Projection device and projection method for projection device
By integrating the camera unit, sensing unit and rotatable projection lens in the projection device, combined with the coordinated work of the processor and the rotation axis unit, the problem that the existing projection device cannot follow the user's movement and the projection direction is fixed, dynamic projection and all-round visual coverage are achieved, and projection effect and user experience are improved.
Patent Information
- Application Number
- CN202510451451.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-10
- Publication Date
- 2025-07-01
AI Technical Summary
The existing projection device cannot move with the user, and the projection direction is fixed, so it cannot achieve all-round visual coverage.
A projection device is designed, including an imaging unit, a sensing unit, a rotatable projection lens, a rotary shaft unit and a processor. The user image is acquired through the camera unit, the sensing unit senses the user distance, the processor determines the user's face coordinates and projection position, and controls the rotation axis unit to rotate the projection lens to achieve dynamic projection.
It realizes dynamic adjustment of projection position and angle according to user position, so that the projection content is always within the user's line of sight, improving projection effect and user experience.
Smart Images
Figure CN120238637A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the field of electronic technologies. More specifically, the present disclosure relates to a projection device and a projection method for a projection device. Background Art
[0002] With the development of technology, projection technology has become one of the important means of information display. Although the existing projection devices have significantly improved in clarity and brightness, most of them still have certain limitations. For example, the existing projection devices lack the ability to follow users and cannot be dynamically adjusted according to the movement or needs of users; the existing projection devices can only project in a fixed direction and cannot achieve omnidirectional visual coverage.
[0003] In summary, the existing projection devices have problems such as fixed viewing angle limitations and inability to follow projection. Summary of the Invention
[0004] An exemplary embodiment of the present disclosure is to provide a projection device and a projection method for a projection device, which can project to different positions or directions, and can follow the user for dynamic projection according to the position of the user, thereby improving the projection effect.
[0005] According to an exemplary embodiment of the present disclosure, a projection device is provided, including: a camera unit configured to acquire a user image; a sensing unit configured to sense the user distance from the user's face to the projection device; a projection unit including a rotatable projection lens; a rotation shaft unit configured to rotate the rotatable projection lens of the projection unit; and a processor configured to: obtain user face key points and a user head pose from the user image, where the user head pose includes a pitch angle, a direction angle, and a roll angle of the user's head; determine a user face coordinate and a projection position of the projection device based on the user face key points, the user head pose, and the user distance; determine a projection pose and lens parameters of the rotatable projection lens based on the user face coordinate and the projection position; and control the rotation shaft unit to rotate the rotatable projection lens to the determined projection pose, and set the rotatable projection lens based on the determined lens parameters for projection, thereby achieving projection to different positions or directions, and achieving dynamic projection following the user according to the position of the user, so that the projection content always remains within the user's line of sight, and the user can clearly see the projection content at different positions and angles, thereby improving the projection effect and enhancing the user experience.
[0006] Optionally, the projection unit may further include a fixed projection lens, which can be configured to project at a fixed position.
[0007] Optionally, the processor may be configured to: obtain the rotation angle of the imaging unit when acquiring the user image; determine the user face coordinates based on the rotation angle, the user face key points, and the user distance; determine a rotation matrix based on the user head pose; and determine the projection position based on the rotation matrix and the user face coordinates.
[0008] Optionally, the rotation shaft unit includes an azimuth rotation shaft body and a pitch rotation shaft body. Wherein, the processor may be configured to: control the azimuth rotation shaft body and the pitch rotation shaft body to rotate the rotatable projection lens to the projection pose.
[0009] Optionally, the processor may be configured to: find the lens parameters of the position closest to the projection position from the stored lens parameters by a nearest neighbor search method based on the projection position; perform interpolation operation on the found lens parameters of the position closest to the projection position by a parameter interpolation method, and use the interpolation operation result as the lens parameters; calculate an alignment vector from the projection position to the user face coordinates based on the projection position and the user face coordinates; determine the azimuth rotation angle of the azimuth rotation shaft body and the pitch rotation angle of the pitch rotation shaft body based on the alignment vector; and use the azimuth rotation angle and the pitch rotation angle as the projection pose.
[0010] Optionally, the sensing unit is further configured to sense the position and moving speed of the user. Wherein, the projection device further includes a moving unit configured to drive the projection device to move. And wherein, the processor may be configured to: predict at least one future position of the user based on the position and moving speed of the user; determine a predicted path of the projection device based on the at least one future position; and control the moving unit to drive the projection device to move based on the predicted path.
[0011] Optionally, the rotatable projection lens may include a negative refractive index lens and a projection lens group. And wherein, the negative refractive index lens is located in front of the projection lens group, and the negative refractive index lens rotates synchronously with the projection lens group.
[0012] Optionally, the processor is configured to: determine the pose change rate of the projection pose based on the projection pose and the current projection pose of the rotation shaft unit; control the rotation shaft unit to rotate the rotatable projection lens to the determined projection pose based on the pose change rate exceeding a first threshold; determine the parameter change rate of the lens parameters based on the lens parameters and the current lens parameters of the rotation shaft unit; and set the rotatable projection lens based on the lens parameters based on the parameter change rate exceeding a second threshold.
[0013] According to an exemplary embodiment of the present disclosure, a projection method for a projection device is provided. The projection device includes a camera unit, a sensing unit, a projection unit including a rotatable projection lens, a rotation axis unit, and a processor. The method includes: acquiring a user image through the camera unit; acquiring a user distance from the user's face to the projection device through the sensing unit; acquiring user face key points and a user head pose from the user image, where the user head pose includes a pitch angle, a yaw angle, and a roll angle of the user's head; determining user face coordinates and a projection position of the projection device based on the user face key points, the user head pose, and the user distance; determining a projection pose and lens parameters of the rotatable projection lens based on the user face coordinates and the projection position; and controlling the rotation axis unit to rotate the rotatable projection lens to the determined projection pose, and setting the rotatable projection lens based on the determined lens parameters for projection, thereby achieving projection to different positions or directions, and achieving dynamic projection following the user according to the user's position, so that the projection content always remains within the user's line of sight, and the user can clearly see the projection content at different positions and angles, thereby improving the projection effect and enhancing the user experience.
[0014] Optionally, the determining user face coordinates and a projection position of the projection device based on the user face key points, the user head pose, and the user distance may include: acquiring a rotation angle of the camera unit when acquiring the user image; determining the user face coordinates based on the rotation angle, the user face key points, and the user distance; determining a rotation matrix based on the user head pose; and determining the projection position based on the rotation matrix and the user face coordinates.
