a group at the speed of the pack or group.

[0032] Each following vehicle automatically maintains its distance from the vehicle immediately in front. Communication between the vehicles or with a central control system is not necessary for this. However, communication can occur to initiate actions such as anticipatory or coordinated stopping maneuvers.

[0033] A specific gap dimension can be defined between the vehicles. Any change in this gap dimension is measured and recorded as a control deviation. The distance measurement can be performed with a primary scanner, such as a path scanner. For safety reasons, the gap is mechanically closed with a flexible cover. The maximum control deviation is limited both upwards and downwards.

[0034] The control system superimposes the speed of the group of vehicles. If the distance between them is too great, a catch-up speed is added, and if the distance is too small, a deceleration speed is subtracted. To prevent the control system from oscillating in a convoy of many vehicles, the control range is narrowly limited, and the controller can be implemented, for example, as a three-position step controller or a proportional (P) controller.

[0035] If the minimum gap is breached, for example in a traffic jam, the vehicle automatically brakes to a standstill. As soon as any vehicle in the convoy comes to a stop due to such an emergency stop, operational stop, or malfunction, the following vehicles catch up and also stop automatically. The vehicles ahead continue driving normally.

[0036] If the maximum gap to the vehicle in front is exceeded (break-off), the distance control is deactivated. The vehicle then travels at the speed of the group and assumes the role of the lead vehicle in the convoy. The gap to the vehicle in front is monitored by a second scanner, such as the platform scanner. The gap closes automatically when the vehicles in front stop for operational reasons. If the maximum gap is no longer exceeded, the distance control is automatically reactivated and the convoy is re-established.

[0037] Separation: If the first vehicle in the convoy quickly withdraws, the second vehicle cannot follow, even at a catching-up speed. The gap becomes too large, and the second vehicle automatically takes over leading the convoy at the group's speed.

[0038] Docking: A new vehicle approaches the last vehicle in the convoy from behind at docking speed. Once the maximum gap is reached, the spacing rules take effect and the convoy is formed. If the vehicle cannot close enough to the vehicle in front within a defined docking distance, it continues independently as the first vehicle of a new convoy at the convoy speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. These show: Figure 1 is a schematic top view of a conveyor system according to the invention, in which several vehicles approach different processing stations or areas in a group; Figure 2 is a perspective view of the group of vehicles. Figure 1Figure 3 is a perspective view of a vehicle according to the invention; Figure 4 is a schematic top view of the vehicle. Figure 3 , where the ranges of the path scanners and the platform scanners are indicated; Figure 5 a schematic top view of the vehicle of the Figures 3 and 4 , in which warning zones are provided in addition to protective zones; Figures 6-8 schematic views of different types of processing stations; Figures 9-11 schematic side views of different driving situations in platoon operation; Figure 12 schematic side view of different positioning of a car body on vehicles; Figures 13-15 schematic side views of different embodiments for covering a gap between two vehicles; and Figures 17-20 schematic top views of different movement patterns of vehicles in platoon operation. DESCRIPTION OF PREFERRED EXAMPLES

[0040] Figure 1A schematic top view illustrates a conveyor system 10 according to the invention, in which several vehicles 100 travel along a route 12 of a production line in platoon operation. The vehicles 100 form a platoon or convoy 102 when several successive processing stations or areas 14 are spatially closely adjacent to one another, or when a larger processing station extending over several vehicle lengths is approached. At the processing stations 14, workers 16 are working alongside or on top of the vehicles 100. The processing stations or areas 14 of the Figure 1 form an assembly line 18. At the processing stations 14, work materials or tools 20 are shown schematically.

[0041] Before entering assembly line 18, which is traversed in a group, there is a merging area 22 where a single vehicle 100 is incorporated into the group. Similarly, at the end of assembly line 18, an unmerging area 24 is provided where the group is dispersed.

[0042] Figure 2 Figure 1 shows a schematic perspective view of the convoy 102, in which several vehicles 100 are essentially linked together without any gaps. The convoy 102 moves, in a sense, like a single vehicle 100. Workers 16 can safely move back and forth between the vehicles 100 if desired.

