Mobile device for manipulating objects

Abstract

An apparatus for manipulating articles in which a multiaxial industrial robot is arranged on a travel unit and the industrial robot and the travel unit can be supplied with electrical energy via an energy storage unit. The travel unit has a control unit and at least three wheels having at least one drive unit, with the control unit being configured to rotate at least one of the wheels by the drive unit about an axis of rotation standing perpendicular on a symmetrical axis of rotation of the wheel and to rotate it about the symmetrical axis of rotation by the respective drive unit so that the apparatus can be moved in any direction by the travel unit. In addition, area monitoring sensors are arranged on at least two sides of the travel unit to monitor a virtual surface located at a predefined spacing next to and not intersecting the travel unit.

Claims

1. An apparatus for the manipulation of articles comprising a multi-axial industrial robot arranged on a travel unit, the industrial robot and the travel unit being supplied with electrical energy via an energy storage unit, the travel unit having a control unit and at least three wheels having at least one drive unit, the control unit being configured to use the drive unit to rotate at least one of the wheels about an axis of rotation standing perpendicular to a symmetrical axis of rotation of the wheel and to rotate the wheel about the symmetrical axis of rotation by the respective drive unit so that the apparatus is travelable wirelessly in any direction by the travel unit, wherein a respective area monitoring sensor is arranged on at least two sides of the travel unit, each of the area monitoring sensors being configured to monitor a virtual surface located at a predefined spacing next to the travel unit and not intersecting the travel unit with respect to an intrusion of at least one of persons and articles, and also with respect to checking a floor for at least one of irregularities and obstacles, and wherein an area monitored by the area monitoring sensors ends at the floor and is adjustable to be inclined by up to 10° with respect to the symmetrical axis of rotation of the wheel.

2. The apparatus in accordance with claim 1, wherein a respective drive unit for rotation about the axis of rotation and about the symmetrical axis of rotation is arranged at each of the wheels.

3. The apparatus in accordance with claim 1, wherein the drive unit has a first motor for rotating the wheel about the symmetrical axis of rotation of the wheel and has a second motor for rotating the wheel about the axis of rotation.

4. The apparatus in accordance with claim 3, wherein at least one of the first motor and the second motor is an electric motor.

5. The apparatus in accordance with claim 1, wherein the area monitoring sensors are formed as laser scanners.

6. The apparatus in accordance with claim 1, wherein an identification unit for identifying at least one of the apparatus and further articles present in the surroundings of the apparatus is arranged at the travel unit.

7. The apparatus in accordance with claim 6, wherein the identification unit is formed as an electromagnetic sensor.

8. The apparatus in accordance with claim 7, wherein the identification unit is configured to recognize reference marks in a non-contact manner.

9. The apparatus in accordance with claim 1, wherein at least two space monitoring sensors are arranged at the travel unit which monitor a surface disposed in parallel to the floor on which the travel unit moves for obstacles.

10. The apparatus in accordance with claim 1, wherein at least two floor monitoring sensors are arranged at the travel unit which monitor a floor on which the travel unit moves by monitoring a floor contour with respect to obstacles or holes.

11. The apparatus in accordance with claim 10, wherein the at least two floor monitoring sensors are formed as laser distance sensors.

12. The apparatus in accordance with claim 1, wherein protective rails having a contact sensor are arranged on at least two sides of the travel unit.

13. The apparatus in accordance with claim 1, wherein the energy storage unit is arranged in a hermetically sealed housing.

Description

(1) The invention will be explained in more detail by way of example in the following.

(2) There are shown:

(3) FIG. 1 a schematic side view of an apparatus with an industrial robot and a travel unit;

(4) FIG. 2 a perspective view of the travel nit with monitoring zones drawn in; and

(5) FIG. 3 a side view of the apparatus on a substrate picking from a device with a control unit drawn in.

(6) An apparatus is shown in a schematic side view in FIG. 1 in which an industrial robot 1 having six axes of rotation and thus six degrees of freedom is arranged on a travel unit 2. The industrial robot 1 is mounted on a frame 3 or on a housing. In further embodiments, the industrial robot 1 can also be arranged displaceably on the frame 3.

