DE102019201130B4 - Method and mobile transport device for transporting at least one transport item - Google Patents

Abstract

A method for transporting at least one transport item (10), comprising the steps of: arranging the at least one transport item (10) on a transport platform (2) of a mobile transport device (1), detecting a position-resolved reference contact force (20) of the at least one on the transport platform (2) arranged transport goods (10) by means of at least two force sensors (3) in a rest state of the transport device (1), regulation of an inclination (23) of the transport platform (2) by means of an actuator (6), with a position-resolved actual position during transport Contact force (21) of the at least one transport item (10) arranged on the transport platform (2) is recorded by means of the at least two force sensors (3), and where at least one control criterion is a deviation between the position-resolved actual contact force (21) and the position-resolved reference Contact force (20) is minimized.

Description

The invention relates to a method and a mobile transport device for transporting at least one transport item.

Small vehicles, so-called micromobiles, are a promising way of fulfilling future transport tasks, especially in urban areas. In this case, it may be necessary that transported goods transported with the aid of such a mobile transport device experience the lowest possible transverse acceleration during transport.

From the DE 10 2016 222 800 A1 A compensation device and a method for vehicles for compensating for a travel movement of the vehicle are known, the compensation device having a detection unit for detecting at least the direction or the acceleration of the driving movement, an evaluation unit for evaluating the detected driving movement, and an adjustment unit for positioning a regulating unit relative to the evaluated one Has driving movement.

Compensating for a transverse acceleration of a goods transported by means of a mobile transport device is currently only solved in an unsatisfactory manner.

• - Anordnen des mindestens einen Transportgutes auf einer Transportplattform einer mobilen Transportvorrichtung,
• - Erfassen einer positionsaufgelösten Referenz-Aufstandskraft des mindestens einen auf der Transportplattform angeordneten Transportgutes mittels mindestens zwei Kraftsensoren in einem Ruhezustand der Transportvorrichtung, wobei während des Transportierens eine positionsaufgelöste Ist-Aufstandskraft des mindestens einen auf der Transportplattform angeordneten Transportgutes mittels der mindestens zwei Kraftsensoren erfasst wird.

The DE 10 2014 226 108 A1 discloses a method for transporting at least one cargo, comprising the steps:

• - Arranging the at least one transport item on a transport platform of a mobile transport device,
• - Detection of a position-resolved reference contact force of the at least one transported goods arranged on the transport platform by means of at least two force sensors in a rest state of the transport device, wherein a position-resolved actual contact force of the at least one transported goods arranged on the transport platform is recorded by means of the at least two force sensors during transport.

The DE 10 2007 017 691 A1 discloses a method of preventing a vehicle from tipping over when cornering. The lifting of a wheel or the beginning of lifting of a wheel is determined via displacement sensor, which corresponds to the detection of a position-resolved actual contact force. A force is applied to the wheel in question by means of an actuator, for example, when the rear wheel on the inside of the curve is lifted off, the actuator of the front wheel on the outside of the curve is adjusted in the Z direction so that the rear wheel lifted off is pushed back onto the road.

From the DE 10 2011 080 245 A1 A method for monitoring a load on a loading area of a vehicle is known, the method comprising the step of: determining load information about the loading on the loading area by means of at least one weight signal, the weight signal representing a signal from a weight sensor arranged on the loading area.

From the DE 10 2005 062 286 A1 a device for estimating the center of gravity in a vehicle is known, with a computing device that evaluates a pitching movement of the vehicle that occurs under the influence of longitudinal acceleration and / or a rolling movement of the vehicle that occurs under the influence of lateral acceleration to estimate the center of gravity.

The invention is based on the object of creating a method and a mobile transport device for transporting at least one transport item, in which a transverse acceleration of the transport item can be better compensated for.

According to the invention, the object is achieved by a method having the features of claim 1 and a mobile transport device having the features of claim 6. Advantageous embodiments of the invention emerge from the subclaims.