[0015] Optionally, the rotation axis unit includes a yaw angle rotation axis body and a pitch angle rotation axis body. The controlling the rotation axis unit to rotate the rotatable projection lens to the determined projection pose may include: controlling the yaw angle rotation axis body and the pitch angle rotation axis body to rotate the rotatable projection lens to the projection pose.
[0016] Optionally, determining the projection pose and the lens parameters based on the user's face coordinates and the projection position may include: based on the projection position, looking up the lens parameters of the position closest to the projection position from the stored lens parameters through a nearest neighbor search method; performing an interpolation operation on the lens parameters of the position closest to the projection position found through the parameter interpolation method, and using the result of the interpolation operation as the lens parameters; based on the projection position and the user's face coordinates, calculating an alignment vector from the projection position to the user's face coordinates; based on the alignment vector, determining the direction angle rotation angle of the direction angle rotation axis body and the pitch angle rotation angle of the pitch angle rotation axis body; and using the direction angle rotation angle and the pitch angle rotation angle as the projection pose.
[0017] Optionally, the projection device may further include a moving unit, wherein the projection method may further include: sensing the position and moving speed of the user through the sensing unit; predicting at least one future position of the user based on the position and moving speed of the user; determining a predicted path of the projection device based on the at least one future position; and controlling the moving unit to drive the projection device to move based on the predicted path.
[0018] Optionally, controlling the rotation shaft unit to rotate the rotatable projection lens to the determined projection pose and setting the rotatable projection lens based on the determined lens parameters for projection may include: determining a pose change rate of the projection pose based on the projection pose and the current projection pose of the rotation shaft unit; controlling the rotation shaft unit to rotate the rotatable projection lens to the determined projection pose based on the pose change rate exceeding a first threshold; determining a parameter change rate of the lens parameters based on the lens parameters and the current lens parameters of the rotation shaft unit; and setting the rotatable projection lens based on the lens parameters based on the parameter change rate exceeding a second threshold.
[0019] According to an exemplary embodiment of the present disclosure, there is provided a computer-readable storage medium having a computer program stored thereon, which when executed by a processor, implements a projection method for a projection device according to an exemplary embodiment of the present disclosure.
[0020] According to an exemplary embodiment of the present disclosure, there is provided a computing device including: at least one processor; and at least one memory storing a computer program, which when executed by the at least one processor, implements a projection method for a projection device according to an exemplary embodiment of the present disclosure.
[0021] According to an exemplary embodiment of the present disclosure, there is provided a computer program product, and instructions in the computer program product can be executed by a processor of a computer device to complete a projection method for a projection device according to the exemplary embodiment of the present disclosure.
[0022] For a projection device and a projection method for the projection device according to an exemplary embodiment of the present disclosure, a user image is acquired through an imaging unit of the projection device; a user distance from the user's face to the projection device is acquired through a sensing unit of the projection device; user face key points and a user head pose are acquired from the user image, where the user head pose includes a pitch angle, a direction angle, and a roll angle of the user's head; based on the user face key points, the user head pose, and the user distance, user face coordinates and a projection position of the projection device are determined; based on the user face coordinates and the projection position, a projection pose and lens parameters of a rotatable projection lens of the projection device are determined; and a rotation shaft unit of the projection device is controlled to rotate the rotatable projection lens of the projection device to the determined projection pose, and the rotatable projection lens of the projection device is set based on the determined lens parameters for projection, thereby achieving adjustment of the projection angle and parameters for projection to different positions or directions, and achieving dynamic projection according to the position of the user, so that the projection content always remains within the user's line of sight, and the user can clearly see the projection content at different positions and angles, thereby improving the projection effect and enhancing the user experience.
[0023] Additional aspects and / or advantages of the general concept of the present disclosure will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the general concept of the present disclosure. Brief Description of the Drawings
[0024] Through the following description with reference to the drawings that exemplarily show embodiments, the above and other objects and features of the exemplary embodiments of the present disclosure will become clearer, where: Figure 1 A block diagram of a projection device according to an exemplary embodiment of the present disclosure is shown; Figure 2 A schematic diagram of a projection lens group according to an exemplary embodiment of the present disclosure is shown; Figure 3 A block diagram of another projection device according to an exemplary embodiment of the present disclosure is shown; Figure 4 A schematic diagram of a projection device according to an exemplary embodiment of the present disclosure is shown; Figure 5 A flowchart of a projection method for a projection device according to an exemplary embodiment of the present disclosure is shown; Figure 6Schematic diagram showing an example process of aerial projection according to an exemplary embodiment of the present disclosure; Figure 7 Schematic diagram showing a dual-screen projection mode according to an exemplary embodiment of the present disclosure; Figure 8 Schematic diagram showing a lecture projection mode according to an exemplary embodiment of the present disclosure; Figure 9 Schematic diagram showing a follow-up projection mode according to an exemplary embodiment of the present disclosure; and Figure 10 Schematic diagram showing a computing device according to an exemplary embodiment of the present disclosure. Detailed Description of the Invention
[0025] Reference will now be made in detail to the exemplary embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings, wherein like reference numerals always refer to like parts. The embodiments will be described below with reference to the accompanying drawings in order to explain the present disclosure.
[0026] The present disclosure relates to a projection device (projector), in particular, a projection device equipped with a 360-degree rotatable secondary screen projection lamp and a negative refractive index lens for projecting a secondary screen in the air and implementing face tracking. The present disclosure relates to the application of projection technology and face recognition technology. The projection device in the present disclosure has a wide range of applications, including but not limited to education, commercial presentations, home entertainment, public exhibitions, and any occasion requiring a mobile display solution. Since the projection device in the present disclosure is equipped with a 360-degree rotatable projection lamp and the ability to project a secondary screen in the air, the projection device can form a secondary screen in the air to achieve an all-round visual display. Therefore, the projection device in the present disclosure is particularly suitable for occasions requiring dynamic display and interaction, such as virtual reality experiences, interactive games, and multi-angle visual demonstrations. In addition, the present disclosure may also relate to a movable projection device (projector), in particular, a projection device equipped with a mobile unit (such as, but not limited to, drive wheels), a 360-degree rotatable secondary screen projection lamp, and a negative refractive index lens for projecting a secondary screen in the air and implementing face tracking.