[0043] Workpieces 106, for example vehicle bodies 108, are arranged on the vehicles 100 by means of workpiece holders 104. The workpiece holders can be, for example, pins or slides suitable for a vehicle body 108.

[0044] Figure 3 Figure 100, a perspective view illustrating a vehicle 100 that is part of the conveyor system 10, is shown. As mentioned previously, the vehicle 100 has a workpiece holder 104 to which a workpiece 106, in this case an unassembled vehicle body 108, is attached. The vehicle 100 also has an assembly platform 110, which is accessible to personnel such as workers 16. The vehicle 100 has a drive system (not shown) that enables omnidirectional movement. The vehicle 100 can therefore move in any direction in the plane. In particular, longitudinal and lateral movements with respect to the longitudinal axis of the vehicle 100 are possible.

[0045] Regarding a specific design of such a drive, reference is made to DE 10 2017 103 931 A1, in which an exemplary drive-rotation module is designed.

[0046] Integrated into the assembly platform 110 is a control unit 112, which, among other things, controls the drive of the vehicle 100.

[0047] The control unit 112 can, for example, include a navigation system that allows the vehicle 100 to orient itself in a production hall.

[0048] The vehicle 100 also has a travel path sensor 114, which in this case is designed as a travel path scanner 116. The travel path scanner 116 serves to monitor the driving situation of the vehicle 100 as described below with reference to the Figure 4 This will be explained in more detail. The path scanner 116 is designed to detect the area 118 in front of the vehicle 100 while it is traveling in the direction of travel and to warn of a possible collision. A safety zone 120 is provided, which must not be breached. The path scanner 116 is as described in Figure 3The path scanner is arranged to detect both the area 118 directly in front of the vehicle 100, which lies in the direction of travel of the vehicle 100. The path scanner can operate, for example, optically – as a laser scanner or as a camera – or acoustically – as an ultrasonic sensor. The path scanner 116 can also detect areas that extend laterally beyond the actual path area of ​​the vehicle 100.

[0049] This is in Figure 4 clearly illustrated. Figure 4 Figure 1 shows a schematic top view of the vehicle 100 without the workpiece 106 attached, so that the workpiece holder 104 is clearly visible in its outline. Two path scanners 116, 117 are arranged on the outer sides of the assembly platform 110. The path scanners 116, 117 are used in the Figure 4In the depicted driving situation, where vehicle 100 moves along its longitudinal axis X, the scanners are configured to detect areas 118 and 119 located in front of and behind vehicle 100, respectively, in the direction of movement X. Due to the arrangement of the path scanners 116 and 117, they are also capable of covering areas laterally adjacent to the direction of movement X, thus enabling collision avoidance even when the vehicle moves laterally Y. As can be seen in Figure 4, areas 118 and 119 protrude laterally beyond the actual vehicle contour.

[0050] In addition to the areas 118 and 119 designed as protective fields, warning fields may be provided that are located in front of the protective fields.

[0051] This is exemplified in Figure 5The same reference symbols are used as in Figure 4 for identical or comparable features. Vehicle 100 has, in addition to areas 118 and 119, the following: Figure 5 For clarity, only one area 118 is activated as a protective field, for example, for forward travel in direction X – a corresponding warning field 131 is displayed. Warning field 131 is positioned upstream of area 118 and can be used to adjust the speed and extent of both protective field 118 and warning field 131, as described above. Furthermore, additional areas or fields are positioned upstream of the additional areas 130 and 130', which are monitored by platform scanners 128 and 129. These additional areas or fields are also monitored and defined by platform scanner 128. Identical fields could be mirrored and monitored on the side of the other platform scanner 128.

[0052] Directly in front of the direction of travel X are two fields 133, 134, one after the other. Fields 135, 135 are located laterally in front of fields 133, 134. Further in the direction of travel X, fields 118, 131, which open at an angle of 10°, adjoin field 134.

[0053] While warning field 131 is permanently configured as warning field 131, the other fields 118, 133-136 can be used phased in as a protective field or as a warning field.