In particular, a method for transporting at least one transport item is provided, comprising the steps of: arranging the at least one transport item on a transport platform of a mobile transport device, detecting a position-resolved reference contact force of the at least one transport item arranged on the transport platform using at least two force sensors in a state of rest the transport device, regulation of an inclination of the transport platform by means of an actuator, whereby a position-resolved actual contact force of the at least one transport item arranged on the transport platform is recorded by means of the at least two force sensors during transport, and at least one control criterion is a deviation between the position-resolved actual Contact force and the position-resolved reference contact force is minimized.

Furthermore, a mobile transport device for transporting at least one transport item is created, comprising a transport platform, a transport means for moving the transport platform, at least two on the transport platform arranged force sensors for detecting a position-resolved contact force of at least one transported goods arranged on the transport platform, an actuator for setting an inclination of the transport platform, and a controller, the controller being designed to regulate the inclination of the transport platform by means of the actuator and at least one control criterion To minimize the discrepancy between a position-resolved actual contact force of the at least one transport item arranged on the transport platform during transport and a position-resolved reference contact force of the at least one transport item arranged on the transport platform, detected in a state of rest.

The advantage of the invention is that an arbitrarily designed transport item with respect to a mass distribution can be transported with a compensated transverse acceleration, i.e. a compensated acceleration acting transversely or parallel to a surface of the transport platform, since the proposed control mechanism allows a mass distribution of the at least one transport item considered. In particular, a change in the mass distribution during transport can thereby also be taken into account, which is caused, for example, by a shift in the center of gravity of an unstable transport good. For example, a torque occurring on the goods to be transported during acceleration while the mobile transport device is cornering and a resulting mass or weight shift on the transport platform can be taken into account. Such a weight shift has, for example, a greater effect in the case of an extended object with a center of gravity far away from the transport platform, such as a floor lamp or an uplight, than in the case of goods that are more compact in terms of expansion and weight distribution, such as a beverage can. By means of the method according to the invention and the mobile transport device according to the invention, this can be taken into account when regulating the inclination of the transport platform. Transport of goods to be transported can thereby be carried out in an improved, in particular safer manner.

In particular, the transport platform has a substantially flat surface on which the at least one transport item can be arranged and transported. In particular, it is provided here that the at least one transport item can be transported on the transport platform without any further fastening or fixing. However, it can also be provided that the transport platform has a surface adapted to a shape of the goods to be transported, for example if the goods to be transported cannot easily be arranged on a flat surface. It can also be provided that fastening means and / or braking or fixing devices are additionally formed on the transport platform, such as rails, clamps and / or rubber studs etc.

Goods to be transported are in particular goods to be transported, such as boxes, containers or cardboard boxes in which goods are packed. However, goods to be transported do not have to be packed, but can also be transported on the transport platform without packaging. Examples of unpacked goods to be transported are a beverage can, an uplight with a stand or a water box. However, a cargo can also be a person. The mobile transport device can therefore in principle also be used to transport one or more people.

A force sensor is designed in particular as a piezo force sensor or a resistive force sensor. Other force sensors can also be used, such as spring body force transducers, the deformation of which is detected by means of strain gauges or capacitive sensors. A sensitivity of the force sensors is in particular coordinated with the specific application scenario in each case, that is to say with the masses or the weight forces occurring in the goods to be transported. Contact forces detected by the force sensor are provided to the control as a contact force signal.

The mobile transport device is in particular able to drive automatically. For this purpose, the mobile transport device comprises, in particular, a sensor system, for example a camera, a radar sensor, a lidar sensor and / or an ultrasonic sensor, which detects the surroundings of the mobile transport device, and an evaluation device which evaluates sensor data recorded by the sensor system and, for example, sends it to a controller which controls the means of transport in order to transport goods arranged on the transport platform. To control the movement of the mobile transport device, it can also have at least one acceleration sensor and / or a navigation or position determination device.

The means of transport of the mobile transport device can for example comprise wheels. Alternatively or additionally, the means of transport can also comprise chains or legs with which locomotion is possible. For example, four contact points can be provided on the floor, with at least one wheel being arranged at each of the contact points.

The inclination refers in particular to the angle of inclination of a surface of the transport platform with respect to a horizon. If the surface of the transport platform is oriented horizontally, the inclination is therefore zero. Since the surface of the transport platform has two degrees of freedom of inclination in relation to the inclination (for example in an x-direction and a y-direction in Cartesian coordinates), the inclination is clearly defined by specifying two inclination angles.

