Patent Description:
<CIT> discloses a robotic vacuum (autonomous cleaning device) that collects or suctions dust, debris, etc. while traveling autonomously across a surface-to-be-cleaned. The robotic vacuum comprises an optical sensor (sensing module), which includes a rotating laser distance sensor (LDS) that detects surrounding objects for navigation, e.g., according to a simultaneous localization and mapping ("SLAM") algorithm.

The known optical sensor of <CIT> comprises: a base (rotary body), which rotates about a rotational axis during operation of the robotic vacuum; a light emitting unit provided on the rotatable base; a light receiving unit provided on the rotatable base; a protection cover disposed upward of the rotatable base; and support columns (legs) disposed around the rotatable base at intervals and supporting the protection cover. Detection light (e.g., infrared or visible light) emitted from the (rotating) light emitting unit passes through spaces between adjacent support columns and is radiated towards surrounding objects. Detection light reflected by one or more objects in the surrounding area passes (returns) through the spaces between adjacent support columns and enters (impinges upon) the light receiving unit. However, if the support columns are too thick in the design of <CIT>, then the passage of the detection (emitted) light and/or the reflected light may be so obstructed or blocked by the support columns that the detection accuracy of the optical sensor is reduced. On the other hand, if the support columns are made too thin (in order to avoid or minimize this detection accuracy reduction problem), then the strength of the support columns might become insufficient, thereby leading to the risk that the support columns will deform or break in case the protection cover contacts a surrounding object and/or a weight (pressure) is placed onto the protection cover from above and/or the side.

It is therefore one non-limiting object of the present invention to disclose one or more techniques for avoiding or reducing a decrease in detection accuracy of a rotating optical sensor of an autonomous cleaning device while ensuring sufficient strength (robustness) of legs (support columns) that support a cover for the rotating optical sensor.

The above object is solved by an autonomous cleaning device according to claim <NUM>. Further developments are recited in the dependent claims.

In one non-limiting aspect of the present teachings, an autonomous cleaning device includes an optical sensor that comprises: a rotary body adapted/configured to rotate about a rotational axis, e.g., relative to a substrate or base such as a support member or housing; a light-emitting device provided on the rotary body; a light-receiving device provided on the rotary body; a cover disposed upward of the rotary body; and legs (support columns) disposed at intervals around the rotary body and supporting the cover, e.g., relative to the substrate or base such as the support member or housing. In a cross section orthogonal to the rotational axis, at least a portion of a surface of each of the legs is inclined (slanted, sloped, oblique) with respect to a virtual radial line extending in a radial direction of the rotational axis. In other words, each of the legs may have at least one surface portion, preferably at least one flat surface portion, more preferably two discrete flat surface portions that form an angle with each other or are parallel to each other, that is (are) inclined or oblique with respect to a radial line that intersects and is perpendicular to the rotational axis, such that the surface portion forms an angle, other than a right angle, with the radial line.

In embodiments according to the above-mentioned aspect of the present teachings, it is possible to reduce or minimize a decrease in detection accuracy of the optical sensor of the autonomous cleaning device while providing robust legs for supporting the cover. Further objects, aspects, embodiments and advantages of the present invention will become apparent upon reading the following detailed description together with the appended drawings and claims.

As was mentioned in the preceding section, <FIG> show various views of a robotic vacuum (autonomous cleaning device) <NUM> according to a first exemplary, non-limiting embodiment of the present invention.

In the present embodiment and the further embodiments explained below, the positional relationships among the parts are explained using the terms "left," "right," "front," "rear," "up," and "down. " These terms indicate relative position or direction, using the center of the robotic vacuum <NUM> as a reference.

The robotic vacuum <NUM> collects dust, dirt, debris, etc. while traveling autonomously on a surface-to-be-cleaned FL. As shown in <FIG>, the robotic vacuum <NUM> comprises a main body <NUM>, a bumper <NUM>, two battery-mounting parts <NUM>, a fan unit <NUM>, a dust box <NUM>, two castors <NUM>, a roller <NUM>, a travelling apparatus <NUM>, a main brush <NUM>, a main-brush motor <NUM>, two side brushes <NUM>, two side-brush motors <NUM>, a handle <NUM>, a user interface (interface apparatus) <NUM>, obstacle sensors <NUM>, a cliff (drop-down prevention) sensor <NUM>, boundary (element) sensors <NUM>, an optical sensor <NUM>, and a controller <NUM>.

The main body <NUM> has an upper surface 2A; a bottom surface 2B, which opposes the surface-to-be-cleaned FL; and a side surface 2C, which connects a circumferential-edge part of the upper surface 2A and a circumferential-edge part of the bottom surface 2B. The outer shape of the main body <NUM> has a substantially circular shape within a plane that is parallel to the upper surface 2A.

The main body <NUM> comprises a housing <NUM>, which has an interior space. The housing <NUM> comprises: an upper housing 11A; a lower housing 11B, which is disposed downward of and is connected to the upper housing 11A; a cover plate 11C, which is mounted, such that it can be opened and closed, on the upper housing 11A; and a bottom plate 11D, which is mounted on the lower housing 11B. The upper surface 2A spans the upper housing 11A and the cover plate 11C. The bottom surface 2B spans the lower housing 11B and the bottom plate 11D.

The main body <NUM> has a suction port <NUM> provided in the bottom plate 11D. The suction port <NUM> is provided in (at) a front portion of the bottom surface 2B and opposes (faces) the surface-to-be-cleaned FL. The suction port <NUM> suctions in dust, debris, etc. from the surface-to-be-cleaned FL.

The bumper <NUM> opposes at least a portion of the side surface 2C and is movable relative to the side surface 2C. More specifically, the bumper <NUM> is supported in a movable manner by the main body <NUM> and opposes a front portion of the side surface 2C. When the bumper <NUM> bumps into an object in the vicinity of the robotic vacuum <NUM>, the bumper <NUM> moves relative to the main body <NUM> and thereby cushions the impact that acts on the main body <NUM>.

The two battery-mounting parts <NUM> respectively support two batteries (battery packs, battery cartridges) BT. That is, the batteries BT are respectively mounted on the battery-mounting parts <NUM>. Each battery-mounting part <NUM> is provided on at least a portion of an outer surface of the main body <NUM>, although it also possible to provide the battery-mounting part(s) such that it is (they are) disposed within the main body <NUM> and covered by a hinged cover. In the present embodiment, two recesses are provided on a rear portion of the upper housing 11A. The battery-mounting parts <NUM> are provided (defined) on inner sides of the recesses of the upper housing 11A.

When one or two of the batteries BT is (are) mounted on the battery-mounting parts <NUM>, the battery BT (or batteries BT) supplies (supply) electric power to the electrical components within the robotic vacuum <NUM>. The batteries BT are preferably general-purpose power tool batteries (battery packs, battery cartridges) that can be used as the power supply of various electrical components, such as other types of power tools (e.g., driver-drills, impact drivers, circular saws, etc.) and/or outdoor power equipment (e.g., blowers, mowers, string trimmers, etc.). The batteries BT also may be adapted/configured such that they can be used as the power supply of a vacuum (dust collector) other than the robotic vacuum <NUM> according to the present embodiment, such as an upright vacuum and/or a hand-held vacuum. The batteries BT may be lithium-ion batteries or another type of battery chemistry and are preferably rechargeable batteries. The battery-mounting parts <NUM> preferably each have a structure that is equivalent to the battery-mounting part of a power tool, so that power tool battery packs (cartridges) may be used with the robotic vacuum <NUM> in an interchangeable manner.

The fan unit <NUM> is disposed in the interior space of the housing <NUM>. The fan unit <NUM> generates a suction force, which is for suctioning dust, debris, etc., at (in) the suction port <NUM>. The fan unit <NUM> generates the suction force at (in) the suction port <NUM> via the dust box <NUM>. As shown in <FIG>, the fan unit <NUM> comprises: a casing 5A, which is disposed in the interior space of the housing <NUM>; a suction fan 5B, which is provided on an inner side of the casing 5A; and a suction motor 5C, which generates power that rotates the suction fan 5B. The casing 5A has: an air-suction port 5D, which is connected to the dust box <NUM>; and an air-exhaust port 5E.

The dust box <NUM> is disposed in the interior space of the housing <NUM>. The dust box <NUM> collects and stores the dust, debris, etc. that was suctioned in through the suction port <NUM>.

The cover plate 11C is mounted such that it is capable of opening and closing an opening provided in the upper housing 11A. A user of the robotic vacuum <NUM> can remove the dust box <NUM> from the interior space of the housing <NUM>, and can house (insert) the dust box <NUM> in the interior space of the housing <NUM>, through the opening in the upper housing 11A.

The two castors <NUM> and the roller <NUM> movably support the main body <NUM>. The castors <NUM> and the roller <NUM> are rotatably supported by the main body <NUM>. The two castors <NUM> are provided on a rear portion of the bottom surface 2B. One of the castors <NUM> is provided on a left portion of the main body <NUM>. The other castor <NUM> is provided on a right portion of the main body <NUM>. The single roller <NUM> is provided on the front portion of the bottom surface 2B.

The travelling apparatus <NUM> causes the main body <NUM> to move at least one of forward and rearward. The travelling apparatus <NUM> comprises two wheels <NUM> and two wheel motors <NUM>.

The wheels <NUM> movably support the main body <NUM>. The wheels <NUM> rotate about a rotational axis AX, which extends in the left-right direction. At least a portion of each wheel <NUM> protrudes downward beyond the bottom surface 2B. When the wheels <NUM> are placed on the surface-to-be-cleaned FL, the bottom surface 2B of the main body <NUM> opposes the surface-to-be-cleaned FL across a gap. One of the wheels <NUM> is provided on the left portion of the main body <NUM>. The other wheel <NUM> is provided on the right portion of the main body <NUM>.