(7) The travel unit 2 is rectangular in a plan view and has four wheels 5 which have tires composed of a wear-resistant polyurethane in order also to be able to be used in clean rooms. An energy storage unit 4 in the form of an LFP battery enclosed in a hermetically sealed housing 27 is attached to the travel unit 2 between the wheels 5 or seated on the travel unit 2. The housing 27 of the energy storage unit 4 is composed of an electrically insulating material to avoid short-circuits and only has a passage for the electrical contacting of the energy storage unit with the further electrical and electronic parts of the apparatus. The housing 27 of the energy storage unit 4 is otherwise both airtight and gas-tight. A temperature sensor which monitors the temperature of the battery, a pressure sensor which monitors a pressure of the battery and an aerosol sensor which monitors an aerosol concentration with respect to aerosols discharged from the battery are additionally arranged in the housing 27. If a predefined threshold value of the temperature, of the pressure or of the aerosol concentration is reached, a signal is emitted to the control unit 23 and the apparatus is stopped and a warning signal is emitted.

(8) A control unit 23 in the form of a computer which controls at least one of the wheels 5, in the embodiment shown, however, all four wheels 5, is provided in the travel unit 2 or, as shown in FIG. 1, on the travel unit 2. For this purpose, an omni-drive module 6 is arranged at at least one of the wheels 5, in the embodiment shown an omni-drive module 6 is arranged at all four wheels 5, via which the wheels 5 can be rotated freely about an axis of rotation standing perpendicular on a symmetrical axis of rotation 7 to steer the travel unit 2 and via which said wheels can be driven so that they move the travel unit 2. For this purpose, the wheels 5 are rotated about the centrally supported symmetrical axis of rotation 7 on which the wheels 5 are rotatably supported.

(9) In further embodiments, the control unit 23 can also control an additional robot control unit which is likewise arranged on the travel unit 2 and which controls the industrial robot 1.

(10) The control unit 23 is also configured to control the industrial robot 1. Articles can be manipulated and moved in all six degrees of freedom by the industrial robot 1. The omni-drive module 6 or the omni-drive modules 6 have a first motor 24 for rotation about an axis of rotation and thus for steering as well as a second motor 25 for driving the wheels 5. Both motors 24, 25 are designed as electric motors which are supplied with electrical energy from the energy storage unit 4.

(11) The apparatus shown in FIG. 1 can be moved in a translatory manner in any desired directions on a floor by the travel unit 2 and can simultaneously also be rotated by a rotation of the wheels 5 about the axis of rotation standing perpendicular on the symmetrical axis of rotation 7. The travel unit 2 can thus cover straight distances in all directions at different speeds and can turn on the spot. Due to the free movability, the apparatus can travel to different process plants in the clean room, can there pick semiconductor substrates, which are also called wafers, or wafer cassette 15, boxes, individual masks or similar and transport them to a further process plant. The control unit 23 is directly programmed for this purpose, but a user can also reprogram the control unit 23 via an interface. For this purpose, a keypad and a display 18 are arranged at the frame 3 and/or an interface is provided for connecting these devices. In further embodiments, the control unit 23 has a transmission/reception unit by which the control unit 23 and thus the total apparatus can be controlled wirelessly by an external device, for example via radio.

(12) The wheels 5 are arranged at four corners of the travel unit 2 so that a respective two of the wheels are arranged aligned behind one another in a longitudinal direction and in a transverse direction. The omni-drive modules 6 are each mounted centrally above the wheels 5. A control effort to be managed by the control unit 23 is admittedly high due to an active drive and steering of the wheels 5 by the omni-drive modules 6 since the direction and the speed have to be determined for every travel state, but the travel unit 2 has a very high degree of agility, can turn on the spot and can maneuver in any direction. Independently of a preceding travel path, a positioning and repeat accuracy of Δx, Δy<±5 mm, Δz<±0.5 mm, ΔRx, ΔRy, ΔRz<±0.5° can be achieved and a handling accuracy can be achieved by the sensor system described in the following of Δx, Δy<±0.5 mm, Δz<±0.5 mm and ΔRx, ΔRy, ΔRz<±0.5°. A handling should in this respect be understood as an ability to handle objects in a firm state and a loading and unloading of process plants.