The actuators include, in particular, actuators that can change the inclination of the transport platform. For this purpose, the actuators are in particular connected to the transport means in such a way that a distance between the transport platform and the transport means can be changed at different positions and, as a result, an inclination of the transport platform relative to a horizon can be changed. The actuators can work electrically, pneumatically and / or hydraulically. For example, if the transport platform has a square or rectangular shape, provision can be made for an actuator to be arranged at one of the corners so that the inclination can be changed in two degrees of inclination by controlling the four actuators.

Ideally, the actuator system is regulated in such a way that the deviation between the position-resolved actual contact force and the position-resolved reference contact force approaches zero. In particular, the control concept is repeatedly oriented at each point in time to the respective force sensor with the greatest deviation in terms of amount between the reference contact force and the actual contact force. This means that the transport platform is inclined or lowered or raised with the correct sign in the direction in which the greatest deviation from the reference contact force can be determined. When regulating, weightings or mean values of the individual force sensors can also be taken into account. It is also possible to mount another plate above the force sensors on the transport platform. A mechanical force distribution or averaging via the force sensors can hereby be achieved. Further control criteria can also be taken into account, such as a detected or estimated acceleration of the transport platform or an anticipated route of the mobile transport device, for example in order to set an inclination in advance, for example in order to tip a transport item over an inclination of the transport platform before executing a curve to compensate foresighted torque acting on a center of gravity of the transported goods.

In principle, several goods can also be transported. It can be provided here that the regulation of the inclination then takes place on the basis of mean values of the respective contact forces. Alternatively, regulation can also be carried out on the basis of the transported goods with the greatest vertical force or on the basis of the most unstable transported goods and / or a center of gravity of the transported goods.

The control can be designed as a combination of hardware and software, for example as program code that is executed on a microcontroller or microprocessor.

In one embodiment it is provided that the position-resolved reference contact force and the actual contact force are recorded by means of force sensors which are arranged in the form of a matrix at regular intervals on or on the transport platform. In this way, the reference contact force and the actual contact force can be determined for positions that are arranged at regular intervals from one another on the transport platform. For example, it can be provided to define an x-direction and a y-direction on the transport platform and to arrange the force sensors at regular intervals along these directions so that a matrix-shaped grid is created. The contact forces can then be represented as a function of these directions, i.e. in the example mentioned by specifying x and y coordinates. If the actuators can be controlled with reference to these directions, the regulation of the inclination can be carried out particularly easily.

In one embodiment of the mobile transport device, provision is accordingly made for the at least two force sensors to be arranged in the form of a matrix at regular intervals on or on the transport platform.

In a further embodiment it is provided that after the at least one transport item has been arranged on the transport platform, a reference run is carried out, an acceleration being estimated and / or detected by means of at least one acceleration sensor during the reference run, and during the reference run using the at least two force sensors a position-resolved reference contact force is detected, and a center of gravity of the at least one transported good is estimated from the estimated and / or detected acceleration and the position-resolved reference contact force, and the inclination of the transport platform is additionally or alternatively regulated on the basis of the estimated center of gravity . A center of gravity of a cargo can be estimated by means of the reference travel carried out. During the reference run, a specified, i.e. known distance is traveled along which the At least one item to be transported experiences accelerations which are caused, for example, by starting, braking or cornering. The accelerations occurring here are detected by means of the at least one acceleration sensor, in particular in a time-resolved manner, or are estimated on the basis of the known trajectory of the distance. Simultaneously with the execution of the reference travel, a position-resolved contact force of the at least one transport item on the transport platform is recorded by means of the at least two force sensors. Depending on the position of the center of gravity of the at least one item to be transported relative to the transport platform, the center of gravity can experience a torque that leads to a weight shift on the transport platform. This weight shift is recorded by means of the force sensors. The greater such a shift turns out to be with the same acceleration, the greater the distance between the center of gravity and the surface of the transport platform. The greater the distance between the center of gravity and the surface of the transport platform, the more unstable the at least one transport item becomes when the mobile transport device is transported or accelerated and when cornering. This is taken into account when regulating the slope. For example, by regulating the inclination, it can be achieved that the center of gravity does not change its position relative to the transport platform or only changes it insignificantly when the mobile transport device is traveling. The dependency of a weight shift of the transported goods on a center of gravity can be determined or calculated, for example, by means of simulations for a large number of transported goods with different centers of gravity. However, it can additionally or alternatively be provided to determine the dependency experimentally, for example with the help of a large number of test bodies with different focus positions. The obtained results of the simulation (s) and / or the experiments can, for example, be stored in a memory device of the control and used by interpolation and / or extrapolation to estimate a center of gravity for a cargo.

