Control of an airflow appliance

Abstract

A controller 10 for an airflow appliance 16, the controller configured to control the airflow appliance to emit an airflow 18 towards a first portion of a target user 2 and determine a change in pose

Description

BACKGROUND Airflow appliances are used to output an airflow. A controller for an airflow appliance controls the airflow appliance based on at least one input to the controller. SUMMARY Examples of a first aspect of the present disclosure provide a controller for an airflow appliance, the controller configured to: control the airflow appliance to emit an airflow towards a first portion of a target user; determine a change in pose of the target user; and in response to the change in pose, control at least one of: (i) a temperature of the airflow; and (ii) a direction of the airflow such that the airflow is emitted towards a second portion of the target user. This may facilitate improved convenience of use of the airflow appliance for the target user as, for example, the first portion or the second portion the target user can be targeted based on the change of pose of the target user, without the target user having to manually direct or redirect the airflow. Further, this may allow improved target user thermal comfort by the temperature of the airflow being controlled based on the change of pose, for example, the temperature of the airflow being increased when the pose of the target user changes from standing to sitting. The controller may be configured to: receive an image from an imaging system; determine, based on the image received from the imaging system, a skeletal model of the target user, the skeletal model corresponding to coordinates of one or more body parts of the target user relative to the airflow appliance; determine, based on the skeletal model, a pose of the target user; and control, based on the coordinates of the one or more body parts of the target user and based on the pose, the airflow appliance to emit the airflow at a first temperature and / or in a first direction towards the first portion of the target user. Providing the controller configured to: determine, based on the skeletal model, a pose of the target user; and control, based on the coordinates of the one or more body parts of the target user and based on the pose, the airflow appliance to emit an airflow at a first temperature and / or in a first direction towards the first portion of the target user may facilitate improved convenience of use of the airflow appliance for the target user as, for example, one or more body part of the target user can be targeted or avoided based on the pose of the target user without the target user having to manually direct or redirect the airflow. Further, this may allow improved target user thermal comfort, as a preferred body part of the target user for the pose (e.g., face while the target user is sitting and legs while the target user is standing) can be targeted based on the pose of the target user without the target user having to manually target the airflow. Providing the controller configured to determine, based on the skeletal model, the pose of the target user, may facilitate improved determination of the pose of the target user compared to other models of the target user, for example using a bounding box around the target user, as the skeletal model may provide more information such as the orientation of one or more body parts of the target user. The skeletal model may comprise nodes and / or lines. The nodes may correspond to joints of the target user (e.g. elbows, knees, and wrists) and may be connected by the lines which may correspond to bones or groups of bones of the target user (e.g. femur, tibia and fibula, humerus, ulna and / or radius). Each node and / or line may have associated coordinates. The coordinates of the one or more body parts of the target user may be the coordinates of the nodes and / or the coordinates of the lines. The controller may be configured to, determine, based on a spatial configuration of the coordinates of the lines and / or the nodes, the pose. The controller may be configured to, determine, based on distances between coordinates of the lines and / or the nodes, the pose. The controller may be configured to, determine, based on the orientation of the lines, the pose. The controller may be configured to: determine, based on the coordinates of the one or more body parts of the target user, and based on the pose, an airflow target; and control, based on the airflow target, the airflow appliance to emit the airflow towards the airflow target. For example, the airflow target may be coordinates of a centroid of the skeletal model and / or the coordinates the of one or more body part of the target user. This may facilitate improved thermal comfort of the target user as the airflow target can be selected as preferred for the pose of the target user, e.g., with the target user in a sitting pose the target user may prefer the airflow target to be the target user’s face. The controller may be configured to: receive a further image from the imaging system; determine, based on the further image received from the imaging system, a further skeletal model of the target user, the further skeletal model corresponding to further coordinates of the one or more body parts of the target user relative to the airflow appliance; determine, based on the further skeletal model, a further pose of the target user; and control, based on the further coordinates of the one or more body parts of the target user and based on the further pose, the airflow appliance to emit the airflow at a second temperature and / or in a second direction towards the second portion of the target user. This may facilitate improved convenience of use of the airflow appliance for the target user as, for example, the target user can be targeted or avoided based on a change of pose of the target user (e.g., from the pose to the further pose) without the target user having to manually direct or redirect the airflow. Further, this may allow improved user thermal comfort by the temperature of the airflow being controlled based on the change of pose, for example, the temperature of the airflow being increased when the pose of the target user changes from the pose of standing to the further pose of sitting. The change in pose may be from the pose to the further pose. The controller may be configured to select, based on the skeletal model, the pose from a plurality of predetermined poses to determine the pose of the target user. The controller may be configured to select, based on the further skeletal model, the further pose from the plurality of predetermined poses to determine the further pose of the target user. Each pose of the plurality of poses may be respectively associated with parameters for control of the airflow appliance to emit the airflow. With the parameters being selected for a preferable airflow for each respective pose, this may facilitate improved thermal comfort of the target user by airflow appliance being controlled with a preferable airflow for the pose and / or further pose of the target user. The plurality of poses may comprise, for example: standing, sitting, lying, and / or squatting. Each pose of the plurality of poses may be respectively associated with a range of values of the skeletal model and / or the further skeletal model, e.g.: configurations of the coordinates of the lines and / or the nodes; distances between coordinates of the lines and / or the nodes; and orientations of the lines. These ranges of values of the skeletal model and / or the further skeletal model may be in a look-up-table which may be stored in storage that is readable by the controller. In some examples, the airflow appliance comprises the storage. In other examples, the airflow appliance does not comprise the storage, for example, with the storage being a server. In such examples, the controller may be configured to select, based on values of the skeletal model and / or the further skeletal model, the pose and / or the further pose respectively from a plurality of predetermined poses in the look-up-table. The look-up-table may also comprise parameters for the controller to control the airflow