(13) A floor located in front of the apparatus can be monitored via four floor monitoring sensors 8 which are arranged at corners of the travel unit 2 in that a floor contour is checked by a distance measurement using a laser. Irregularities or obstacles on the floor can be recognized by the floor monitoring unit 8 which scans the floor as laser distance sensors in the monitoring zones 10 in a scan zone of at least 2 m. For this purpose, a laser beam is directed obliquely downwardly onto the floor from the floor monitoring sensors 8. The control unit 23 can stop the travel unit 2 in the case of detected obstacles or can evade the obstacles.

(14) The floor monitoring units 8 are arranged above the wheels 5 at a height of 180 mm above the floor in the embodiment shown in FIG. 1 and are arranged such that a floor part located obliquely directly in front of the wheels 5 is monitored. Holes in the floor and in the clean room, e.g. due to a removed floor plate which has not yet been reinserted, can hereby be recognized, for example, and a falling of the apparatus into such a hole is prevented.

(15) In addition, area monitoring sensors 11 are arranged at each corner of the housing and monitor the space surrounding the apparatus as laser scanners, the area monitoring sensors being arranged on a housing beneath which the control unit 23 and the travel unit 2 are arranged. Each of the space monitoring units 11 can also be attached above one of the wheels 5 and one of the floor monitoring units 8 or can be located centrally at one of the four sides of the housing. The four area monitoring sensors 11 can also be arranged in respective pairs aligned opposite one another at the four sides of the travel unit 2. The area monitoring sensors 11 generate a vertical “light curtain” 12 as a virtual area which is periodically swept over by a laser beam. The light curtain is in this respect not visible due to a use of a laser in the infrared or ultraviolet wavelength range; the laser can, however, also emit in the wavelength range between 400 nm and 700 nm, that is, in the visible range of the electromagnetic spectrum.

(16) Each of the virtual surfaces 12 is in this respect vertically aligned and extends next to the travel unit 2 such that the floor is also scanned and holes in the floor can also be detected by the area monitoring sensors. In further embodiments, these virtual surfaces 12 can also be inclined by up to 10° with respect to the vertical or to a normal of the floor, but never intersect the travel unit 2, but are rather always spaced apart from it. A closed light curtain is formed around a working zone of the industrial robot 1 by the virtual areas 12.

(17) If an interruption of the light curtain 12 is registered, for example by an intrusion of a person into a working zone of the industrial robot 1, the control unit 23 is configured to stop the industrial robot 1 and the travel unit 2 immediately and not to carry out any further movements or only to carry out movements at a reduced, safe speed. The apparatus additionally has a warning mechanism which is arranged at the travel unit 2 and which comprises in the embodiment shown a lamp and a loudspeaker by which optical and acoustic warning signals are emitted when one of the monitoring units 8 and 11 detects an irregularity. In further embodiments, however, only an optical warning device or only an acoustic warning device can also be provided.

(18) If the industrial robot is to grip from the light curtain, the control unit 23 can deactivate the corresponding area monitoring sensor 11 for a specific time.

(19) Protective rails 14 of plastic, for example of an elastomer, are moreover attached to the travel unit 2 at the level of the wheels and at least 2 cm above the floor at all four sides to protect the travel unit 2 from mechanical impairment on collisions. The protective rails 14 can also be arranged in further embodiments up to 10 cm above the floor to be able to travel up gradients without scraping. A respective one or more contact sensors are inserted in these rails 14 which transmit a signal to the control unit on contact so that the apparatus is stopped at this registered signal. Very flat articles lying on the floor can hereby be detected and the apparatus does not drive over them. The likewise drawn control unit 23 lies centrally on the travel unit 2.

(20) The industrial robot 1 in the embodiment shown in FIG. 1 has gripped a wafer cassette 15 via a gripper 22 and can in this respect exit the working space defined by the light curtain 12, for which purpose the control unit 23 can temporarily shut down the corresponding surface monitoring sensor 11.