The two wheel motors <NUM> generate power that respectively rotates the two wheels <NUM> using electric power supplied from the batteries BT. The wheel motors <NUM> are disposed in the interior space of the housing <NUM>. One of the wheel motors <NUM> generates power that rotates the wheel <NUM> provided on the left portion of the main body <NUM>. The other wheel motor <NUM> generates power that rotates the wheel <NUM> provided on the right portion of the main body <NUM>. The robotic vacuum <NUM> travels autonomously by rotating the wheels <NUM>.

The main brush <NUM> is disposed in the suction port <NUM> and opposes the surface-to-be-cleaned FL. The main brush <NUM> rotates about a rotational axis BX extending in the left-right direction. The main brush <NUM> comprises a rod 16R, which extends in the left-right direction, and a plurality of brushes 16B connected to an outer surface of the rod 16R. A left-end portion and a right-end portion of the rod 16R are each rotatably supported by the main body <NUM>. The rod 16R is supported by the main body <NUM> such that at least a portion of each brush 16B protrudes downward beyond the bottom surface 2B. When the wheels <NUM> are placed on the surface-to-be-cleaned FL, at least a portion of the main brush <NUM> contacts the surface-to-be-cleaned FL.

The main-brush motor <NUM> generates power that rotates the main brush <NUM> using electric power supplied from the batteries BT. The main-brush motor <NUM> is disposed in the interior space of the housing <NUM>. The main brush <NUM> is rotatably driven by the main-brush motor <NUM>. When the main brush <NUM> rotates, dust, debris, etc. present on the surface-to-be-cleaned FL is swept up and suctioned through the suction port <NUM>.

The two side brushes <NUM> are disposed on the front portion of the bottom surface 2B and oppose the surface-to-be-cleaned FL. At least a portion of each side brush <NUM> is disposed forward of the main body <NUM>. One of the side brushes <NUM> is provided leftward of the suction port <NUM>. The other side brush <NUM> is provided rightward of the suction port <NUM>. The side brushes <NUM> each comprise a plurality of brushes 18B connected to a disk 18D in a radially extending manner. The two disks 18D are rotatably supported by the main body <NUM> such that at least a portion of each corresponding brush 18B protrudes outward of the side surface 2C. When the wheels <NUM> are placed on the surface-to-be-cleaned FL, at least a portion of each side brush <NUM> contacts the surface-to-be-cleaned FL.

The two side-brush motors <NUM> generate power that respectively rotates the two side brushes <NUM> using electric power supplied from the batteries BT. The side-brush motors <NUM> are disposed in the interior space of the housing <NUM>. The side brushes <NUM> are rotatably driven by the side-brush motors <NUM>. Owing to the rotation of the side brushes <NUM>, dust, debris, etc. present around the main body <NUM> on the surface-to-be-cleaned FL is moved towards the suction port <NUM>.

The handle <NUM> is provided on a front portion of the upper housing 11A. First and second ends of the handle <NUM> are pivotably coupled to the upper housing 11A. The user of the robotic vacuum <NUM> can lift up the robotic vacuum <NUM> by holding the handle <NUM> and can thereby carry the robotic vacuum <NUM>.

The user interface <NUM> is disposed on a rear portion of the cover plate 11C. The user interface <NUM> comprises a plurality of manipulatable parts (e.g., press buttons or a touchscreen display), which are (is) manipulated (pressed) by the user of the robotic vacuum <NUM> to input manual commands, and one or more display parts. A power-supply button 30A is an illustrative example of a manipulatable part of the user interface <NUM>. Remaining-battery-charge display parts 30B of the batteries BT are illustrative examples of display parts of the user interface <NUM>.

The obstacle sensors <NUM> detect, in a non-contacting manner, objects present at least partly in the surroundings of the robotic vacuum <NUM>. Each obstacle sensor <NUM> comprises an ultrasonic sensor (ultrasonic sensor) that detects objects by emitting ultrasonic waves. More specifically, multiple obstacle sensors <NUM> are provided in a spaced apart manner on the side surface 2C of the main body <NUM>. Based on the detection data output by the obstacle sensors <NUM>, the controller <NUM> controls the wheel motors <NUM> so as to change the direction of advance of the travelling apparatus <NUM> or stop the travel of the travelling apparatus <NUM>, e.g., such that the main body <NUM> and the bumper <NUM> do not make contact with the object. It is noted that the controller <NUM> also may be adapted/configured to change the direction of advance or stop the travel of the travelling apparatus <NUM> after the main body <NUM> or the bumper <NUM> have made contact with an object.

The cliff sensor <NUM> detects, in a non-contacting manner, whether the surface-to-be-cleaned FL is located within a stipulated distance range from the bottom surface 2B. More specifically, the cliff sensor <NUM> comprises at least one optical sensor that detects objects (here, a floor) by emitting light and by processing light that is reflected from the object (floor). The cliff sensor <NUM> is disposed on the bottom surface 2B. As shown in <FIG>, the cliff sensor <NUM> may preferably comprise: a first cliff sensor 42F on the front portion of the bottom surface 2B; a second cliff sensor 42B provided on the rear portion of the bottom surface 2B; a third cliff sensor <NUM> provided on a left portion of the bottom surface 2B; and a fourth cliff sensor 42R provided on a right portion of the bottom surface 2B. The cliff sensor(s) <NUM> detect(s) the distance to the surface-to-be-cleaned FL by emitting detection light downward. If, based on the detection data output by the cliff sensor <NUM>, the controller <NUM> determines that the surface-to-be-cleaned FL is not present within the stipulated distance range from the bottom surface 2B, then the controller <NUM> controls the wheel motors <NUM> to stop the travel of the travelling apparatus <NUM> and/or change the direction of travel.

The boundary sensors <NUM> detect, in a non-contacting manner, demarcation elements provided on the surface-to-be-cleaned FL. Each boundary sensor <NUM> comprises an optical sensor that emits detection light to detect such demarcation elements. The boundary sensors <NUM> are disposed on the bottom surface 2B. As shown in <FIG>, multiple boundary sensors <NUM> are disposed in a spaced apart manner on the front portion of the bottom surface 2B. The user may dispose demarcation elements at any location(s) on the surface-to-be-cleaned FL that should serve as a boundary for cleaning work performed by the robotic vacuum <NUM>. For example, reflective tape that includes a reflective material is an illustrative example of a demarcation element according to the present teachings. The boundary sensors <NUM> detect the demarcation element(s) by emitting detection light downward. Based on the detection data output by the boundary sensors <NUM>, the controller <NUM> controls the wheel motors <NUM> so that the robotic vacuum <NUM> does not travel beyond (across) the demarcation element(s).

The optical sensor <NUM> emits detection light to detect, in a non-contacting manner, objects in the surroundings of the main body <NUM>. In the present embodiment, the optical sensor <NUM> comprises a laser sensor (light detection and ranging; LIDAR) that detects objects by emitting laser light, e.g. in the infrared wavelength range, in the visible wavelength range and/or in the ultraviolet wavelength range. Preferably, the optical sensor <NUM> may comprise a unit having an infrared-light emitter (e.g., an infrared laser diode) and an infrared-light sensor (e.g., a photodiode) that enables objects to be detected based upon detection of reflected infrared light or may comprise a radar sensor (radio detection and ranging; RADAR) that detects objects by emitting radio waves. The optical sensor <NUM> is disposed on the rear portion of the upper housing 11A in the present embodiment, but it may be disposed anywhere on the upper surface of the upper housing 11A so that electromagnetic radiation (e.g., light, radio waves, etc.) may be emitted <NUM>° around the robotic vacuum <NUM>.

<FIG> is an oblique view of a portion of the optical sensor <NUM> according to the present embodiment. <FIG> is an oblique view of another portion of the optical sensor <NUM> according to the present embodiment. <FIG> is a partial, broken oblique view of the optical sensor <NUM> according to the present embodiment. As shown in <FIG> and <FIG>, the optical sensor <NUM> comprises: a rotary body <NUM>, which rotates about a rotational axis CX; a light-emitting device <NUM>, which is provided on (affixed to) the rotary body <NUM>; a light-receiving device (light sensing device or light sensor) <NUM>, which is provided on (affixed to) the rotary body <NUM>; a cover <NUM>, which is disposed upward of the rotary body <NUM>; legs (support columns) <NUM>, which are disposed around the rotary body <NUM> and support the cover <NUM>; a support member <NUM>, which supports the legs <NUM>; and a coupling member <NUM>, which supports the support member <NUM> and/or enables the support member <NUM> to be coupled/connected to the main body <NUM>. Although the term "light" is utilized herein, it is understood that any embodiments that emit electromagnetic radiation are intended to be disclosed and covered by the term "light", regardless of whether the "light" (i.e. electromagnetic radiation) is in the visible (<NUM>-<NUM>) range or not.

As shown in <FIG>, the rotary body <NUM> comprises a top-plate part 51A, a side-plate part 51B, and a holding-plate part 51C. The interior space of the rotary body <NUM> is defined by the top-plate part 51A, the side-plate part 51B, and the holding-plate part 51C. The light-emitting device <NUM> and the light-receiving device <NUM> are disposed in the interior space of the rotary body <NUM>. The top-plate part 51A is disposed upward of the light-emitting device <NUM> and the light-receiving device <NUM>. The side-plate part 51B is disposed around the light-emitting device <NUM> and the light-receiving device <NUM>. The side-plate part 51B has a first opening 51D, through which the detection light emitted from the light-emitting device <NUM> passes, and a second opening 51E, through which the detection light that enters the light-receiving device <NUM> passes. The holding-plate part 51C is disposed downward of the top-plate part 51A and the side-plate part 51B. The light-emitting device <NUM> and the light-receiving device <NUM> are held by the holding-plate part 51C.

The rotary body <NUM> holds the light-emitting device <NUM> and the light-receiving device <NUM> such that rotation of the rotary body <NUM> causes the light-emitting device <NUM> and the light-receiving device <NUM> to also rotate therewith. Such rotation may be utilized, e.g., to perform simultaneous localization and mapping (SLAM) to generate navigation data for the robotic vacuum <NUM>. Rotational axis CX of the rotary body <NUM> is orthogonal to the upper surface 2A of the main body <NUM> and extends in the up-down (vertical) direction, i.e. perpendicular to the surface-to-be-cleaned FL. In a cross section orthogonal to rotational axis CX, the outer shape of the rotary body <NUM> is circular.