appliance to emit the airflow respectively associated with the poses of the plurality of predetermined poses. The controller may be configured to select, based on the skeletal model and / or the further skeletal model, the pose and / or the further pose respectively from a plurality of predetermined poses stored in a look-up-table in the storage, and control, based on parameters associated with the pose and / or the further pose in the look-up-table, the airflow appliance to emit the airflow. The controller may be configured to: determine, based on the further coordinates of the one or more body parts of the target user, and based on the further pose, a further airflow target; and control, based on the further airflow target, the airflow appliance to emit the airflow towards the further airflow target. This may allow improved target user thermal comfort, as a preferred airflow target following a change from the pose to the further pose may be targeted based on the change of pose without the target user having to manually target the airflow. For example, the airflow target might be a face of the target user when the target user goes from a pose of standing to a further pose of sitting. The controller may be configured to: estimate, based on at least one of: the pose, the further pose, the skeletal model, the further skeletal model, the coordinates of the one or more body parts of the target user, and the further coordinates of the one or more body parts of the target user, an estimated future pose of the target user; and control, based on the estimated future pose of the target user, the airflow appliance to emit the airflow at a third temperature and / or in a third direction towards a third portion of the target user. This may facilitate improved convenience of use of the airflow appliance for the target user as, for example, the target user can be targeted by the airflow based on the future pose of the target user without the target user having to manually direct or redirect the airflow. Further, this may allow improved target user thermal comfort, as the airflow appliance can emit the airflow at a third temperature based on the estimated future pose without the target user having to manually change the temperature. The controller may be configured to: determine, based on the estimated future pose of the target user, a future airflow target; and control, based on the future airflow target, the airflow appliance to emit the airflow towards the future airflow target. This may facilitate improved thermal comfort of the target user by the future airflow target being based on a preference associated with the estimated future pose. For example, with the estimated future pose being sitting, the future airflow target may be a preferred target, such as the target user’s face. The controller may be configured to: estimate, based on at least one of: the pose, the further pose, the skeletal model, the further skeletal model, the coordinates of the one or more body parts of the target user, and the further coordinates of the one or more body parts of the target user, estimated future coordinates of the one or more body parts of the target user relative to the airflow appliance; and control, based on the estimated future coordinates of the one or more body parts of the target user, the airflow appliance to emit the airflow at a third temperature and / or in a third direction towards a third portion of the target user. This may facilitate improved convenience of use of the airflow appliance for the target user as, for example, the target user can be targeted by the airflow based on the estimated future coordinates of the body parts of the target user without the target user having to manually direct or redirect the airflow. Further, this may allow improved target user thermal comfort, as the airflow appliance can emit the airflow at a third temperature based on the estimated future pose without the target user having to manually change the temperature. At least two of the first temperature, second temperature, and third temperature may be different to each other. At least two of the first direction, second direction, and third direction, may be different to each other. At least two of the first portion, second portion, and third portion of the target user may be different to each other. The controller may be configured to: determine, based on the estimated future coordinates of the one or more body parts of the target user, a future airflow target; and control, based on the future airflow target, the airflow appliance to emit the airflow. For example, the future airflow target may be estimated future coordinates of a centroid of the skeletal model and / or estimated future coordinates of the one or more body part of the target user. This may facilitate improved thermal comfort of the target user as the future airflow target being determined based on the estimated future coordinates of the one or more body parts of the target user may improve targeting of the target user by the airflow appliance. The controller may be configured to: determine, based on the pose and the further pose, an activity of the target user; and control, based on the activity, the airflow appliance to emit the airflow towards the first, second, or third portion of the target user. This may facilitate control of the airflow appliance to be tailored to the determined activity. For example, with the activity being determined as exercise, the controller may be configured to control the airflow appliance to cool the airflow and emit the airflow towards the first, second, or third portion of the target user. The controller may be configured to: determine, based on the image, an identity of the target user; and control, based on the identity of the target user, the airflow appliance to emit the airflow towards the first, second, or third portion of the target user. This may improve the convenience of use of the airflow appliance when the airflow appliance is in use as the target user’s identity can be used to tailor the control of the airflow appliance to emit the airflow in line with the target user’s preferences without the need for intervention of the target user. For example, the target user may have, stored in a look-up-table, predetermined parameters for control of the airflow appliance to emit the airflow associated with each pose of the plurality of predetermined poses. The look-up-table may be stored, e.g., in the storage. The controller may be configured to select from the look-up-table, based on the identity of the target user, and based on the pose, the parameters for control of the airflow appliance to emit the airflow; and control, based on the parameters, the airflow appliance to emit the airflow. The controller may be configured to: receive temperature data; and control, based on the temperature data, the airflow appliance to emit the airflow. This may facilitate improved convenience of use of the airflow appliance for the target user. For example, a desired temperature of the airflow for an ambient temperature can be selected without the target user having to manually select the temperature of the airflow. Further, this may allow improved target user thermal comfort, as a desired part of the target user (e.g., legs or head) can be targeted depending on the temperature data. For example, the airflow may be directed at the target user’s head when the ambient temperature is hot, and the airflow may be directed at the target user’s legs when the ambient temperature is cold without the target user having to manually target the airflow. The controller may be configured to: based on the temperature data, determine a buoyancy of the airflow; and control, based on the buoyancy of the airflow, the airflow appliance to emit the airflow. This may facilitate compensation for the buoyancy of the airflow affecting an airflow path of the airflow. For example, if a temperature of the airflow is greater than an ambient temperature, the airflow will rise due to buoyancy, and this may be compensated for. The controller may be configured to control, based on the temperature data, a heater of the airflow appliance to heat the airflow. This may facilitate the airflow appliance to provide improved