Desktop robot expression display method and system for circular double screens

Abstract

The invention discloses a desktop robot expression display method and system for circular double screens, and belongs to the technical field of intelligent interaction equipment display. According to the system, a main control unit, a circular double-screen module, a storage module and a double-screen driving module integrated with a double-screen buffer unit are adopted to construct a hardware architecture; the method comprises an expression file adaptation processing step, a standardized storage step, a double-eye dual-mode control step and a double-screen collaborative display step. The adaptive processing solves the problem of incomplete display through format conversion, resolution scaling and pixel cutting based on a circular physical contour; the double-screen buffering mechanism adopts a ping-pong buffering strategy of background frame drawing and foreground display to eliminate picture tearing; in the dual-mode control mechanism, the symmetric mode realizes single-side resource reuse through a horizontal flipping algorithm, and the independent mode supports binocular differential expression display. According to the invention, the integrity, fluency and adaptation efficiency of round double-screen expression display are remarkably improved, and the method is suitable for desktop accompanying robots and other intelligent interaction devices.

Description

Technical Field

[0001] This invention relates to the field of display technology for intelligent interactive devices, specifically to a method and system for displaying facial expressions on a desktop robot with a circular dual-screen display. Background Technology

[0002] With the rapid development of artificial intelligence technology, desktop companion robots are gradually entering home and office settings, becoming an important component of intelligent interactive devices. To enhance the friendliness and emotional expression of human-computer interaction, desktop companion robots generally adopt a dual-screen display scheme to simulate human eyes, achieving emotional interaction through facial expressions. Among them, circular dual screens, due to their visual friendliness and anthropomorphic characteristics, are gradually becoming the core expression display medium for this type of device.

[0003] Currently, the facial expression display technology of desktop companion robots is mainly based on GIF animation format, using pre-made facial expression animation files in conjunction with voice, touch, and other interactive scenarios. However, existing technology has the following technical shortcomings in the practical application of circular dual-screen facial expression display: First, existing solutions generally use the common GIF format as the emoji resource without specifically adapting it to the physical characteristics of circular dual-screen displays. Since common GIF files are typically designed with a square resolution, while the visible area of ​​a circular LCD screen is a circular outline, the four corners of the square image are obscured by the circular screen during actual display, resulting in incomplete emoji display and affecting the visual experience. Furthermore, the resolution of existing GIF files often does not match the 240×240 resolution of circular dual-screen displays, and the lack of targeted scaling and cropping further exacerbates the incomplete display problem.

[0004] Second, existing technologies lack buffering mechanisms for dual-screen displays. In high-frame-rate scenarios such as rapid blinking and continuous expression switching, screen tearing can easily occur due to the asynchronous transmission and display of frame data. This manifests as discontinuous or misaligned images in the upper and lower parts, severely affecting the smoothness of expression display and user experience.

[0005] Third, the dual-eye expression control method has limitations. Existing solutions either only support displaying identical expressions in both eyes, lacking the ability to differentiate expressions and failing to meet the needs of complex interaction scenarios (such as a playful expression requiring one eye to smile and the other to blink); or require designers to manually create separate GIF files for the left and right eyes, resulting in a cumbersome development process, high resource production costs, a large maintenance workload, and low adaptation efficiency.

[0006] Fourth, there are technical issues with the management and loading of emoji files. Current technology lacks a unified file naming convention and categorized storage strategy, resulting in inconsistent emoji file formats (some are GIF87a, some are GIF89a), leading to poor compatibility during device reading and decoding and a high risk of parsing errors. Furthermore, the disordered storage of emoji files on the storage medium, lacking optimized management based on usage frequency, results in high file loading latency and an inability to accurately synchronize with the duration of interactions such as voice replies and touch responses, impacting the overall continuity of the interactive experience. Summary of the Invention

[0007] The aforementioned technical defects have limited the application effect of the circular dual-screen expression display solution in desktop companion robots. There is an urgent need for a technical solution that can solve problems such as incomplete display, screen tearing, low adaptation efficiency, and high loading latency, so as to improve the smoothness, completeness, and adaptation flexibility of the circular dual-screen expression display.

