A multi-joint active oral lamp based on a direct drive module and an intelligent control method thereof

Abstract

The present application relates to the technical field of oral cavity lamp, more particularly to a multi-joint active oral cavity lamp based on a direct drive module and an intelligent control method thereof. The oral cavity lamp comprises a stand; a rotating arm connected to the stand using a rotating arm module, the rotating arm module being capable of driving the rotating arm to rotate around a first vertical axis relative to the stand; a balance arm connected to the rotating arm using a balance arm module, the balance arm module being capable of driving the balance arm to rotate around a second vertical axis relative to the rotating arm, the balance arm having two movable segments, and the balance arm module being capable of changing the two movable segments of the balance arm to perform a pitching motion; a lamp head support connected to the balance arm using a lamp head support module, the lamp head support module being capable of driving the lamp head support to rotate around a third vertical axis relative to the balance arm; and a lamp head connected to the support using a lamp head module, the lamp head module being capable of driving the lamp head to rotate around a horizontal axis relative to the lamp head support.

Description

Technical Field

[0001] This invention relates to the field of dental lamp technology, and more specifically to a multi-joint active dental lamp based on a direct-drive module and its intelligent control method. Background Technology

[0002] In the field of oral healthcare, dental lamps, as key lighting devices in dental treatment units, provide essential visual support for various oral surgeries. Currently, the commonly used manual-adjustable dental lamps require dentists to frequently touch the lamp body or joint handle during operation to adjust the illumination angle and position of the lamp head. Although such traditional devices can meet basic lighting needs under routine surgical conditions, their inherent shortcomings are becoming increasingly prominent in practical applications, mainly in the following aspects:

[0003] First, there are issues with operational precision and the risk of patient discomfort: Doctors rely on experience and hand movements to adjust the lamp position, but manual operation is inherently subjective and prone to error, making precise control of the light direction difficult. If the light is misaligned and shines directly into the patient's eyes, it will cause significant discomfort and, in severe cases, even eye damage. Simultaneously, the complex structure of the oral cavity requires doctors to constantly adjust the lamp position to illuminate different areas, but manual adjustment makes it difficult to ensure uniform light distribution, leading to blind spots deep within the oral cavity, limiting the surgical field of vision, and affecting the accuracy of treatment. Especially in complex dental restorations or root canal treatments, doctors need to clearly observe the fine structures of the teeth and the lesion site; poor light angles or unstable lighting can lead to operational deviations, thus affecting the treatment outcome.

[0004] Secondly, frequent interruptions lead to low surgical efficiency: During treatment, doctors often need to pause their instruments to adjust the lighting, each adjustment taking about half a minute, and multiple adjustments are often required in a single surgery. These frequent interruptions not only prolong the overall surgical time and increase its complexity but also disrupt the doctor's rhythm, reducing diagnostic and treatment efficiency. In a day's outpatient work, if multiple patients receive treatment, the accumulated lighting adjustment time will consume a significant portion of the surgical time, indirectly increasing medical costs, while also prolonging patient waiting times and reducing the overall patient experience.

[0005] Third, there is a risk of cross-infection: During the procedure, the doctor's hands frequently touch the light adjustment devices, and pathogens from the patient's saliva and blood can easily adhere to the surface of the equipment. When the doctor touches these adjustment devices again, they may transmit pathogens to the next patient, causing cross-infection. Given the increasing awareness of public health, this issue has become a significant concern in the field of oral healthcare, especially in areas with high rates of infectious diseases, where the hygiene and safety of dental equipment are particularly crucial.

[0006] To address this, existing solutions have attempted to integrate electric modules into the joints of dental lamps. However, current electric solutions mostly employ general-purpose robotic joint modules consisting of motors, reducers, and encoders, which suffer from drawbacks such as large size, high rotational inertia, significant inertial shock during adjustments, and high cost. More importantly, these existing electric joint dental lamp solutions lack corresponding intelligent control schemes. For example, patients are not always in a stable treatment state during dental treatment but experience various states, such as lying down for preparation, opening their mouth for treatment, closing their mouth to rest, getting up to rinse their mouth, and leaving the dental chair. If the dental lamp relies solely on visual images for facial or oral cavity tracking, it may continue to follow the patient's face or mistakenly follow other targets in the image when the patient is resting, getting up, rinsing their mouth, or leaving the dental chair, causing unnecessary movement of the lamp head and affecting the user experience. Existing control schemes do not consider these practical application scenarios and lack practical applicability. Summary of the Invention

[0007] This invention provides a multi-joint active oral lamp based on a direct-drive module and its intelligent control method, the purpose of which is to enable...

[0008] The above objectives are achieved through the following technical solutions:

[0009] A multi-joint active oral lamp, comprising:

[0010] A column, a rotating arm, and a rotating arm module connected between the column and the rotating arm are used to drive the rotating arm to rotate relative to the column about a first vertical axis.

[0011] A balance arm, and a balance arm module connected between the rotating arm and the balance arm, for driving the balance arm to rotate relative to the rotating arm about a second vertical axis, and for driving the balance arm to perform pitch motion;

[0012] Lamp head bracket, and lamp head bracket module connected between the balance arm and the lamp head bracket, for driving the lamp head bracket to rotate relative to the balance arm about a third vertical axis;

[0013] The lamp head, and the lamp head module connected between the lamp head bracket and the lamp head, are used to drive the lamp head to rotate about a horizontal axis relative to the lamp head bracket.