thermal comfort to the target user when the controller is in use. The controller may be configured to control, based on the temperature data, a cooler of the airflow appliance to cool the airflow. This may facilitate the airflow appliance to provide improved thermal comfort to the target user when the controller is in use. The image and / or further image may comprise at least one of: infrared image data, visible-light image data, light detection and ranging data (LiDAR), and radio detection and ranging (radar) data. This may facilitate the controller, when in use, to more accurately identify the target user from the image, compared to an image consisting of other image data types and / or to more accurately determine coordinates of the one or more body parts of the target user, compared to an image and / or further image consisting of other image data types. The controller may be configured to receive audio data obtained by at least one audio sensor. The at least one audio sensor may facilitate identification of the target user, for example by speech recognition or a preset sound such as a clap or a phrase. The image and / or further image may comprise image data from a plurality of sources. Such images may be referred to as compound images. Compared to images not comprising image data from a plurality of sources, providing the image and / or further image comprising image data from a plurality of sources may facilitate the controller, when in use, to more accurately determine coordinates of the one or more body parts of the target user and / or to more accurately identify the target user from the image and / or the further image. The image and / or further image may be a three-dimensional image. The image and / or further image being a three-dimensional image may allow the controller to, when in use, more accurately determine the coordinates of the one or more body parts of the target user compared to the image and / or further image being a two-dimensional image because, e.g., such a three-dimensional image may allow calculation of the distance from the imaging system to the target user from the image and / or further image rather than requiring an inference or ranging data to be used. The image and / or further image may be two-dimensional. The image and / or further image being two-dimensional may allow the imaging system to be configured to acquire two-dimensional images, rather than a comparatively more expensive imaging system configured to acquire three-dimensional images, allowing the cost of the imaging system to be reduced. The image and / or further image being two-dimensional may allow the controller, when in use, to require less processing power to, based on the image and / or further image, determine coordinates of the one or more body parts of the target user and / or the further coordinates of the one or more body parts of the target user respectively compared to the image and / or further image being three-dimensional. The controller may be configured to determine the coordinates of the one or more body parts of the target user in the image and / or further image based on an inference from the image and / or further image. For example, the two-dimensional size of a reference object in the image and / or further image may be compared to the known actual size of the reference object to infer the distance from the imaging system to the reference object. This may facilitate, when the controller is in use, a determination of the coordinates of the one or more body parts of the target user and / or the further coordinates of the one or more body parts of the target user respectively in three-dimensional space from the image and / or further image. The two-dimensional size of the reference object in the image and / or further image may comprise a size in the image and / or a size in the further image respectively of at least a portion of the target user. The size in the image may be based on a separation distance in the image between at least two features belonging to the target user. The size in the further image may be based on a separation distance in the further image between at least two features belonging to the target user. In some examples, the separation distance in the image and / or the separation distance in the further image may be between the eyes of the target user, or between at least two nodes defined by the skeletal model of the target user. In such examples, the actual separation distance between the at least two features may be approximated using, e.g., an average separation distance between the at least two features, and therefore the distance from the imaging system to the target user may be approximated. In some examples, the separation distance in the image and / or the separation distance in the further image may be based on a number of pixels between the at least two features in the image and / or further image respectively. In other examples, the separation distance in the image and / or the separation distance in the further image may be based on a distance between coordinates of each of the at least two features estimated from the image and / or further image respectively. The inference may comprise a two-dimensional size in the image and / or further image of a head of the target user. In such examples, the actual size of the head of the target user may be approximated using, e.g., an average head size and therefore the distance from the imaging system to the head of the target user may be approximated. Head size has a proportionally lesser variance than the variance in other dimensions of other body parts such as torso length or height. So, an approximation using the average head size may be more accurate than other approximations, such as approximations using an average torso length. Thus, the inference comprising two-dimensional size in the image and / or further image of the head of the target user may facilitate a more accurate determination of the distance from the imaging system to the target user than inferences consisting of dimensions of another body part of the target user and therefore a more accurate determination of the coordinates of the one or more body parts of the target user and or the further coordinates of the one or more body parts of the target user. The inference may comprise a two-dimensional size of a head and shoulders of the target user. The controller may be configured to control at least one of: a motor to control a pitch of an airflow outlet from which the airflow appliance, when in use, emits the airflow; a motor to control a roll of the airflow outlet; or a motor to control a yaw of the airflow outlet. This may allow the controller, when in use, to direct the airflow. Pitch may be referred to as tilt. Yaw may be referred to as pan. The controller may be configured to control the airflow appliance to emit the airflow in at least one of: one axis (one of pitch, roll, and yaw), two axes (two of pitch, roll and yaw), and three axes (all of pitch, roll, and yaw). The controller may be configured to control, based on the coordinates of the body parts of the target user, based on the change in pose of the target user, and / or based on the pose, a heater of the airflow appliance to heat the airflow. This may facilitate the controller, when in use, to provide improved thermal comfort to the target user. The controller may be configured to control, based on the coordinates of the body parts of the target user, based on the change in pose of the target user, and / or based on the pose, a cooler of the airflow appliance to cool the airflow. This may facilitate the controller, when in use, to provide improved thermal comfort to the target user. In some examples, the controller may be part of or integrated within the airflow appliance. In other examples, the controller may be separate to the airflow appliance. A second aspect of the present disclosure provides a control system for an airflow appliance, the control system comprising: the controller of the first aspect; and an imaging system configured to output an image to the controller. The controller configured to: receive the image from the imaging system; determine, based on the image received from the imaging system, a skeletal