EP4185754B1 - Method for carrying out a construction process when erecting a building using at least one construction robot - Google Patents

Description

The invention relates to a method for carrying out a construction process when erecting a building using at least one construction robot with sensory detection of existing dimensional deviations as well as integrated processing and adjustment of the corresponding workpieces in the automated execution of construction processes (e.g. laying walls or tiling) using a mobile construction robot.

The invention relates in particular to all methods in which the compensation of workpiece tolerances is not possible through averaged workpiece positioning or joint dimension adjustment and which are carried out directly on the construction site.

Due to manufacturing and process reasons, dimensional and positional deviations arise in many construction processes (e.g. laying bricks and tiles). This are caused, among other things, by tolerances in the length, width and height dimensions of the individual workpieces, as well as tolerances in the butt and bed joints between the workpieces. Overall, these individual deviations can lead to the permissible upper and lower dimensions specified in the construction plan being exceeded or fallen short of. In order to comply with the permissible dimensional tolerances, it is necessary to regularly record and check the current dimensions and, if necessary, to adapt the workpieces through subtractive or additive processing (e.g. cutting, breaking, burning, sawing, milling, applying).

Previous mobile devices or robot systems for the automated laying of bricks, tiles or similar objects do not check the tolerance chain or compliance with the permissible dimensions. The objects to be moved are simply lined up next to each other. The positioning and alignment of the objects is done either in relation to the objects that have already been laid (e.g. by checking the gap and joint dimensions) or by specifying absolute position and location values (related to a reference system, e.g. construction site coordinate system). Due to the dimensional deviations, absolute position measuring systems are only used for rough positioning. Here, too, fine positioning is carried out using a relative measuring method or by checking the contact pressure when laying the workpieces.

Systems with integrated facilities for cutting workpieces already exist. With these systems, the cutting is done solely on the basis of the planning data defined by the construction plan.

With the existing mobile construction robotics systems (such as the system from WO2018/063100A2 ) compliance with the permissible tolerances cannot be guaranteed. On the one hand, this is because the actual dimensions of the respective structure and workpieces are not regularly measured and compared with the nominal dimensions and permissible tolerances. On the other hand, the workpieces are not adjusted depending on the current dimensional deviations. Practical use, in which construction must be carried out in accordance with applicable standards and guidelines (e.g. DIN 18202 - tolerances in building construction), cannot be guaranteed with the previous solutions.

The object of the invention is therefore to enable compliance with the permissible tolerances in the automated laying or assembly of workpieces using mobile construction robots in the construction sector.

According to the invention, this object is achieved with a method which has the features of claim 1. Advantageous developments and embodiments can be realized with features specified in dependent claims.

To solve the task, a process sequence is defined, which includes checking and monitoring the permissible tolerances as well as the machining of the workpieces. In addition, possible technical solutions for implementing the individual process steps are described.

In the invention, a construction process is carried out using at least one mobile construction robot, which is designed to lay and/or assemble workpieces to produce a construction object.

A digital construction plan or a digital construction object model is stored in an electronic evaluation and control unit, which contains the nominal dimensions and dimensional tolerances of the respective construction object.

In the electronic evaluation and control unit, at least the relevant external dimensions of workpieces for the respective construction project and, if necessary, also physical properties (dimensions, mass, position, etc.) of workpieces that are relevant for the respective construction object are stored for the construction project.

Using at least one sensor or a sensor device, the current actual dimensions of the respective construction project are determined and fed to the electronic evaluation and control unit.

At least one mobile construction robot is used to search for a workpiece to be subsequently installed in the respective construction process. Data from the digital building object and one or more sensors can be used.

After locating the workpiece to be subsequently installed, at least one further sensor or sensor device is used to determine the external dimensions of the workpiece relevant to the construction process and thus calculate any dimensional deviations that occur from a target value when laying and/or assembling the respective workpiece. The determined dimensional deviations are used to decide whether the respective workpiece is laid and/or assembled at a position corresponding to the construction project model or whether it is processed in advance so that its external dimensions lie within dimensional tolerances after laying and/or assembly at the respective position.

The respective actual dimensions can advantageously be determined in a contact or preferably non-contact manner.

When deciding whether or not a workpiece is processed before laying and/or assembly, dimensional tolerances stored in the digital construction project should be taken into account.

The main novelty of the invention is the combination of sensory recording of the actual dimensions of the construction project (structure) and workpiece, the determination and calculation of the dimensional deviations, the control of the permissible tolerances and the adjustment of the workpieces depending on the results of a dimensional tolerance analysis.

The invention forms the prerequisite for maintaining the permissible tolerance dimensions in the automated execution of construction processes using mobile robot systems and thus creates the basis for the practical use of future construction robotics systems. By describing a generally valid process sequence, a wide range of potential applications is covered (e.g. laying bricks, aerated concrete blocks, tiles, paving slabs, paving stones, drywall, etc. as possible workpieces).