The cover <NUM> protects the rotary body <NUM> from above and the cover <NUM> is stationary relative to the main body <NUM>, such that the rotary body <NUM> rotates relative to the cover <NUM>. In a cross section orthogonal to rotational axis CX, the outer shape of the cover <NUM> is circular. The diameter of the cover <NUM> is larger than the diameter of the rotary body <NUM>.

The legs <NUM> are disposed (extend) downward of the cover <NUM>. The legs <NUM>, i.e. two, three or more of the legs <NUM>, are provided in a spaced apart manner around the rotary body <NUM>. In the present embodiment, four of the legs <NUM> are provided around the rotary body <NUM>.

The support member <NUM> is disposed downward of the legs <NUM>. At least a portion of the support member <NUM> is disposed around the rotary body <NUM>. In a cross section orthogonal to rotational axis CX, the outer shape of the support member <NUM> is circular. The diameter of the support member <NUM> is larger than the diameter of the rotary body <NUM>.

The coupling member <NUM> is disposed downward of the support member <NUM>. In the radial direction of rotational axis CX, at least a portion of the coupling member <NUM> protrudes outward of the outer surface of the support member <NUM>.

The coupling member <NUM> is coupled (attached) to the rear portion of the upper housing 11A. The coupling member <NUM> has openings 54A, in which bolts are respectively disposed. Therefore, the coupling member <NUM> and at least a portion of the upper housing 11A are fixed to one another by the bolts.

The cover <NUM>, the legs <NUM>, the support member <NUM>, and the coupling member <NUM> are one body, i.e. they are integrally formed without a seam therebetween, e.g., by a unitary polymer material. An upper-end part of each leg <NUM> is connected to the circumferential-edge part of the cover <NUM>. A lower-end part of each leg <NUM> is connected to the circumferential-edge part of the support member <NUM>. The cover <NUM>, the legs <NUM>, the support member <NUM>, and the coupling member <NUM> are each made of synthetic polymer (resin).

It is noted that the cover <NUM> and the legs <NUM> may be separate or discrete members that are joined together with a seam therebetween. The legs <NUM> and the support member <NUM> may be separate or discrete members that are joined together with a seam therebetween. The support member <NUM> and the coupling member <NUM> may be separate or discrete members that are joined together with a seam therebetween. In addition, the material of the cover <NUM> may differ from the material of the legs <NUM>. For example, the cover <NUM> may be made of synthetic polymer (resin), and the legs <NUM> may be made of metal, or vice versa.

It is noted that the support member <NUM> and the coupling member <NUM> may be omitted. In such an embodiment, the lower-end part of each leg <NUM> may be connected to the upper housing 11A and the rotary body <NUM> may be rotatably supported by a portion of the upper housing 11A.

<FIG> is a cross-sectional view of the rotary body <NUM> and the legs <NUM> according to the present (first) embodiment. <FIG> shows a cross section orthogonal to rotational axis CX. As shown in <FIG> and <FIG>, the light-emitting device <NUM> and the light-receiving device <NUM> are each provided on the rotary body <NUM>.

The light-emitting device <NUM> (e.g., one or more light-emitting diodes) emits detection light (electromagnetic radiation in any suitable wavelength(s)) for detecting objects. The light-emitting device <NUM> preferably emits laser light as the detection light. The light-emitting device <NUM> has a light-emitting surface <NUM>, from which the detection light is emitted. As the rotary body <NUM> rotates, the detection light emitted from the light-emitting surface <NUM> passes through spaces or openings, which are defined between (by) adjacent legs <NUM>, and is radiated towards objects in the surroundings of the main body <NUM>.

The light-receiving device (light sensor, e.g., one or more photodiodes) <NUM> receives at least a portion of the detection light emitted from the light-emitting device <NUM> that has been reflected by one or more objects in the surroundings of the main body <NUM>. The light-receiving device <NUM> has a light-receiving surface <NUM>, on which the detection light impinges. More specifically, at least a portion of the detection light, which is emitted from the light-emitting device <NUM> and is radiated towards an object, is reflected back to the light-receiving device <NUM> by that object. The detection light reflected by the object passes through one of the spaces between adjacent legs <NUM> and impinges on the light-receiving surface <NUM>. Based on the detection light received by the light-receiving device <NUM>, the controller <NUM> detects whether one or more objects is (are) present in the surroundings of the main body <NUM>. Based on the detection light received by the light-receiving device <NUM>, the light-receiving device <NUM> and/or the controller <NUM> may determine the distance(s) to the object(s).

The light-emitting surface <NUM> and the light-receiving surface <NUM> are each disposed upward of the upper surface 2A of the main body <NUM>. The detection light emitted, e.g., forward, from the light-emitting surface <NUM> passes through the spaces upward of the upper surface 2A of the main body <NUM> and is radiated towards objects, e.g., that are forward of the main body <NUM>. If the detection light is radiated towards an object forward of the main body <NUM>, then the detection light reflected by the object passes through the space upward of the upper surface 2A on the front side of the main body <NUM> and impinges on the light-receiving surface <NUM>. Therefore, the optical sensor <NUM> can detect objects that are, e.g., forward of the main body <NUM> without being hindered by the main body <NUM>.

As was described above, the light-emitting device <NUM> and the light-receiving device <NUM> are each fixed to the rotary body <NUM>. Therefore, when the rotary body <NUM> rotates about rotational axis CX, the light-emitting device <NUM> emits the detection light radially outwardly as it rotates <NUM>°. The light-receiving device <NUM> also receives the detection light while the rotary body <NUM> is rotating. Because the light-emitting device <NUM> emits detection light while the rotary body <NUM> is rotating, the detection light is radiated towards objects that surround the main body <NUM> in all directions. Based on the detection light received by the light-receiving device <NUM>, the controller <NUM> can detect objects in the surroundings of the main body <NUM>.

In the present embodiment, the rotary body <NUM> rotates in the rotational direction indicated by arrow RT in <FIG>. In the explanation below, the orientation (rotational direction) indicated by arrow RT (clockwise direction in <FIG>) is referred to as the "forward-rotation side" where appropriate, and the orientation (rotational direction) that is the reverse (counterclockwise direction in <FIG>) of the orientation indicated by arrow RT is referred to as the "reverse-rotation side" where appropriate.

<FIG> is a cross-sectional view that schematically shows the light-emitting device <NUM>, the light-receiving device <NUM>, and the legs <NUM> according to the present (first) embodiment in one rotational position of the (rotatable) rotary body <NUM> relative to the (stationary) legs <NUM>. As shown in <FIG>, the light-emitting surface <NUM> of the light-emitting device <NUM> and the light-receiving surface <NUM> of the light-receiving device <NUM> are disposed at different locations in the rotational direction of the rotary body <NUM>. In the present embodiment, the light-emitting surface <NUM> is disposed on the forward-rotation side of the light-receiving surface <NUM>. In addition, the light-emitting surface <NUM> is disposed on one side of rotational axis CX (in the example shown in <FIG>, on the right side of rotational axis CX), and the light-receiving surface <NUM> is disposed on the other side of rotational axis CX (in the example shown in <FIG>, on the left side of rotational axis CX).

In a cross section orthogonal to rotational axis CX, an optical axis Xa of an optical system of the light-emitting device <NUM> is inclined with respect to virtual (imaginary) radial lines RL (hereinafter, simply "virtual line RL") that extend radially outward emanating from rotational axis CX, i.e. radial lines that intersect rotational axis CX and are perpendicular thereto. (In <FIG>, although four virtual radial lines RL are shown by dot-dashed lines, the following description will refer to one (i.e. any one) of the virtual lines RL in the singular, because the various axes are inclined relative to any virtual radial line RL emanating from rotational axis CX. ) In a cross section orthogonal to rotational axis CX, an optical axis Xb of an optical system of the light-receiving device <NUM> also is inclined with respect to virtual line RL of rotational axis CX. It is noted that virtual line RL may also be defined as a (any) line that, in a cross section orthogonal to rotational axis CX, passes through (intersects) rotational axis CX and extends in the radial direction of rotational axis CX. Optical axis Xa and optical Xb are preferably not parallel, but rather are inclined relative to each other so that the optical axes Xa and Xb intersect in a direction forward (emission direction) of the light emitting surface <NUM>.

As described above, in the present embodiment, the light-emitting device <NUM> emits laser light as the detection light. The light beam of the detection light emitted from the light-emitting device <NUM> coincides with optical axis Xa of the light-emitting device <NUM>. At least a portion of the light beam of the detection light that enters the light-receiving device <NUM> coincides with optical axis Xb of the light-receiving device <NUM>.

In a cross section orthogonal to rotational axis CX, at least a portion of a surface of each leg <NUM> is inclined with respect to virtual line RL.

In the cross section orthogonal to rotational axis CX, the outer shape of each leg <NUM> is oblong, e.g., rectangular. In the cross section orthogonal to rotational axis CX, each leg <NUM> includes a first (flat) side surface <NUM>, a second (flat) side surface <NUM> parallel to the first side surface <NUM>, an inner surface <NUM>, and an outer surface <NUM>. The first side surface <NUM> and the second side surface <NUM> are each inclined (oblique) with respect to virtual line RL, in particular with regard to virtual lines RL that intersect the first side surface <NUM>.

The first side surface <NUM> faces a direction opposite the direction faced by the second side surface <NUM>, i.e. these surfaces are parallel. The inner surface <NUM> faces a direction opposite the direction faced by the outer surface <NUM>, i.e. these surfaces are parallel. In the present embodiment, the first side surface <NUM> faces the reverse-rotation side. The second side surface <NUM> faces the forward-rotation side. The inner surface <NUM> faces inward in the radial direction of rotational axis CX. The outer surface <NUM> faces outward in the radial direction of rotational axis CX. The distance between the first side surface <NUM> and the second side surface <NUM> is shorter than the distance between the inner surface <NUM> and the outer surface <NUM>.