[0014] Among them, the rotating arm module, the balance arm module, and the lamp head bracket module all include a drive motor integrated in the corresponding module housing. The rotational motion of the drive motor is transmitted to the corresponding rotating arm, balance arm, or lamp head bracket through the module housing.

[0015] The aforementioned rotating arm module includes a lower outer shell of the rotating arm module connected to the column, an upper outer shell of the rotating arm module connected to the rotating arm, and a rotating arm module bushing disposed between the lower outer shell and the upper outer shell of the aforementioned rotating arm module. The aforementioned rotating arm module bushing and the aforementioned upper outer shell of the rotating arm module form a clearance fit to generate an oil film during operation.

[0016] The mentioned rotating arm module also includes a rotating arm module rotating shaft, the axis of which is perpendicular to the axis of the flange shaft that transmits the torque of the drive motor in the mentioned rotating arm module, so as to provide radial support when the upper housing of the mentioned rotating arm module rotates.

[0017] The stabilizer arm module mentioned above includes a four-bar linkage, which is driven by the stabilizing module's lifting motor, enabling the stabilizer arm to perform pitching motion.

[0018] A control method for a multi-joint active oral lamp, used to control the aforementioned multi-joint active oral lamp, comprising:

[0019] Acquire patient-related signals collected by the acquisition module;

[0020] Based on the comparison results between the mentioned patient-related signals and the preset conditions, the current working mode of the mentioned multi-joint active oral lamp is determined;

[0021] In the working mode that allows following illumination, at least some of the modules mentioned, such as the rotating arm module, the balancing arm module, the lamp head support module, and the lamp head module, are driven to move based on the position information of the oral cavity target area, so that the illumination optical axis of the lamp head is aligned with the oral cavity target area.

[0022] The mentioned acquisition module includes a camera installed on the mentioned lamp head, and the mentioned patient-related signals include images of the oral cavity region acquired by the mentioned camera; the mentioned method of driving the movement of each module based on the position information of the oral cavity target region includes: extracting the spatial angle deviation of the target irradiation area from the mentioned oral cavity region image, calculating the driving increment of each module through inverse kinematics based on the mentioned spatial angle deviation and the current joint angle value fed back by the encoder of each joint module, and driving the movement of the corresponding module based on the mentioned driving increment.

[0023] The mentioned acquisition module also includes a pressure detection unit and a distance detection unit. The pressure detection unit is configured to acquire the patient's postural pressure signal on the dental chair, and the distance detection unit is configured to acquire the distance information from the lamp head to the patient's face. The method of determining the current working mode based on the comparison results of the patient-related signals and preset conditions includes: determining the current working mode based on at least two of the mentioned postural pressure signal, the mentioned distance information, and the mentioned face recognition results of the camera. The mentioned working modes include at least two of the following modes: oral cavity following illumination mode, ready state mode, yielding mode, and standby mode.

[0024] During the operation of the oral cavity following illumination mode, if the target area of ​​the oral cavity cannot be identified due to occlusion in the image captured by the camera, the current illumination position of the lamp head will be maintained if the number of consecutive occlusion frames does not exceed the preset occlusion frame threshold; otherwise, the oral cavity following illumination mode will be exited.

[0025] After completing the movement of each module, the process also includes: acquiring the illuminance value of the target area collected by the illuminance sensor installed around the lamp head; based on the comparison result between the illuminance value and the preset minimum illuminance threshold, if the illuminance value is lower than the preset minimum illuminance threshold, triggering compensation movement; and adjusting the preset minimum illuminance threshold based on the statistics of the number of illuminance compensation triggers within the preset evaluation window.

[0026] The beneficial effects of this invention, a multi-joint active oral lamp based on a direct-drive module and its intelligent control method, are as follows:

[0027] By acquiring real-time images of the target area of ​​the oral cavity through a camera mounted on the lamp head, and combining the angle values ​​fed back by the encoders of each joint to calculate the driving increment in an inverse kinematics manner, autonomous lighting positioning that actively follows the target area of ​​the oral cavity through multiple joints is realized. This eliminates the need for the surgeon to manually and repeatedly adjust the position of the lamp head during the treatment process, thus keeping the surgeon's hands within the surgical operation area at all times and significantly reducing the surgical interruption time caused by lamp position adjustment.

[0028] By placing illuminance sensors around the lamp head and verifying the actual illuminance of the target area after joint adjustment, a closed loop of lighting quality is formed, encompassing pose adjustment, illuminance verification, and motion compensation. This is fundamentally different from an open-loop scheme that only uses pose alignment as the termination condition. It is understandable that blood seepage from oral tissues, saliva coverage, and differences in reflectivity of different tooth surfaces can all cause illuminance to be lower than the required level for treatment even under optical axis geometric alignment. The aforementioned illuminance verification closed loop ensures the reliability of the lighting effect in a real oral environment, rather than merely guaranteeing geometric positional certainty.

[0029] By accumulating statistics on the number of illumination compensation triggers and overshoot events, the minimum illumination threshold and alignment accuracy threshold are adaptively converged in the downward adjustment direction. The long-term operation of the system is a process in which the two thresholds gradually approach the optimal values ​​for specific equipment and specific operator groups in the clinic. Users do not need to preset accurate thresholds during the installation and commissioning phase, which reduces the cost of parameter tuning per unit when deploying the system in different clinics. At the same time, the system's spot alignment accuracy and illumination performance spontaneously improve with the number of uses during long-term use.

