SERVICE STATION FOR MOBILE ROBOTS

Description

[0001] The invention relates to a service station for mobile robots with a device for electrically charging the batteries.

[0002] From DE 20 2009 018 986 U1, a service station is known to which a service robot can independently dock and supply itself with utilities.

[0003] Service robots are known to charge their batteries by autonomously docking at a station.

[0004] To efficiently extend the autonomous operation of a cleaning robot, it is not enough for the batteries to recharge automatically. In addition to electrical energy, the cleaning robot also needs water and must empty its dirty water tank.

[0005] From WO2005055795A1 a self-propelled or transportable sweeping device with a sweeping brush and an associated dirt collection chamber is known, in which a sweeping device of the type in question is to be designed in such a way that it enables complete cleaning compared to the known devices, a liquid application device is proposed which is arranged behind the sweeping brush in the direction of travel and a dehumidification device arranged further behind it.

[0006] The object of the invention is to provide an improved service station that enables both electricity and water transmission.

[0007] This task is solved by a service station for mobile robots according to the features of claim 1.

[0008] According to the invention, a service station for mobile robots is provided with the possibility of electrically charging the batteries, wherein this station has provisions for localization support and / or provisions for compensating for residual positioning inaccuracies. wherein the residual deviation present during positioning is compensated by a conical mandrel attached to the service station and a guide element attached to the mobile robot, wherein the mandrel has a clearance fit relative to the guide; elastic buffer elements are provided to correct the angular offset, and the part of the service station on which the mandrel and couplings are mounted is mounted on a linearly movable carriage, and that the angular offset can be compensated for by elastic buffer elements.

[0009] It is advantageous that the service station has a transfer option for refilling with fresh water or premixed cleaning fluid, and / or a possibility for draining and / or pumping out the wastewater, whereby The supply of fresh water is pumped into the fresh water tank using line pressure, and the wastewater is collected by the service station and discharged into a drain.

[0010] Preferably, it is provided that this has an additional transfer option for cleaning agents.

[0011] Preferably, the service station includes a device for automatically pumping out the dirty water from the mobile robot and an additional transfer option for cleaning agents. One embodiment provides that it has a device for cleaning one or more squeegee lips.

[0012] According to a further aspect of the invention, a service station for mobile robots is proposed, wherein this station incorporates provisions for changing brushes and / or processing tools. The necessary actuator movements can be performed by the robot and / or the service station.

[0013] In addition, the service station is able to transfer data, clean the suction lip, and replace the brushes.

[0014] According to the invention, a full-service station is proposed which allows an autonomous cleaning robot to perform its tasks independently over an extended period. In addition to automated battery charging, this requires, in particular, the automated pumping out of the dirty water and the automated filling of fresh water and cleaning agents.

[0015] Furthermore, due to the soiling of the suction lip on the cleaning robot during operation, it remains necessary to allow cleaning at the service station. Otherwise, the cleaning result would be unacceptable due to streaking.

[0016] Another essential feature of the invention is an automated brush changing device at the service station, which enables the robot to renew the brushes in case of wear or to meet changed cleaning requirements on the object during longer autonomous operation when changing the brushes and / or pads.

[0017] According to the invention, the measures required for the automatic process at the service station include features such as localization support and compensation for remaining positioning and orientation errors.

[0018] To implement this improvement, water must be exchanged between the service station and the robot. To minimize leakage, precise positioning of the service robot relative to the service station is essential. Therefore, the technical effort is significantly higher compared to simple electrical charging stations and can only be achieved by combining the following subtasks.

[0019] Further advantageous embodiments result from the further dependent claims or their possible subcombinations.

[0020] The invention is further explained below with reference to the drawings. Specifically, the schematic representation in: Fig. 1 a schematic side view of a cleaning robot, Fig. 2 a schematic view of a cleaning robot from below, Fig. 3 a schematic representation of the compensation for positional inaccuracies, Fig. 4 a schematic representation of the compensation for angular misalignment, Fig. 5 a schematic representation of the dirty water transfer, Fig. 6 a schematic representation of the position contacts, Fig. 7 a schematic representation of the coding of the charging contacts, Fig. 8 a schematic representation of the cleaning of the suction lip, Fig. 9 a schematic representation of brush changing unit 1, Fig. 10 a schematic representation of brush changing unit 2, and Fig. 11 a schematic representation of brush changing unit 3.