Before the laying or assembly process, information about what is to be installed is created from a digital construction plan or building model Workpiece loaded. This can include, among other things, the type, geometry, material or type designation of the workpiece. Using this information, the robot or a separate conveyor unit can search for a suitable workpiece (e.g. on a pallet or in a material warehouse).

The actual geometric dimensions and/or shape of the respective workpiece are then recorded using suitable sensors. This can be done, among other things, by using laser distance sensors, laser cutting sensors, lidar sensors, ultrasonic sensors, depth imaging cameras, cameras or touch sensors. The corresponding sensors can be arranged on the manipulator of the construction robot or on a base platform. The individual dimensions can be determined before or after the workpiece is picked up by the construction robot. The search for a respective workpiece can also be carried out using the sensor or the sensor device.

The current actual dimensions of the construction object can be determined either by the sensors of the construction robot or a separate measuring device (e.g. tachymeter or an unmanned flying object/drone). Suitable sensors can be present there for this purpose.

Using the nominal dimensions of the construction object, which are contained in the digital construction project model, as well as the actual dimensions of the construction object and workpiece, the dimensional deviations after the respective workpiece has been laid or assembled can be calculated before the respective workpiece is laid and/or assembled. For this purpose, information about the construction process can be included, which, among other things, provides information about the joint and gap dimensions. The information about the construction process can also be part of the digital construction plan or construction project model, but can also be defined separately. Alternatively, the information on the joint and gap dimensions can also be included in the nominal dimensions. Based on the calculated dimensional deviations and the permissible dimensional tolerances, which are also stored in the digital construction plan or construction project model, a decision is made as to whether the workpiece will be processed or not. Various criteria can be used to make the decision, which also take into account the uncertainties of the actual dimensions determined and the calculated dimensional deviations.

There is also the possibility of taking into account the values that were detected during the determination of the actual dimensions with the at least one further sensor or sensor device and comparing them with the corresponding nominal dimensions, taking into account tolerance dimensions of the digital construction project, in order to determine whether a respective workpiece must be installed before laying and/or or assembly is processed or not.

If it is decided that the workpiece needs to be adjusted, it is adjusted using one or more processing devices, which can be integrated on the construction robot. After machining, the workpiece can be measured again for the purposes of machining control and, if necessary, machined again (iterative process). The workpiece is then installed by the robot.

Claims (6)

1. A method for carrying out a construction process when erecting a structure using at least one mobile construction robot, which is designed to install and/or assemble workpieces for producing a building, in which

   a digital construction plan or a digital building model, in which nominal dimensions and dimensional tolerances of the particular building are contained, is stored in an electronic evaluation and control unit; and

   at least the outer dimensions of workpieces for the construction project which are relevant for the particular building are stored in the electronic evaluation and control unit; and

   the instantaneous actual dimensions of the particular construction project are determined by means of at least one sensor or a sensor device and are supplied to the electronic evaluation and control unit; and

   the search for a workpiece to be subsequently used in the particular construction process is carried out by way of the at least one mobile construction robot by means of data of the digital building model, wherein

   the outer dimensions of the workpiece that are relevant for the construction process being determined by way of at least one further sensor or sensor device after the workpiece to be subsequently mounted having been located and, with this, dimensional deviations from a target value which occur during an installation and/or assembly of the particular workpiece being calculated, and a decision being made based thereon as to whether the particular workpiece is installed and/or assembled in a position that corresponds to the construction project model or whether it is first processed so that the outer dimensions thereof are within dimensional tolerances after having been installed and/or placed in the particular position.
2. The method according to claim 1, characterized in that the determination of the actual data is carried out in a non-contact or contact manner.
3. The method according to any one of the preceding claims, characterized in that dimensional tolerances stored in the digital construction project are taken into consideration in a decision as to whether or not a workpiece is processed prior to installation and/or assembly.
4. The method according to any one of the preceding claims, characterized in that at least one laser distance sensor, a laser cutting sensor, a LIDAR sensor, an ultrasonic sensor, a depth image camera, a camera or a touch sensor is used as the sensor or sensor device.
5. The method according to any one of the preceding claims, characterized in that a further sensor or sensor device for absolute measurement is present at a stationary or mobile object, in particular a tripod or an unmanned aerial vehicle, by way of which the determination of actual dimensions at the building is carried out.
6. The method according to any one of the preceding claims, characterized in that joint dimensions and clearances that were detected during the actual dimension ascertainment by way of the at least one further sensor or sensor device are taken into consideration and, taking tolerance dimensions of the digital construction project into consideration, are compared to corresponding nominal dimensions so as to determine whether or not a particular workpiece is processed prior to installation and/or assembly.