model of the target user, the skeletal model corresponding to coordinates of one or more body parts of the target user relative to the airflow appliance; determine, based on the skeletal model, a pose of the target user; and control, based on the coordinates of the one or more body parts of the target user and based on the pose, the airflow appliance to emit the airflow at a first temperature and / or in a first direction towards the first portion of the target user. The imaging system may comprise at least one of: an infrared imaging system configured to obtain an infrared part of the image and / or the further image and output the infrared part of the image and / or the further image respectively to the controller; a visible-light imaging system configured to obtain a visible-light part of the image and / or the further image and output the visible-light part of the image and / or the further image respectively to the controller; a light detection and ranging (LiDAR) system configured to obtain a LiDAR part of the image and / or the further image and output the LiDAR part of the image and / or the further image respectively to the controller; and a radio detection and ranging (radar) system configured to obtain a radar part of the image and / or the further image and output the radar part of the image and / or the further image respectively to the controller. This may facilitate the control system, when in use, to more accurately identify the target user from the image and / or the further image, compared to an image and / or a further image consisting of other image data types. This may facilitate the control system, when in use, to more accurately determine the skeletal model of the target user and / or the further skeletal model of the target user, compared to an image and / or a further image respectively consisting of other image data types. A third aspect of the present disclosure provides an airflow appliance comprising the controller of the first aspect of the present disclosure, or the control system of the second aspect of the present disclosure. The airflow appliance may be floor-standing. This may allow the airflow appliance to be moved by the target user and / or placed freely by the target user without the need for, for example, being wall mounted or otherwise installed. That is, the airflow appliance may be portable. The airflow appliance may comprise a heater for heating the airflow when in use. This may facilitate the airflow appliance to provide improved thermal comfort to the target user when the airflow appliance is in use. The airflow appliance may comprise a cooler for cooling the airflow when in use. This may facilitate the airflow appliance to provide improved thermal comfort to the target user when the airflow appliance is in use. The airflow appliance may comprise at least one of: a fan, an air purifier, a heater, an air conditioner, a humidifier, or a dehumidifier. A fourth aspect of the present disclosure provides a method of controlling an airflow appliance, the method comprising: controlling the airflow appliance to emit an airflow towards a first portion of a target user; determining a change in pose of the target user; and in response to the change in pose, controlling at least one of: (i) a temperature of the airflow; and (ii) a direction of the airflow such that the airflow is emitted towards a second portion of the target user. The method may comprise: receiving an image from an imaging system; determining, based on the image received from the imaging system, a skeletal model of the target user, the skeletal model corresponding to coordinates of one or more body parts of the target user relative to the airflow appliance; determining, based on the skeletal model, a pose of the target user; and controlling, based on the coordinates of the one or more body parts of the target user and based on the pose, the airflow appliance to emit an airflow at a first temperature and / or in a first direction towards the first portion of the target user. The method may comprise: determining, based on the coordinates of the one or more body parts of the target user, and based on the pose, an airflow target; and controlling, based on the airflow target, the airflow appliance to emit the airflow towards the airflow target. The method may comprise: receiving a further image from the imaging system; determining, based on the further image received from the imaging system, a further skeletal model of the target user, the further skeletal model corresponding to further coordinates of the one or more body parts of the target user relative to the airflow appliance; and determining, based on the further skeletal model, a further pose of the target user; and controlling, based on the further coordinates of the one or more body parts of the target user and based on the further pose, the airflow appliance to emit the airflow at a second temperature and / or in a second direction towards the second portion of the target user. The method may comprise: selecting, based on the skeletal model and / or further skeletal model, the respective pose and / or further pose from a plurality of predetermined poses to determine the respective pose and / or further pose of the target user. The method may comprise: determining, based on the further coordinates of the one or more body parts of the target user, and based on the further pose, a further airflow target; and controlling, based on the further airflow target, the airflow appliance to emit the airflow towards the further airflow target. The method may comprise: estimating, based on at least one of: the pose, the further pose, the skeletal model, the further skeletal model, the coordinates of the one or more body parts of the target user, and the further coordinates of the one or more body parts of the target user, an estimated future pose of the target user; and controlling, based on the estimated future pose of the target user, the airflow appliance to emit the airflow at a third temperature and / or in a third direction towards a third portion of the target user. The method may comprise: determining, based on the estimated future pose of the target user, a future airflow target; and controlling, based on the future airflow target, the airflow appliance to emit the airflow towards the future airflow target. The method may comprise: estimating, based on at least one of: the pose, the further pose, the skeletal model, the further skeletal model, the coordinates of the one or more body parts of the target user, and the further coordinates of the one or more body parts of the target user, estimated future coordinates of the one or more body parts of the target user relative to the airflow appliance; and controlling, based on the estimated future coordinates of the one or more body parts of the target user, the airflow appliance to emit the airflow at the third temperature and / or in the third direction towards a third portion of the target user. The method may comprise: determining, based on the pose and the further pose, an activity of the target user; and controlling, based on the activity, the airflow appliance to emit the airflow. The method may comprise: determining, based on the image, an identity of the target user; and controlling, based on the identity of the target user, the airflow appliance to emit the airflow. The method may comprise: receiving temperature data; and controlling, based on the temperature data, the airflow appliance to emit the airflow. The method may comprise: controlling, based on the coordinates of the one or more body parts of the target user, based on the change of pose and / or based on the pose, the airflow appliance to emit the airflow in at least one of: one axis (one of pitch, roll, and yaw), two axes (two of pitch, roll, and yaw), and three axes (all of pitch, roll, and yaw). A fifth aspect of the present disclosure provides a non-transitory computer-readable storage medium comprising instructions that, when executed, cause operation of the controller of the first aspect, for example to perform the method of the fourth aspect. Optional features of aspects of the present disclosure may be equally applied to other aspects of the present disclosure, where