If an estimated center of gravity and a weight or a mass of a transported good are known, it is possible in particular to calculate which forces or transverse accelerations would act on the center of gravity or the transported good during a given cornering (or braking or approach) in the event that the inclination of the transport platform is not changed. Furthermore, it can be calculated which inclination the transport platform would have to have so that the calculated transverse accelerations do not occur. An inclination calculated in this way could then be set directly on the transport platform. Alternatively, the inclination can be increased continuously while the current transverse acceleration is calculated. The inclination is then regulated in advance in such a way that the calculated transverse acceleration is minimized. This is advantageous because on the basis of a previously known route, for example cornering, the inclination can be controlled or regulated accordingly in advance. Lateral acceleration can be minimized or compensated for in an improved manner.

Provision can be made for parameters of a transport trip to be adapted on the basis of the determined center of gravity of the at least one transport item. For example, a journey can be carried out overall at a reduced speed or reduced acceleration (s) if the center of gravity of the at least one transport item is at a large distance from the surface of the transport platform.

In one embodiment of the mobile transport device it is accordingly provided that the controller is further designed to control the means of transport in such a way that a reference travel is carried out after the at least one transport item has been arranged on the transport platform, and an acceleration of the transport platform during the reference travel is estimated and To estimate a center of gravity of the at least one transported good from a position-resolved reference contact force recorded during the reference run and the estimated acceleration, and to regulate the inclination of the transport platform additionally or alternatively on the basis of the estimated center of gravity.

In a further-developing embodiment of the mobile transport device, it is further provided that the mobile transport device comprises at least one acceleration sensor for detecting an acceleration of the transport platform, the controller also being designed in such a way that the center of gravity of the at least one transported goods is additionally or alternatively based on a means of estimate the acceleration of the transport platform detected by the acceleration sensor.

In one embodiment it is provided that two parallel control structures are used to control the inclination, one of the control structures minimizing as a control criterion a deviation between the position-resolved actual contact force and the position-resolved reference contact force by changing the inclination in relation to one of two degrees of freedom of inclination , and wherein the other control structure is the deviation between the position-resolved actual contact force and the position-resolved reference contact force as a control criterion by changing the Inclination minimized with respect to another of the two degrees of freedom of inclination. In particular, it can be provided that the two degrees of freedom of inclination correspond to the directions of a matrix defined by an arrangement of the force sensors on the transport platform, so that the detected contact forces and the degrees of freedom of inclination have the same coordinate system as a reference system. If the degrees of freedom of inclination are designated with an x-direction and a y-direction, for example, then the control structures can be designed separately for the x-direction and the y-direction.

In one embodiment of the mobile transport device it is accordingly provided that the controller is further designed to use two parallel control structures to control the inclination, one of the control structures using a deviation between the position-resolved actual contact force and the position-resolved reference contact force as a control criterion Changing the inclination is minimized in relation to one of two degrees of inclination freedom, and the other control structure as a control criterion minimizes the deviation between the position-resolved actual contact force and the position-resolved reference contact force by changing the inclination in relation to another of the two degrees of inclination freedom.

In a further embodiment, it is provided that before the position-resolved reference contact force is detected, an inclination of the transport platform is detected by means of an inclination sensor and is corrected by means of the actuators. In this way, a surface of the transport platform can be brought into a horizontal plane, at least in the middle, so that the position-resolved reference contact force is not falsified by an already existing inclination. The inclination sensor can be designed, for example, in the form of at least one gyroscope with which an inclination of the transport platform can be determined. However, other types of inclination sensors can also be used, for example microelectromechanical systems or sensors that work with the aid of a liquid level.