The first side surface <NUM> has an inner-end part 71A on the innermost side of rotational axis CX in the radial direction and an outer-end part 71B on the outermost side of rotational axis CX in the radial direction. The first side surface <NUM> is inclined such that the inner-end part 71A is disposed on the forward-rotation side of the outer-end part 71B. The second side surface <NUM> has an inner-end part 72A on the innermost side of rotational axis CX in the radial direction and an outer-end part 72B on the outermost side of rotational axis CX in the radial direction. The second side surface <NUM> is inclined such that the inner-end part 72A is disposed on the forward-rotation side of the outer-end part 72B.

In the cross section orthogonal to rotational axis CX, an inclination angle θ of the first side surface <NUM> with respect to virtual line RL and the inclination angle θ of the second side surface <NUM> with respect to virtual line RL are <NUM>° or greater and <NUM>° or less, i.e. from <NUM>° to <NUM>°. This inclination angle θ emanates from a point (vertex) where one virtual radial line RL intersects the first side surface <NUM> or the second side surface <NUM> while the optical axis Xa coincides with the first side surface <NUM> or the second side surface <NUM>, respectively. In addition or in the alternative, this inclination angle θ emanates from a point (vertex) where one virtual radial line RL intersects a middle point of the first side surface <NUM> or the second side surface <NUM>, respectively, in the cross-section orthogonal to the rotational axis CX. In one exemplary example, this inclination angle θ may be <NUM>° or greater and <NUM>° or less, i.e. from <NUM>° to <NUM>°. In another exemplary example, this inclination angle θ may be <NUM>° or greater and <NUM>° or less, i.e. from <NUM>° to <NUM>°. It is noted that, the inclination angle θ also may be prescribed based on the inclination angle of optical axis Xa of the light-emitting device <NUM> with respect to a virtual line RL that intersects a middle point of the first surface <NUM> while the optical axis Xa coincides with the first surface <NUM>.

In the present embodiment, at least one of the first side surface <NUM> and the second side surface <NUM> are inclined such that it is (they are) parallel to, or coincide(s) with, optical axis Xa of the light-emitting device <NUM> when at least a portion of the leg <NUM> opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM>. In the example shown in <FIG>, the first side surface <NUM> coincides with optical axis Xa when the first side surface <NUM> and optical axis Xa overlap in a cross section orthogonal to rotational axis CX. It is noted that the second side surface <NUM> may coincide with optical axis Xa when the second side surface <NUM> and optical axis Xa overlap in the cross section orthogonal to rotational axis CX.

In the present embodiment, the shapes and the dimensions of all four of the legs <NUM> are identical. More specifically, the inclination directions and inclination angles θ of the legs <NUM> with respect to the four virtual lines RL depicted in <FIG> are identical.

According to the present embodiment, because the first side surface <NUM> and the second side surface <NUM> become parallel to, or coincide with, optical axis Xa of the light-emitting device <NUM> when at least a portion of the leg <NUM> opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM>, the leg <NUM> blocks less of the detection light, which is emitted from the light-emitting surface <NUM> than if the surfaces of the leg <NUM> are (as in the known art described above) arranged to be parallel or substantially parallel to the virtual radial lines RL. For example, even if the outer shape of the leg <NUM> is enlarged (widened) such that the distance between the first side surface <NUM> and the second side surface <NUM> becomes longer (wider), the time during which the detection light, which is emitted from the light-emitting surface <NUM> during rotation of the rotary body <NUM>, is blocked by the leg <NUM> does not become excessively long. Because a greater amount of the detection light emitted from the light-emitting surface <NUM> is radiated towards objects (i.e. less detection light is blocked by the legs <NUM>), the detection accuracy of the optical sensor <NUM> can be improved as compared to known optical sensors. In addition, by enlarging (widening) the outer shape of the leg <NUM> such that the distance between the first side surface <NUM> and the second side surface <NUM> becomes longer (wider), the legs <NUM> may be made more robust, thereby providing stronger support for the cover <NUM>.

<FIG> is a side view that schematically shows one of the castors <NUM> according to the present embodiment. <FIG> is an exploded oblique view of the castor <NUM> of <FIG>. The castor <NUM> shown in <FIG> and <FIG> is provided on the rear portion of the bottom surface 2B and is coupled to the lower housing 11B.

The castor <NUM> comprises: a rotary member <NUM>, which is rotatably coupled to the lower housing 11B; a wheel <NUM>, which is rotatably mounted on the rotary member <NUM> via a shaft <NUM>; and two pins <NUM>, which are mounted on the rotary member <NUM>.

The rotary member <NUM> rotates about a rotational axis DX, which extends in the up-down direction, i.e. vertical direction relative to the surface-to-be-cleaned FL. The lower housing 11B comprises a support shaft 11Bs, which rotatably supports the rotary member <NUM>. The support shaft 11Bs protrudes downward from the bottom surface 2B of the main body <NUM>. The rotary member <NUM> has a hole 81A, into which the support shaft 11Bs is inserted. The hole 81A is provided in an upper surface of the rotary member <NUM>. When the support shaft 11Bs is disposed in the hole 81A, the rotary member <NUM> is rotatable about rotational axis DX.

As shown in <FIG>, a recessed part <NUM> is provided in a portion of the rotary member <NUM>. The rotary member <NUM> has holes 81B provided on both sides of the recessed part <NUM>.

The wheel <NUM> has a hole 83A, into which the shaft <NUM> is inserted. The wheel <NUM> is disposed in the recessed part <NUM>. When the wheel <NUM> is disposed in the recessed part <NUM>, the shaft <NUM> is inserted into the holes 81B of the rotary member <NUM> and the hole 83A of the wheel <NUM>. When the shaft <NUM> is disposed in the holes 81B of the rotary member <NUM> and the hole 83A of the wheel <NUM>, a tip part of the shaft <NUM> and the wheel <NUM> are fixed by a stop ring <NUM>.

The two pins <NUM> are respectively inserted in two holes 81C, which are provided in the upper surface of the rotary member <NUM>. The holes 81C are provided outward of the hole 81A in the radial direction of rotational axis DX. The pins <NUM> are inserted into the holes 81C such that upper-end parts of the pins <NUM> protrude upward of the upper surface of the rotary member <NUM>.

The hardness of the pins <NUM> is greater than the hardness of the rotary member <NUM>. Therefore, the pins <NUM> tend to wear less than the rotary member <NUM>. In the present embodiment, the pins <NUM> are made of metal. The rotary member <NUM> is made of synthetic polymer (resin).

When the pins <NUM> are inserted into the holes 81C, the upper-end parts of the pins <NUM> make contact with the bottom surface 2B. In the present embodiment, the upper-end parts of the pins <NUM> are disposed upward of the upper surface of the rotary member <NUM>. Consequently, contact between the upper surface of the rotary member <NUM> and the bottom surface 2B is prevented.

The rotary member <NUM> is rotatable while the upper-end parts of the pins <NUM> contact the bottom surface 2B. Therefore, when the rotary member <NUM> rotates, the upper surface of the rotary member <NUM> and the bottom surface 2B do not rub against one another. Consequently, wear of the rotary member <NUM> is prevented. As was noted above, because the pins <NUM> are made of metal, they tend to wear less than the rotary member <NUM>. Consequently, even though the rotary member <NUM> rotates, deterioration of the pins <NUM> is prevented or at least minimized.

It is noted that, when the pins <NUM> are inserted into the holes 81C, the upper-end parts of the pins <NUM> and the upper surface of the rotary member <NUM> may be disposed at the same height. In addition, when the upper-end parts of the pins <NUM> contact the bottom surface 2B, the upper surface of the rotary member <NUM> may contact the bottom surface 2B.

<FIG> is a cross-sectional view of one of the side brushes <NUM> according to the present embodiment. As was explained above, each side brush <NUM> of the present embodiment comprises the brushes 18B connected to the disk 18D in a radially extending manner. The disk 18D is disposed in the lower housing 11B and rotates about a rotational axis EX, which extends in the up-down direction.

A lower surface of the disk 18D opposes the surface-to-be-cleaned FL. The lower surface of the disk 18D includes a curved surface. Therefore, the lower surface of the disk 18D is inclined outward in the radial direction of rotational axis EX and upward. In a cross section parallel to rotational axis EX, the lower surface of the disk 18D has an arcuate shape that protrudes downward. In the present embodiment, the lower surface of the disk 18D has a semispherical shape.

Because the lower surface of the disk 18D includes a curved surface, even if the lower surface of the disk 18D contacts the surface-to-be-cleaned FL, obstruction of the rotation of the disk 18D is minimal, thereby minimizing or avoiding damage to the surface-to-be-cleaned FL. For example, if the surface-to-be-cleaned FL is a carpet surface, then the disk 18D tends not to embed in the carpet. In addition, even if the lower surface of the disk 18D contacts the carpet surface, there is little or no increase in the rotational resistance of the disk 18D. In addition, even if the lower surface of the disk 18D contacts the surface-to-be-cleaned FL while the robotic vacuum <NUM> is travelling across the surface-to-be-cleaned FL owing to the driving of the travelling apparatus <NUM>, the disk 18D tends not to get stuck in or on the surface-to-be-cleaned FL. Consequently, the robotic vacuum <NUM> can smoothly travel across the surface-to-be-cleaned FL owing to the curved shape of the disk 18D.

As shown in <FIG>, the robotic vacuum <NUM> comprises: a rotary shaft <NUM>, which is disposed in the interior space of the housing <NUM>; a bearing <NUM>, which rotatably supports the rotary shaft <NUM>; a gear part <NUM>, which is connected to the rotary shaft <NUM>; and a gear housing <NUM>, which is disposed around the gear part <NUM> in the interior space of the housing <NUM>. The gear housing <NUM> supports the bearing <NUM>.

The power generated by the side-brush motor <NUM> is transmitted to the rotary shaft <NUM> via the gear part <NUM>. The rotary shaft <NUM> rotates about rotational axis EX owing to the rotational drive of the side-brush motor <NUM>.