[0027] Figure 1 Block diagram showing a projection device according to an exemplary embodiment of the present disclosure. Figure 2 Schematic diagram showing a projection lens group according to an exemplary embodiment of the present disclosure. Figure 3 Block diagram showing another projection device according to an exemplary embodiment of the present disclosure. Figure 4 Schematic diagram showing a projection device according to an exemplary embodiment of the present disclosure.
[0028] In an exemplary embodiment of the present disclosure, as Figure 1As shown, the projection device includes: a camera unit 101, a sensing unit 102, a projection unit 103, a rotating shaft unit 104, and a processor 105.
[0029] The camera unit 101 is configured to acquire a user image. The sensing unit 102 is configured to sense the user distance from the user's face to the projection device. The projection unit 103 includes a rotatable projection lens 1031. The rotating shaft unit 104 is configured to rotate the rotatable projection lens of the projection unit. The processor 105 is configured to: obtain user face key points and the user's head pose from the user image, where the user's head pose includes the pitch angle, yaw angle, and roll angle of the user's head; determine the user face coordinates and the projection position of the projection device based on the user face key points, the user's head pose, and the user distance; determine the projection pose and lens parameters of the rotatable projection lens based on the user face coordinates and the projection position; and control the rotating shaft unit to rotate the rotatable projection lens to the determined projection pose, and set the rotatable projection lens based on the determined lens parameters for projection, so as to track the user's movement and perspective change and adjust the projection position to adapt to the user's movement and perspective change, making the projector more intelligent and personalized and enhancing the user experience. In addition, the camera unit 101 and the sensing unit 102 can also be connected to the rotating shaft unit 104, so that the rotating shaft unit 104 can rotate the camera unit 101 and the sensing unit 102.
[0030] In an exemplary embodiment of the present disclosure, as Figure 1 shown, the rotating shaft unit 104 can be connected to the rotatable projection lens 1031. The rotatable projection lens 1031 includes a negative refractive index lens and a projection lens group. Here, the negative refractive index lens is located in front of the projection lens group, and the negative refractive index lens rotates synchronously with the projection lens group. The rotatable projection lens 1031 can have a 360-degree rotation function.
[0031] Here, the negative refractive index lens may include a negative refractive index material. The negative refractive index material is a new type of material, and its characteristic is that it can make the incident angle and refraction angle of light on the same side of the normal. This characteristic can make the divergent light emitted by a light source on one side converge again on the other side, so as to re-image. When the user observes the light source on the other side of the negative refractive index lens, a floating projection in the air, that is, an aerial projection, will be observed. In addition, the negative refractive index lens is located in front of the sub-screen projection lens group and rotates synchronously with the projection lens to converge the projection light and form an image in the air.
[0032] The projection lens group may include a projection source and a variable-focus projection lens group. For example, as Figure 2As shown, the zoom projection lens group is located in front of the projection source. By changing the focal length of the lenses in the zoom projection lens group, the size of the imaging can be changed. Adjusting the focal length of the lenses in the zoom projection lens group can change the distance between the imaging plane and the lens. The projection lens group can change the pitch angle and the azimuth angle by relying on the azimuth angle rotation axis body and the pitch angle rotation receptor, and cooperate with the focal length and the focusing state of the lenses in the zoom projection lens group to change the aerial projection position in three degrees of freedom.
[0033] For example, the sensing unit 102 may include a sensor for obtaining the user distance. The sensor can be, for example, but not limited to, a Time of Flight (ToF) sensor. For example, the imaging unit 101 can be used to capture the user's face and the user's gesture postures, etc., and the ToF sensor is used to measure the distance between the user's face (human face) and the projection device.
[0034] In an exemplary embodiment of the present disclosure, the processor 105 may be configured to: obtain the rotation angle of the imaging unit when obtaining the user image; determine the user face coordinates based on the rotation angle, the user face key points, and the user distance; determine the rotation matrix based on the user head posture; determine the projection position based on the rotation matrix and the user face coordinates, so as to ensure that the projection image is accurately displayed within the user's field of view and improve the accuracy of the projection position. For example, the projection position may include the center coordinates of the projection position, and the user face coordinates may include the center coordinates of the user's eyes.
[0035] When determining the projection position, the position of the projection point may be calculated first in a local coordinate system with the center of the user's face as the origin of the coordinate system and the X-axis and Y-axis in the user's face. Then the position of the projection point in the local coordinate system is converted to the global coordinate system to obtain the projection position.
[0036] As an example, the coordinates of the projection area are calculated according to the user's position and direction. In the present disclosure, the target of the projection is a distance d in front of the human face on the projection plane p at. The position of the projection point in the local coordinate system can be calculated using the rotation matrix. Since the projection lens can be adjusted to be centered on the center of the user's face, the X-axis and Y-axis directions do not need to be corrected. Therefore, in the local coordinate system, the position of the projection point is (0, 0, d p ).
[0037] After that, the calculation from the local coordinate system to the global coordinate system is performed. In the global coordinate system, the rotation matrix is , and the user head posture is represented by Euler angles as: ( , , ). Here, Rx , R y , R z are rotation matrices around the x-axis, y-axis, and z-axis respectively.
[0038] Therefore, convert these Euler angles into a rotation matrix .
[0039] Use the rotation matrix and formula to convert the local coordinates (0, 0, d p ) to global coordinates. Here, x g 、y g 、z g are the values of the X-axis, Y-axis, and Z-axis of the projection position in the global coordinate system respectively, x f 、y f 、z f are the values of the X-axis, Y-axis, and Z-axis of the user's facial coordinates in the global coordinate system respectively.
[0040] In addition, when determining the projection position, the projection position can also be directly determined in the global coordinate system. Various related methods can be used to determine the projection position in the global coordinate system, and the present disclosure does not limit this.
[0041] In an exemplary embodiment of the present disclosure, the rotating shaft unit 104 may include a direction angle rotating shaft body and a pitch angle rotating shaft body. In this case, the processor 105 may be configured to: control the direction angle rotating shaft body and the pitch angle rotating shaft body to rotate the rotatable projection lens to the projection posture, thereby improving the accuracy of the rotated projection posture.
[0042] For example, the imaging unit 101, the sensing unit 102, and the rotatable projection lens 1031 can change the direction angle by rotating around the direction angle rotating shaft body of the rotating shaft unit 104, and the rotatable projection lens 1031 can change the pitch angle by rotating around the pitch angle rotating shaft body of the rotating shaft unit 104.