[0054] The adjustment of the vehicle's speed (100) and the modification of individual fields as warning or protection fields can be carried out according to the following scheme, for example: Driving speed: 60m / min 30m / min 15m / min 6m / min Definition "s" Emergency stop Emergency stop Emergency stop Emergency stop Definition "w" Warning field >30m / min Warning field > 15m / min Warning field >6m / min Forward direction of travel 0° to 5°: Field assignment s: 130, 130', 133, 134, 118 s: 130, 130', 133, 134 s: 130, 130', 133 s: 130, 130' w: 131 w: 118 w: 134 Forward direction of travel. 5° to 30° Field assignment n / a s: 130, 130', 133, 134, 135 / 136 s: 130, 130', 133 s: 130, 130' w: 134, 135 / 136 w: 118

[0055] The table above shows how the various fields can be successively redefined and, if necessary, even deactivated.

[0056] As in the Figure 3 As shown, the assembly platform 10 has a walkway area 122. This area represents the zone within which workers 16 can move safely on the platform and thus constitutes a safe zone. The walkway area 122 is separated from a restricted area 124. Workers 16 should be allowed access to the restricted area 124. To monitor the assembly platform 110, and in particular the walkway area 122 and the restricted area 124, non-contact platform sensors 126 in the form of platform scanners 128, 129 are provided.

[0057] As from the Figure 4As can be seen in the exemplary embodiment shown there, two platform scanners 128, 129 cover the entire area of ​​the assembly platform 110 not occupied by the workpiece holder 104. Additionally, it can be provided that the area covered by the platform scanners 128, 129 extends beyond the actual area of ​​the platform 110 and thus covers an additional area 130. Preferably, this additional area 130 overlaps at least partially with the safety area 120 of the path scanners 116, 117 with respect to its extent along the assembly platform 110, and particularly preferably extends beyond it. This is exemplified in Figure 4 shown. There, the additional area 130 of the platform scanner 129 overlaps the safety area 120 of the path scanner 116.

[0058] The platform scanners or path scanners 128, 129 are mounted on the mounting platform 110 and record in the Figures 3 and 4In the illustrated embodiment, the area on or slightly above the mounting platform 110 is monitored, but not areas below a plane formed by the top surface of the mounting platform 110. This is due, on the one hand, to the fact that the platform scanners 129, 128 are mounted inside the restricted area 124 of the mounting platform 110 and are thus set back from the edge of the mounting platform 110. Alternatively or additionally, one or more platform scanners could be mounted at the edge of the mounting platform 110, for example at the corners, like the path scanners 116, 117, thus enabling the monitoring of areas around the mounting platform 110 that are located below the top surface of the mounting platform 110.

[0059] During the Figures 3 and 4In the illustrated embodiment, the path scanners 116, 117 and the platform scanners 128, 129 provide corresponding signals or information to the control unit 112, thus enabling largely autonomous, or at least driverless, driving of the vehicle 100. The vehicle 100 can therefore avoid collisions via the path scanners 116, 117 and simultaneously monitor the assembly platform 110 via the platform scanners 128, 129 during both driving and stationary operation.

[0060] The Figures 6-8 The images show different operational situations of a vehicle 100. In the case of the Figure 6 In the situation shown, the assembly platform 110 of the vehicle 100 serves to provide a movable work platform for workers 16 who have to perform work on a vehicle body 108. For example, it may be provided that the workers, together with the assembly platform 110, move to the area shown in Figure 6The vehicle 100 moves to the symbolically represented processing station 14, performs manual tasks there during a stop, and then continues its journey on the assembly platform 110. Alternatively or additionally, it can be provided that the workers 16 only enter the assembly platform 110 after the vehicle 100 has reached processing station 14, perform manual tasks, and then leave the assembly platform again. In this case, the vehicle scanners 116 and 117, for example, can be responsible for ensuring a collision-free journey when approaching and leaving processing station 14. The platform scanners 128 and 129, on the other hand, can ensure, for example, that potentially restricted areas of platform 110 are not entered or that the correct workers 16—i.e., those with the appropriate qualifications—or the correct number of workers 16 are present on platform 110.