The disk 18D is coupled or fixed to the lower-end part of the rotary shaft <NUM> by a screw <NUM>. Owing to the rotation of the rotary shaft <NUM>, the side brush <NUM> rotates about rotational axis EX.

Each disk 18D comprises: an inner-tube part (boss) <NUM>, into which the lower-end part of the rotary shaft <NUM> is inserted; a first outer-tube part (boss) <NUM>, which is disposed around the inner-tube part <NUM>; and a second outer-tube part (boss) <NUM>, which is disposed around the first outer-tube part <NUM>.

The height of an upper-end surface of the inner-tube part <NUM> is the same as the height of an upper-end surface of the first outer-tube part <NUM>. It is noted that the upper-end surface of the first outer-tube part <NUM> may be disposed at a location higher than the upper-end surface of the inner-tube part <NUM>. The upper-end surface of the second outer-tube part <NUM> may be disposed at a location that is lower than the upper-end surface of the inner-tube part <NUM> and the upper-end surface of the first outer-tube part <NUM>.

A portion of the gear housing <NUM> is disposed in the space between the inner-tube part <NUM> and the first outer-tube part <NUM>. The gear housing <NUM> does not (directly) contact the disk 18D. A portion of the gear housing <NUM> opposes (faces) an outer-circumference surface of the inner-tube part <NUM> across a minute gap. A portion of the gear housing <NUM> opposes (faces) the upper-end surface of the first outer-tube part <NUM> across a minute gap. A first labyrinth seal is formed between the inner-tube part <NUM> and the first outer-tube part <NUM> on one side and the gear housing <NUM> on the other side.

A portion of the lower housing 11B is disposed in the space between the first outer-tube part <NUM> and the second outer-tube part <NUM>. The lower housing 11B does not contact the disks 18D. A portion of the lower housing 11B opposes (faces) the outer-circumference surface of the first outer-tube part <NUM> across a minute gap. A portion of the lower housing 11B opposes (faces) the upper-end surface of the second outer-tube part <NUM> across a minute gap. A second labyrinth seal is formed between the first outer-tube part <NUM> and the second outer-tube part <NUM> on one side and the lower housing 11B on the other side.

The formation of the labyrinth seals hinders or obstructs the ingress of foreign matter into the space around the rotary shaft <NUM>. If hair-like foreign matter, such as hair and threads, present on the surface-to-be-cleaned FL contacts the rotary shaft <NUM>, then there is a possibility that rotation of the rotary shaft <NUM> will be hindered. In the present embodiment, the labyrinth seals are formed around the rotary shaft <NUM>. Consequently, hair-like foreign matter is hindered from penetrating into the space around the rotary shaft <NUM>.

According to the first embodiment as explained above, in a cross section orthogonal to rotational axis CX of the rotary body <NUM>, at least a portion of the surface (preferably, a flat surface) of the leg <NUM> is inclined (oblique, slanted) with respect to virtual line RL emanating from rotational axis CX. Consequently, even if the cross-sectional area of the leg <NUM> is enlarged (e.g., widened), the time during which the detection light, which is emitted from the light-emitting surface <NUM> while the rotary body <NUM> is rotating, is blocked by the leg <NUM> does not become excessively long. By reducing the amount of the detection light that is blocked by each of the legs <NUM>, improved detection accuracy of the optical sensor <NUM> is made possible. In addition, by the enlarging of the cross-sectional area of each of the legs <NUM>, the legs <NUM> can be made more robust with minimal effect on (reduction of) the detection accuracy.

In the present embodiment, when at least a portion of the leg <NUM> opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM>, the corresponding first side surface <NUM> and the corresponding second side surface <NUM> are each parallel to, or coincide with, optical axis Xa of the light-emitting device <NUM>. Consequently, for example, even if the outer shape of the leg <NUM> is enlarged (widened) such that the distance between the first side surface <NUM> and the second side surface <NUM> becomes longer (wider), the time during which the detection light, which is emitted from the light-emitting surface <NUM> during rotation of the rotary body <NUM>, is blocked by the leg <NUM> does not become excessively long. Thus, as was explained above, by reducing the amount of the detection light that is blocked by each of the legs <NUM>, improved detection accuracy of the optical sensor <NUM> is made possible. Moreover, by the enlarging of the cross-sectional area of each of the legs <NUM>, the legs <NUM> can be made more robust with minimal effect on (reduction of) the detection accuracy.

It is noted that, in a modification of the first embodiment described above, the inclination angles θ of the legs <NUM>, with respect to a virtual line RL that intersects a middle point of the respective leg <NUM>, may differ from one another. For example, the inclination angle θ of a first leg <NUM> may be <NUM>°, and the inclination angle θ of a second leg <NUM> may be <NUM>°, in accordance with the definitions provided above.

In addition or in the alternative, in the first embodiment described above, four of the legs <NUM> are provided. However, in the alternative, two or three of the legs <NUM> or five or more of the legs <NUM> may be provided around the rotary body <NUM>.

In addition or in the alternative, in another modification of the first embodiment described above, the first side surface <NUM> and the second side surface <NUM> do not have to be parallel to one another, as will be demonstrated in additional embodiments described below.

A second embodiment will now be explained. In the explanation below, structural elements the same as or equivalent to those in the embodiment described above are assigned the same symbols, and explanations thereof are abbreviated or omitted.

<FIG> is a cross-sectional view that schematically shows the light-emitting device <NUM>, the light-receiving device <NUM>, and the legs <NUM> according to the present (second) embodiment. The same as in the embodiment described above, in a cross section orthogonal to rotational axis CX, each leg <NUM> includes the first (flat) side surface <NUM>, the second (flat) side surface <NUM> parallel to the first side surface <NUM>, the inner surface <NUM>, and the outer surface <NUM>. The first side surface <NUM> and the second side surface <NUM> are each inclined (oblique) with respect to virtual line RL (i.e. with respect to a virtual line RL that intersects the first side surface <NUM> or the second side surface <NUM>).

In the present (second) embodiment, the first side surface <NUM> is inclined such that the inner-end part 71A is disposed on the reverse-rotation side of the outer-end part 71B. The second side surface <NUM> is inclined such that the inner-end part 72A is disposed on the reverse-rotation side of the outer-end part 72B.

In a cross section orthogonal to rotational axis CX, an inclination angle θ of the first side surface <NUM> with respect to virtual line RL and the inclination angle θ of the second side surface <NUM> with respect to virtual line RL are <NUM>° or greater and <NUM>° or less, i.e. from <NUM>° to <NUM>°. This inclination angle θ emanates from a point (vertex) where one virtual radial line RL intersects the first side surface <NUM> or the second side surface <NUM> while the optical axis Xb coincides with the first side surface <NUM> or the second side surface <NUM>. In addition or in the alternative, this inclination angle θ emanates from a point (vertex) where one virtual radial line RL intersects a middle point of the first side surface <NUM> or the second side surface <NUM>, respectively, in the cross-section orthogonal to the rotational axis CX. In one exemplary example, this inclination angle θ may be <NUM>° or greater and <NUM>° or less, i.e. from <NUM>° to <NUM>°. In another exemplary example, this inclination angle θ may be <NUM>° or greater and <NUM>° or less, i.e. from <NUM>° to <NUM>°. It is noted that, the inclination angle θ may be prescribed based on the inclination angle of optical axis Xb of the light-receiving device <NUM> with respect to a virtual line RL that intersects a middle point of the second side surface <NUM> while the optical axis Xb coincides with the second side surface <NUM>.

In the present embodiment, at least one of the first side surface <NUM> and the second side surface <NUM> is inclined (oblique, slanted) such that it is parallel to, or coincides with, optical axis Xb of the light-receiving device <NUM> when at least a portion of the leg <NUM> opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>. In the example shown in <FIG>, when the second side surface <NUM> and optical axis Xb overlap in a cross section orthogonal to rotational axis CX, the second side surface <NUM> and optical axis Xb are parallel or coincide. It is noted that, when the first side surface <NUM> and optical axis Xb overlap in a cross section orthogonal to rotational axis CX, the first side surface <NUM> and optical axis Xb may be parallel or may coincide.

In the present embodiment, the shapes and the dimensions of the legs <NUM> are identical. More specifically, the inclination directions and inclination angles θ of the legs <NUM> with respect to the four virtual lines RL depicted in <FIG> are identical.

According to the second embodiment as explained above, when at least a portion of the leg <NUM> opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>, because the first side surface <NUM> and the second side surface <NUM> are parallel to, or coincide with, optical axis Xb of the light-receiving device <NUM>, less of the detection light, which is reflected by the object, is blocked by the leg <NUM>. For example, even if the outer shape of each of the legs <NUM> is enlarged (widened) such that the distance between the first side surface <NUM> and the second side surface <NUM> becomes longer (wider), the time during which the detection light, which was reflected by the object during rotation of the rotary body <NUM>, is blocked by the leg <NUM> does not become excessively long. Because more of the detection light reflected by the object impinges on the light-receiving surface <NUM> (i.e. less light is blocked by the legs <NUM>), the detection accuracy of the optical sensor <NUM> can be improved as compared to known designs while also making the legs <NUM> more robust.

It is noted that, in a modification of the second embodiment described above as well, the inclination angles θ of the legs <NUM>, with respect to a virtual line RL that intersects a middle point of the respective leg <NUM>, may differ from one another. For example, the inclination angle θ of a first leg <NUM> may be <NUM>°, and the inclination angle θ of a second leg <NUM> may be <NUM>°, in accordance with the definitions provided above.

In addition or in the alternative, in the second embodiment described above, although four of the legs <NUM> are provided, two or three of the legs <NUM> or five or more of the legs <NUM> may instead be provided around the rotary body <NUM>.

In addition or in the alternative, in another modification of the second embodiment described above as well, the first side surface <NUM> and the second side surface <NUM> do not have to be parallel to one another.

A third embodiment will now be explained. In the explanation below, structural elements the same as or equivalent to those in the embodiment described above are assigned the same symbols, and explanations thereof are abbreviated or omitted.