appropriate. Brief Description of the Drawings Figure 1 schematically shows a top-down view of an example airflow appliance when in use; Figure 2 schematically shows an image and a further image obtained by an imaging system of the airflow appliance, the image and the further image with a skeletal model of a target user and a further skeletal model of a target user superimposed respectively; Figure 3 is a block diagram of a control system of the airflow appliance; and Figure 4 is a flow diagram of a method of controlling the airflow appliance. Detailed Description of the Invention An example airflow appliance 16 is described with reference to Figures 1 to 3. The airflow appliance 16 is a freestanding fan (e.g., a portable fan). The airflow appliance 16 has an imaging system 12, a user interface 34, a temperature sensor 36, a controller 10, an airflow outlet 14, an actuator assembly 60, an airflow inlet 20, a blower 62, and a heater 64. A control system 46 (shown in Figure 3) of the airflow appliance 16 includes the imaging system 12, the user interface 34, the temperature sensor 36, the controller 10, the actuator assembly 60, the blower 62, and the heater 64. The imaging system 12 has an integrated circuit, such as a charge-coupled device (CCD), configured to obtain an image 24 and a further image 26 of a scene located in front of the airflow appliance 16. In this example, a CCD has a 2D array of pixel elements that is configured to obtain images comprising 2D and visible-light data. The CCD is configured with sufficient resolution to resolve features of a face of a target user 2 of the airflow appliance, for example, at a distance of 5 metres. The imaging system 12 is connected to the controller 10 by a first data cable. The user interface 34 has user-operable controls for controlling operation of the airflow appliance 16, including, for example, a dial for controlling a speed of the blower 62, a button for powering on and off the airflow appliance 16, a first control for switching between operational modes, and a second control for manually adjusting a direction of a central axis 22 of the airflow outlet 14. The user interface 34 is connected to the controller 10 by a second data cable. Other user-operable controls are envisaged. The temperature sensor 36 has a first thermocouple configured to obtain first temperature data indicative of an ambient temperature and a second thermocouple configured to obtain second temperature data indicative of a temperature of an airflow 18 emitted by the airflow appliance 16. The temperature sensor 36 is connected to the controller 10 by a third data cable. The controller 10 is connected to the imaging system 12 by the first data cable, the user interface 34 by the second data cable, the temperature sensor 36 by the third data cable, the actuator assembly 60 by a fourth data cable, the blower 62 by a fifth data cable, and the heater 64 by a sixth data cable. The controller 10 has a computer processor, storage, and a printed circuit board (PCB). The storage is readable by the computer processor, and stores instructions for the computer processor, calibration data, and look-up tables. The PCB connects the computer processor to the storage, the first data cable, the second data cable, the third data cable, the fourth data cable, the fifth data cable, and the sixth data cable. The airflow outlet 14 is rotatable around about a first rotational axis (yaw), a second rotational axis (pitch), and a third rotational axis (roll). The first, second, and third rotational axes are mutually orthogonal. Rotation of the airflow outlet 14 about the first rotational axis causes a central axis 22 of the airflow outlet 14 to precess about the first rotational axis. Likewise, rotation of the airflow outlet 14 about the second rotational axis causes the central axis 22 to precess about the second rotational axis, and rotation of the airflow outlet 14 about the third rotational axis causes the central axis 22 to precess about the third rotational axis. Rotation about the first rotational axis adjusts the yaw of the airflow outlet 14, rotation about the second rotational axis adjusts the pitch of the airflow outlet 14, and rotation about the third rotational axis adjusts the roll of the airflow outlet 14. The actuator assembly 60 is attached to the airflow outlet 14. The actuator assembly 60 has a first motor 54, a second motor 56, and a third motor 58. Each of the first 54, second 56, and third motor 58 may be a servomotor. The first motor 54 is operable to adjust the yaw of the airflow outlet 14, the second motor 56 is operable to adjust the pitch of the airflow outlet 14, and the third motor 58 is operable to adjust the roll of the airflow outlet 14. The actuator assembly 60 is connected to the controller 10 by the fourth data cable. The blower 62 has a fourth motor and an impeller. The fourth motor is attached to the impeller and is operable to rotate the impeller. The impeller is fluidly connected to the airflow inlet 20 by a first airflow conduit, and to the heater 64 by a second airflow conduit. The blower 62 is connected to the controller 10 by the fifth data cable. The heater 64 has a heating element. The heater 64 is located downstream of the blower 62, is fluidly connected to the blower 62 by the second airflow conduit and is fluidly connected to the airflow outlet 14 by a third airflow conduit. The heating element is positioned between the airflow inlet 20 and the airflow outlet 14. A temperature of the heating element is dependent on an electrical current through the heating element. The heater 64 is connected to the controller 10 by the sixth data cable. In use, the airflow appliance 16 is powered on by a target user 2 by operating the button of the user interface 34. The airflow appliance 16 is then put into a pose detection mode by the target user 2 by operating the first control of the user interface 34. The user interface 34 outputs to the controller 10, by the second data cable, the user interface data including the instructions for the airflow appliance 16 to be powered on and be in the pose detection mode. The controller 10 receives the user interface data and accordingly powers on the airflow appliance 16 and operates in pose detection mode. In the pose detection mode the controller 10 controls the airflow appliance 16 to emit the airflow based on a pose of the target user 2. Firstly, the controller 10 instructs, by the first data cable, the imaging system 12 to obtain the image 24. Accordingly, the integrated circuit (e.g., a CCD) of the imaging system 12 obtains the image 24 of the target user 2 in a pose (shown in Figure 2 as standing). The controller 10 then receives image 24 from the imaging system 12 by the first data cable. The controller 10 uses the image 24 to determine a skeletal model 30 of the target user 2 using a computer vision algorithm. The skeletal model 30 corresponds to coordinates of body parts of the target user 2 relative to the airflow appliance 16. The controller 10 then determines the pose of the target user 2 by selecting the pose from a first look-up table based on the skeletal model 30. The first look-up table is stored in the storage and has a plurality of predetermined poses, with each pose of the plurality of predetermined poses respectively associated with a range of values of the skeletal model 30. Each of the plurality of predetermined poses is also associated, in the first look-up table, with respective parameters for control of the airflow appliance 16. The controller 10 looks up the parameters associated with the pose. The parameters include a first pose temperature of the airflow and a first portion of the target user 2. The controller 10 then determines, based on the on the coordinates of the body parts of the target user 2, and the first portion of the target user 2, a first direction for emission of the airflow towards the first potion of the target user 2. The controller 10 also uses the image 24 to determine facial recognition data associated with a face of the target user 2 using a facial recognition algorithm. The controller 10 then determines, based on the facial recognition data, an identity of the target user 2 using a second look-up table stored in the storage. The