[0061] Figure 7 illustrates a different situation. In the Figure 7 At the depicted processing station 14', no workers are working on the vehicle body 108, but rather automated robots 26, 27, performing assembly tasks as examples. For instance, the robot 27 shown on the left attaches vehicle doors 28. At this processing station 14', the vehicle scanners 116, 117 and the platform scanners 128, 129 must ensure that no worker approaches, enters, or is on the assembly platform 110 during approach, since the operating area of ​​the robots 26, 27 is located in otherwise freely accessible areas of the assembly platform 110, and parts of the robots, for example, of robot 26, even extend far beyond the assembly platform 110.

[0062] Figure 8This illustrates another application scenario. A vehicle 100 transports a workpiece in the form of a vehicle body 108 on an assembly platform 110. A worker 16 can access the assembly platform 110 and then, for example, perform tasks on the vehicle body 108. Additional vehicles 100' and 100" are arranged alongside the vehicle 100. For example, the second vehicle 100' located on one side of the vehicle 100 can transport a worker 16' or serve as a walkable side platform. A third vehicle 100" can also be arranged alongside the vehicle 100 and be used for transporting materials or tools. Due to the uniform level of the assembly platforms provided by the respective vehicles 100, 100', and 100", the workers 16 and 16' can move freely when the vehicles are stationary or during platoon transport.

[0063] Simultaneously, the path scanners 116, 117 and the platform scanners 128, 129 can be used to enable the approach and departure of the vehicles 100, 100', 100" to each other and to signal that safe access is possible when the vehicles are relatively stationary relative to each other. This can be indicated, for example, by visual or acoustic signals for the workers 16, 16'. Alternatively or additionally, it is also possible that barriers are provided on the assembly platforms 110, which are released when safe access is possible.

[0064] The Figures 9-11 They show various driving situations with at least two vehicles. Figure 9At least two vehicles 100, 100' form a convoy or group 102 and move at a common speed. A third vehicle 200 maintains the same speed and thus keeps contact with the convoy 102, becoming part of it. The workers on the assembly platforms 110, 110', 210 can, in principle, move freely on the assembly platforms within the designated walking areas. Each of the vehicles 100, 100', 200 has a path scanner 116, 116', 216, which is located in the Figure 9The current driving situation is used to maintain the distance between one vehicle and the vehicle in front within certain limits. This ensures, for example, that the distance 232 between two assembly platforms 110 and 210 never exceeds a specific maximum safety distance of, for example, 20 or 50 mm. At the same time, this safety distance 232 can be used to compensate for minor speed differences or, in the case of necessary directional adjustments, to facilitate or even enable driving maneuvers by adjusting the actual distance.

[0065] Figure 10 This illustrates the approach process of a vehicle 200 – in the illustrated embodiment loaded with a vehicle body 208 as a workpiece – to a group 102, formed of two vehicles 100 and 100'. In the Figure 10In the depicted driving situation, the group 102 is moving at a certain speed, while the approaching vehicle 200 is traveling at a higher speed. Alternatively, the group 102 could be stationary, and the vehicle 200 could be approaching it. As long as the distance between the approaching vehicle 200 and the rearmost vehicle 100 in the group 102 is sufficiently large, as shown in Figure 10 As shown, the travel path sensor 216 is used to control this distance and thus also the relative speed. Simultaneously, the travel path sensor, in the form of the vehicle scanner 216, is used to monitor the gap 132 between the vehicles for potential collisions. The gap 132 represents a particular hazard for operators such as the workers 16 and must be continuously monitored, especially during approach maneuvers.

[0066] Figure 11Figure 1 shows the situation in which vehicle 200, approaching group 102, is within the safety distance defined by the path scanner 216. Its collision monitoring is inactive in this driving situation. In this driving situation, the platform scanner 229 of the approaching vehicle 200 takes over the task of collision monitoring of the gap 232. If the gap 232 cannot be covered by other mechanical devices, the platform scanner 229 can continuously monitor the gap 232. Otherwise, it monitors the gap 232 until it is covered. This monitoring can always take place if a gap 132 arises during a maneuver—that is, during a change in the driving situation—which poses a potential hazard to the operating personnel, for example, the workers 16.