[0043] In an exemplary embodiment of the present disclosure, the processor 105 may be configured to: based on the projection position, find the lens parameters of the position closest to the projection position from the stored lens parameters by a nearest neighbor search method; perform an interpolation operation on the found lens parameters of the position closest to the projection position by a parameter interpolation method, and use the result of the interpolation operation as the lens parameters; based on the projection position and the user's face coordinates, calculate an alignment vector from the projection position to the user's face coordinates; based on the alignment vector, determine the azimuth rotation angle of the azimuth rotation axis body and the pitch angle of the pitch angle rotation axis body; and use the azimuth rotation angle and the pitch angle as the projection pose, thereby improving the accuracy of the projection pose and the lens parameters.
[0044] As an example, to ensure that the central coordinates of the projection position are aligned with the central coordinates of the user's eyes, in the present disclosure, the axes of the rotation shaft unit 104 (for example, the azimuth rotation axis body and the pitch angle rotation axis body) are precisely controlled. This includes calculating the correct direction and position of the rotatable projection lens so as to project with the central coordinates of the user's eyes as the center. An example of a detailed solution for achieving such alignment is shown below.
[0045] First, based on the user's face coordinates, determine the central coordinates of the user's eyes as: (x e , y e ); based on the projection position, determine the projection center coordinates as: (x g , y g ); calculate the alignment vector v from the projection center coordinates to the central coordinates of the user's eyes as v = (x e – x g , y e – y g ); use to normalize the alignment vector to obtain the direction vector d of the vector. Here, ; calculate the azimuth rotation angle θ and the pitch angle rotation angle θ x as the projection pose through the formula y so that the projection lens is aligned with the direction vector d; adjust the angle of the projection direction based on the projection pose (rotate the azimuth rotation axis body according to the value of θ x , and rotate the pitch angle rotation axis body according to the value of θ y ); adjust the focal length, focusing state, and direction of the rotatable projection lens 1031 or the secondary screen projection lens group 2 based on the lens parameters, which will ultimately affect the projection position of the projection position in space.
[0046] As an example, a calibration method can be used to adjust the focal length, focusing state, and direction of the rotatable projection lens 1031 or the secondary screen projection lens group 2. Sampling positions pre-distributed in space have pre-calibrated various distances to determine the focal length and focusing state parameters of the rotatable projection lens 1031 or the secondary screen projection lens group 2 (which can be abbreviated as the lens).
[0047] As an example, the calibration method may include the following three steps.
[0048] 1. Sampling position selection: Select a number of predetermined sampling positions (x i , y i , z i ) in space to cover the possible projection area.
[0049] 2. Calibration parameter recording: At each sampling position, record the focal length f i and the focusing state s i .
[0050] 3. Generation of a lookup table: Store the calibration parameters in a lookup table T. The lookup table T maps each sampling position to its corresponding parameters T(x i , y i , z i )=(f i ,s i ).
[0051] As an example, according to the projection center coordinates (x g ,y g ,z g ), find the closest pre-calibrated parameter set from the lookup table T, and generate the exact lens parameters (also called lens control parameters) by interpolating these parameters.
[0052] For example, the closest pre-calibrated parameter set can be found from the lookup table T through nearest neighbor search. In the lookup table T, first use a nearest neighbor search algorithm (such as a k-d tree or a ball tree) to find the k nearest neighbors of the input coordinates (x g ,y g ,z g ). Let the k nearest neighbors be (x i1 ,y i1 ,z i1 ),…,(x ik ,y ik ,z ik ). Then retrieve the calibration parameters corresponding to these nearest neighbors from the lookup table T, that is, (f i1 ,s i1 ),…,(f ik ,s ik)。Interpolate the retrieved parameter set to generate precise lens parameters (also known as lens control parameters).
[0053] For example, the retrieved parameter set can be interpolated by the Inverse Distance Weighting (IDW) interpolation method. The definition of the Inverse Distance Weighting (IDW) interpolation method is: . Here, d j is the Euclidean distance between the input coordinates and the j-th nearest neighbor, .
[0054] As an example, the lens parameters can be adjusted according to the interpolated parameters (f g , s g ). For example, modify the lens focal length so that the projection is focused at the desired distance f g . For example, fine-tune the focusing state s g to ensure clarity. By adjusting the angle and focus settings of the lens, it can be ensured that the projection is directly aligned in front of the user.
[0055] In an exemplary embodiment of the present disclosure, the processor 105 can be configured to: in response to detecting a user's face in the image captured by the imaging unit 101, control the imaging unit to rotate so that the user's face is at the center position of the image; obtain the image of the user's face at the center position as the user image, thereby improving the accuracy of the user image. For example, when the user's face is detected, the imaging unit 101 can be controlled to rotate horizontally to keep the user's face at the center position of the image.
[0056] In an exemplary embodiment of the present disclosure, the processor 105 can be configured to: based on the projection pose and the current projection pose of the rotation axis unit, determine the pose change rate of the projection pose; based on the pose change rate exceeding a first threshold, control the rotation axis unit to rotate the rotatable projection lens to the determined projection pose; based on the lens parameters and the current lens parameters of the rotation axis unit, determine the parameter change rate of the lens parameters; based on the parameter change rate exceeding a second threshold, set the rotatable projection lens based on the lens parameters, thereby by defining the timing of adjusting the projection pose and the timing of setting the rotatable projection lens, so that when projecting in real-time following the user, when the user's pose changes little, it is not necessary to always rotate the rotatable projection lens in real-time or set the rotatable projection lens based on the determined lens parameters.
[0057] In addition, in an exemplary embodiment of the present disclosure, the sensing unit 102 can also be configured to sense the position and movement speed of the user, such as Figure 3As shown, the projection device not only includes a camera unit 101, a sensing unit 102, a projection unit 103, a rotating shaft unit 104, and a processor 105, but may also include a moving unit 106 configured to drive the projection device to move. In this case, the processor 105 may also be configured to: predict at least one future position of the user based on the position and moving speed of the user; determine a predicted path of the projection device based on the at least one future position; control the moving unit 106 to drive the projection device to move based on the predicted path, thereby achieving path planning and motion control of the projection device. For example, the projection device is positioned and a navigation path is planned based on the position and moving speed of the user to control the projection device to move or perform motion according to the results of the positioning and navigation path planning.
[0058] The moving unit 106 may be, for example, but not limited to, a driving wheel. The moving unit 106 (driving wheel) can drive the projection device to move forward, backward, or turn, ensuring that the projection device can follow the user's movement, so that the projection device can be easily moved to any required place, improving the applicability of the projection device in different scenarios.