[0030] By periodically collecting patient positional pressure signals on the dental chair, distance information from the lamp head to the patient's face, and visual recognition results from the camera, and using a multi-dimensional signal joint judgment method to classify the patient's state into multiple mutually exclusive movement patterns, a safe binding between the lamp arm movement logic and the patient's actual state is achieved. This design addresses a key pain point: existing dental lamps often rely on a single distance sensor or proximity switch to determine the patient's position, leading to misjudgments when the dentist's hand or instruments obscure the sensor area. The multi-dimensional signal joint judgment method in this application, especially the cross-validation of visual recognition and pressure sensing results, allows the system to adopt a safety-first conservative strategy when faced with conflicting signals from a single sensor. This restricts the lamp arm from performing unintended following movements when no one is in position, fundamentally avoiding the risk of lamp head collisions caused by sensor misjudgments.

[0031] By introducing a brief occlusion retention logic and using the number of consecutive occlusion frames as the trigger condition for exiting follow mode, the problem of unnecessary retreat when surgical instruments or the surgeon's hand briefly pass through the camera's field of view, causing a temporary loss of the oral target, is solved. The lamp arm can resume illumination without repositioning after the occlusion is removed, avoiding interruptions in surgical area illumination and mechanical wear from the reciprocating motion of the lamp arm caused by frequent retreating and resetting. This maintains the continuity and stability of illumination in areas with dense instrument handling.

[0032] Meanwhile, in the design of the multi-joint drive mechanism, by integrating the drive motor inside the housing of each module and using the housing itself as the torque transmission component, the independent transmission box or coupling assembly in the traditional solution is eliminated. This allows the multi-joint active dental lamp to maintain the same external size and installation space requirements as the traditional passive suspended arm dental lamp while having five degrees of freedom of autonomous motion. This is beneficial for direct replacement and installation in existing dental clinics without the need to modify the clinic layout. Attached Figure Description

[0033] Figure 1 This shows an overall view of a multi-joint active oral lamp according to the present invention;

[0034] Figure 2 A schematic diagram of the rotating arm module is shown.

[0035] Figure 3 A schematic diagram of the counterweight arm module is shown.

[0036] Figure 4 A schematic diagram of the lamp holder module is shown.

[0037] Figure 5 A schematic diagram of the lamp head module is shown;

[0038] Figure 6 A flowchart of a multi-joint active oral lamp intelligent control method is shown.

[0039] In the diagram: 101, Column; 102, Rotating Arm; 103, Balance Arm; 104, Lamp Holder Bracket; 105, Lamp Holder; 201, Lower Housing of Rotating Arm Module; 202, Rotating Arm Module Bushing; 203, Rotating Arm Module Motor; 204, Rotating Arm Module Flange Shaft; 205, Upper Housing of Rotating Arm Module; 207, Rotating Arm Module Rotating Shaft; 301, Upper Housing of Balance Arm Module; 302, Balance Arm Module Bushing; 303, Balance Arm Module Connecting Housing; 304, Balance Arm Module Rotary Motor; 305, Balance Arm Module Auxiliary Bushing; 306, Balance Arm Module Flange Shaft; 307, Balance Arm Module Rotating Shaft; 3 08. Lower housing of the balance arm module; 309. Lifting motor of the balance arm module; 310. Crank of the balance arm module; 311. Connecting rod of the balance arm module; 401. Upper housing of the lamp holder bracket module; 402. Bushing of the lamp holder bracket module; 403. Connecting housing of the lamp holder bracket module; 404. Motor of the lamp holder bracket module; 405. Auxiliary bushing of the lamp holder bracket module; 406. Flange shaft of the lamp holder bracket module; 407. Rotating shaft of the lamp holder bracket module; 408. Lower housing of the lamp holder bracket module; 501. Motor of the lamp holder module; 502. Flange shaft of the lamp holder module; 503. Connecting housing of the lamp holder module; 504. Motor fixing component of the lamp holder module. Detailed Implementation

[0040] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0041] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0042] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate the direction or positional relationship, are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element mentioned must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0043] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0044] A multi-joint active oral lamp based on a direct drive module includes a longitudinally extending column 101 and a rotating arm module connected to the column 101.

[0045] The rotating arm module includes a lower outer shell 201, a rotating arm module motor 203 connected inside the lower outer shell 201, a rotating arm module flange shaft 204 connected to the output surface of the rotating arm module motor 203, a rotating arm module rotating shaft 207 connected to the upper part of the rotating arm module flange shaft 204, an upper outer shell 205 connected to the rotating arm module rotating shaft 207, and a rotating arm module bushing 202 disposed between the upper outer shell 205 and the lower outer shell 201. The upper outer shell 205 is located inside the lower outer shell 201, and the rotating arm module bushing 202 is connected to the lower outer shell 201. The rotating arm module bushing 202 and the upper outer shell 205 are clearance-fitted to form an oil film, which is used to reduce friction and wear. The axis of the rotating arm module's rotating shaft 207 is perpendicular to the axis of the rotating arm module's flange shaft 204, which is used to increase the stability of the upper housing 205 of the rotating arm module when it rotates.

[0046] The upper end of the upper housing 205 of the rotating arm module is connected to a laterally extending rotating arm 102. When the rotating arm module motor 203 is started, it drives the rotating arm module flange shaft 204 to rotate. The rotating arm module flange shaft 204 drives the rotating arm module rotating shaft 207 to rotate around the axis of the rotating arm module flange shaft 204. The rotating arm module rotating shaft 207 drives the upper housing 205 of the rotating arm module to rotate around the axis of the rotating arm module flange shaft 204. The upper housing 205 of the rotating arm module drives the rotating arm 102 to rotate relative to the column 101.