[0067] Figure 12This illustrates the possibility of dynamically adjusting the range of the platform scanner 128. While in the Figure 12 In the left-hand situation shown, the vehicle 100 has its body 108 on an elevated workpiece holder 104; the vehicle body 108' is on the in Figure 12 The right-hand vehicle 100 is mounted lower. The workpiece holder 104, for example, can have a lifting device and, if necessary, a rotating device. Depending on the requirements, the platform scanner 128 of the left-hand vehicle 100 can be adjusted so that the worker 16 can also work below the vehicle body 108, thus increasing the walking area 122. Conversely, at higher speeds and with possible pitching or tilting movements of the vehicle 104, it may be necessary to reduce the walking area 122 to such an extent that there is no danger to the worker 16 during such movements.

[0068] The Figures 13-15 Illustrating various embodiments for the mechanical covering of the gap or the distance 132. Figures 13-15 The upper illustration shows an assembly platform 210 approaching an assembly platform 110 of a preceding vehicle. In the upper illustration, the approach process is underway; in the lower illustration, it is complete. Figure 13 Figure 1 shows elastic elements 140, 240 attached to the front face of the mounting platform 110, 210. Once the approach process is complete, the gap 102 is minimized, the elastic elements are in contact and, depending on the design, may be slightly compressed. Electrical contacts can also be made via the contact of the elastic elements 140, 240, which then transmit a corresponding signal to the control unit 112.

[0069] In the depictions of the Figure 14The closure or cover elements are designed as sliding elements 142, for example sliding plates. Figure 15 The figure shows hinged elements, for example, hinged panels, which serve as covers. Both the sliding elements 142, 242 and the hinged elements 144, 244 are mounted on the front face in the illustrated embodiment and can also serve as elements that can trigger an electrical signal upon contact. All the shown locking elements can be designed so that access for a worker 16 is unproblematic, thus creating a common walkway that extends across assembly platforms or vehicles.

[0070] The Figures 16-20 show different movement possibilities of a vehicle 100 when approaching a vehicle convoy or when separating from a vehicle convoy.

[0071] Figure 16Figure 1 shows, in three representations A, B, and C in this order, the separation of a vehicle 101 from a vehicle group 103 and its connection to a vehicle group 102, consisting of two vehicles 100 and 100'. To separate vehicle 101 from vehicle group 103, it is accelerated along direction Y to create a distance 232 between vehicle 101 and the remaining vehicle group 103. To then connect vehicle 101 to vehicle group 102, it is decelerated in direction Y until it comes to a complete stop in that direction, and then accelerated in direction X, corresponding to the direction of movement of vehicle group 102. This acceleration is shown in Figure B.Upon reaching the vehicle convoy 102, further acceleration, namely deceleration to convoy speed, is necessary. Figure C shows the newly formed vehicle convoy 102, consisting of vehicles 101, 100, and 100', moving at a common speed along direction X. Simultaneously, vehicle convoy 103 is shown, continuing at undiminished speed in direction Y. As can be seen from this illustration, moving the vehicles 101 along only two axes perpendicular to each other is complex in terms of control and the required movement sequences. Several accelerations in different directions are necessary.

[0072] The illustrations of Figure 17Figures A, B, and C again illustrate a movement sequence that, starting from the same initial position, reaches the same final state. Here, however, the fact that vehicle 101 is equipped with an omnidirectional chassis is utilized. This allows vehicle 101 to accelerate and move along a direction of movement 150. This direction of movement 150 immediately creates a distance 232, which is required between vehicle 101 and the remaining vehicle convoy 103. Simultaneously, the direction of movement 150 immediately reduces the distance 132 between vehicle 101 and the target vehicle convoy 102. Thus, with a single acceleration to reach the target vehicle convoy 102 (and a subsequent deceleration to convoy speed), the transition from one vehicle convoy 103 to the second vehicle convoy 102 can be achieved.

[0073] In the illustrations of Figure 18 is in the same way as in the previous embodiments of the Figure 16 and 17 Figures A, B, and C show a transition situation from one vehicle convoy 103 to a second vehicle convoy 102. In contrast to the Figure 17 A non-linear route 152 is planned for the transferring vehicle 101. Rather, route 152 is a curve that initially allows for a rapid enlargement of the gap 232 between the remaining vehicle train 103 and the vehicle 101 to be transferred. After a short time along route 152, the gap 132 between the destination vehicle train 102 and the vehicle 101 to be transferred is closed. The precise parallel alignment of vehicle 101 with the connecting vehicle train 102 can also occur later along route 152, even after the gap 132 has been closed (as shown in Figure C).