[0059] As an example, the processor 105 may rely on Simultaneous Localization and Mapping (SLAM for short) for positioning and navigation path planning. When performing positioning and navigation path planning, the processor 105 first determines the target position of the projection device, and then plans a path to reach the target position by maintaining a distance d between the projection device and the user.
[0060] When the processor 105 controls the projection device to move or perform motion, it determines the target position (x t , y t ) to which it will move or perform motion, and keeps the projection device at a distance d from the current position (x u , y u ) of the user.
[0061] When the processor 105 predicts the target position (x t , y t ), it needs to consider two aspects: the user's trajectory and the map layout. In terms of the user's trajectory, a Kalman Filter can be used to predict the user's future position. In terms of the map layout, for each candidate position, its feasibility can be evaluated according to the map layout. Specifically, it can be checked whether each candidate position is within free space (such as a grid occupancy map), and the cost of reaching each candidate position can be determined. For example, a cost map can be used to determine the cost of reaching each candidate position.
[0062] In addition, the processor 105 can use a Proportion Integration Differentiation (PID) controller to calculate a control signal. Assume e x =x t x r and e y =y t y r are the errors on the x-axis coordinate and y-axis coordinate respectively, where (x r , y r ) is the current position of the projection device. A Proportion Integration Differentiation controller can be used to calculate the control signals u x and u y : . Here, K p , K i and K d are constants. According to the control signals u x and u y , the speeds v l of the left motor and v r of the right motor of the projection device are adjusted.
[0063] In addition, in an exemplary embodiment of the present disclosure, the processor 105 can also be configured to: detect obstacles in the advancing routes of the projection device and the user; and in the case of detecting an obstacle, automatically adjust the projection posture (e.g., angle) and lens parameters of the secondary screen lens group to avoid the obstacle and remind the user.
[0064] In addition, in an exemplary embodiment of the present disclosure, as Figure 3 shown, the projection unit 103 not only includes a rotatable projection lens 1031, but may also include a fixed projection lens 1032, configured to perform projection at a fixed position, so that it can be used as a main screen projection unit for fixed projection. Here, the rotatable projection lens 1031 can be a secondary screen projection unit, and the fixed projection lens 1032 can be a main screen projection unit. As an example, the fixed projection lens 1032 can be a common projection lens and can project on a diffuse reflection plane.
[0065] As an example, as Figure 4 shown, a negative refractive index lens 1, a secondary screen projection lens group 2, a camera and sensors (e.g., a Time of Flight (ToF) sensor) 3, a direction angle rotation shaft body 4, a pitch angle rotation shaft body 5, a main screen projection lens 6, and drive wheels 7 can be provided on the body of the projection device.
[0066] The above has been described in conjunction with Figures 1 to 4 the projection device and its units according to exemplary embodiments of the present disclosure. Hereinafter, reference will be made to Figures 5 - 9 describe a projection method for a projection device according to an exemplary embodiment of the present disclosure.
[0067] Figure 5 A flowchart showing a projection method for a projection device according to an exemplary embodiment of the present disclosure is shown. Figure 5 The projection method for the projection device in
[0068] Referring to Figure 5 , in step S501, a user image is acquired through the imaging unit.
[0069] In an exemplary embodiment of the present disclosure, acquiring a user image through the imaging unit may include: in response to detecting a user's face in an image captured by the imaging unit; controlling the imaging unit to rotate so that the user's face is at the center position of the image; and acquiring an image of the user's face at the center position as the user image, thereby improving the accuracy of the user image. For example, when the user's face is detected, the imaging unit may be controlled to rotate horizontally to keep the user's face at the center position of the image.
[0070] In step S502, the user distance from the user's face to the projection device is acquired through the sensing unit.
[0071] In step S503, user face key points and the user's head pose are acquired from the user image. Here, the user's head pose includes the pitch angle, yaw angle, and roll angle of the user's head.
[0072] In step S504, based on the user face key points, the user's head pose, and the user distance, the user face coordinates and the projection position of the projection device are determined.
[0073] In an exemplary embodiment of the present disclosure, determining the projection pose and lens parameters of the rotatable projection lens based on the user's facial key points, the user's head pose, and the user's distance may include: obtaining the rotation angle of the imaging unit when acquiring the user image; determining the user's facial coordinates based on the rotation angle, the user's facial key points, and the user's distance; determining a rotation matrix based on the user's head pose; and determining the projection position based on the rotation matrix and the user's facial coordinates, so as to ensure that the projected image is accurately displayed within the user's field of view and improve the accuracy of the projection position. For example, the user's facial coordinates may be determined by combining the user's facial key points obtained from the user image, the user's distance, and the rotation angle of the camera.
[0074] In step S505, determine the projection pose and lens parameters of the rotatable projection lens based on the user's facial coordinates and the projection position.
[0075] In an exemplary embodiment of the present disclosure, determining the projection pose and the lens parameters based on the user's facial coordinates and the projection position may include: searching for the lens parameters of the position closest to the projection position from the stored lens parameters by the nearest neighbor search method based on the projection position; performing an interpolation operation on the found lens parameters of the position closest to the projection position by the parameter interpolation method, and using the interpolation operation result as the lens parameters; calculating an alignment vector from the projection position to the user's facial coordinates based on the projection position and the user's facial coordinates; determining the direction angle rotation angle of the direction angle rotation axis body and the pitch angle rotation angle of the pitch angle rotation axis body based on the alignment vector; and using the direction angle rotation angle and the pitch angle rotation angle as the projection pose, thereby improving the accuracy of the projection pose and the lens parameters.
[0076] In step S506, control the rotation shaft unit to rotate the rotatable projection lens to the determined projection pose, and set the rotatable projection lens based on the determined lens parameters for projection. In an exemplary embodiment of the present disclosure, controlling the rotation shaft unit to rotate the rotatable projection lens to the determined projection pose, and setting the rotatable projection lens based on the determined lens parameters for projection may include: determining the pose change rate of the projection pose based on the projection pose and the current projection pose of the rotation shaft unit; controlling the rotation shaft unit to rotate the rotatable projection lens to the determined projection pose based on the pose change rate exceeding a first threshold; determining the parameter change rate of the lens parameters based on the lens parameters and the current lens parameters of the rotation shaft unit; and setting the rotatable projection lens based on the lens parameters based on the parameter change rate exceeding a second threshold.