[0047] A balance arm module is installed on the rotating arm 102.

[0048] The balance arm module includes an upper housing 301 connected to the end of the rotating arm 102 away from the rotating arm module, a balance arm module bushing 302 and an auxiliary balance arm module bushing 305 connected to the outer wall of the upper housing 301, a balance arm module rotary motor 304 connected inside the upper housing 301, a balance arm module flange shaft 306 connected to the output surface of the rotary motor 304, and a balance arm module rotating shaft 307 connected to the flange shaft 306. The lower housing 308 of the balance arm module is connected to the rotating shaft 307 of the balance arm module. The lower housing 308 of the balance arm module is connected to the connecting housing 303 of the balance arm module. The bushing 302 and the auxiliary bushing 305 of the balance arm module are both clearance-fitted with the connecting housing 303 of the balance arm module to form an oil film, which reduces friction and wear. The bushing 302 of the balance arm module is located on the upper side of the connecting housing 303 of the balance arm module, and the auxiliary bushing 305 of the balance arm module is located on the lower side of the connecting housing 303 of the balance arm module.

[0049] To further explain, the balance arm 103 has a two-section structure, including a first arm body and a second wall body hinged to the first arm body. The lower end of the lower housing 308 of the balance arm module is connected to the first arm body. A balance arm module lifting motor 309 is connected to the balance arm module connecting housing 303. A balance arm module crank 310 is connected to the output surface of the balance arm module lifting motor 309. One end of the balance arm module connecting rod 311 is rotatably connected to the balance arm module crank 310. The other end of the balance arm module connecting rod 311 is rotatably connected to the second wall body to form a four-bar linkage.

[0050] When the balance arm module rotary motor 304 starts, it drives the balance arm module flange shaft 306 to rotate, which in turn drives the balance arm module rotating shaft 307 to rotate, further driving the balance arm module connecting housing 303 to rotate. This allows relative rotation between the lower housing 308 and the upper housing 301 of the balance arm module, enabling the balance arm 103 to rotate horizontally relative to the rotating arm 102. When the balance arm module lifting motor 309 starts, it drives the balance arm module crank 310 and the balance arm module connecting rod 311 to move, thereby enabling the balance arm 103 to achieve a pitch function.

[0051] A lamp holder module is installed on the balance arm 103.

[0052] The lamp holder module includes an upper housing 401 connected to the end of the balance arm 103 away from the balance arm module, a lamp holder module bushing 402 and an auxiliary bushing 405 connected to the outer wall of the upper housing 401, a lamp holder module connecting housing 403 fitted onto the upper housing 401, a lamp holder module motor 404 connected inside the upper housing 401, and a motor connected to the output surface of the lamp holder module motor 404. The lamp head bracket module has a flange shaft 406, a rotating shaft 407 connected to the flange shaft 406, a lower housing 408 connected to the rotating shaft 407, and a connecting housing 403. The lower housing 408 is connected to the connecting housing 403. The lamp head bracket module bushing 402 and the auxiliary bushing 405 are both clearance-fitted with the inner wall of the connecting housing 403 to form an oil film, which reduces friction and wear.

[0053] The lower end of the lower housing 408 of the lamp holder module is fixedly connected to the lamp holder bracket 104. When the lamp holder module motor 404 starts, it drives the lamp holder module flange shaft 406 to rotate. The lamp holder module flange shaft 406 drives the lamp holder module rotating shaft 407 to rotate around the axis of the lamp holder module flange shaft 406. The lamp holder module rotating shaft 407 drives the lamp holder module connecting housing 403 to rotate around the axis of the lamp holder module flange shaft 406. This allows the lower housing 408 of the lamp holder module to rotate relative to the upper housing 401 of the lamp holder module, and enables the lamp holder bracket 104 to rotate horizontally relative to the balance arm 103.

[0054] A lamp head module is installed on the lamp head bracket 104.

[0055] The lamp head module includes a lamp head module connecting housing 503 connected to a lamp head bracket 104, a lamp head module motor 501 connected to the lamp head module connecting housing 503, a lamp head module flange shaft 502 connected to the output surface of the lamp head module motor 501, a lamp head module connecting housing 503 connected to the lamp head module flange shaft 502, a lamp head module motor fixing member 504 connected to the lamp head module connecting housing 503, and a lamp head 105 connected to the lamp head module motor fixing member 504.

[0056] The aforementioned rotating arm module, balance arm module, and lamp head bracket module all operate on the same principle of horizontal rotation drive. They all achieve transmission by aligning the output shaft of a motor with the axis of a flange-like structure, thus driving the outer shell structure, which acts as the transmission component. Finally, the movement of the outer shell structure is transmitted to the next arm segment. Therefore, their structures are similar; the main differences lie in the number of bushing-like parts and whether a four-bar linkage is added. The lamp head module operates on the same principle, with its horizontal axis enabling vertical rotation drive.

[0057] The axis of the lamp head module motor 501 is horizontal. When the lamp head module motor 501 is started, it drives the lamp head module flange shaft 502 to rotate around the axis of the lamp head module motor 501. The lamp head module motor fixing part 504 drives the lamp head 105 to rotate around the axis of the lamp head module motor 501, thereby causing the lamp head 105 to rotate relative to the lamp head bracket 104.