<FIG> is a cross-sectional view that schematically shows the light-emitting device <NUM>, the light-receiving device <NUM>, and the legs <NUM> according to the present (third) embodiment. As shown in <FIG>, the legs <NUM> include first legs 70A and second legs 70B, whose inclination directions differ. In the example shown in <FIG>, the first legs 70A and the second legs 70B are disposed in an alternating manner around rotational axis CX.

The first (preferably flat) side surface <NUM> of each first leg 70A is inclined (oblique) such that the corresponding inner-end part 71A is disposed on the forward-rotation side of the corresponding outer-end part 71B. The second (preferably flat) side surface <NUM> of each first leg 70A is inclined (oblique) such that the corresponding inner-end part 72A is disposed on the forward-rotation side of the corresponding outer-end part 72B.

The first side surface <NUM> of the second leg 70B is inclined such that the inner-end part 71A is disposed on the reverse-rotation side of the outer-end part 71B. The second side surface <NUM> of the second leg 70B is inclined such that the inner-end part 72A is disposed on the reverse-rotation side of the outer-end part 72B.

When at least a portion of the first leg 70A opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM>, at least one of the first side surface <NUM> and the second side surface <NUM> of that first leg 70A is inclined such that it is parallel to, or coincides with, optical axis Xa of the light-emitting device <NUM>.

At least one of the first side surface <NUM> and the second side surface <NUM> of the second leg 70B is inclined such that it is parallel to, or coincides with, optical axis Xb of the light-receiving device <NUM> when at least a portion of the second leg 70B opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>.

As explained above, the inclination directions of the legs <NUM> with respect to a virtual line RL that intersects the respective leg <NUM> may differ from one another. In the present embodiment, too, a decrease in detection accuracy can be curtailed while increasing the strength of the legs <NUM>. More specifically, the two legs 70A permit a greater amount of detection light to pass (owing to having a cross-section that blocks less light from light-emitting device <NUM>), whereas the two legs 70B permit a greater amount of reflected light to pass (owing to having a cross-section that blocks less reflected light from reaching the light-receiving device <NUM>). Therefore, by generating mapping data using all data that is collected, overall detection accuracy can be improved.

A fourth embodiment will now be explained. In the explanation below, structural elements the same as or equivalent to those in the embodiment described above are assigned the same symbols, and explanations thereof are abbreviated or omitted.

<FIG> is a cross-sectional view that schematically shows the light-emitting device <NUM>, the light-receiving device <NUM>, and the legs <NUM> according to the present (fourth) embodiment. As shown in <FIG>, the legs <NUM> comprise the first leg 70A, the second leg 70B, and third legs 70C. The inclination direction of the first leg 70A and the inclination direction of the second leg 70B are respectively the same as the inclination direction of the first leg 70A and the inclination direction of the second leg 70B explained in the third embodiment described above. The first side surface <NUM> and the second side surface <NUM> of each third leg 70C is parallel to a virtual line RL that intersects the middle of the respective leg 70C.

As explained above, two of the legs 70A, 70B (from among the plurality of legs <NUM>) are inclined (oblique) with respect to a virtual line RL that intersects it, whereas two of the legs 70C are not inclined with respect to a virtual line RL that intersects a middle of the respective leg 70C. In the present embodiment, too, a decrease in detection accuracy can be curtailed while increasing the strength of the legs <NUM>.

A fifth embodiment will now be explained. In the explanation below, structural elements the same as or equivalent to those in the embodiment described above are assigned the same symbols, and explanations thereof are abbreviated or omitted.

<FIG> and <FIG> are each a cross-sectional view that schematically shows the light-emitting device <NUM>, the light-receiving device <NUM>, and the legs <NUM> according to the present embodiment. <FIG> is a cross-sectional view that schematically shows one of the legs <NUM> according to the present embodiment in greater detail. <FIG> shows the state in which, owing to the rotation of the rotary body <NUM>, one of the legs <NUM> (i.e. the lower, left leg <NUM>) opposes (faces) the light-emitting surface <NUM>. <FIG> shows the state in which, owing to the rotation of the rotary body <NUM>, one of the legs <NUM> (i.e. the lower, right leg <NUM>) opposes (faces) the light-receiving surface <NUM>.

In the present fifth embodiment, each leg <NUM> includes an inner-end area <NUM> having an inner-end part <NUM> in the radial direction of rotational axis CX. The inner-end area <NUM> has two inclined (flat) surfaces (75A, 75B) with respect to a virtual line RL that intersects the inner-end part <NUM>. That is, the two flat, inclined surfaces (75A, 75B) of the inner-end area <NUM> and the virtual line RL intersect at the inner-end part <NUM>, which is an apex or vertex of the two inclined surfaces (75A, 75B).

More specifically, as shown in <FIG> and <FIG>, the inner-end area <NUM> includes a first inner-end area (flat surface) 75A, which is inclined relative to the virtual line RL such that the first inner-end area (flat surface) 75A is parallel to, or coincides with, optical axis Xa of the light-emitting device <NUM> when at least a portion of the leg <NUM> opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM>. In other words, there is one rotational position of the light-emitting device <NUM> relative to the leg <NUM> where optical axis Xa (which is a straight line) coincides (intersects at infinitely many points) with the first inner-end area (flat surface) 75A. In addition, as shown in <FIG> and <FIG>, the inner-end area <NUM> includes a second inner-end area 75B, which is inclined relative to the virtual line RL such that it is parallel to, or coincides with, optical axis Xb of the light-receiving device <NUM> when at least a portion of the leg <NUM> opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>. In other words, there is one rotational position of the light-receiving device <NUM> relative to the (same) leg <NUM> where optical axis Xb (which is a straight line) coincides (intersects at infinitely many points) with the second inner-end area (flat surface) 75B. Consequently, in the present fifth embodiment, the first inner-end <NUM> of each of the legs <NUM> has the shape of an isosceles triangle in plan view, whereby the virtual line RL that intersects the inner-end part <NUM> serves as an axis of symmetry for the first inner-end <NUM> in plan view.

In addition, each leg <NUM> includes an outer-end area <NUM> having an outer-end part 70T in the radial direction of rotational axis CX.

The outer-end area <NUM> includes: a first outer-end area (surface) 76A, which is connected to the first inner-end area 75A and is partially inclined, in the opposite direction to that of the first inner-end area 75A, with respect to the virtual line RL that intersects the inner-end part <NUM> and is partially parallel to that virtual line RL; and a second outer-end area (surface) 76B, which is connected to the second inner-end area 75B and is partially inclined, in the opposite direction to that of the second inner-end area 75B, with respect to the virtual line RL that intersects the inner-end part <NUM> and is partially parallel to that virtual line RL.

The first inner-end area 75A and the first outer-end area 76A each face the reverse-rotation side. The second inner-end area 75B and the second outer-end area 76B each face the forward-rotation side.

An inner-end part 75Sa of the first inner-end area 75A includes the inner-end part <NUM> of the leg <NUM>. An outer-end part 75Ta of the first inner-end area 75A is connected to an inner-end part 76Sa of the first outer-end area 76A. An outer-end part 76Ta of the first outer-end area 76A includes the outer-end part 70T of the leg <NUM>. The inner-end part 75Sa of the first inner-end area 75A is disposed on the forward-rotation side of the outer-end part 75Ta of the first inner-end area 75A. The inner-end part 76Sa of the first outer-end area 76A is disposed on the reverse-rotation side of the outer-end part 76Ta of the first outer-end area 76A.

An inner-end part 75Sb of the second inner-end area 75B includes the inner-end part <NUM> of the leg <NUM>. An outer-end part 75Tb of the second inner-end area 75B is connected to an inner-end part 76Sb of the second outer-end area 76B. An outer-end part 76Tb of the second outer-end area 76B includes the outer-end part 70T of the leg <NUM>. The inner-end part 75Sb of the second inner-end area 75B is disposed on the reverse-rotation side of the outer-end part 75Tb of the second inner-end area 75B. The inner-end part 76Sb of the second outer-end area 76B is disposed on the forward-rotation side of the outer-end part 76Tb of the second outer-end area 76B.

In the cross section orthogonal to rotational axis CX, the inner-end area <NUM> has an angled shape, i.e. the isosceles triangle shape mentioned above. On the other hand, in the cross section orthogonal to rotational axis CX, the outer-end area <NUM> may include a curvilinear shape, although the shape of the outer-end area <NUM> is not particularly limited, as long as, e.g., the outer-end area <NUM> does not block optical axis Xa when optical axis Xa coincides with first inner-end area (surface) 75A or optical axis Xb when optical axis Xb coincides with second inner-end area (surface) 75B. In other words, the outer-end area <NUM> may preferably be made as wide or even wider than the widest portion of inner-end area <NUM> in plan view, in order to impart additional strength (robustness) to the leg <NUM>. Therefore, the inner-end area <NUM> is designed to provide minimal blocking of the optical axes Xa and Xb when the optical axes Xa and Xb respectively rotate past the leg <NUM>, whereas the outer-end area <NUM> is made wider or thicker in order to increase the overall strength of the leg <NUM> so that it robustly supports the cover <NUM>.

In the present fifth embodiment as explained above, in the cross section orthogonal to rotational axis CX of the rotary body <NUM>, at least a portion of the surface of the leg <NUM> is inclined (oblique) with respect to a virtual line RL of rotational axis CX that intersects the respective leg <NUM>. Consequently, even if the overall cross-sectional area of the leg <NUM> is enlarged (widened), in particular in the outer-end area <NUM>, the time during which the detection light, which is emitted from the light-emitting surface <NUM> while the rotary body <NUM> is rotating, is blocked by the leg <NUM> does not become excessively long. Because the blocking of the detection light by the legs <NUM> is curtailed (reduced or minimized), any decrease in the detection accuracy of the optical sensor <NUM> is curtailed. In addition, by the enlarging of the overall cross-sectional area of each of the legs <NUM>, the strength of the legs <NUM> can be increased to provide more robust support for the cover <NUM>.