[0008] Therefore, a method for displaying facial expressions on a desktop robot with a circular dual-screen layout is proposed, including the following steps: S1. The steps for adapting emoji files are as follows: S1.1 Obtain the original GIF emoticon file, check if the file format is GIF89a, and if not, convert it to GIF89a. S1.2 Scale the GIF file resolution to 240×240 pixels, consistent with the resolution of the circular dual-screen setup; S1.3 Based on the physical contour of the circular dual screen, perform circular cropping, retain the effective pixel area within the circular range, and crop redundant pixels at the four corners; the radius of the circular contour is 120 pixels, the center coordinates are (120, 120), and the cropping logic is: for a pixel (x, y), if (x-120)²+(y-120)²≤120², then retain the pixel; otherwise, crop it. S1.4 The clipped frame data is preprocessed using a dual-screen buffer, employing a mechanism of background frame drawing and foreground display; S2. The steps for storing emoji files are as follows: S2.1 Name the adapted GIF file according to the standardized naming rules. The naming format includes emotion type, display mode identifier, eye identifier, playback duration and speed coefficient. S2.2 Store the named files according to their mood type to the corresponding directory level on the SD card; S3, Dual-mode control steps for eye expressions, are as follows: S3.1 The main control unit receives instructions from the host computer and determines whether to use symmetrical display mode or independent display mode based on the instruction identifier or file name identifier; S3.2 If it is a symmetrical display mode, read the GIF file of the right eye from the SD card, run the horizontal flip algorithm to generate the left eye frame data, the formula of the horizontal flip algorithm is x_left=240-x_right, y_left=y_right; and send the original right eye frame data and the flipped left eye frame data to the dual-screen driver module simultaneously. S3.3 If it is an independent display mode, the right eye forward GIF file and the left eye flip GIF file are read from the SD card respectively, and the frame data of the two side files are sent to the two independent interfaces of the dual screen driver module respectively. S4, the dual-screen driver module synchronously outputs frame data to the left and right eye circular dual screens to realize expression display.

[0009] And a desktop robot facial expression display system for circular dual-screen displays, including: The main control unit uses an ESP32P4 chip or a microcontroller compatible with ESP32 and STM32 series microcontrollers to parse host computer instructions, call emoji files in SD card, run horizontal flipping algorithm and control dual-screen drive. The circular dual-screen module includes two circular LCD screens with a resolution of 240×240, corresponding to the robot's left and right eyes respectively; The SD card storage module has a capacity of no less than 8GB and is connected to the main control unit via a communication protocol. It is used to store the adapted GIF emoticon files and supports high-speed sector read and write. The LVGL+SPI dual-screen driver module integrates a dual-screen buffer unit and connects to the main control unit via a communication protocol with a communication rate of 10MHz. It is used for GIF decoding, frame data caching, and dual-screen synchronous output. The power module outputs a stable 5V voltage to provide power support for all modules. The SD card storage module adopts a hierarchical storage structure, including a root-level expression storage area, a first-level sub-level classified by emotion type, and a second-level sub-level containing dedicated files for symmetrical and independent modes.

[0010] In step S1.2, the resolution scaling uses a bilinear interpolation algorithm to ensure that the image is not distorted.

[0011] In step S2.1, the naming format of the symmetrical display mode file is: Emotion type_number 1_number 2s_x speed coefficient.gif; the naming format of the independent display mode file is: Emotion type_independent_eye_number 1_number 2s_x speed coefficient.gif; where number 1_number 2s represents the playback duration and x speed coefficient represents the playback speed adjustment factor.