[0074] Figure 19 also shows in three illustrations one to Figure 18 a very comparable transfer process from one group 103 to a second group 102 of a vehicle 101. The path described by the center of gravity of vehicle 101 is very similar to the path 152 of the Figure 18 In contrast, however, track 154 of the Figures 19 a simultaneous rotation of the vehicle 101 takes place. In the embodiment described above, the Figures 19 On track 154 shown, vehicle 101 rotates 90° from above and thus joins the alignment of vehicles 100, 100' of the group 102.

[0075] Figure 20 The figure clearly shows a group of vehicles 102, in which the individual vehicles 100 are laterally offset along a route 156.

Claims

1. A vehicle (100) for a conveyor system ( 10) for the simultaneous transport of workpieces (100) and workers (16), wherein the vehicle (100) has a) a workpiece holder (104), b) an assembly platform (100) accessible to workers (16), c) a dedicated drive which is set up to drive the vehicle (100) independently of other vehicles (100') of the conveyor system (10), d) a contactless route sensor (114) for monitoring the driving situation of the vehicle 100 within a safety distance (120) and e) a control device (112) for controlling the drive, inter alia depending on a signal from the route sensor (114), characterized in that f) the vehicle (100) has a contactless platform sensor (128, 129) for monitoring the assembly platform (110), wherein the platform sensor (128, 129) is set up to alternatively take over the monitoring of the driving situation of the vehicle (100) at least temporarily or additionally support the monitoring of the driving situation of the vehicle (100) at least temporarily.

2. The vehicle as claimed in claim 1, wherein the takeover or the support are carried out on falling below the safety distance (120).

3. The vehicle as claimed in any one of the preceding claims, wherein the monitoring of the driving situation includes collision avoidance, in particular for personal protection.

4. The vehicle as claimed in any one of the preceding claims, wherein the platform sensor (128, 129) is set up to adjust its range dynamically or in stages.

5. The vehicle as claimed in any one of the preceding claims, wherein the route sensor (118, 119) and the platform sensor (128, 129) work in the horizontal.

6. The vehicle as claimed in any one of the preceding claims, wherein the detection space of the platform sensor (128, 129) can be set up so that it extends beyond the assembly platform (110) by a safety distance (120).

7. The vehicle as claimed in any one of the preceding claims, wherein the platform sensor (128, 129) covers an area above the route sensor (118, 119).

8. A conveyor system (10) with at least two vehicles (100, 101) according to any one of the preceding claims.

9. A method for controlling a vehicle with a workpiece holder, an assembly platform accessible to workers, a dedicated drive set up to drive the vehicle independently of other vehicles of the conveyor system, a contactless route sensor for monitoring the driving situation of the vehicle within a safety distance, a control device for controlling the drive, inter alia depending on a signal from the route sensor, and a contactless platform sensor for monitoring the assembly platform, with the steps: monitoring the driving situation of the vehicle with the route sensor; approaching a second vehicle to form a group, moving away from a second vehicle for detachment from a group or an approach of the vehicle to a moving or stationary interfering contour; once the safety distance from the second vehicle or the interfering contour is fallen below or as long as the second vehicle or the fault contour is within the safety distance, alternatively or additionally carrying out monitoring of the driving situation with the platform sensor.

10. The method as claimed in claim 9, wherein the monitoring of the driving situation includes collision avoidance, in particular for personal protection.

11. The method as claimed in claim 9 or 10, wherein the platform sensor adjusts its range dynamically or in stages during an approach or while moving away.

12. The method as claimed in any one of claims 9 to 11, wherein in a group the route sensor takes over control of the distance from a second vehicle.

13. The method as claimed in any one of claims 9 10 12, wherein the platform sensor takes over the monitoring of the assembly platform and a docking area to the second vehicle.

14. The method as claimed in any one of claims 9 to 13, wherein the area detected by the route sensor or / and the platform sensor depends on the current driving speed, the position, the load state of one vehicle and / or the distance from another vehicle.