[0077] In an exemplary embodiment of the present disclosure, the rotation shaft unit may include a direction angle rotation shaft body and a pitch angle rotation shaft body. In this case, controlling the rotation shaft unit to rotate the rotatable projection lens to the determined projection posture may include: controlling the direction angle rotation shaft body and the pitch angle rotation shaft body to rotate the rotatable projection lens to the projection posture, thereby improving the accuracy of projection posture adjustment.
[0078] In addition, in an exemplary embodiment of the present disclosure, the projection device further includes a moving unit. In this case, the projection method may further include: sensing the position and moving speed of the user through the sensing unit; predicting at least one future position of the user based on the position and moving speed of the user; determining a predicted path of the projection device based on the at least one future position; controlling the moving unit to drive the projection device to move based on the predicted path.
[0079] In addition, in an exemplary embodiment of the present disclosure, when controlling the projection device to move based on the predicted path, obstacles in the advancing route of the user or the projection device may also be detected, and in the case of detecting an obstacle, the projection posture (e.g., angle) and lens parameters of the secondary screen lens group are automatically adjusted to avoid the obstacle and remind the user.
[0080] Figure 6 A schematic diagram showing an example process of aerial projection according to an exemplary embodiment of the present disclosure.
[0081] As Figure 6 shown, first, in step 1, an image (e.g., a user image in Figure 1 ) is captured by a camera (e.g., the imaging unit 101 in Figure 5 ) of the projection device, and the captured image is input into a face detection model. In step 2, the face region is determined by the face detection model. In step 3, based on the face region, face key points (e.g., user facial key points in Figure 5 ) are determined by a face key point model. In step 4, user head posture (e.g., user head posture in Figure 5 ) estimation is performed based on the face key points to obtain the user head posture (e.g., Euler angles). In step 5, the face distance (e.g., in Figure 5the distance of the user in). In step 6, 3D face coordinate calculation is performed based on the face key points and the face distance. In step 7, 3D projection center coordinate calculation in the local coordinate system is performed based on the user's head pose (e.g., Euler angles) and the 3D face coordinates. In step 8, 3D projection center coordinate calculation in the global coordinate system (e.g., projection position) is performed based on the 3D projection center coordinates in the local coordinate system. In step 9, projection lens control is performed based on the 3D projection center coordinates (e.g., projection position). In step 10, rotation control of the rotation shaft unit of the projection device is performed based on the 3D projection center coordinates (e.g., projection position). In step 11, aerial projection is performed.
[0082] Figure 7 shows a schematic diagram of a dual-screen projection mode according to an exemplary embodiment of the present disclosure. In Figure 7 the shown dual-screen projection mode, the main screen projection unit and the secondary screen projection unit can be used for projection. The main screen projection unit can be used to fixedly display content, and the secondary screen projection unit can move the projection screen following the movement of the user. As Figure 7 shown, the user can move within the projectable area of the secondary screen projection unit. In Figure 7 the shown dual-screen projection mode, the secondary screen projection unit can project following the face without affecting the projection of the main screen projection unit.
[0083] In the dual-screen projection mode, the face pose of the user (e.g., Figure 5 the head pose of the user in) is detected in real time. According to the detected face pose of the user (e.g., Figure 5 the head pose of the user in), the rotation angle (e.g., projection pose) and lens parameters of the lens group of the secondary screen projection unit that need to be adjusted are calculated. The rotation angle (e.g., projection pose) of the lens group of the secondary screen projection unit is adjusted to ensure that the secondary screen projection unit always projects within the user's line of sight. According to the user distance and the face pose of the user (e.g., Figure 5 the head pose of the user in), the focal length, focus state, and direction of the lens group of the secondary screen projection unit are adjusted to ensure that the projected image is clear and projected at a suitable position.
[0084] Figure 8 shows a schematic diagram of a speech projection mode according to an exemplary embodiment of the present disclosure. In Figure 8 the shown speech projection mode, the main screen projection unit and the secondary screen projection unit can be used for projection. The main screen can be used to project speech content (e.g., slide PPT content), and the secondary screen projection unit can be used to project a teleprompter in front of the user following the movement of the user. As Figure 8 shown, the user can stand in front of the main screen to give a speech.
[0085] In the speech projection mode, the main screen fixedly projects the speech content, and the lens group of the secondary screen projection unit is controlled to rotate to the same side as the lens of the main screen projection unit, ensuring that the user can see the teleprompter content projected by the secondary screen projection unit. The secondary screen projection unit projects the teleprompter content in front of the user's eyes, facilitating the user to view during the speech.
[0086] Figure 9 FIG. shows a schematic diagram of a follow - projection mode according to an exemplary embodiment of the present disclosure. The follow - projection mode can be used when the user is walking and using the secondary screen. In Figure 9 the shown follow - projection mode, it is supported that as the user moves, the projection device moves following the movement of the user's face position and projects. For example, in the follow - projection mode, the secondary screen projection unit can project the screen while moving by following the user.
[0087] In the follow - projection mode, the user's location and movement speed are detected in real - time. Based on the user's location and movement speed, the rotation angle (e.g., projection posture) and lens parameters of the secondary screen lens are adaptively updated in real - time to ensure that the projected content is always within the user's line of sight. In addition, in the follow - projection mode, obstacles in the user's forward route can also be detected. In the case of detecting an obstacle, the projection posture (e.g., angle) and lens parameters of the lens group of the secondary screen projection unit are automatically adjusted to avoid the obstacle and the user is reminded.
[0088] In addition, according to an exemplary embodiment of the present disclosure, there is also provided a computer - readable storage medium, on which a computer program is stored. When the computer program is executed, a projection method for a projection device according to an exemplary embodiment of the present disclosure is implemented.
[0089] In an exemplary embodiment of the present disclosure, the computer-readable storage medium may carry one or more programs, and when the computer program is executed, the following steps may be implemented: obtaining a user image through the imaging unit of the projection device; obtaining the user distance from the user's face to the projection device through the sensing unit of the projection device; obtaining user face key points and the user's head pose from the user image, where the user's head pose includes the pitch angle, azimuth angle, and roll angle of the user's head; determining the user face coordinates and the projection position of the projection device based on the user face key points, the user's head pose, and the user distance; determining the projection pose and lens parameters of the rotatable projection lens of the projection device based on the user face coordinates and the projection position; and controlling the rotation unit of the projection device to rotate the rotatable projection lens of the projection device to the determined projection pose, and setting the rotatable projection lens of the projection device based on the determined lens parameters for projection, thereby realizing projection to different positions or directions, and realizing dynamic projection following the user according to the user's position, so that the projection content always remains within the user's line of sight, and the user can clearly see the projection content at different positions and angles, thereby improving the projection effect and enhancing the user experience.