[0021] The identical reference numbers in the figures denote identical or similarly acting elements.

[0022] The cleaning robot consists of various components. The elements relevant to the patent application are described below.

[0023] The Figs. 1 and 2 Shows a cleaning robot seen from the side and from below.

[0024] To ensure the robot is positioned as accurately as possible relative to the service station, the service station is equipped with significant features. These features can include, for example: A distinct geometric shape, such as an angle, curve, corner, etc. This geometrically unambiguous shape can be easily recognized through distance measurements, allowing the robot to calculate its position relative to the service station and determine a suitable path to approach the station. Highly reflective surfaces such as reflectors or mirrors. Reflectors can be readily identified with laser scanners because the intensity of the reflected beams is significantly higher than with normal surfaces. Mirrors, on the other hand, only reflect light when the emitted beam strikes the mirror at a right angle. If the beam hits the mirror at a different angle, there is no feedback to the laser scanner. These non-reflective zones can thus be clearly identified. Signal-generating elements such as ultrasonic sensors.For example, if at least two ultrasonic sensors are mounted on the station and at least two on the vehicle, these can be synchronized via radio to determine the distances between them. This allows the robot's position and orientation relative to the station to be calculated unambiguously. With fewer sensors, a position determination that is insufficient based on a single measurement can be performed by the robot itself to unambiguously calculate its position between the robot and the station. Optical codes, such as barcodes or QR codes, can be reliably detected and located using a camera. Based on these codes, the robot's position relative to the service station can be determined, and a path to approach the service station can be calculated.

[0025] Positioning inaccuracies can cause a lateral and angular misalignment between the robot and the service station when the robot docks.

[0026] The compensation for lateral misalignment takes place in two stages. When approaching the service station, the robot, with its castor wheel, travels in a tapered track that is rigidly connected to the service station. While traveling in the track, the robot is controlled based on the resistance encountered upon contact with the track. This is achieved by the robot attempting to regulate the increasing motor currents upon contact by counter-steering. In the second stage, a tapered mandrel attached to the service station engages with a guide mounted on the robot. The mandrel has a clearance fit with the guide. Since it is not possible to compensate for these minute inaccuracies via the robot's navigation, they are compensated for by the service station itself. For this purpose, the part of the service station on which the mandrel and the couplings are mounted is installed on a linearly movable carriage.To ensure that the robot always finds the service station in the same condition, this movable carriage is held in the center position by springs.

[0027] Component tolerances are compensated for by floating couplings.

[0028] See also Fig. 3 The linear axis is shown at the top of the diagram. The ball-bearing sliding carriages run on this linear axis. The actual service station, with the couplings for water, electricity, and data, is mounted on the sliding carriages.

[0029] The angular misalignment can be compensated for using elastic buffer elements. These buffer elements must be positioned to compensate for the largest possible angle. One way to achieve this is by mounting four rubber buffers near the center. It is important to ensure that the rubber buffers yield sufficiently under the applied force to achieve the desired angle. The angle can be adjusted by changing the position of the rubber buffers as follows: Δ a = Elongation of the rubber elements b = Distance of the rubber elements to the center line F = Force applied c = Spring constant of the rubber element α = Angle Δ a = F c α = tan b Δ a

[0030] See also Fig. 4The base plate is shown at the top of this diagram. The base plate is firmly screwed to the room where the service station is operated. The movable plate is shown at the bottom of the image. The rubber elements are located between the base plate and the movable plate. As can be seen, the greater the distance b between the center line of the service station and the center line of the rubber elements, the larger the Δ must be. a to maintain the same angle of the movable plate relative to the base plate. So that Δ a If the force can increase while remaining constant, the spring constant of the rubber element must be reduced. However, reducing the spring constant simultaneously reduces stability against vertical forces. Therefore, it is essential to carefully match the position of the rubber elements to their specific properties.