In the present fifth embodiment, the inner-end area <NUM> and the outer-end area <NUM> are defined by the surfaces of each of the legs <NUM>. Because the inner-end area <NUM> has two inclined surfaces with respect to the virtual line RL that bisects it, less of the detection light and the reflected light is blocked by the legs <NUM> as the rotary body <NUM> rotates relative to the legs <NUM>. In addition, because the outer-end area <NUM>, which is radially outward of the inner-end area <NUM>, has a greater cross-sectional area than the inner-end area <NUM> while minimizing blockage of the detection light and the reflected light during rotation of the rotary body <NUM>, the outer-end area <NUM> serves to impart additional strength to each of the legs <NUM>.

More specifically, the inner-end area <NUM> includes the first inner-end area (flat surface) 75A and the second inner-end area (flat surface) 75B, which are oppositely inclined (slanted) relative to the bisecting virtual line RL so as to form an isosceles triangle in plan view. Thereby, in both the rotational state (position) in which the leg <NUM> opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM> and the rotational state (position) in which the (same) leg <NUM> opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>, less of the detection and reflected light is blocked by each of the legs <NUM>.

The outer-end area <NUM> includes the first outer-end area 76A, which does not extend outward of a virtual extension of the surface of first inner-end area 75A in a first circumferential direction (e.g., clockwise) of the rotary body <NUM>, and the second outer-end area 76B, which does not extend outward of a virtual extension of the surface of second inner-end area 75B in a second circumferential direction (e.g., counterclockwise) of the rotary body <NUM>,. Thereby, in both the rotational state (position) in which the leg <NUM> opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM> and the rotational state (position) in which the leg <NUM> opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>, less of the reflected detection light is blocked by the outer-end area <NUM> of each of the legs.

In a modification of the present (fifth) embodiment, the outer-end area <NUM> does not have to be inclined in the opposite direction to that of the inner-end area <NUM>. The outer-end area <NUM> may have a flat side that is, for example, parallel to, or coincides with, virtual line RL.

<FIG> is a cross-sectional view that schematically shows one of the legs <NUM> according to this modified example of the fifth embodiment. Each of the legs <NUM> of this modified example includes: the first inner-end area 75A having the inner-end part <NUM> in the radial direction of rotational axis CX; and the first outer-end area 76A having the outer-end part 70T in the radial direction of rotational axis CX. When at least a portion of the leg <NUM> opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM>, the first inner-end area 75A is inclined such that it is parallel to, or coincides with, optical axis Xa of the light-emitting device <NUM>. The first outer-end area 76A is partially inclined, in the opposite direction to that of the first inner-end area 75A, with respect to virtual line RL. In the example shown in <FIG>, the surfaces of the leg <NUM> include a flat surface <NUM>, which coincides with virtual line RL shown in <FIG>. It is noted that, in the example shown in <FIG>, the first outer-end area 76A does not have to be partially inclined in the opposite direction to that of the first inner-end area 75A. The first outer-end area 76A may, for example, include a portion that is parallel to virtual line RL and a portion that is perpendicular to virtual line RL.

<FIG> is a cross-sectional view that schematically shows one of the legs <NUM> according to another modified example of the fifth embodiment. Each of the legs <NUM> of this modified example includes: the second inner-end area 75B having the inner-end part <NUM> in the radial direction of rotational axis CX; and the second outer-end area 76B having the outer-end part 70T in the radial direction of rotational axis CX. When at least a portion of the leg <NUM> opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>, the second inner-end area 75B is inclined such that it is parallel to, or coincides with, optical axis Xb of the light-receiving device <NUM>. The second outer-end area 76B is partially inclined, in the opposite direction to that of the second inner-end area 75B, with respect to virtual line RL, and is partially parallel to virtual line RL. In the example shown in <FIG>, the surfaces of the leg <NUM> include a flat surface <NUM>, which coincides with the virtual line RL shown in FIG> <NUM>. It is noted that, in the example shown in <FIG>, the second outer-end area 76B does not have to be partially inclined in the opposite direction to that of the second inner-end area 75B. The second outer-end area 76B may, for example, include a portion that is parallel to virtual line RL and a portion that is perpendicular to virtual line RL.

A sixth embodiment will now be explained. In the explanation below, structural elements the same as or equivalent to those in the embodiment described above are assigned the same symbols, and explanations thereof are abbreviated or omitted.

<FIG> is a cross-sectional view that schematically shows the light-emitting device <NUM>, the light-receiving device <NUM>, and the legs <NUM> according to the present (sixth) embodiment. As shown in <FIG>, the legs <NUM> are rotatable in the cross section orthogonal to rotational axis CX. That is, each of the legs <NUM> is respectively rotatable about axes that are each parallel to rotational axis CX.

Each leg <NUM> rotates such that, when it opposes (faces) the light-emitting surface <NUM> of the light-emitting device <NUM>, at least one of the corresponding first side surface <NUM> and the corresponding second side surface <NUM> is parallel to, or coincides with, optical axis Xa of the light-emitting device <NUM>. In addition, each leg <NUM> rotates such that, when it opposes (faces) the light-receiving surface <NUM> of the light-receiving device <NUM>, at least one of the corresponding first side surface <NUM> and the corresponding second side surface <NUM> is parallel to, or coincides with, optical axis Xb of the light-receiving device <NUM>.

According to the present (sixth) embodiment as explained above, each leg <NUM> can rotate such that, based on its location in the rotational direction of the rotary body <NUM>, the time during which the detection light, which is emitted from the light-emitting surface <NUM> as the rotary body <NUM> is rotating, is blocked by the leg <NUM> can be advantageously decreased. In addition, each leg <NUM> can rotate such that, based on its location in the rotational direction of the rotary body <NUM>, the time during which the detection light, which is reflected by one or more objects as the rotary body <NUM> is rotating, is blocked by the leg <NUM> can be advantageously decreased. In the present embodiment, too, a decrease in detection accuracy can be curtailed while increasing the strength or robustness of the legs <NUM>.

A seventh embodiment will now be explained. In the explanation below, structural elements the same as or equivalent to those in the embodiment described above are assigned the same symbols, and explanations thereof are abbreviated or omitted.

<FIG> is a cross-sectional view that schematically shows the light-emitting device <NUM>, the light-receiving device <NUM>, and the legs <NUM> according to the present (seventh) embodiment. As shown in <FIG>, the legs <NUM> are capable of revolving around rotational axis CX. In the present embodiment, the cover <NUM> and the legs <NUM> are one body (i.e. integrally formed with no seam therebetween) and are adapted/configured to revolve (orbit) together about rotational axis CX. The cover <NUM> and the legs <NUM> are adapted/configured to revolve relative to the support member <NUM> and the coupling member <NUM>.

In the present embodiment, the cover <NUM> and the legs <NUM> revolve such that the legs <NUM> are disposed in the optical path of the detection light emitted from the light-emitting device <NUM> and the optical path of the detection light that enters the light-receiving device <NUM>. In the present embodiment, too, a decrease in detection accuracy can be curtailed while increasing the strength of the legs <NUM>.

An eighth embodiment will now be explained. In the explanation below, structural elements the same as or equivalent to those in the embodiment described above are assigned the same symbols, and explanations thereof are abbreviated or omitted.

<FIG> and <FIG> are cross-sectional views that schematically show the light-emitting device <NUM>, the light-receiving device <NUM>, and modified legs <NUM> according to the present (eighth) embodiment. In the eighth embodiment, the legs <NUM> have a parallelogram shape in horizontal cross-section and thus the design of the legs <NUM> incorporates aspects of the above-described first and fifth embodiments.

More specifically, each of the legs <NUM> has a first pair of parallel sides (flat surfaces) 79B, 79D that will respectively coincide with the optical axis Xa at first and second rotational positions of the rotary body <NUM> relative to the legs <NUM>. Thus, parallel sides 79B, 79D respectively correspond to (e.g., are oriented in the same way as) the first (flat) side surface <NUM> and the second (flat) side surface <NUM>, which is parallel to the first side surface <NUM>, of the first embodiment. The orientation (angle) of side 79B also corresponds to the orientation (angle) of side 75B of the fifth embodiment. In <FIG>, the optical axis Xa coincides with side 79B.

Furthermore, each leg <NUM> of the eighth embodiment also has a second pair of parallel sides 79A, 79C that will respectively coincide with the optical axis Xb at third and fourth rotational positions of the rotary body <NUM> relative to the legs <NUM>. Thus, side 79A corresponds to (e.g., is oriented in the same way as) the first (flat) side surface <NUM> of the first embodiment. The orientation (angle) of side 79A also corresponds to the orientation (angle) of side 75A of the fifth embodiment. In <FIG>, the optical axis Xb coincides with side 79A.

Side 79C differs from the preceding embodiments because side 79C is arranged to coincide with optical axis Xb at the above-mentioned fourth rotational position of the rotary body <NUM> relative to the legs <NUM>.

Although sides 79B, 79D preferably coincide with the optical axis Xa at first and second rotational positions, respectively, of the rotary body <NUM> relative to the legs <NUM>, the sides 79B, 79D may be slightly oblique to the optical axis Xa when the optical axis Xa intersects the respective side 79B, 79D. For example, when the optical axis Xa intersects a middle point of side 79B, the optical axis Xa and side 79B may form an angle of <NUM>-<NUM>°. Similarly, when the optical axis Xa intersects a middle point of side 79D, the optical axis Xa and side 79D may form an angle of <NUM>-<NUM>°.

Likewise, although sides 79A, 79C preferably coincide with the optical axis Xb at third and fourth rotational positions, respectively, of the rotary body <NUM> relative to the legs <NUM>, the sides 79A, 79C may be slightly oblique to the optical axis Xb when the optical axis Xb intersects the respective side 79A, 79D. For example, when the optical axis Xb intersects a middle point of side 79A, the optical axis Xb and side 79A may form an angle of <NUM>-<NUM>°. Similarly, when the optical axis Xb intersects a middle point of side 79C, the optical axis Xb and side 79C may form an angle of <NUM>-<NUM>°.