[0090] A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In an embodiment of the present disclosure, a computer-readable storage medium may be any tangible medium that contains or stores a computer program, and the computer program may be used by or in conjunction with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable storage medium may be transmitted by any appropriate medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above. A computer-readable storage medium may be contained in any device; it may also exist separately without being assembled into the device.
[0091] In addition, according to an exemplary embodiment of the present disclosure, a computer program product is further provided, and the instructions in the computer program product may be executed by a processor of a computer device to complete the projection method for a projection device according to the exemplary embodiment of the present disclosure.
[0092] The above has been combined with Figures 5 - 9A projection method for a projection device according to an exemplary embodiment of the present disclosure has been described. Next, in combination with Figure 10 A computing device according to an exemplary embodiment of the present disclosure will be described.
[0093] Figure 10 A schematic diagram showing a computing device according to an exemplary embodiment of the present disclosure.
[0094] Referring to Figure 10 , a computing device 1000 according to an exemplary embodiment of the present disclosure includes a memory 1001 and a processor 1002. A computer program is stored on the memory 1001. When the computer program is executed by the processor 1002, a projection method for a projection device according to an exemplary embodiment of the present disclosure is implemented.
[0095] In an exemplary embodiment of the present disclosure, when the computer program is executed by the processor 1002, the following steps can be implemented: obtaining a user image through an imaging unit of the projection device; obtaining a user distance from the user's face to the projection device through a sensing unit of the projection device; obtaining user face key points and a user head pose from the user image, where the user head pose includes a pitch angle, a direction angle, and a roll angle of the user's head; determining user face coordinates and a projection position of the projection device based on the user face key points, the user head pose, and the user distance; determining a projection pose and lens parameters of a rotatable projection lens of the projection device based on the user face coordinates and the projection position; and controlling a rotating shaft unit of the projection device to rotate the rotatable projection lens of the projection device to the determined projection pose, and setting the rotatable projection lens of the projection device based on the determined lens parameters for projection, thereby achieving projection to different positions or directions, and achieving dynamic projection following the user according to the user's position, so that the projection content always remains within the user's line of sight, and the user can clearly see the projection content at different positions and angles, thereby improving the projection effect and enhancing the user experience.
[0096] The computing device in the embodiments of the present disclosure may include, but is not limited to, devices such as mobile phones, laptop computers, PDAs (Personal Digital Assistants), PADs (Tablet Computers), desktop computers, etc. Figure 10 The shown computing device is only an example and should not impose any limitations on the functions and usage scope of the embodiments of the present disclosure.
[0097] The above has been referred to Figures 1 to 10 to describe a projection device and a projection method for a projection device according to an exemplary embodiment of the present disclosure. However, it should be understood that: Figures 1 - 4The aerial projection device and its units shown in [ID] can be respectively configured as software, hardware, firmware, or any combination of the above items that perform specific functions. Figure 10 The computing device shown in [ID] is not limited to including the components shown above, but some components can be added or deleted as needed, and the above components can also be combined.
[0098] According to the projection device and the projection method for the projection device of an exemplary embodiment of the present disclosure, a user image is acquired through the imaging unit of the projection device; a user distance from the user's face to the projection device is acquired through the sensing unit of the projection device; user face key points and a user head pose are acquired from the user image, where the user head pose includes a pitch angle, a direction angle, and a roll angle of the user's head; based on the user face key points, the user head pose, and the user distance, user face coordinates and a projection position of the projection device are determined; based on the user face coordinates and the projection position, a projection pose and lens parameters of the rotatable projection lens of the projection device are determined; and a rotation shaft unit of the projection device is controlled to rotate the rotatable projection lens of the projection device to the determined projection pose, and the rotatable projection lens of the projection device is set based on the determined lens parameters for projection, thereby realizing adjusting the projection angle and parameters to project to different positions or directions, and realizing dynamic projection following the user according to the user's position, so that the projection content always remains within the user's line of sight, and the user can clearly see the projection content at different positions and angles, thereby improving the projection effect and enhancing the user experience.
[0099] In addition, according to the projection device and the projection method for the projection device of an exemplary embodiment of the present disclosure, the projection focal length, focus state, and direction of a lens (for example, the lens group of the secondary screen projection unit) can be dynamically adjusted according to the user's distance and pose, ensuring the clarity and correct position of the projection image. This adaptive adjustment ability enables the projection system to provide the best projection effect in different usage scenarios, avoiding problems such as blurred projection or misaligned projection during the projection process.
[0100] In addition, according to the projection device and the projection method for the projection device of an exemplary embodiment of the present disclosure, it is not only applicable to the static main screen projection mode, but also can provide efficient projection services in dynamic scenarios such as lectures (for example, slide PPT lectures) and when the user is walking. Whether it is a teleprompter projection at a fixed position or a follow-up projection following the user's movement, the aerial projection method and device according to the exemplary embodiment of the present disclosure can provide a stable and clear projection effect, meeting the requirements of various application scenarios.
[0101] In addition, according to the projection device and the projection method for the projection device of the exemplary embodiments of the present disclosure, through gesture recognition and touch point coordinate calculation, an interactive function with the projection interface is realized. The user can directly control the projection content through gestures, enhancing the interactivity and convenience between the user and the projection system. This interactive experience significantly improves the usage experience of the projection system.
[0102] In addition, according to the projection device and the projection method for the projection device of the exemplary embodiments of the present disclosure, air projection can be performed without the need for a fixed screen or wall as the projection medium, improving the flexibility of projection in space.
[0103] Although the present disclosure has been specifically shown and described with reference to its exemplary embodiments, those skilled in the art should understand that various changes in form and detail may be made thereto without departing from the spirit and scope of the present disclosure defined by the claims.
Claims
1. A projection device, comprising: A camera unit configured to obtain an image of a user; a sensing unit configured to sense a user distance from a user's face to the projection device; A projection unit, including a rotatable projection lens; a rotating shaft unit, configured to rotate the rotatable projection lens of the projection unit; as well as The processor is configured as: Acquire user facial key points and user head posture from the user image, wherein the user head posture includes a pitch angle, a azimuth angle, and a roll angle of the user's head; Determine the user's facial coordinates and the projection position of the projection device based on the user's facial key points, the user's head posture and the user distance; Determining the projection posture and lens parameters of the rotatable projection lens based on the user face coordinates and the projection position; and The rotating shaft unit is controlled to rotate the rotatable projection lens to the determined projection posture, and the rotatable projection lens is set based on the determined lens parameters to perform projection.
