阅读说明：本技术 用于借助自适应保护区域保护移动的物流机器人的工作区域的方法 (Method for protecting a working area of a mobile logistics robot by means of an adaptive protection area ) 是由 D·舒特 A·本特 R·柯尼希 于 2019-09-19 设计创作，主要内容包括：本发明涉及一种用于在变换的工作环境(A)中保护移动的物流机器人的工作区域(B)的方法,其中,物流机器人由控制系统控制,并且当前的工作环境(A)借助传感器系统检测并且由安全系统监测。本发明提出,控制系统在新的工作环境(A)中自主地定义意图的、安全的工作区域(B),并且安全系统自主地将已定义的工作区域(B)作为自由的保护区域(S,1,2,3,4)验证并且监测,并且在由于物体(O)进入到自由的保护区域(S,1,2,3,4)中而侵犯保护区域时自动地使物流机器人处于安全状态中。(The invention relates to a method for protecting a work area (B) of a mobile logistics robot in a changed work environment (A), wherein the logistics robot is controlled by a control system, and the current work environment (A) is detected by means of a sensor system and monitored by a safety system. The invention proposes that the control system autonomously defines an intended, safe working area (B) in the new working environment (A), and that the safety system autonomously verifies and monitors the defined working area (B) as a free protection area (S, 1, 2, 3, 4) and automatically puts the logistics robot into a safe state when the protection area is violated by an object (O) entering the free protection area (S, 1, 2, 3, 4).)

1. Method for protecting a work area (B) of a mobile logistics robot in a changed work environment (a), wherein the logistics robot is controlled by a control system and the current work environment (a) is detected by means of a sensor system and monitored by a safety system, characterized in that the control system autonomously defines an intended, safe work area (B) in a new work environment (a) and the safety system autonomously verifies and monitors the defined work area (B) as a free protection area (S, 1, 2, 3, 4) and automatically puts the logistics robot in a safe state when violating a protection area due to an object (O) entering the free protection area (S, 1, 2, 3, 4).

2. Method according to claim 1, characterized in that the control system transmits a mathematical description of the defined working area (B) to the safety system.

3. Method according to claim 1, characterized in that the control system selects a protection area (S, 1, 2, 3, 4) from a predefined set of protection areas (S, 1, 2, 3, 4) which covers the intended, safe working area (B).

4. Method according to claim 1, characterized in that the control system applies iteratively a predefined set of protection zones (S, 1, 2, 3, 4) to the working environment (a), wherein the following algorithm is used:

1) a small protection area i is selected and,

2) verifying by the security system whether the protected area i is free,

2a) upon verification as a free protection zone i: continuing with step 3),

2b) upon verification as an occupied protection zone: the process is stopped, and the process is stopped,

3) the next larger protection area i is selected,

4) continuing with step 2),

5) the most probable protection zone is defined as protection zone i-1 of the protection zone that is finally verified as free.

5. The method according to any of claims 2 to 4, characterized in that the predefined set of protection areas (S, 1, 2, 3, 4) comprises rectangular protection areas (S, 1, 2, 3, 4).

6. Method according to any of claims 1 to 5, characterized in that the free protection zone (S, 1, 2, 3, 4) is so close to the defined contour of the working zone (B) that a person cannot stay in the gap.

7. Method according to claim 6, characterized in that the free protection zone (S, 1, 2, 3, 4) is so close to the defined contour of the working zone (B) that a maximum of 10cm of spacing remains between the free protection zone (S, 1, 2, 3, 4) and the defined contour.

8. Method according to any of claims 1 to 7, characterized in that a plurality of free protection zones (S, 1, 2, 3, 4) are combined.

9. The method according to any one of claims 1 to 8, characterized in that the control system defines the intended, safe working area (B) by evaluating the sensor data.

10. Method according to any one of claims 1 to 9, characterized in that at least one sensor designed as a scanner scans the working environment (a).

11. Method according to claim 10, characterized in that a laser scanner is used as sensor.

12. Method according to any one of claims 1 to 11, characterized in that a mobile robotic vehicle, in particular an autonomous ground conveyance, with at least one robotic arm for handling in a changed work environment (a) is used as logistics robot, wherein the control system controls at least the robotic arm.

13. Method according to any of claims 1 to 12, characterized in that a non-safety control system is used as a control system, the control measures of which are monitored by the safety system.

14. Method according to any one of claims 1 to 12, characterized in that a safety control system is used as a control system, into which the safety system is integrated.

Technical Field

The invention relates to a method for protecting a working area of a mobile logistics robot in a changed working environment, wherein the logistics robot is controlled by a control system, and the current working environment is detected by means of a sensor system and monitored by a safety system.

Background

Robots are increasingly used in the industrial and logistics industry for automating processes in industrial manufacturing as well as in logistics tasks, such as sorting. In this case, robots with a robot arm, in particular a robot arm, are mainly used. An example of this is the so-called robot with a bendable arm.