The first pair of parallel (flat) sides 79B, 79D provides the same advantages as sides <NUM>, <NUM> of the first embodiment; namely, because sides 79B, 79D are parallel and respectively coincide with the optical axis Xa at the above-mentioned first and second rotational positions of the rotary body <NUM> relative to the legs <NUM>, the profile (in particular, the width in the circumferential direction of the rotary body <NUM>) of the legs <NUM> minimizes blocking of the light emitted from the light-emitting device <NUM> along optical axis Xa while the rotary body <NUM> is rotating relative to the legs <NUM>.

The second pair of parallel (flat) sides 79A, 79C are designed to minimize the blocking of reflected light to the light-receiving device <NUM> along optical axis Xb while the rotary body <NUM> is rotating relative to the legs <NUM>. That is, in the eight embodiment, reflected light is blocked only within a rotational range corresponding to the distance between the intersection of sides 79A, 79D and the intersection of sides 79B, 79C. Thus, the profile (in particular, the width in the circumferential direction of the rotary body <NUM>) of the legs <NUM> with respect to the optical axis Xb is reduced as compared to the first and fifth embodiments.

In <FIG> and <FIG>, the sides 79A-79D intersect each other to form corners or angles, whereby a parallelogram is formed. However, it is noted that the sides 79A-79D need not intersect to form angles (corners), but rather one or more of the sides 79A-79D may transition to its adjacent side 79A-79D along a curved or rounded path. In particular, the radially outermost corner (where sides 79C, 79D meet) may preferably be rounded to improve robustness and durability.

In <FIG> and <FIG>, the sides 79A-79D form a rhomboid, because the length of sides 79B, 79D is shorter than the length of sides 79A, 79C. Preferably, the length of sides 79B, 79D is <NUM>-<NUM>% shorter than the length of sides 79A, 79C, more preferably <NUM>-<NUM>% shorter. However, in alternate embodiments of the present invention, the sides 79A-79D may form a rhombus, in which all four sides 79A-79D have equal lengths, or even the length of sides 79B, 79D may be longer than the length of sides 79A, 79C, e.g., <NUM>-<NUM>% longer, more preferably <NUM>-<NUM>% longer.

In other exemplary embodiments of the present invention, the legs <NUM> may be designed as quadrilaterals in horizontal cross section, such that the quadrilaterals have a major or longer diagonal that coincides with a radial extension from the rotational axis CX. The minor or shorter diagonal of the quadrilateral intersects the major diagonal and is shorter in length than the major diagonal. The minor diagonal need not be perpendicular to the major diagonal and may form a largest angle with the major diagonal in the range of <NUM>-<NUM>°, <NUM>-<NUM>°, e.g., <NUM>-<NUM>°.

Furthermore, although the legs <NUM> of the eighth embodiment have two pairs of parallel sides, the legs <NUM> may have other quadrilateral cross-sections that have only one pair of (precisely parallel) sides (e.g., a trapezoid shape) or no pair of (precisely parallel) sides. One two, three or four of the corners of such a quadrilateral also may be rounded or curved instead of angled.

Thus, the autonomous cleaning device <NUM> of the eighth embodiment, which may optionally be a robotic vacuum has an optical sensor <NUM> that comprises: a rotary body <NUM> adapted/configured to rotate relative to a main body <NUM> about a rotational axis CX; a light-emitting device <NUM> provided on (e.g., affixed to) the rotary body <NUM>; a light-receiving device <NUM> provided on (e.g., affixed to) the rotary body <NUM>; a cover <NUM> disposed upward of the rotary body <NUM>; and legs <NUM> disposed around the rotary body <NUM> and supporting the cover <NUM> with respect to the main body <NUM>. In a cross section orthogonal to the rotational axis CX, the legs <NUM> have an at least substantially quadrilateral shape. Preferably, at a first rotational position of the rotary body <NUM> relative to the legs <NUM>, an optical axis Xa of the light-emitting device <NUM> coincides, or forms an angle less than <NUM>°, with a first surface 79B of one of the legs <NUM>. At a second rotational position of the rotary body <NUM> relative to the legs <NUM>, the optical axis Xa of the light-emitting device <NUM> coincides, or forms an angle less than <NUM>°, with a second surface 79D of the one of the legs <NUM>. At a third rotational position of the rotary body <NUM> relative to the legs <NUM>, an optical axis Xb of the light-receiving device <NUM> coincides, or forms an angle less than <NUM>°, with a third surface 79A of the one of the legs <NUM>. At a fourth rotational position of the rotary body <NUM> relative to the legs <NUM>, the optical axis Xb of the light-receiving device <NUM> coincides, or forms an angle less than <NUM>°, with a fourth surface 79C of the one of the legs <NUM>.

The at least substantially quadrilateral shape is preferably a parallelogram shape, more preferably a rhomboid shape, although it may be a rhombus shape.

One or more of the corners of the at least substantially quadrilateral shape is angled, e.g., at least two corners are angled, at least three corners are angled or all four corners are angled. In addition or in the alternative, one or more of the corners of the at least substantially quadrilateral shape is curved, e.g., at least two corners are curved, at least three corners are curved or all four corners are curved.

Although the above-described embodiments primarily concern a robotic vacuum (i.e. having a suctioning capability), the present invention is equally applicable any kind of autonomous cleaning device, such as including autonomous mopping robots, autonomous floor scrubbers, autonomous UV sterilizers, etc., or any kind of device that performs robotic mapping.

Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present invention and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved robotic vacuums and autonomous cleaning devices and methods of using the same.

Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present invention.

All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.

Although some aspects of the present disclosure have been described in the context of a device, it is to be understood that these aspects also represent a description of a corresponding method, so that each block, part or component of a device, such as the controller <NUM>, is also understood as a corresponding method step or as a feature of a method step. In an analogous manner, aspects which have been described in the context of or as a method step also represent a description of a corresponding block or detail or feature of a corresponding device, such as the controller <NUM>.

Depending on certain implementation requirements, exemplary embodiments of the controller <NUM> of the present disclosure may be implemented in hardware and/or in software. The implementation can be configured using a digital storage medium, for example one or more of a ROM, a PROM, an EPROM, an EEPROM or a flash memory, on which electronically readable control signals (program code) are stored, which interact or can interact with a programmable hardware component such that the respective method is performed.

Optical sensors (<NUM>) according to the present invention may be adapted/configured to simply collect and output data concerning objects in the surroundings of the optical sensor, such that the outputted data is analyzed by a controller, e.g., of the robotic vacuum and autonomous cleaning device. In the alternative, the controller for analyzing the data collected by the optical sensor may be integrated in the optical sensor, such that the optical sensor is fully capable of generating map and location data that may be output for use with or by another device.

A programmable hardware component can be formed by a processor, a computer processor (CPU = central processing unit), an application-specific integrated circuit (ASIC), an integrated circuit (IC), a computer, a system-on-a-chip (SOC), a programmable logic element, or a field programmable gate array (FGPA) including a microprocessor.

The digital storage medium can therefore be machine- or computer readable. Some exemplary embodiments thus comprise a data carrier or non-transient computer readable medium which includes electronically readable control signals that are capable of interacting with a programmable computer system or a programmable hardware component such that one of the methods described herein is performed. An exemplary embodiment is thus a data carrier (or a digital storage medium or a non-transient computer-readable medium) on which the program for performing one of the methods described herein is recorded.

In general, exemplary embodiments of the present disclosure, in particular the controller <NUM>, are implemented as a program, firmware, computer program, or computer program product including a program, or as data, wherein the program code or the data is operative to perform one of the methods when the program is executed by a processor or a programmable hardware component. The program code or the data can for example also be stored on a machine-readable carrier or data carrier. The program code or the data can be, among other things, source code, machine code, bytecode or another intermediate code.

A program according to an exemplary embodiment can implement one of the methods during its performing, for example, such that the program reads storage locations or writes one or more data elements into these storage locations, wherein switching operations or other operations are induced in transistor structures, in amplifier structures, or in other electrical, optical, magnetic components, or components based on another functional principle. Correspondingly, data, values, sensor values, or other program information can be captured, determined, or measured by reading a storage location. By reading one or more storage locations, a program can therefore capture, determine or measure sizes, values, variable, and other information, as well as cause, induce, or perform an action by writing in one or more storage locations, as well as control other apparatuses, machines, and components, and thus for example also perform complex processes using the device <NUM>.

Claim 1:
An autonomous cleaning device (<NUM>), such as a robotic vacuum (<NUM>), having an optical sensor (<NUM>) that comprises
a rotary body (<NUM>) adapted to rotate relative to a main body (<NUM>) about a rotational axis (CX),
a light-emitting device (<NUM>) provided on the rotary body (<NUM>),
a light-receiving device (<NUM>) provided on the rotary body (<NUM>),
a cover (<NUM>) disposed upward of the rotary body (<NUM>), and
legs (<NUM>) disposed around the rotary body (<NUM>) and supporting the cover (<NUM>) with respect to the main body (<NUM>),
characterized in that
(i) in a cross section orthogonal to the rotational axis (CX), each of the legs (<NUM>) comprises at least one surface (<NUM>, <NUM>, 75A, 75B) that is inclined with respect to a virtual radial line (RL) extending in a radial direction of the rotational axis (CX) such that it is parallel to, or coincides with, the optical axis (Xa) when at least a portion of one of the legs (<NUM>) faces a light-emitting surface (<NUM>) of the light-emitting device (<NUM>), wherein an optical axis (Xa) of the light-emitting device (<NUM>) is inclined with respect to the virtual radial line (RL),
and/or
(ii) in a cross section orthogonal to the rotational axis (CX), each of the legs (<NUM>) comprises at least one surface (<NUM>, <NUM>, 75A, 75B) that is inclined with respect to a virtual radial line (RL) extending in a radial direction of the rotational axis (CX) such that it is parallel to, or coincides with, the optical axis (Xb) when at least a portion of one of the legs (<NUM>) faces a light-receiving surface (<NUM>) of the light-receiving device (<NUM>), wherein an optical axis (Xb) of the light-receiving device (<NUM>) is inclined with respect to the virtual radial line (RL).