controller 10 also instructs, by the third data cable, the temperature sensor 36 to obtain the first temperature data and the second temperature data. Accordingly, the temperature sensor 36, with the first thermocouple and the second thermocouple respectively, obtains the first temperature data and the second temperature data. The controller 10 then receives the first temperature data and the second temperature data from the temperature sensor 36 by the third data cable. The controller 10 then determines, based on the first pose temperature, the first temperature data, the second temperature data and the identity of the target user 2, a first target temperature for the airflow 18. Then, the controller 10 controls the airflow appliance 16 to emit the airflow 18 in the first direction with the first target temperature. To achieve this, the controller 10 generates first output data for controlling the airflow appliance 16. The first output data is based on the first direction and the first pose temperature, and includes first target yaw, pitch, and roll values for the airflow outlet 14, a first target speed value, and the first target temperature. The first target yaw, pitch, and roll values are such that the central axis 22 of the airflow outlet 14 tracks the first portion of the target user 2 and thus the airflow 18 is emitted from the airflow outlet 14 in the first direction. The controller 10 then outputs the first target yaw, pitch, and roll values to the actuator assembly 60 by the fourth data cable, the first target speed value to the blower 60 by the fifth data cable, and the first target temperature value to the heater 64 by the sixth data cable. The actuator assembly 60 receives the first target yaw, pitch, and roll values from the controller 10 by the fourth data cable, and controls, the first 54, second 56, and third motor 58 to direct the central axis 22 of the airflow outlet 14 in the first direction. The blower 62 receives the first target speed value from the controller 10 by the fifth data cable, and controls the fourth motor. The fourth motor rotates the impeller which draws air in through the airflow inlet 20, from the airflow inlet 20 to the blower 62 by the first airflow conduit, from the blower 62 to the heater 64 by the second airflow conduit, from the heater 64 to the airflow outlet 14 by the third airflow conduit, and out of the airflow outlet 14, thus moving air through the airflow appliance 16 and causing emission of the airflow 18 from the airflow outlet 14. The heater 64 receives the first target temperature value from the controller 10 by the sixth data cable, and controls the electrical current through the heating element. Part of the air moving through the airflow appliance 16 from the airflow inlet 20 to the airflow outlet 14 by the heater contacts the heating element. Heat is transferred from the heating element to the air moving through the airflow appliance 16 and thus a temperature of the airflow 18 is controlled. In the pose detection mode the controller 10 also detects changes in a pose of the target user 2. If there is a change from the pose to a further pose, the controller 10 then controls the airflow appliance 16 to emit the airflow based on the further pose of the target user 2. Firstly, the controller 10 determines the further pose (shown as sitting in Figure 2) of the target user 2 based on a further image 26 of the target user 2. Similarly to as described above for the image 24, the further image 26 is obtained by the imaging system 12, and similarly to as described above for the pose, the further pose is determined by the controller 10 based on a further skeletal model 32 corresponding to further coordinates of the body parts of the target user 2. The further pose is then compared, by the controller 10, to the pose. If the further pose is different to the pose, the controller 10 determines there is a change in pose of the target user 2. With a change in pose of the target user 2, the controller 10 then determines a second target temperature, and a second direction for emission of the airflow towards a second potion of the target user 2. Both the second target temperature and the second direction are determined by the controller 10 from the further image 26 using the same method as described above for determination of the first direction and the first target temperature from the image 24. Then, the controller 10 controls the airflow appliance 16 to emit the airflow 18 in the second direction with the second target temperature using the same method as described above for emitting the airflow 18 in the first direction with the first target temperature. Further, with the airflow appliance 16 in the pose detection mode, the controller 10 also estimates changes in pose of the target user 2 and controls the airflow appliance 16 accordingly. The controller 10 estimates, using a machine learning algorithm, an estimated future pose of the target user 2, and estimated future coordinates of the body parts of the target user 2 relative to the airflow appliance 16. These estimations are based on the pose, the further pose, the skeletal model 30, the further skeletal model 32, the coordinates of the body parts of the target user 2, and the further coordinates of the body parts of the target user 2. The future pose is then compared, by the controller 10, to the further pose. If the future pose is different to the further pose, there is an estimated change in pose of the target user 2. With the estimated change in pose of the target user 2, the controller 10, then determines, using a third look-up table and based on the pose and the further pose, an activity of the target user 2. The third look-up table has a plurality of predetermined activities each respectively associated with a plurality of poses and is stored in the storage. The controller 10 then determines, based on the future pose, the future coordinates of the body parts of the target user 2, and the activity of the target user 2, a future airflow target, a third pose temperature and a third direction towards a third portion of the target user 2. The controller 10 then controls the airflow appliance 16 to emit the airflow 18 in the third direction with the third target temperature using the same method as described above for emitting the airflow 18 in the first direction with the first target temperature. Pose detection mode can suspended by the target user 2 using the user interface 34, and the direction of the central axis 22 of the airflow output 14 can controlled manually by the target user 2. The airflow appliance 16 may facilitate improved convenience of use of the airflow appliance 16 for the target user 2 as, for example, the first portion or the second portion the target user 2 can be targeted based on the change of pose of the target user 2, without the target user 2 having to manually direct the airflow 18. Further, the airflow appliance 16 may allow improved target user 2 thermal comfort by the temperature of the airflow 18 being controlled based on the change of pose, for example, the temperature of the airflow 18 being increased when the pose of the target user 2 changes from standing to sitting. A method 66 in accordance with the above is illustrated in the flow diagram of Figure 4. The 5 method 66 comprises 68 controlling the airflow appliance 16 to emit an airflow 18 towards a first portion of a target user 2 and determining 70 a change in pose of the target user 2. The method 66 includes, in response to the change in pose, controlling 72 at least one of: (i) a temperature of the airflow 18; and (ii) a direction of the airflow 18 such that the airflowl8 is emitted towards a second portion of the target user 2. 10 Although the airflow appliance 16 is described above as controlling both the direction of the airflow 18 and the temperature of the airflow 18, alternative airflow appliances which only control the direction of the airflow 18 or the temperature of the airflow 18 in response to change in pose of the target user 2 are also envisaged. 15 Whilst examples and embodiments have thus far been described, these are illustrative only and various modifications may be made without departing from the scope of the invention as defined by the claims.