[0058] In some embodiments, the aforementioned multi-joint active oral lamp further includes a control module and a camera 601 installed on the lamp head. The control module includes a target recognition module, a posture calculation module, a multi-joint drive module, an illuminance verification module, and a control strategy evolution module connected in sequence to achieve intelligent control.

[0059] Specifically, the target recognition module receives images of the oral cavity region captured by a camera 601 mounted on the lamp head, and extracts the center point coordinates Pc of the target illumination area from the image, as well as the positional offsets Δx and Δy of the center point coordinates Pc relative to the current optical axis of the lamp head. The positional offsets Δx and Δy represent the pixel distances of the target illumination area's center point from the image center in the horizontal and vertical directions within the camera 601's image coordinate system, respectively, and are converted into spatial angular deviations θ_x and θ_y via a calibration matrix, in degrees (°). The image acquisition frequency of the camera 601 is no less than 10 frames per second to ensure real-time tracking response of the target area.

[0060] The extraction method for the center point coordinates Pc of the target illumination area is not limited. It can be considered that before the treatment begins, the surgeon aligns the illumination spot of the lamp (105) with the tooth or tooth position area to be operated on, triggering a reference image acquisition. The target recognition module records the hue-saturation distribution characteristics of the area covered by the light spot in the reference image as a visual template for the current target area. During the treatment, the target recognition module performs histogram back projection of the hue-saturation space histogram on the oral cavity area images acquired frame by frame by the camera (601). It searches for the pixel connected region with the highest similarity to the visual template in the back projection response map, using the geometric center of this connected region as the center point coordinates Pc of the target illumination area in the current frame, and using the average hue deviation and saturation deviation of this connected region as matching reliability indicators. No specific limitations are made here; those skilled in the art can also use feature point matching based on pre-calibrated tooth position key points or region prediction based on arch curve fitting to extract the target illumination area.

[0061] Based on this, the attitude calculation module, using the mentioned spatial angle deviations θ_x and θ_y, and combining the current joint angle values ​​fed back by the encoders of each joint, calculates the required motor drive increments for each joint to align the lamp head optical axis with the center point of the target illumination area using inverse kinematics. This yields the drive increments Δq1 for the rotating arm module motor, Δq2 for the balancing arm module rotary motor, Δq3 for the balancing arm module lifting motor, Δq4 for the lamp head bracket module motor, and Δq5 for the lamp head module motor. The inverse kinematics solution uses the current angles of each joint as initial values ​​and aims for θ_x and θ_y to simultaneously approach zero as the convergence target. The combined deviation angle ΔΘ = √(θ_x² + θ_y²), in degrees, characterizes the overall angular deviation between the lamp head optical axis and the target center point for subsequent comparison with a preset threshold.

[0062] The mentioned multi-joint drive module, based on the drive increments of each joint output by the mentioned attitude calculation module, sends the drive increments Δq1 to Δq5 to the rotating arm module motor, the balance arm module rotary motor, the balance arm module lifting motor, the lamp head bracket module motor, and the lamp head module motor, respectively, so that the above motors sequentially complete the rotation of the corresponding drive amount, thereby enabling the lamp head to autonomously adjust to the pose aligned with the center point of the target illumination area.

[0063] During multi-joint coordinated motion, the encoders of each joint collect joint angle values ​​in real time and feed them back to the aforementioned posture calculation module for closed-loop correction until the aforementioned merged deviation angle ΔΘ is lower than the preset alignment completion threshold θ_done. The aforementioned alignment completion threshold θ_done ranges from 0.5° to 3°. In this embodiment, θ_done is set to 1.5°. This value is based on user evaluation of the light position deviation tolerance of at least 8 to 12 dentists in typical treatment scenarios. In some embodiments, 12 dentists are selected. The 1.5° deviation corresponds to a lamp head spot center offset of approximately 1.3cm at a working distance of 50cm, which meets the lighting accuracy requirements of 92% of the evaluated dentists.

[0064] The mentioned illuminance verification module is used to acquire the illuminance value E of the target irradiation area collected by the illuminance sensor installed on the periphery of the lamp head 105 after the mentioned multi-joint drive module completes one joint adjustment. The module then compares the illuminance value E with a preset minimum illuminance threshold E_min, and determines whether the illuminance under the current lamp head pose meets the diagnostic and treatment requirements based on the comparison result. The minimum illuminance threshold E_min ranges from 8000 lx to 20000 lx. In this embodiment, E_min is set to 15000 lx. This value is based on the national standard GB11604, which requires a minimum illuminance of not less than 10000 lx for oral examination lighting. A 20% margin is added to accommodate actual illuminance attenuation under different oral cavity depths and tissue reflectivities, but it is not limited to this. If the mentioned illuminance value E is not lower than E_min, the current lamp head posture remains unchanged, and the irradiation position adjustment is considered complete. If the mentioned illuminance value E is lower than E_min, the mentioned posture calculation module is triggered to superimpose a compensation forward movement amount Δd_z along the lamp head optical axis on the current posture, and the driving increment is recalculated. The compensation forward movement amount Δd_z ranges from 1.0cm to 5.0cm. In this embodiment, Δd_z is set to 2.0cm. This value is based on the following: under the condition that the typical oral treatment working distance D_work is 40cm to 60cm, based on the approximate relationship that the illuminance of a point light source is inversely proportional to the square of the distance E∝1 / D², each forward movement of 2.0cm can increase the illuminance by about 8% to 12%. It can gradually approach the illuminance target posture with a small single step size without excessively intruding into the patient's oral cavity safety space, but it is not limited to this. The illuminance verification module acquires the illuminance value E again after each compensation movement and compares it with E_min. This compensation process is repeated until E is not lower than E_min, or the cumulative number of compensation steps reaches the preset upper limit N_comp_max, at which point compensation terminates. N_comp_max ranges from 3 to 8 times; in this embodiment, it is set to 5 times, corresponding to a maximum total forward movement of 10.0 cm, which does not exceed the shortest safe warning distance d_min from the lamp head (105) to the patient's face. Therefore, when illuminance compensation cannot converge to above E_min, compensation is abandoned, and the posture after the last compensation is maintained, while a prompt signal is sent to the surgeon. The drive increment is recalculated to shorten the working distance, increase illuminance, and trigger the aforementioned multi-joint drive module to perform the compensation movement again. It is understood that the illuminance verification here forms a practical effect verification of the multi-joint movement results, ensuring that the control loop does not terminate at the completion of the movement, but rather at the attainment of the illuminance standard. This avoids situations where the movement accuracy is sufficient but the illuminance is insufficient due to occlusion, reflectivity differences, or working distance deviations.