[0012] For example, in the file "Happy_8_36s_x1.1.gif", "Happy" represents the emotion type, "8_36s" indicates the playback duration is 8.36 seconds (automatically calculated by the GIF_Tool), and "x1.1" represents the playback speed coefficient (1.1 times the duration, which can be flexibly adjusted according to the interactive scenario). The file format is required to be GIF89a version to support frame animation control, and the size of a single file must be controlled within 1MB. The naming format of the independent mode file is emotion type_independent_eye_number1_number2s_xspeed coefficient.gif, for example, "Happy_independent_left_6_1s_x0.9.gif", where "independent" indicates that the file is suitable for independent display mode, "left" indicates the left eye of the corresponding robot, and the meanings of the other parameters are the same as those of the symmetrical mode file. The left eye file is an adapted version after horizontal flipping. Storage optimization strategies include two aspects: high-frequency emoji storage and redundant file cleanup. High-frequency emoji storage involves storing frequently used emoji files, such as those for standby or happy expressions, in high-speed sectors of the SD card to ensure that loading latency does not exceed 40ms. Redundant file cleanup refers to the system periodically checking the file usage status and automatically cleaning up emoji files that have not been used for 30 days or more to free up storage space and ensure stable available capacity of the SD card.

[0013] Step S2.2 also includes a storage optimization strategy: storing frequently used emoji files in the high-speed sector of the SD card to ensure that the loading delay does not exceed 40ms; periodically checking the file usage status and automatically cleaning up emoji files that have not been used for a set threshold.

[0014] In step S3.2, in symmetrical display mode, only one right-eye GIF file needs to be read from the SD card, and the left-eye frame data is generated in real time through the horizontal flipping algorithm, without the need to pre-create the left-eye resource file.

[0015] In step S3.3, in the independent display mode, the playback duration and speed coefficient of the two GIF files can be set to be different to achieve differentiated expression display.

[0016] In step S4, the expression display effect meets the following indicators: no four-corner obstruction, no screen tearing, playback frame rate of not less than 30fps, loading delay of not more than 50ms, and dual-side playback synchronization rate of not less than 95% in independent display mode.

[0017] The dual-screen buffer unit of the LVGL+SPI dual-screen driver module adopts a dual-buffering mechanism of background frame drawing and foreground display to avoid screen tearing caused by asynchronous frame data transmission and display.

[0018] In the SD card storage module, the first-level sub-level is classified by emotion type, including: happy, angry, shy, and standby, which correspond to the robot's interactive scenarios such as voice response, touch response, and standby state.

[0019] The emoticon files must be in GIF89a format, and the size of a single file must be less than 1MB.

[0020] The main control unit is connected to the SD card storage module and the dual-screen driver module via the SPI communication protocol, forming a complete data stream transmission link of file reading, instruction processing, frame data output and display.

[0021] The dual-screen driver module provides real-time feedback of playback status information to the main control unit, including playback start, playback end, and error information, forming a control closed loop.

[0022] Compared with the prior art, the beneficial effects of the present invention are: This invention achieves precise matching between emoji resources and the physical characteristics of a circular dual-screen environment by forcibly converting to GIF89a format, accurately scaling to 240×240 resolution, and pixel-level cropping based on the circular physical outline. The cropping logic is based on the radius (120 pixels) of the circular screen and the center coordinates (120, 120), precisely removing redundant pixels at the four corners of the square GIF and retaining only the effective pixel area within the circular range.

[0023] This invention significantly improves the adaptation efficiency and scenario flexibility of binocular expression control. It innovatively proposes a dual-mode control mechanism for both eyes. In symmetrical display mode, a horizontal flipping algorithm (x_left=240-x_right, y_left=y_right) enables real-time reuse of GIF resources on one side, eliminating the need to pre-create a left-eye expression file. In independent display mode, independent driving interfaces on both sides support differentiated expression display for the left and right eyes, enabling complex expression combinations such as a right-eye smile and a left-eye blink, meeting the needs of complex interactive scenarios. This dual-mode mechanism balances adaptation efficiency and usage flexibility, overcoming the shortcomings of existing technologies with single display modes or redundant adaptation processes.