[0031] Fresh water is pumped into the fresh water tank using mains pressure. To prevent leaks during water transfer, self-locking couplings are used. These couplings can compensate for a 1 mm misalignment caused by component tolerances. The fresh water supply is also stopped by a solenoid valve, allowing the coupling process to be carried out without pressure. This is important to keep the required coupling forces as low as possible. The solenoid valve is located in the service station's inlet line. It is purchased as a complete unit and features an aquastop function.

[0032] The regulations for the protection of drinking water from contamination according to DIN EN 1717 are complied with by installing a certified, double check valve in the fresh water supply line.

[0033] The wastewater is forced out of the robot by hypostatic pressure and collected by the service station. To ensure the wastewater can also be discharged into a higher-level drain, it is pumped out of the service station. The wastewater is transferred from the robot to the service station via a simple coupling. A section of pipe is attached to the front of the robot and connected to the robot's wastewater tank via a hose. To prevent the pipe from protruding from the robot's geometry and thus posing a potential hazard, the pipe section is mounted offset to the rear. The front end of the pipe section is therefore located behind the robot's leading edge. The counterpart is also a pipe section, attached to the service station. It is designed to be long enough to penetrate the robot's geometry during docking.A rubber seal is installed in the front part of the pipe section of the service station. This is intended to prevent the wastewater from leaking out unintentionally.

[0034] In Fig. 5 The pipe of the service station is shown on the left. The seal is located inside this pipe. The seal has internal fins, which are intended to provide a better seal compared to a smooth seal. The pipe section attached to the cleaning robot is shown on the right.

[0035] An alternative method for transferring wastewater is to transfer it via a basin located at the service station. When the cleaning robot is docked at the service station, the wastewater outlet is positioned above the basin. The wastewater that has flowed into the basin is then pumped out of the service station.

[0036] The charging current is transferred via charging contacts. To ensure uniform contact pressure and contact, the contacts are spring-mounted on one side.

[0037] This can - as in Fig. 6 shown - can be achieved through different possibilities. Contacts with externally mounted spring (1) Cylindrical contacts with built-in spring (2) Freely vibrating contacts made of spring steel (3)

[0038] In sub-representations 1) to 3) in Fig. 6 The fixed element to which the contacts are mounted is shown on the left. The surfaces in the images on the right represent the contact surfaces.

[0039] To prevent incorrect polarity of the charging contacts, the arrangement of the contacts is coded so that a connection is only possible in the correct position. See Fig. 7 .

[0040] Another option for transferring charging current is contactless charging of the batteries using induction or classic plug contacts, as is currently used, for example, in charging automotive electric vehicles.

[0041] The service station is controlled by the robot. This requires reliable data transmission between the robot and the service station. There are several ways to transmit data: mechanically, using the same principle as charging, or wirelessly via radio. The advantage of mechanical data transmission is that it also allows for verification of the cleaning robot's docking with the service station. If the robot can receive data from the service station, the docking must be successful.

[0042] A CAN bus is used as the data transmission protocol. This protocol requires two additional contacts for mechanical transmission.

[0043] Cleaning the squeegee lips can be achieved in various ways. State-of-the-art methods involve lifting the squeegee lip at specific intervals, resetting the cleaning machine, and then cleaning again. An improvement, however, is the active cleaning of the squeegee lip when the machine deliberately passes over a cleaning unit. This can be implemented as follows: The cleaning unit is integrated into the service station. The entire service station is positioned approximately 100 mm above the floor. This height difference can be overcome with a ramp. The elevation is necessary so that the cleaning unit for the squeegee lips can be recessed into the service station. The cleaning unit is positioned so that it must be passed over every time the machine approaches the service station. Thus, the lips are cleaned from both sides each time the machine approaches the service station.One side when driving forward to the service station and the other side when driving backward out of the service station.

[0044] In Fig. 9 The cleaning robot is shown docked at the service station. At the time shown, the cleaning robot has already passed over the suction lip cleaning unit. The cleaning unit for the suction lips is shown on the left of the image. The service station, to which the cleaning robot docks, is shown on the right.

[0045] Furthermore, it shows Fig. 9 , that the front wheel of the cleaning robot must overcome the recess for the brushes.