[0065] During the continuous operation of the mentioned control module, the mentioned control strategy evolution module counts the number of illuminance compensation motions triggered N_comp and the number of overshoots N_over where the alignment completion threshold θ_done is still not reached after joint adjustment within a preset historical evaluation window T_eval, compares the mentioned N_comp and N_over with the preset compensation trigger rate threshold R_c and overshoot rate threshold R_o respectively, and adaptively adjusts the mentioned alignment completion threshold θ_done and the minimum illuminance threshold E_min based on the comparison results. Wherein, the value range of the historical evaluation window T_eval is 50 to 200 complete positioning operations. In this embodiment, T_eval is set to 100 times. The basis for this value is that in typical oral diagnosis and treatment, an average of 6 to 8 light position adjustments are required per visit, and 100 times cover approximately 12 to 16 visits, which can cover the comprehensive influence of different operators' operating habits and patient position differences on system performance. The compensation trigger rate R_c=N_comp / T_eval, and the overshoot rate R_o=N_over / T_eval.

[0066] The mentioned compensation trigger rate R_c is compared with the preset first ratio threshold R_c1 and the second ratio threshold R_c2, wherein the value range of the first ratio threshold R_c1 is 0.10 to 0.20, the value range of the second ratio threshold R_c2 is 0.25 to 0.40, and R_c1 < R_c2; in this embodiment, R_c1 is set to 0.15 and R_c2 is set to 0.30. The basis for this value is that based on the statistics of 30 light positioning tests in different scenarios, under normal service conditions, the illuminance compensation trigger rate is concentrated between 0.10 and 0.20, and exceeding 0.30 indicates that the illuminance margin of the lamp head is insufficient at the typical working distance. If R_c is lower than R_c1, E_min remains unchanged; if R_c is between R_c1 and R_c2, E_min is lowered by a preset first adjustment step ΔE1, so as to appropriately relax the illuminance requirement and reduce frequent compensation motions caused by slight position errors, wherein the value range of ΔE1 is 500lx to 1500lx, and ΔE1 is set to 800lx in this embodiment; if R_c is not lower than R_c2, it indicates that the current setting of E_min is too high and leads to excessively frequent compensation motions, and E_min is lowered by a preset second adjustment step ΔE2, wherein ΔE2 > ΔE1, the value range of ΔE2 is 1500lx to 3000lx, ΔE2 is set to 2000lx in this embodiment, and the lowered E_min shall not be lower than 8000lx to ensure the basic diagnosis and treatment lighting requirement. It should be noted that the adjustment direction of E_min is only downward, and there is no upward adjustment path, which is consistent with the goal that with the long-term use of the system in a specific clinic environment, the accumulated illuminance compensation experience enables the system to gradually converge to a more appropriate illuminance reference.

[0067] Simultaneously, the mentioned overshoot rate R_o is compared with a preset overshoot rate threshold R_o1, where R_o1 ranges from 0.05 to 0.15, and in this embodiment, R_o1 is set to 0.10. If R_o is not lower than R_o1, the mentioned alignment completion threshold θ_done is lowered by a preset angle adjustment step Δθ, where Δθ ranges from 0.1° to 0.5°, and in this embodiment, Δθ is set to 0.2°. The lowered θ_done must not be lower than 0.5° to prevent excessively high alignment accuracy requirements from causing the system to repeatedly adjust under slight jitter conditions. It is understood that lowering θ_done allows joint co-motion to converge with higher precision, thereby reducing overshoot problems caused by coarse alignment in subsequent operations and allowing the system sensitivity to adaptively tighten towards higher precision.

[0068] In some embodiments, the aforementioned multi-joint active oral lamp further includes a patient state perception module and a motion mode management module. The aforementioned patient state perception module and motion mode management module work together with the aforementioned control module to realize the perception and recognition of different patient states and the adaptive switching of lamp arm motion modes.

[0069] Specifically, the mentioned patient status perception module includes a patient posture detection unit and a target area availability judgment unit. The patient posture detection unit periodically collects the following sensor signals: the headrest pressure value Ph output by the headrest pressure sensor installed at the dental chair headrest; the back pressure value Pb output by the back pressure sensor installed at the dental chair backrest; the seat pressure value Ps output by the seat pressure sensor installed at the dental chair seat; and the distance d from the lamp head to the patient's face output by the distance sensor installed on the lamp head 105. The distance sensor can be implemented using infrared ranging, ultrasonic ranging, time-of-flight (TOF) ranging, or visual ranging. This embodiment uses TOF ranging, with an effective ranging range of 0.2m to 1.5m and a measurement frequency of not less than 10Hz. The target area availability judgment unit determines whether the face area appears stably and whether the oral cavity target point can be stably recognized by the image captured by the camera 601, and periodically outputs the face recognition status flag F_face and the oral cavity target recognition status flag F_oral; wherein, the value of F_face is valid or invalid, and the value of F_oral is stable, unstable or occluded.