[0024] To ensure smooth display in high frame rate scenarios from a hardware perspective, this invention integrates a dual-screen buffer unit in the LVGL+SPI dual-screen driver module and adopts a ping-pong buffer mechanism of "background frame drawing + foreground display" to separate the drawing and display processes of frame data, thus avoiding screen tearing caused by asynchronous transmission and display.

[0025] This invention establishes standardized file naming rules (including key information such as emotion type, display mode identifier, playback duration, and speed coefficient) and a categorized storage strategy (establishing a multi-level directory structure according to emotion type), enabling the main control unit to quickly locate and parse emoticon files. Combined with optimized designs for high-frequency emoticon high-speed sector storage and automatic cleanup of redundant files, file read compatibility is significantly improved, reducing loading latency from over 300ms in existing technologies to less than 40ms (for high-frequency files). Simultaneously, the duration information embedded in the standardized naming facilitates accurate matching with interactive scenarios such as voice replies and touch responses, overcoming the shortcomings of existing technologies such as chaotic file formats and disordered storage leading to high latency and poor synchronization.

[0026] Furthermore, this invention provides a complete end-to-end technical solution, encompassing hardware architecture, standardized storage, intelligent adaptation processing, dual-mode control, and dual-screen collaborative display. On the hardware side, the architecture design, based on the ESP32P4 main control chip paired with the LVGL graphics library and SPI dual-screen driver, is compatible with ESP32 and STM32 series microcontrollers, offering excellent hardware scalability. On the methodological side, it covers a complete process including expression file adaptation processing, standardized storage management, dual-mode control, and collaborative display. It can be directly applied to the circular dual-screen expression display of desktop companion robots and can be extended to other application scenarios such as smart wearable devices and smart display terminals equipped with circular dual screens, demonstrating strong practicality.

[0027] In summary, this invention comprehensively solves the technical problems of existing circular dual-screen expression display technology, such as incomplete display, screen tearing, low adaptation efficiency, and high loading latency, through a collaborative design of hardware adaptation, standardized adaptation, dual-mode control, and storage optimization. It provides an efficient, smooth, and flexible expression display solution for desktop companion robots and other intelligent interactive devices, demonstrating significant technological advancements and application value. Attached Figure Description

[0028] Figure 1 This document presents a method and system for displaying facial expressions on a circular dual-screen desktop robot, along with a hardware architecture diagram of the facial expression display system. Figure 2 This is a schematic diagram of a method for displaying facial expressions on a circular dual-screen desktop robot and the SD card storage structure of the system. Figure 3 This document presents a method for displaying facial expressions on a circular dual-screen desktop robot and a flowchart illustrating the system's facial expression display adaptation process. Figure 4 This is a method and system for displaying facial expressions on a circular dual-screen desktop robot, along with a dual-mode control logic diagram for eye-to-eye facial expressions. Figure 5 This is a schematic diagram illustrating a method and system for displaying facial expressions on a circular dual-screen desktop robot, as well as a dual-mode display of facial expressions in both eyes. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used in these embodiments have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0031] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. Example

[0032] This embodiment provides a complete implementation process for desktop robot facial expression display based on a symmetrical display mode, used to realize the robot's eyes. This invention discloses a method and system for displaying facial expressions on a desktop robot with circular dual screens. The core of this method, through a full-link design including hardware architecture adaptation, standardized storage, intelligent adaptation processing, dual-mode control, and dual-screen collaborative display, solves the problems of incomplete facial expression display, screen tearing, low adaptation efficiency, and high loading latency in existing technologies. The following, in conjunction with the appendix... Figure 1-5 Detailed explanation of the specific implementation of the technical solution: System components: This system is an integrated architecture that combines hardware support, storage management, algorithm processing, and control execution. Its core components include the expression display system hardware, SD card storage module, adaptation processing module, and dual-mode control module. These components work together to achieve efficient expression display on a circular dual-screen display.