In one embodiment of the mobile transport device, it is accordingly provided that the mobile transport device comprises an inclination sensor for detecting an inclination of the transport platform, the controller further being designed to control the actuators on the basis of a detected inclination of the transport platform prior to detecting the reference contact force, so that the recorded inclination of the transport platform is corrected.

• 1 eine schematische Darstellung einer Ausführungsform der mobilen T ransportvorri chtung;
• 2 ein schematisches Ablaufdiagramm einer Ausführungsform des Verfahrens zum Transportieren mindestens eines Transportgutes;
• 3 eine schematische Darstellung einer beispielhaften Ausführungsform einer Regelstruktur zum Regeln einer Neigung der Transportplattform.

The invention is explained in more detail below on the basis of preferred exemplary embodiments with reference to the figures. Here show:

• 1 a schematic representation of an embodiment of the mobile transport device;
• 2 a schematic flow diagram of an embodiment of the method for transporting at least one item to be transported;
• 3 a schematic representation of an exemplary embodiment of a control structure for regulating an inclination of the transport platform.

In 1 Figure 3 is a schematic representation of an embodiment of the mobile transport device 1 shown in a plan view, a side view and in the form of a signal flow diagram.

The mobile transport device 1 includes a transport platform 2 , on the force sensors 3 are arranged at regular intervals in the form of a two-dimensional matrix, a means of transport 4th which four wheels 5 includes (only two of them are visible in the illustration). The means of transport 4th furthermore includes associated drive devices (not shown), such as electric motors, and an energy store (not shown). The mobile transport device also includes an actuator 6th , which four electric linear motors 7th includes (only two of them are visible in the illustration), and a control 8th .

The mobile transport device 1 furthermore comprises a sensor system (not shown) for detecting the surroundings of the mobile transport device 1 and an evaluation device (not shown) for evaluating the environmental data captured by the sensor system. In particular, the means of transport 4th based on the evaluated environmental data, automated by the control 8th can be controlled so that it can automatically drive from a starting point to a destination and independently drive a route.

Becomes a cargo to be transported 10 on the transport platform 2 arranged, so detect the force sensors 3 on which the transported goods 10 rests, in each case a contact force acting there 20th , 21st . Before the cargo 10 from the mobile transport device 1 is transported to a destination, a position-resolved reference contact force is in a rest state 20th of the transported goods 10 by means of the force sensors 3 detected.

Then the transported goods 10 by controlling the means of transport 4th or the individual wheels 5 transported to the destination. During the Transporting becomes an actual contact force continuously, that is to say repeatedly at regular intervals or continuously 21st of the transported goods 10 by means of the force sensors 3 detected. The control 8th forms from the reference contact force 20th and the actual uprising force 21st a deviation or a difference. The controller regulates based on the deviation or the difference 8th distances 11 the transport platform 2 to the ground 12 at the respective corners, creating angles of inclination with respect to an axis of rotation 30th in the x-direction and a rotation axis 31 can be changed in the y-direction, so that an overall inclination of the transport platform 2 in two degrees of freedom of inclination 32 , 33 can be changed or regulated. The regulation takes place by regulating a deflection 15th of the actuators 6th or the linear motors 7th at the respective corners of the transport platform 2 . The deviation or the difference from the reference contact force is provided as a control criterion 20th and actual insurgency 21st to minimize.

By minimizing the deviation or the difference between the reference contact force 20th and actual insurgency 21st can do that on the transport platform 2 arranged transport goods 10 be transported without lateral acceleration, i.e. parallel to the surface there is an acceleration of the transport object 10 largely compensated. This allows the transported goods 10 even without an additional attachment to the transport platform 10 be transported safely. In particular, transported goods 10 can be transported improved with a location of the center of gravity that is unfavorable for transport. A complex and time-consuming fastening or locking etc. of the transported goods 10 can thus be omitted. This enables, in particular, rapid loading and unloading of the mobile transport device 1 with cargo 10 .