Robot applications of robotic arms in today's industrial automation usually operate in a separate workspace, which is usually designed as a safety cage monitored by sensors. The first collaborative robot solution in the prior art is implemented as a current further development, wherein the human and the robot work in the same working environment. However, for safety reasons, the operating speed is strongly limited in the robot solution. The so-called cooperative speed is typically at most 250 mm/s. Furthermore, the robot solution has very high manufacturing costs due to the necessity of safety-related force and moment sensing technology. Furthermore, only very small payloads (in the range of less than a kilogram) can typically be lifted, thereby adversely affecting the payload to self-load ratio.

A major part of today's robot solutions can be characterized as stationary robot solutions, since the robot arm is either immovably fixed on the ground or movably mounted on a linear axis. This results in a spatially very confined working space, which is usually separated by a safety fence.

There is a mobile first solution with an arm on a freely movable platform robot. Examples of this are flat, automatically guided vehicles ("AGVs") or unmanned ground transport vehicles, in particular mobile picking robots. However, said solutions cannot generally be used in hybrid operation without spatial isolation from the operator.

A first solution of a virtual protective fence is implemented as a variant of a fixedly arranged safety fence, wherein the free area surrounding the robot is monitored by means of suitable sensors (e.g. laser scanners). The robot is safely restrained or shut down while violating the protection zone defined by the virtual protection fence.

Barriers that hinder the use of a co-operating scheme with human-robot cooperation arise by spatially isolating the robots from the human. Mixed operation in areas where people and robots are used in parallel is often not possible also in the case of mobile robot units, for example mounted on movable platforms. The solution with the kinematics adapted to the application, which avoids risks by shaping the robot housing, strongly limits the design freedom of the kinematics.

The results of these obstacles show that only a very limited field of application is achieved for the known characteristic-dependent collaborative robot solutions. The collaborative robot solution therefore currently only achieves very low market penetration.

The implementation of a coordination solution in the case of a logistics robot, in particular an autonomous ground transport vehicle, for example a mobile picking robot, with a robot arm for loading and unloading is particularly demanding, since the logistics robot should be free to move in a logistics area, for example a storage warehouse. The logistics robot is here constantly exposed to completely new working environments, which must be secured.

Disclosure of Invention

The object of the present invention is to design a method of the type mentioned at the outset such that a safe and reliable operation of a mobile, freely movable logistics robot is possible even in a changing work environment in a hybrid operation with humans.

This object is achieved according to the invention in that the control system autonomously defines an intended, safe working area in the new working environment, and the safety system autonomously verifies and monitors the defined working area as a free protection area and automatically puts the logistics robot into a safe state when the protection area is violated by an object entering the free protection area.

The method according to the invention thus enables a secure protected area to be autonomously identified for a new work environment and to be monitored by the security system. In contrast to conventional, fixedly arranged security fences and fixedly adjusted virtual protection fences, the adaptive protection zones according to the invention can be adapted continuously to different working environments.

In a preferred embodiment of the invention, the control system transmits a mathematical description of the defined working area to the safety system.

It is advantageous here that the electronic control system of the logistics robot itself does not need to be safe. That is, a conventional robot arm control device may be used, for example. The safety protection is carried out by a safety system, which can be designed as an electronic safety control system of its own.

Expediently, the non-safety control system scans the working environment by means of sensors and defines the intended, safe working area. The non-safety control system then transmits the intended safe working area as a mathematical description (preferably as a polygon) to the safety system, which is defined as a safety sensor preferably designed as a scanner. The safety sensor may also be the same sensor as in the case of scanning the working environment by means of the non-safety control system. The security system confirms that the protected zone is free (i.e., unoccupied).

A variant of the invention provides that the control system selects a protection zone from a predefined set of protection zones, which covers the intended, safe working area.

Here, the non-safety control system also scans the working environment by means of sensors and selects a protective zone from a predefined set of protective zones, which covers the intended, safe working area and satisfies the identified contour of the intended, safe working area in a suitable manner. The non-safety control system then transmits the intended safe working area to the safety system, which is defined as a safety sensor preferably designed as a scanner. The safety sensor may also be the same sensor as in the case of scanning the working environment by means of the non-safety control system. It is confirmed that the protection area is free (i.e., unoccupied).

Non-safety control systems may also be used for this purpose. The non-safety control system selects a protection zone from a predefined set of protection zones that satisfies the identified contour of the intended work zone in a suitable manner. The contour of the protective region can be arbitrary here. Without limiting the generality, rectangular protective regions can be used in particular.

The aforementioned solution provides, in particular, a control system which is formed from non-safety control systems, such as robot controllers and (monitored) safety systems. This division is expedient since safety control systems generally have an extremely limited functional range and therefore do not allow more complex algorithms to be described therein.

The variants described below reduce the algorithm complexity, so that the method according to the invention can also be implemented on a more simply structured safety control system.

Instead of scanning the working environment to be able to define a suitable protection area, a simplified solution proposes to apply a fixedly defined set of protection areas iteratively to the transformed working environment by the security system.