[0033] Facial Expression Display System Hardware Architecture: correspond Figure 1 (Hardware architecture diagram of the facial expression display system) The hardware architecture uses the ESP32P4 as the core control unit, constructing a closed data flow loop of storage-main control-driver-display. The composition, connection relationship and parameter design of each module are as follows: Regarding core modules and parameters, the main control unit uses the ESP32P4 chip, compatible with ESP32 and STM32 series microcontrollers. It is mainly responsible for parsing host computer instructions, calling emoticon files from the SD card, running the horizontal flipping algorithm, and controlling the dual-screen drive. The circular dual-screen module consists of two 240×240 resolution circular LCD screens, corresponding to the robot's left and right eyes respectively. The screen outline is circular, and the four corner areas are non-display areas, which need to be cropped for redundant pixels through subsequent adaptation processing. The SD card storage module has a capacity of no less than 8GB and establishes a connection with the main control unit through a specific communication protocol. It is used to store the adapted GIF emoticon files and supports high-speed sector read and write to improve loading speed. The LVGL+SPI dual-screen drive module integrates a dual-screen buffer unit and connects to the main control unit through a specified communication protocol with a communication rate of 10MHz. It is mainly responsible for GIF decoding, frame data caching, and dual-screen synchronous output, solving the screen tearing problem from a hardware perspective. The power module outputs a stable 5V voltage to provide power support for all modules and can switch between lithium batteries and adapters to adapt to the mobile use scenarios of desktop robots.

[0034] Regarding connectivity, the data link is indicated by a solid arrow. The SD card storage module connects to the main control unit via a communication protocol, and the main control unit then connects to the LVGL+SPI dual-screen driver module via the same communication protocol. Finally, the dual-screen driver module outputs frame data to the circular dual-screen module via this communication protocol, forming a complete data stream transmission of file reading, instruction processing, frame data output, and display. The power supply link is indicated by a dashed arrow. The power supply module connects to the main control unit, the circular dual-screen module, the SD card storage module, and the dual-screen driver module respectively, ensuring stable power supply and eliminating the risk of power outages when all modules work together.

[0035] SD card storage structure: correspond Figure 2(SD card storage structure diagram) As a standardized storage medium for emoji files, the SD card reduces file loading latency and improves adaptation efficiency through categorized storage, standardized naming, and optimized management. The specific structure is as follows: The storage hierarchy is divided into a root level, a first-level sub-level, and a second-level sub-level. The root level is the emoji storage area, a dedicated partition on the SD card, independent of other system files. The first-level sub-level is categorized by emoji emotion type, including happy, angry, shy, and standby types, corresponding to the robot's voice responses, touch responses, and standby states. The second-level sub-level contains specific emoji files. Each first-level sub-level contains two types of resources: files for symmetrical modes and files for independent modes. File naming follows standardized rules, specifically a combination of emotion type, (independent_eye), duration, speed coefficient, and the .gif format extension, ensuring the main control unit can automatically parse file attributes. The naming format for symmetrical mode files is emotion type_number1_number2s_xspeed coefficient.gif, for example, "Happy_8_36s_x1.1.gif", where "Happy" represents the emotion type, "8_36s" indicates the playback duration is 8.36 seconds (automatically calculated by GIF_Tool), and "x1.1" represents the playback speed coefficient (1.1 times the duration, which can be flexibly adjusted according to the interaction scenario). The file format is required to be GIF89a version to support frame animation control, and the size of a single file should be controlled within 1MB. The naming format for independent mode files is emotion type_independent_eye_number1_number2s_xspeed coefficient.gif, for example, "Happy_independent_left_6_1s_x0.9.gif", where "independent" indicates that the file is suitable for independent display mode, "left" indicates the corresponding robot's left eye, and the meanings of the other parameters are the same as those of the symmetrical mode files. The left eye file is an adapted version after horizontal flipping. Storage optimization strategies include two aspects: high-frequency emoji storage and redundant file cleanup. High-frequency emoji storage involves storing frequently used emoji files, such as those for standby or happy expressions, in high-speed sectors of the SD card to ensure that loading latency does not exceed 40ms. Redundant file cleanup refers to the system periodically checking the file usage status and automatically cleaning up emoji files that have not been used for 30 days or more to free up storage space and ensure stable available capacity of the SD card.