It can be provided that the controller 8th is also designed in such a way, the means of transport 4th to be controlled in such a way that after the at least one transport item has been arranged 10 on the transport platform 2 a reference run is carried out, and an acceleration of the transport platform 2 to estimate during the reference run and from a position-resolved reference contact force recorded during the reference run 20 ' and the estimated acceleration a center of gravity 13 of at least one transport good 10 to estimate. The control 8th regulates the inclination of the transport platform 2 then additionally or alternatively on the basis of the estimated focus 13 .

Furthermore, the mobile transport device 1 an accelerometer 9 for detecting an acceleration 22nd the transport platform 2 exhibit. The control 8th is then designed to focus 13 of at least one transport good 10 additionally or alternatively on the basis of a reference run by means of the acceleration sensor 9 detected acceleration 22nd the transport platform 2 to estimate.

It can also be provided that the mobile transport device 1 a tilt sensor 14th for detecting a slope 23 the transport platform 2 with respect to a horizon. The control 8th is then also designed in such a way before the reference contact force is detected 20th the actuators 6th or the linear motors 7th based on the recorded slope 23 the transport platform 2 to control so that the detected inclination 23 the transport platform 2 is corrected and the transport platform 2 is aligned horizontally at least on average in the rest state.

In 2 a schematic flow diagram of an embodiment of the method for transporting at least one item to be transported is shown.

After the start 100 the process is carried out in one process step 101 at least one transport item is arranged on a transport platform of a mobile transport device. In principle, more than one transport item can also be arranged on the transport platform.

Before the at least one transport item is transported, a method step 102 a position-resolved reference contact force of the at least one transport item arranged on the transport platform is detected by means of at least two force sensors when the transport device is in a state of rest.

It can be done in a preceding process step 200 It can be provided that before the position-resolved reference contact force is detected, an inclination of the transport platform is detected by means of an inclination sensor and corrected by means of the actuators, so that the transport platform is horizontally aligned at least on average and the reference contact force can be detected unaltered.

The at least one item to be transported is then carried out in one process step 103 transported. The procedural step 103 comprises the procedural steps 104-106 which are carried out during transportation.

The controller controls the transport in one process step 104 the means of transport so that the mobile transport device is moved from a starting point to a destination.

During the transport is in one process step 105 a position-resolved actual contact force of the at least one transported goods arranged on the transport platform is detected by means of the at least two force sensors. This is done repeatedly so that current values for the actual contact force can always be provided for regulating the inclination.

Furthermore, during the transport in one process step 106 an inclination of the transport platform is regulated by means of the actuator system, with a deviation, for example in the form of a difference, between the position-resolved actual contact force and the position-resolved reference contact force being minimized as a control criterion.

The procedural steps 104 to 106 are repeated until the mobile transport device has arrived at the destination.

The procedure is then ended 107 .

It can be in process step 102 It can be provided that after the at least one transport item has been arranged on the transport platform, a reference run is carried out, with an acceleration being estimated and / or detected by means of at least one acceleration sensor during the reference run, and a position-resolved reference value being generated during the reference run by means of the at least two force sensors. Contact force is detected, and a center of gravity of the at least one transport item is estimated from the estimated and / or detected acceleration and the position-resolved reference contact force, and the inclination of the transport platform is regulated additionally or alternatively on the basis of the estimated center of gravity.

Furthermore, it can be provided that for regulating the inclination in method step 106 two control structures running in parallel are used, with one of the control structures minimizing a deviation, for example a difference, between the position-resolved actual contact force and the position-resolved reference contact force by changing the inclination in relation to one of two degrees of inclination freedom as a control criterion, and the other control structure as a control criterion, the deviation or the difference between the position-resolved actual contact force and the position-resolved reference contact force is minimized by changing the inclination in relation to another of the two degrees of freedom of inclination.