Claims

1. A controller for an airflow appliance, the controller configured to:control the airflow appliance to emit an airflow towards a first portion of a target user; determine a change in pose of the target user; andin response to the change in pose, control at least one of:(i) a temperature of the airflow; and(ii) a direction of the airflow such that the airflow is emitted towards a second portion of the target user.

2. The controller of claim 1, configured to:receive an image from an imaging system;determine, based on the image received from the imaging system, a skeletal model of the target user, the skeletal model corresponding to coordinates of one or more body parts of the target user relative to the airflow appliance;determine, based on the skeletal model, a pose of the target user; andcontrol, based on the coordinates of the one or more body parts of the target user and based on the pose, the airflow appliance to emit the airflow at a first temperature and / or in a first direction towards the first portion of the target user.

3. The controller of claim 2, configured to:determine, based on the coordinates of the one or more body parts of the target user, and based on the pose, an airflow target; andcontrol, based on the airflow target, the airflow appliance to emit the airflow towards the airflow target.

4. The controller of claim 2 or claim 3, configured to:receive a further image from the imaging system;determine, based on the further image received from the imaging system, a further skeletal model of the target user, the further skeletal model corresponding to further coordinatesof the one or more body parts of the target user relative to the airflow appliance;determine, based on the further skeletal model, a further pose of the target user; and,control, based on the further coordinates of the one or more body parts of the target user and based on the further pose, the airflow appliance to emit the airflow at a second temperature and / or in a second direction towards the second portion of the target user.

5. The controller of claim 4, configured to select, based on the skeletal model and / or further skeletal model, the respective pose and / or further pose from a plurality of predetermined poses to determine the respective pose and / or further pose of the target user.

6. The controller of claim 4 or claim 5, configured to:determine, based on the further coordinates of the one or more body parts of the target user, and based on the further pose, a further airflow target; andcontrol, based on the further airflow target, the airflow appliance to emit the airflow towards the further airflow target.