[0036] How to display emoticons: Based on the above system components, this method achieves efficient expression display on circular dual screens through three core steps: adaptation processing, dual-mode control, and collaborative display. The specific process is as follows: Emoji display adaptation process: Corresponding Figure 3 (Flowchart of GIF display adaptation process) For the original general GIF file (non-89a version, square resolution), a special GIF file that meets the requirements of circular dual-screen display is generated through standardized adaptation processing. The specific steps are as follows: First, input the original GIF file. The file format is not limited, but the resolution must be at least 240×240. Next, the format is checked to see if the original GIF file is version 89a (achieved by parsing the file header identifier). If not, the GIF_Tool is used to convert it to GIF89a (supporting frame animation duration control). If it is, proceed to the next step. Then, resolution scaling is performed, scaling the compliant GIF file to 240×240 pixels (consistent with the resolution of the circular dual-screen display). Bilinear interpolation is used during scaling to ensure no image distortion. Afterward, circular outline cropping is performed. Based on the physical outline of the circular dual-screen display (radius 120 pixels, center coordinates (120, 120)), redundant pixels at the four corners of the square GIF are cropped, retaining the effective pixel area within the circular range. The cropping logic is: for pixel (x, y), if (x-120)² + (y-120)² is satisfied... If the pixel size is ≤120², the pixel is retained; otherwise, it is cropped to ensure unobstructed display of the expression. After cropping, dual-screen buffer preprocessing is performed, storing frame data in the buffer unit of the dual-screen driver module. A mechanism of background frame drawing + foreground display is adopted to avoid screen tearing caused by asynchronous frame data transmission and display. Then, mode matching judgment is performed to determine whether the expression adopts a symmetrical display mode or an independent display mode according to the usage scenario requirements. If it is a symmetrical mode, only the right eye forward GIF file is retained (the left eye symmetrical file will be generated later through an algorithm). If it is an independent mode, a right eye forward GIF file and a left eye horizontally flipped GIF file are generated separately. Finally, the adapted GIF file is named according to the above standardized naming rules and stored in the sub-layer of the corresponding emotion type on the SD card, completing the entire adaptation process.

[0037] Dual-mode control process for eye expressions: correspond Figure 4(Dual-mode control logic diagram for eye expressions) After receiving instructions from the host computer (such as voice interaction instructions or touch event instructions), the main control unit calls the adapted GIF file in the SD card and realizes eye expression control through two modes: symmetric and independent. The specific process is as follows: First, the main control unit triggers mode switching by parsing the instruction identifier or file name identifier. The switching conditions include the symmetric mode or independent mode instruction issued by the host computer and whether the file name contains the identifier "independent_left / right". In symmetrical display mode, the main control unit reads the right-eye GIF file (e.g., "happy_8_36s_x1.1.gif", GIF89a version, 240×240 pixels, already circularly cropped) from the SD card via a communication protocol. Then, a horizontal flip algorithm is run to generate left-eye frame data based on the right-eye GIF's frame data. The algorithm logic is that the left-eye pixel horizontal coordinate equals 240 minus the right-eye pixel horizontal coordinate (mirror symmetry), while the vertical coordinate remains unchanged. The formula is x_left = 240 - x_right, y_left = y_right (where x_right and y_right are the pixel coordinates of the right-eye frame data). Next, the main control unit synchronously sends the original right-eye frame data and the flipped left-eye frame data to the synchronization interface of the LVGL+SPI dual-screen driver module via the communication protocol. The driver module calls the frame data from the buffer unit. Finally, the dual-screen driver module synchronously outputs the frame data to the left and right eye circular dual screens, achieving symmetrical expression display (e.g., synchronized smiling). This mode requires only one GIF file, eliminating the need to repeatedly create left-eye resources, thus improving development efficiency by 60%. In independent display mode, the main control unit reads independent GIF files from the SD card via a communication protocol, including a right-eye forward GIF (e.g., "happy_8_36s_x1.1.gif") and a left-eye flipped GIF (e.g., "happy_independent_left_6_1s_x0.9.gif"). Then, it assigns drive instructions to each of the two files, specifying the playback order and speed coefficient of the frame data for the right and left eyes. Next, it sends the frame data from both files to the independent interfaces of the LVGL+SPI dual-screen drive module, where the drive module independently decodes and buffers the frame data. Finally, the dual-screen drive module outputs the frame data to the left and right circular dual screens respectively, enabling differentiated eye expressions (e.g., a right-eye smile + a left-eye blink) to meet the needs of complex interactive scenarios. Throughout the control process, the dual-screen drive module provides real-time feedback on the playback status (e.g., playback start, playback end, and error information) to the main control unit, ensuring a closed-loop control system.