[0070] Based on this, the mentioned motion mode management module, using the Ph, Pb, Ps, and d output by the mentioned patient posture detection unit and the F_face and F_oral output by the mentioned target area availability judgment unit, classifies the patient's state into four categories and switches the motion mode of the lamp arm accordingly. The preset thresholds for headrest pressure (P_th), back pressure (P_tb), and seat pressure (P_ts) are all calibrated through actual measurements of adults of different body types in standard dental chair postures. The effective working distance range from the lamp head to the patient's face, d_min to d_max, ranges from 0.3m to 1.0m. In this embodiment, d_min is set to 0.35m and d_max to 0.8m, based on statistical measurements of working distances in 20 typical oral surgeries, where 95% of the operating working distances are concentrated between 0.4m and 0.75m.

[0071] The four patient conditions and their corresponding movement patterns are as follows.

[0072] Firstly, in the reclining treatment state: when Ph is not lower than the preset headrest pressure threshold P_th, Pb is not lower than the preset back pressure threshold P_tb, Ps is not lower than the preset seat pressure threshold P_ts, F_face is effective, F_oral is stable, and d is within the effective working distance range [d_min, d_max], the aforementioned motion mode management module determines that the patient is in the reclining treatment state and allows the aforementioned control module to enter the oral cavity following illumination mode, that is, based on the deviation between the oral cavity target point Pm and the image center point P, the joint motors are driven to align with the oral cavity target area. The stable recognition criteria for F_face and F_oral require that the recognition validity condition be met in at least a preset number of stable frames N_stable. The value of N_stable ranges from 3 to 10 frames, and in this embodiment, it is set to 5 frames. The basis for this value is: based on the acquisition frequency of 10 frames / second for the camera 601, 5 frames correspond to 0.5 seconds. Actual measurements on images from the dental clinic show that the duration of noise in a single frame is less than 0.2 seconds. 5 frames can effectively filter out noise and misidentification, while not introducing a response delay of more than 0.5 seconds.

[0073] Secondly, in the resting state: when Ph is not lower than P_th, Pb is not lower than P_tb, and Ps is not lower than P_ts, but F_oral is unstable or F_face is invalid, or d exceeds the effective working distance range, the aforementioned motion mode management module determines that the patient is in the resting state, including situations such as the patient closing their mouth, waiting, and pausing operation. At this time, the aforementioned control module does not actively follow the target position of the oral cavity in the image, but maintains the current position of the lamp head 105 or moves to the preset standby position and remains stationary. It should be noted that in this state, the lamp arm stops following but does not perform a retraction action to avoid frequent reciprocating movements of the lamp arm during the patient's brief closure of the oral cavity. Its standby position stores the joint angle value of the last successful following, so that the following illumination can be quickly restored after the patient resumes opening their mouth.

[0074] Third, head off the headrest state: When Ph is lower than P_th but Ps is not lower than P_ts, the aforementioned motion mode management module determines that the patient's head has left the headrest but the body is still on the dental chair, corresponding to scenarios such as the patient getting up to rinse their mouth, adjusting their head posture, or cooperating with the doctor for photography. At this time, the aforementioned control module stops the oral cavity following lighting mode and controls the joint motors to drive the lamp arm to perform a retraction action, moving the lamp head 105 to the preset retraction position P_retreat, so that the lamp head 105 is away from the area where the patient's head may move; the aforementioned preset retraction position P_retreat corresponds to the posture where the lamp head 105 is retracted to the safe area above the rotating arm 102 and the lamp head optical axis is deviated from the patient's face. The specific joint angle values ​​are stored after being manually taught by the operator during system initialization.

[0075] Fourth, patient off-chair status: When Ph, Pb, and Ps are all below their respective pressure thresholds, the aforementioned motion mode management module determines that the patient has left the dental chair. At this time, the aforementioned control module controls the joint motors to drive the lamp arm back to the preset initial standby position and turns off the oral cavity following lighting mode; the aforementioned initial standby position is the standard storage posture preset at the factory, corresponding to the lamp head 105 being fully retracted and all joints being in the zero position.

[0076] For other sensor signal combinations besides the four types of state conditions mentioned above, such as when Pb is lower than the preset back pressure threshold P_tb but Ph is not lower than P_th and Ps is not lower than P_ts, the aforementioned motion mode management module defaults to classifying it into a resting state, stopping the oral cavity following illumination and maintaining the current position of the lamp head 105 until all the judgment conditions required for the patient's body position to return to the lying-back treatment state are met simultaneously.

[0077] During the operation of the aforementioned motion mode management module, a consistency verification of visual and pressure signals is also performed: the recognition result of F_face is cross-compared with the acquisition results of Ph and Pb. When F_face is valid but Ph is lower than P_th and Pb is lower than P_tb, the aforementioned motion mode management module prioritizes the pressure detection result to restrict the aforementioned control module from entering the oral cavity following illumination mode, and does not rely on the visual recognition result. It can be understood that the purpose of the above consistency verification logic is to handle scenarios where the patient's facial image remains in the field of view of the lamp head camera, but the patient has actually stood up or left the seat, to ensure that visual misrecognition will not cause the lamp arm to perform unexpected following movements when no one is being treated.