In 3 Figure 3 is a schematic representation of an exemplary embodiment of a rule structure 40 for controlling an inclination of the transport platform is shown. The rule structure 40 includes a rule structure 41 for the inclination in relation to a first degree of inclination freedom, that is to say in relation to the x-axis and a rule structure 42 for the inclination with respect to a second degree of inclination freedom, i.e. with respect to the y-axis. It is regulated in both control structures 41 , 42 each by means of a PID controller 43 . The actuators 44 are each actuators 6-1 , 6-2 , 6-3 , 6-4 to influence an inclination in relation to the x-axis and actuators 6-1 , 6-2 , 6-3 , 6-4 for influencing an inclination with respect to the y-axis.

To regulate the inclination in relation to the x-axis, two of the actuators are used 6-1 , 6-2 , 6-3 , 6-4 when regulating in pairs to groups 45 , 46 summarized. The group 45 includes the actuators 6-1 and 6-4 , the group 46 the actuators 6-2 and 6-3 . The ones in the groups 45 , 46 each included actuators 6-1 , 6-2 , 6-3 , 6-4 are controlled in the same way so that an inclination can only be regulated or changed along the x-axis. To regulate the inclination in relation to the y-axis, two of the actuators are used 6-1 , 6-2 , 6-3 , 6-4 when regulating in pairs to groups 47 , 48 summarized. The group 47 includes the actuators 6-1 and 6-2 , the group 48 the actuators 6-3 and 6-4 . The ones in the groups 47 , 48 each included actuators 6-1 , 6-2 , 6-3 , 6-4 are controlled in the same way so that an inclination can only be regulated or changed along the y-axis.

For every group 45 , 46 , 47 , 48 becomes a control signal 61 , 62 , 63 , 64 generated and provided.

The control signals provided for control with reference to the x-axis and for control with reference to the y-axis are described below 61 , 62 , 63 , 64 for each of the actuators 6-1 , 6-2 , 6-3 , 6-4 summed up and for controlling the individual actuators 6-1 , 6-2 , 6-3 , 6-4 used.

The respective controlled systems 49 , 50 of the rule structures 41 , 42 include the slope 51 , 52 of the transport platform in relation to the x-axis or the y-axis, with one deviation in each case 53 , 54 between a reference contact force and an actual contact force with respect to the x-axis and the y-axis is determined and minimized as a control criterion. The reference contact force and the actual contact force are measured with the aid of force sensors arranged in matrix form on the transport platform 3 determined and broken down into reference contact force and actual contact force with reference to the x-axis and the y-axis.

In particular, the control concept is repeatedly based on the respective force sensor at each point in time 3 with the largest amount of deviation between the reference contact force and the actual contact force. This means that the transport platform is inclined or lowered or raised with the correct sign in the direction in which the greatest deviation from the reference contact force can be determined.

The definite deviations 53 , 54 are then the PID controllers 43 fed.

List of reference symbols

1

mobile transport device

2

Transport platform

3

Force sensor

4th

Mode of Transport

5

wheel

6th

Actuators

6-1

Actuator

6-2

Actuator

6-3

Actuator

6-4

Actuator

7th

Linear motor

8th

control

9

Accelerometer

10

Cargo

11

distance

12

ground

13

main emphasis

14th

Tilt sensor

15th

Deflection (actuator)

20th

Reference vertical force at rest

20 '

Reference contact force during the reference run

21st

Actual insurgency

22nd

acceleration

23

Tilt

30th

Rotation axis (x-axis)

31

Rotation axis (y-axis)

32

Degree of freedom of inclination

33

Degree of freedom of inclination

40

Rule structure

41

Control structure (x-axis)

42

Control structure (y-axis)

43

PID controller

44

Actuator

45

group

46

group

47

group

48

group

51

Tilt

52

Tilt

53

deviation

54

deviation

61

Control signal

62

Control signal

63

Control signal

64

Control signal

100-107

Procedural steps

200

Process step

Claims (10)