7. The controller of any of claims 4 to 6, configured to:estimate, based on at least one of:the pose,the further pose,the skeletal model,the further skeletal model,the coordinates of the one or more body parts of the target user, andthe further coordinates of the one or more body parts of the target user,an estimated future pose of the target user; andcontrol, based on the estimated future pose of the target user, the airflow appliance to emit the airflow at a third temperature and / or in a third direction towards a third portion of the target user.

8. The controller of claim 7, configured to:determine, based on the estimated future pose of the target user, a future airflow target; andcontrol, based on the future airflow target, the airflow appliance to emit the airflow towards the future airflow target.

9. The controller of claim 6, configured to:estimate, based on at least one of:the pose,the further pose,the skeletal model,the further skeletal model,the coordinates of the one or more body parts of the target user, andthe further coordinates of the one or more body parts of the target user, estimated future coordinates of the one or more body parts of the target user relative to the airflow appliance; andcontrol, based on the estimated future coordinates of the one or more body parts of the target user, the airflow appliance to emit the airflow at a third temperature and / or in a third direction towards a third portion of the target user.

10. The controller of claim 7 or claim 9, wherein at least one of:at least two of the first temperature, second temperature, and third temperature are different to each other;at least two of the first direction, second direction, and third direction, are different to each other; andat least two of the first portion, second portion, and third portion of the target user are different to each other.

11. The controller of any of claims 4 to 10, configured to:determine, based on the pose and the further pose, an activity of the target user; and control, based on the activity, the airflow appliance to emit the airflow.

12. The controller of any of claims 2 to 11, configured to:determine, based on the image, an identity of the target user; andcontrol, based on the identity of the target user, the airflow appliance to emit the airflow.

13. A control system for an airflow appliance, the control system comprising:the controller of any of claims 1 to 12; andan imaging system configured to output an image to the controller.

14. An airflow appliance comprising the controller of any of claims 1 to 12, or control system of claim 13.

15. A method of controlling an airflow appliance, the method comprising:controlling the airflow appliance to emit an airflow towards a first portion of a target user;determining a change in pose of the target user; andin response to the change in pose, controlling at least one of:(i) a temperature of the airflow; and(ii) a direction of the airflow such that the airflow is emitted towards a second portion of the target user.

16. The method of claim 15, comprising:receiving an image from an imaging system;determining, based on the image received from the imaging system, a skeletal model of the target user, the skeletal model corresponding to coordinates of one or more body parts of the target user relative to the airflow appliance;determining, based on the skeletal model, a pose of the target user; andcontrolling, based on the coordinates of the one or more body parts of the target user and based on the pose, the airflow appliance to emit an airflow at a first temperature and / or in a first direction towards the first portion of the target user.

17. The method of claim 16, comprising:determining, based on the coordinates of the one or more body parts of the target user, and based on the pose, an airflow target; andcontrolling, based on the airflow target, the airflow appliance to emit the airflow towards the airflow target.

18. The method of claim 16 or claim 17, comprising: receiving a further image from the imaging system;determining, based on the further image received from the imaging system, a further skeletal model of the target user, the further skeletal model corresponding to further coordinates of the one or more body parts of the target user relative to the airflow appliance; anddetermining, based on the further skeletal model, a further pose of the target user; andcontrolling, based on the further coordinates of the one or more body parts of the target user and based on the further pose, the airflow appliance to emit the airflow at a second temperature and / or in a second direction towards the second portion of the target user.

19. The method of claim 18, comprising selecting, based on the skeletal model and / or further skeletal model, the respective pose and / or further pose from a plurality of predetermined poses to determine the respective pose and / or further pose of the target user.

20. The method of claims 18 or 19, comprising:determining, based on the further coordinates of the one or more body parts of the target user, and based on the further pose, a further airflow target; andcontrolling, based on the further airflow target, the airflow appliance to emit the airflow towards the further airflow target.

21. The method of any of claims 18 to 20, comprising:estimating, based on at least one of:the pose,the further pose,the skeletal model,the further skeletal model,the coordinates of the one or more body parts of the target user, andthe further coordinates of the one or more body parts of the target user,an estimated future pose of the target user; andcontrolling, based on the estimated future pose of the target user, the airflow appliance to emit the airflow at a third temperature and / or in a third direction towards a third portion of the target user.

22. The method of claim 21, comprising:determining, based on the estimated future pose of the target user, a future airflow target; andcontrolling, based on the future airflow target, the airflow appliance to emit the airflow towards the future airflow target.

23. The method of claim 20, comprising:estimating, based on at least one of:the pose,the further pose,the skeletal model,the further skeletal model,the coordinates of the one or more body parts of the target user, andthe further coordinates of the one or more body parts of the target user, estimated future coordinates of the one or more body parts of the target user relative to the airflow appliance; andcontrolling, based on the estimated future coordinates of the one or more body parts of the target user, the airflow appliance to emit the airflow at the third temperature and / or in the third direction towards a third portion of the target user.

24. The method of any of claims 18 to 23, comprising:determining, based on the pose and the further pose, an activity of the target user; and controlling, based on the activity, the airflow appliance to emit the airflow.

25. The method of any of claims 16 to 24, comprising:determining, based on the image, an identity of the target user; andcontrolling, based on the identity of the target user, the airflow appliance to emit theairflow.

Images