[0046] For this purpose, a linearly movable magazine is installed in the brush recess. This magazine also stores the brushes that the cleaning robot is intended to pick up automatically. The entire process is then as follows: The cleaning robot moves onto the service station. Its suction lip is cleaned during this process. Once the cleaning robot is docked at the service station, its batteries are charged and the water is replaced. At this point, the brush magazine is in the forward position. The magazine is then positioned so that an empty brush compartment is located beneath the robot. The cleaning robot then lowers its brushes, and these are removed. The magazine then moves into a position so that the desired brushes are located beneath the cleaning robot, and these are installed. Finally, the magazine moves back into the forward position.

[0047] In Fig. 10The service station is shown in a top view. The magazine is in the pass-through position. Therefore, the bridge required for the pass-through is in the center of the station. The replacement brushes are located in the various compartments within the magazine. One compartment is empty and can hold the brushes that are already installed on the robot.

[0048] An alternative to the movable brush magazine is for the robot to move itself to the various brush compartments. To do this, the robot drives onto the station to position 1. From this position, the robot can then dock with the service station to change the water and recharge the batteries. If the brushes need to be changed, the robot can swivel left or right using its drive wheels to access one or more brush compartments. The front wheel(s) are guided in a track embedded in the service station.

[0049] In Fig. 11The service station is shown in a top view. In the center are the compartments for the replacement brushes and an empty compartment for storing the brush mounted on the robot. A ramp between the compartments allows the robot to reach position 1 with its front wheel. The circular track guides the robot as it moves between the brush compartments. The right side of the image shows the part of the service station where the robot can dock for water changes and battery charging.

[0050] The brushes also represent other cleaning or floor preparation units, e.g. commercially available cleaning pads.

[0051] Different cleaning tasks may require the use of different cleaning agents. Therefore, the cleaning robot must be equipped with different cleaning agent containers. The automatic refilling of the cleaning agent can be implemented in the same way as the filling of the fresh water. For this purpose, one or more additional couplings are installed on both the cleaning robot and the service station. During the docking process, these couplings are then automatically connected. Reference symbol list

[0052] 1 Suction lip 2 Rear wheel 3 Front wheel 4 Cleaning robot 5 Brushes 6 Service station 7 Linear guide 8 Center line 9 Base plate 10 Movable plate 11 Edge of robot geometry 12 Tube at service station 13 Seal 14 Tube at robot 15 Contact surfaces 16 Position contacts 17 Ramp 18 Floor 19 Suction lip cleaning unit 20 Brush 21 Brush changing unit 22 Suction lip cleaning unit 23 Magazine 24 Replacement brushes 1 25 Drive-over ramp 26 Replacement brushes 2 27 Empty brush compartment 28 Suction lip cleaning unit 29 Replacement brushes 1 30 Replacement brushes 2 31 Drive-over ramp 32 Position 1 33 Service station 34 Empty compartment 35 Replacement brushes 3 36 lanes

Claims

1. A service station (6) for mobile robots (4) with a possibility for electrically charging the accumulators, wherein it comprises provisions for localization support, characterized in that provisions for compensating residual positioning inaccuracies are provided, wherein the existing residual deviation in the positioning between the service station and the mobile robot is compensated by means of a conical pin and a corresponding counterpart as a guide, wherein the pin has a clearance fit relative to the guide, wherein inaccuracies during the approach of the pin to the service station are compensated in that the part of the service station on which the pin and the couplings are mounted is mounted on a slide which is mounted linearly movably on the service station, and in that angular offset is compensable by elastic buffer elements.

2. The service station according to claim 1, characterized in that it comprises a transfer possibility for refilling fresh water or premixed cleaning liquid, and / or a possibility for draining and / or pumping out the dirty water, wherein the supply of fresh water is pumped into the fresh water tank by means of the line pressure from the building installation, and the dirty water is received by the service station and discharged into a drain into the wastewater line.

3. The service station according to claim 1 or 2, characterized in that it includes a device for automatically pumping out the dirty water from the mobile robot.

4. The service station according to claim 1, 2 or 3, characterized in that it comprises an additional transfer possibility for cleaning agent.

5. The service station according to one of the preceding claims, characterized in that it comprises a device for cleaning one or more squeegee lips.

6. A service station for mobile robots, characterized in that it comprises provisions for changing brushes and / or processing tools.