One advantageous variant of the invention therefore relates to a method in which the control system iteratively applies a predefined set of protection zones to the working environment, wherein the following algorithm is used:

1. a small protection area i is selected and,

2. it is verified by the security system whether the protected area i is free,

2.1 when verifying a protection zone i that is free: and the step 3 is continued to be carried out,

2.2 when verifying as occupied protection zone: the process is stopped, and the process is stopped,

3. the next larger protection area i is selected,

4. and the step 2 is continued to be carried out,

5. the most probable protection zone is defined as protection zone i-1 of the protection zone that is finally verified as free.

In this case, the predefined set of protection regions comprises rectangular protection regions, in accordance with the destination. However, depending on the characteristics of the working environment, the predefined set of protection areas may also have protection areas that are otherwise suitably shaped.

In a further development of the inventive concept, the free protective region is so close to the defined contour of the working region that a person cannot stay in the gap.

That is, this further solution provides that the protection zone is very close to the defined contour. Thereby leaving only a small unmonitored area. According to the existing criteria, the unmonitored area must be selected such that a person cannot stay in the unmonitored area. This is achieved by this further development in that the adaptive protection region is defined such that the unmonitored protection space remains below the limits specified in the standard.

The free protective region is preferably so close to the defined contour of the working region that a maximum spacing of 10cm remains between the free protective region and the defined contour.

By the method according to the invention, a continuous, gap-free guard region can be generated and verified, which can be defined by means of a curved path, which is preferably predefined by a polygon. In a further embodiment of the invention, a plurality of free guard areas are combined. This results in discrete protective regions, which can thus also have gaps.

In a practical embodiment of the invention, the control system defines the intended, safe working area by evaluating the sensor data. For this purpose, at least one sensor designed as a scanner preferably scans the operating environment. Expediently, laser scanners are used as sensors.

A preferred application of the invention provides that a mobile freely movable robot vehicle, in particular an autonomous ground transport vehicle, having at least one robot arm for loading and unloading in an alternative working environment is used as a logistics robot, wherein the control system controls at least the robot arm.

In this case, advantageously, a non-safety control system is used as a control system, the control measures of which are monitored by the safety system.

A further expedient variant of the invention provides for the use of a safety control system as a control system, into which the safety system is integrated.

The invention achieves a series of advantages:

working areas without fixed protection area isolation devices can be exploited.

Furthermore, the working speed can be increased, since the robots can move at "uncoordinated" speeds. In addition, increased payload can be handled, since continuous force and moment monitoring of the robot is not required and thus larger payloads can be moved at increased speeds, which are greater than the monitoring limit. The cost of the sensors can also be reduced since there is no need for cooperative monitoring by robot-mounted sensors. Finally, the cost of the robot arm can also be reduced, since standard industrial robots can be used instead of cost-intensive coordinated robots.

Drawings

Further advantages and details of the invention are explained in more detail on the basis of the embodiments shown in the schematic drawings. In the drawings:

figure 1 shows the definition of a protection zone in an adaptively protected working environment,

FIG. 2 illustrates a predefined set of protection zones in an adaptively protected work environment, an

Fig. 3 shows the selection of the maximum unoccupied protection zone for protecting the working environment of the robot.

Detailed Description

Fig. 1 shows the definition of a protected area S in an adaptively protected operating environment a. In this example, the protection region S is defined by a polygon S. For this purpose, the non-safety control system of the logistics robot, not shown in fig. 1, scans the working environment a by means of sensors and defines the intended, safe working area B. As shown in fig. 1, a working area B is selected which is not occupied by the object O, i.e. in this case a pallet O. The non-safety control system then transmits the intended safe working area B as a mathematical description (here as polygon S) to the safety system, which is defined as a safety sensor, in particular designed as a scanner. The security system confirms that the protected area S is free (unoccupied).

In fig. 2a set of predefined protection zones 1, 2, 3, 4 is shown. The protective regions 1, 2, 3, 4 have a rectangular shape, for example. For this purpose, the non-safety control system of the logistics robot, not shown in fig. 2, scans the working environment a by means of sensors and defines the intended, safe working area B. The protective areas 1, 2, 4 are free, i.e. unoccupied, while the protective area 3 is occupied by an object O, i.e. in this case a pallet O. The non-safety control system of the logistics robot, not shown in fig. 2, selects a protection area 1, 2, 4 from a predefined set of protection areas 1, 2, 3, 4, which in a suitable way satisfies the identified contour of the intended work area B. The non-safety control system then transmits the unoccupied protected area 1, 2, 4 to the safety system, which is defined as a safety sensor, in particular designed as a scanner. The security system confirms that the protected areas 1, 2, 4 are free (unoccupied).

Fig. 3 shows that the largest unoccupied protection zones 1, 4 are selected as with the iterative method. Here, the control system of the logistics robot, not shown in fig. 3, iteratively applies a predefined set of protection zones to the work environment a. In the present example, the same set of protection regions 1, 2, 3, 4 as in fig. 2 is involved, wherein only the result of the iterative method is shown in fig. 3. A small protection area is first selected. It is verified by the security system whether the protected area is free. If free, the next larger protection zone is selected. This process is carried out so long until the maximum possible protection zone is defined as the protection zone of the protection zone that is finally verified as free. In the present example, the largest possible protection areas are protection areas 1 and 4, which are not occupied by an object O, here a pallet O.