[0038] Dual-screen collaborative display and effects: like Figure 5As shown, a dual-screen buffering mechanism and synchronous drive control achieve smooth display of facial expressions: In symmetrical display mode, the left and right eyes display perfectly symmetrical expressions (such as both eyes smiling simultaneously), with no corner occlusion (occlusion rate of 0%), no screen tearing (tearing rate of 0%), a playback frame rate of no less than 30fps, and a loading latency of no more than 50ms; In independent display mode, the left and right eyes display differentiated expressions (such as the right eye smiling + the left eye blinking), with a bilateral playback synchronization rate of no less than 95%, and the speed coefficient can be adjusted as needed (e.g., x1.1 means the playback duration is extended by 1.1 times, x0.9 means the playback duration is shortened by 0.9 times), which can adapt to the duration requirements of different interaction scenarios such as voice reply and touch response. The dual-screen buffering mechanism solves the screen tearing problem in high frame rate scenarios, the circular cropping process solves the display incompleteness problem, and the standardized storage and naming rules control the loading latency to within 40ms, with a synchronization accuracy of no less than 90% with the interaction scenario duration.

[0039] In summary, the key technical features of this invention are reflected in four aspects: hardware adaptation, standardized adaptation, dual-mode control, and storage optimization. Hardware adaptation utilizes an ESP32P4 main control chip paired with an LVGL graphics library and an SPI dual-screen driver module. Combined with a 240×240 circular dual-screen architecture, it supports high-speed SPI communication (10MHz) and dual-screen buffering, providing hardware support for smooth display. Standardized adaptation, through a triple design of mandatory GIF89a format, 240×240 resolution scaling, and circular outline cropping, completely solves the problem of incomplete expression display. In dual-mode control, the symmetrical mode achieves single-sided resource reuse through a horizontal flipping algorithm, while the independent mode achieves differentiated display through independent dual-sided driving, balancing adaptation efficiency and usage flexibility. Storage optimization employs a combination of categorized storage, standardized naming, high-speed sector storage, and automatic cleanup of redundant files, effectively reducing loading latency and improving file management efficiency.

[0040] This embodiment verifies the technical feasibility of the symmetrical display mode. By using a single-sided resource and real-time flipping algorithm, the adaptation efficiency is significantly improved while ensuring display quality. It solves the defects of the prior art and can be directly applied to the circular dual-screen expression display of desktop companion robots. It also has strong adaptability, is compatible with ESP32 and STM32 series main control chips, and can be extended to other intelligent interactive devices equipped with circular dual screens.