A method for transporting at least one transport item (10), comprising the steps: Arranging the at least one transport item (10) on a transport platform (2) of a mobile transport device (1), Detection of a position-resolved reference contact force (20) of the at least one transported goods (10) arranged on the transport platform (2) by means of at least two force sensors (3) when the transport device (1) is in a state of rest, Regulation of an inclination (23) of the transport platform (2) by means of an actuator (6), with a position-resolved actual contact force (21) of the at least one transport item (10) arranged on the transport platform (2) by means of the at least two force sensors ( 3) is recorded, and wherein at least as a control criterion a deviation between the position-resolved actual contact force (21) and the position-resolved reference contact force (20) is minimized. Procedure according to Claim 1 , characterized in that the position-resolved reference contact force (20) and the actual contact force (21) are detected by means of force sensors (3) which are arranged in the form of a matrix at regular intervals on or on the transport platform (2). Procedure according to Claim 1 or 2 , characterized in that after the at least one transport item (10) has been arranged on the transport platform (2), a reference travel is carried out, an acceleration (22) being estimated and / or by means of at least one during the reference travel an acceleration sensor (9) is detected, and a position-resolved reference contact force (20 ') is detected during the reference run by means of the at least two force sensors (3), and from the estimated and / or detected acceleration (22) and the position-resolved reference - Uprising force (20 ') of the reference run, a center of gravity (13) of the at least one transport item (10) is estimated, and the regulation of the inclination (23) of the transport platform (2) additionally or alternatively takes place on the basis of the estimated center of gravity (13). Method according to one of the preceding claims, characterized in that two control structures running in parallel are used to control the inclination (23), one of the control structures being a deviation between the position-resolved actual contact force (21) and the position-resolved reference contact force (20) as a control criterion ) at rest by changing the inclination (23) with respect to one of two inclination degrees of freedom (32, 33), and the other control structure as a control criterion is the deviation between the position-resolved actual contact force (21) and the position-resolved reference contact force (20 ) is minimized by changing the inclination (23) with respect to another of the two inclination degrees of freedom (32, 33). Method according to one of the preceding claims, characterized in that before the position-resolved reference contact force (20) is recorded in the resting state, an inclination (23) of the transport platform (2) is recorded by means of an inclination sensor (14) and corrected by means of the actuator system (6) becomes. Mobile transport device (1) for transporting at least one transport item (10), comprising: a transport platform (2), a transport means (4) for moving the transport platform (2), at least two force sensors (3) arranged on the transport platform (2) for detecting a position-resolved contact force (20, 21) of at least one transport item (10) arranged on the transport platform (2), an actuator (6) for setting an inclination (23) of the transport platform (2), and a controller (8), wherein the controller (8) is designed to regulate the inclination (23) of the transport platform (2) by means of the actuators (6) and at least as a control criterion a deviation between a position-resolved actual value detected during transport To minimize contact force (21) of the at least one transport item (10) arranged on the transport platform (2) and a position-resolved reference contact force (20) of the at least one transport item (10) arranged on the transport platform (2), which is detected in a state of rest. Mobile transport device (1) according to Claim 6 , characterized in that the at least two force sensors (3) are arranged in the form of a matrix at regular intervals on or on the transport platform (2). Mobile transport device (1) according to one of the Claims 6 or 7th , characterized in that the controller (8) is further designed to control the transport means (4) in such a way that after the at least one transport item (10) has been arranged on the transport platform (2), a reference travel is carried out, and an acceleration (22 ) to estimate the transport platform (2) during the reference run and to estimate a center of gravity (13) of the at least one transport item (10) from a position-resolved reference contact force (20 ') recorded during the reference run and the estimated acceleration (22), and the regulation the inclination (23) of the transport platform (2) additionally or alternatively on the basis of the estimated center of gravity (13). Mobile transport device (1) according to Claim 8 , characterized by at least one acceleration sensor (9) for detecting an acceleration (22) of the transport platform (2), wherein the controller (8) is further designed in such a way that the center of gravity (13) of the at least one transport item (10) is additionally or alternatively based on to estimate an acceleration (22) of the transport platform (2) detected by means of the acceleration sensor (9) during the reference run. Mobile transport device (1) according to one of the Claims 6 to 9 , characterized by an inclination sensor (14) for detecting an inclination (23) of the transport platform (2), wherein the controller (8) is further designed in such a way, before the detection of the reference contact force (20), the actuator system (6) on the basis of a to control the detected inclination (23) of the transport platform (2) so that the detected inclination (23) of the transport platform (2) is corrected.

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