(21) Space monitoring sensors 17, which monitor a virtual area 28 extending in parallel with the floor for obstacles, are now additionally arranged at the travel unit 2 at the corners above the wheels 5 and above the floor monitoring sensors. These sensors 17 are arranged at a height of 18 cm above the floor and should in every case detect a person lying on the floor.

(22) Two reception units 21 are arranged on the apparatus and can each receive two of the wafer cassettes 15 so that a total of four wafer cassettes 15 are transported. Due to an arrangement next to the industrial robot 1, the wafer cassettes 15 are only exposed to minimal acceleration values during a travel of the apparatus due to their slanted position; in addition, they lie ideally in the air flow of a room air-conditioning of the clean room.

(23) A perspective view of the industrial robot is shown with monitored virtual areas 12 in FIG. 2. Repeating elements are provided with identical reference numerals in this Figure and also in the following Figures. In this Figure, lateral monitoring zones of the apparatus are drawn as virtual areas 12 by which safety is ensured for users, machines and transported articles. The light curtain formed by these virtual areas 12 completely surrounds a working zone of the industrial robot 1 and is generated by the four area monitoring sensors 11. The light curtain can in this respect reach down to the floor, even though this is only the case in the embodiment shown in the two area monitoring sensors 11 mounted at the longitudinal axis of the apparatus.

(24) The apparatus is shown in a side view in front of a process plant 13 in FIG. 3. The apparatus moves in a clean room on a floor characterized by floor plates.

(25) The industrial robot 1 removes a wafer cassette 15 from the process plant 13 via the gripper 22, which is arranged at an end of the industrial robot 1 opposite the travel unit 2, in order to transport said wafer cassette to a further process plant. The control unit 23 for this purpose has positioned the apparatus via the travel unit 2 next to the process plant 13 at a spacing of 60 mm.

(26) A video camera 9 is arranged at the travel unit and reference marks, for example QR codes, can be recognized on the floor by it so that a more exact positioning of the apparatus is possible via these reference marks and via an evaluation of the recognized reference marks by the control unit 23. It is thus possible to navigate along fixed path points such as the QR codes or freely in the space between two points with a individual path selection.

(27) A video camera 9 arranged laterally at the apparatus and the control unit 23 check via a QR code 16 affixed to the floor next to the process plant 13 whether the apparatus is standing at the correct distance at the correct process plant 13. The QR code 16 is spaced apart from the process plant 13 by 80 mm for this purpose so that a safety distance is observed between the apparatus and the process plant 13. The QR code 16 is simultaneously arranged fixed in space with respect to the process plant 13.

(28) In addition, a charge-free contacting of the energy storage unit 4 is provided in which an electric current flow and/or an application of an electric voltage can only take place when a position of the travel unit 2 has been reliably determined. Induction coils are arranged in the floor for charging and an induction coil is likewise located in the hermetically sealed housing in which the energy storage unit 4 is arranged.

(29) To ensure a picking of wafer cassettes 15 only on a secure standing, the control unit 23 is configured to check whether the correct position was traveled to via the image recognition of the video camera 9. In addition, it is checked via an optical interface 19 at the travel unit 2 and its counter-piece 20 at the process plant 13 via an infrared signal that the correct position in front of the desired process plant 13 was actually adopted. Due to a restricted range of the optical interface 19 and 20 and a spatial restriction resulting from this, the plants cannot be confused. In further embodiments, another interface with a spatially restricted range, typically less than 15 cm, can also be used instead of an optical interface; for example, an electromagnetic sensor, in particular a radio frequency identification (RFID) sensor, can also be used for this purpose.

(30) In addition an odometric measurement for the spatial position determination is carried out via path sensors arranged at the wheels 5 or at the omni-drive modules 6. A safe signal which is defined by at least two independent channels according to different physical principles is generated from a combination of these three signals by the control unit 23.

(31) In addition, fail-safe, multi-channel transducers are arranged at two respective oppositely disposed wheels 5 which detect the direction of rotation and the speed of rotation and thus allow a determination of a secure standing of the total apparatus.

(32) Features of the different embodiment only disclosed in the embodiments can be combined with one another and claimed individually.