Claims

1. A method for displaying facial expressions on a desktop robot with a circular dual-screen layout, characterized in that, Includes the following steps: S1. The steps for adapting emoji files are as follows: S1.1 Obtain the original GIF emoticon file, check if the file format is GIF89a, and if not, convert it to GIF89a. S1.2 Scale the resolution of the GIF file to match the resolution of the circular dual-screen display. The resolution scaling uses a bilinear interpolation algorithm. S1.3 Based on the physical contour of the circular dual screen, perform circular cropping, retain the effective pixel area within the circular range, and crop redundant pixels at the four corners; the radius of the circular contour is r pixels, the center coordinates are (120, 120), and the cropping logic is: for pixel (x0, y0), if (x-x0)²+(y-y0)²≤r², then retain the pixel; otherwise, crop it. S1.4 The clipped frame data is preprocessed using a dual-screen buffer, employing a mechanism of background frame drawing and foreground display; S2. The steps for storing emoji files are as follows: S2.1 Name the adapted GIF file according to the standardized naming rules. The naming format includes emotion type, display mode identifier, eye identifier, playback duration and speed coefficient. S2.2 Store the named files according to their mood type to the corresponding directory level on the SD card; S3, Dual-mode control steps for eye expressions, are as follows: S3.1 The main control unit receives instructions from the host computer and determines whether to use symmetrical display mode or independent display mode based on the instruction identifier or file name identifier; S3.2 If it is a symmetrical display mode, read the GIF file of the right eye from the SD card, run the horizontal flip algorithm to generate the left eye frame data, the formula of the horizontal flip algorithm is x_left=240-x_right, y_left=y_right; and send the original right eye frame data and the flipped left eye frame data to the dual-screen driver module simultaneously. S3.3 If it is an independent display mode, the right eye forward GIF file and the left eye flip GIF file are read from the SD card respectively, and the frame data of the two side files are sent to the two independent interfaces of the dual screen driver module respectively. S4, the dual-screen driver module synchronously outputs frame data to the left and right eye circular dual screens to realize expression display.

2. The method for displaying facial expressions on a desktop robot with a circular dual-screen display according to claim 1, characterized in that, Step S2.2 also includes a storage optimization strategy: storing frequently used emoticon files in the high-speed sector of the SD card; periodically checking the file usage status and automatically cleaning up emoticon files whose unused time reaches a set threshold.

3. The method for displaying facial expressions on a desktop robot with a circular dual-screen display according to claim 1, characterized in that, In step S3.2, the right eye GIF file is read from the SD card in symmetrical display mode, and the left eye frame data is generated in real time through a horizontal flipping algorithm.

4. The method for displaying facial expressions on a desktop robot with a circular dual-screen display according to claim 1, characterized in that, In step S3.3, different playback durations and speed coefficients are set for the two GIF files in independent display mode to achieve differentiated expression display.

5. A desktop robot facial expression display system for circular dual-screen displays, characterized in that, include: The main control unit uses an ESP32P4 chip or a microcontroller compatible with ESP32 and STM32 series microcontrollers to parse host computer instructions, call emoji files in SD card, run horizontal flipping algorithm and control dual-screen drive. The circular dual-screen module includes two LCD screens, corresponding to the robot's left and right eyes respectively; The SD card storage module connects to the main control unit via a communication protocol and is used to store adapted GIF emoticon files, supporting high-speed sector read and write. The LVGL+SPI dual-screen driver module integrates a dual-screen buffer unit and connects to the main control unit via a communication protocol with a communication rate of 10MHz. It is used for GIF decoding, frame data caching, and dual-screen synchronous output. The power module provides power support for all modules; The SD card storage module adopts a hierarchical storage structure, including a root-level expression storage area, a first-level sub-level classified by emotion type, and a second-level sub-level containing dedicated files for symmetrical and independent modes.

6. A desktop robot facial expression display system for a circular dual-screen setup according to claim 5, characterized in that, The dual-screen buffer unit of the LVGL+SPI dual-screen driver module adopts a dual-buffering mechanism of background frame drawing and foreground display to avoid screen tearing caused by asynchronous frame data transmission and display.

7. A desktop robot facial expression display system for a circular dual-screen setup according to claim 5, characterized in that, The main control unit is connected to the SD card storage module and the dual-screen driver module via the SPI communication protocol to form a data stream transmission link.

8. A desktop robot facial expression display system for a circular dual-screen setup according to claim 5, characterized in that, The dual-screen driving module feeds back playback status information to the main control unit in real time, including playback start, playback end, and abnormal information, forming a control closed loop.

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