2. The projection device according to claim 1, wherein: The projection unit further includes a fixed projection lens configured to perform projection at a fixed position.
3. The projection device according to claim 1, wherein: The processor is configured to: Obtaining a rotation angle of the camera unit when acquiring the user image; Determine the user's facial coordinates based on the rotation angle, the user's facial key points and the user distance; Determining a rotation matrix based on the user's head posture; The projection position is determined based on the rotation matrix and the user face coordinates.
4. The projection device according to claim 1, wherein: The rotating shaft unit includes an azimuth rotation shaft body and a pitch angle rotation shaft body, wherein the processor is configured to: The directional angle rotation axis and the pitch angle rotation axis are controlled to rotate the rotatable projection lens to the projection posture.
5. The projection device according to claim 4, wherein: The processor is configured to: Based on the projection position, searching the stored lens parameters for the position closest to the projection position by a nearest neighbor search method; Performing an interpolation operation on the lens parameters of the position closest to the projection position found by a parameter interpolation method, and using the interpolation operation result as the lens parameter; Based on the projection position and the user face coordinates, calculating an alignment vector from the projection position to the user face coordinates; Based on the alignment vector, determining the azimuth rotation angle of the azimuth rotation axis and the pitch angle rotation angle of the pitch angle rotation axis; The azimuth rotation angle and the pitch rotation angle are used as the projection posture.
6. The projection device according to claim 1, wherein: The sensing unit is further configured to sense the position and movement speed of the user, wherein the projection device further comprises a moving unit configured to drive the projection device to move, and Wherein, the processor is further configured to: predicting at least one future location of the user based on the location and movement speed of the user; determining a predicted path of the projection device based on the at least one future position; The moving unit is controlled to drive the projection device to move based on the predicted path.
7. The projection device according to claim 1, wherein: The rotatable projection lens comprises a negative refractive index lens and a projection lens group, and Wherein, the negative refractive index lens is located before the projection lens group, and the negative refractive index lens rotates synchronously with the projection lens group.
8. The projection device according to claim 1, wherein: The processor is configured to: Determining a posture change rate of the projection posture based on the projection posture and the current projection posture of the rotating shaft unit; Based on the attitude change rate exceeding a first threshold, controlling the rotation axis unit to rotate the rotatable projection lens to the determined projection attitude; Determining a parameter change rate of the lens parameter based on the lens parameter and a current lens parameter of the rotating shaft unit; Based on the parameter change rate exceeding a second threshold, the rotatable projection lens is set based on the lens parameter.
9. A projection method for a projection device, wherein: The projection device includes a camera unit, a sensing unit, a projection unit including a rotatable projection lens, a rotating shaft unit, and a processor, and the method includes: Acquire a user image through the camera unit; Acquiring a user distance from the user's face to the projection device by the sensing unit; Acquire user facial key points and user head posture from the user image, wherein the user head posture includes a pitch angle, a azimuth angle, and a roll angle of the user's head; Determine the user's facial coordinates and the projection position of the projection device based on the user's facial key points, the user's head posture and the user distance; Determining the projection posture and lens parameters of the rotatable projection lens based on the user face coordinates and the projection position; and The rotating shaft unit is controlled to rotate the rotatable projection lens to the determined projection posture, and the rotatable projection lens is set based on the determined lens parameters to perform projection.
10. The projection method according to claim 9, wherein: The determining of the user's facial coordinates and the projection position of the projection device based on the user's facial key points, the user's head posture and the user distance comprises: Obtaining a rotation angle of the camera unit when acquiring the user image; Determine the user's facial coordinates based on the rotation angle, the user's facial key points and the user distance; Determining a rotation matrix based on the user's head posture; The projection position is determined based on the rotation matrix and the user face coordinates.
11. The projection method according to claim 9, wherein: The rotating shaft unit includes an azimuth rotation shaft body and a pitch angle rotation shaft body. Wherein, controlling the rotating shaft unit to rotate the rotatable projection lens to the determined projection posture includes: The directional angle rotation axis and the pitch angle rotation axis are controlled to rotate the rotatable projection lens to the projection posture.
12. The projection method according to claim 11, wherein: The determining the projection posture and the lens parameters based on the user facial coordinates and the projection position includes: Based on the projection position, searching the stored lens parameters for the position closest to the projection position by a nearest neighbor search method; Performing an interpolation operation on the lens parameters of the position closest to the projection position found by a parameter interpolation method, and using the interpolation operation result as the lens parameter; Based on the projection position and the user face coordinates, calculating an alignment vector from the projection position to the user face coordinates; Based on the alignment vector, determining the azimuth rotation angle of the azimuth rotation axis and the pitch angle rotation angle of the pitch angle rotation axis; The azimuth rotation angle and the pitch rotation angle are used as the projection posture.
13. The projection method according to claim 9, wherein: The projection device further includes a moving unit, wherein the projection method further includes: sensing the position and movement speed of the user by the sensing unit; predicting at least one future location of the user based on the location and movement speed of the user; determining a predicted path of the projection device based on the at least one future position; The moving unit is controlled to drive the projection device to move based on the predicted path.
14. The projection method according to claim 9, wherein: The controlling the rotating shaft unit to rotate the rotatable projection lens to the determined projection posture, and setting the rotatable projection lens to perform projection based on the determined lens parameters, comprises: Determining a posture change rate of the projection posture based on the projection posture and the current projection posture of the rotating shaft unit; Based on the attitude change rate exceeding a first threshold, controlling the rotation axis unit to rotate the rotatable projection lens to the determined projection attitude; Determining a parameter change rate of the lens parameter based on the lens parameter and a current lens parameter of the rotating shaft unit; Based on the parameter change rate exceeding a second threshold, the rotatable projection lens is set based on the lens parameter.
15. A computer-readable storage medium storing a computer program, wherein: When the computer program is executed by a processor, the projection method for a projection device according to any one of claims 9 to 14 is implemented.
16. A computing device comprising: at least one processor; At least one memory stores a computer program, and when the computer program is executed by the at least one processor, the projection method for a projection device according to any one of claims 9 to 14 is implemented.