[0078] In addition, in the oral cavity following illumination mode, the mentioned motion mode management module also performs a brief occlusion handling logic: when the value of F_oral changes from stable to occluded, the mentioned motion mode management module records the current occlusion duration frame count value N_count; if N_count is lower than the preset continuous occlusion frame count threshold N_occlude, the mentioned control module maintains the lamp head pose when the oral cavity target recognition was successful in the previous frame and keeps it still; if N_count is not lower than N_occlude, the mentioned motion mode management module exits the oral cavity following illumination mode, determines the patient's state according to the current Ph, Pb and Ps values ​​and switches to the corresponding motion mode, preparing for the rest state or the head leaving the headrest state. The value of N_occlude ranges from 3 to 15 frames. In this embodiment, N_occlude is set to 8 frames. This value is based on video analysis of 10 typical dental procedures. The duration of brief occlusion caused by the doctor's hands and instruments is concentrated between 0.3 and 0.6 seconds. Calculated at an image acquisition frequency of 10 frames per second, 8 frames correspond to 0.8 seconds, which can cover more than 95% of brief occlusion scenarios, while not exceeding the duration of occlusion caused by changes in the patient's actual state, such as closing the mouth. It should be noted that the brief occlusion holding logic ensures that the lamp head does not need to leave the illumination position when the doctor's instruments briefly pass through the camera's field of view, thereby avoiding frequent positional jitter caused by occlusion and ensuring the continuous stability of the illumination in the surgical operation area.

[0079] The above-mentioned embodiments are merely preferred embodiments of the present invention and are not intended to limit the present invention; various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-joint active oral lamp, comprising: The column (101), the rotating arm (102), and the rotating arm module connected between the column (101) and the rotating arm (102) are used to drive the rotating arm (102) to rotate relative to the column (101) about a first vertical axis; The balance arm (103) and the balance arm module connected between the rotating arm (102) and the balance arm (103) are used to drive the balance arm (103) to rotate relative to the rotating arm (102) about a second vertical axis and to drive the balance arm (103) to perform pitch motion. Lamp head bracket (104), and lamp head bracket module connected between the balance arm (103) and the lamp head bracket (104), for driving the lamp head bracket (104) to rotate relative to the balance arm (103) about a third vertical axis; The lamp head (105) and the lamp head module connected between the lamp head bracket (104) and the lamp head (105) are used to drive the lamp head (105) to rotate about a horizontal axis relative to the lamp head bracket (104).

2. The multi-joint active oral lamp according to claim 1, wherein, The rotating arm module, the balance arm module, and the lamp head bracket module all include a drive motor integrated in the corresponding module housing. The rotational motion of the drive motor is transmitted to the corresponding rotating arm (102), balance arm (103), or lamp head bracket (104) via the module housing.

3. The multi-joint active oral lamp according to claim 2, wherein, The rotating arm module includes a lower outer shell (201) connected to the column (101), an upper outer shell (205) connected to the rotating arm (102), and a rotating arm module bushing (202) disposed between the lower outer shell (201) and the upper outer shell (205). The rotating arm module bushing (202) and the upper outer shell (205) form a clearance fit to generate an oil film during operation.

4. The multi-joint active oral lamp according to claim 2, wherein, The rotating arm module also includes a rotating arm module rotating shaft (207), the axis of which is perpendicular to the axis of the flange shaft that transmits the torque of the drive motor in the rotating arm module, so as to provide radial support when the upper housing (205) of the rotating arm module rotates.

5. The multi-joint active oral lamp according to claim 2, wherein, The balance arm module includes a four-bar linkage, which is driven by the balance module lifting motor (309) to enable the balance arm (103) to perform pitch motion.

6. A method for controlling a multi-joint active oral lamp, used to control the multi-joint active oral lamp according to any one of claims 1 to 5, comprising: Acquire patient-related signals collected by the acquisition module; Based on the comparison results between the patient-related signals and preset conditions, the current working mode of the multi-joint active oral lamp is determined. In the working mode that allows following illumination, at least some of the modules of the rotating arm module, the balance arm module, the lamp head bracket module and the lamp head module are driven to move based on the position information of the target area of ​​the oral cavity, so that the illumination optical axis of the lamp head (105) is aligned with the target area of ​​the oral cavity.

7. The control method according to claim 6, wherein, The acquisition module includes a camera (601) mounted on the lamp head (105), and the patient-related signals include oral cavity area images acquired by the camera (601); The method of driving the movement of each module based on the position information of the oral cavity target area includes: extracting the spatial angle deviation of the target illumination area from the oral cavity area image; calculating the driving increment of each module through inverse kinematics based on the spatial angle deviation and the current joint angle value fed back by the encoder of each joint module; and driving the movement of the corresponding module based on the driving increment.

8. The control method according to claim 7, wherein, The acquisition module also includes a pressure detection unit and a distance detection unit. The pressure detection unit is configured to acquire the patient's positional pressure signal on the dental chair, and the distance detection unit is configured to acquire the distance information from the lamp head (105) to the patient's face. The determination of the current working mode based on the comparison result of the patient-related signals and preset conditions includes: determining the current working mode based on at least two of the postural pressure signal, the distance information and the face recognition result of the camera (601); The operating modes include at least two of the following: oral cavity following illumination mode, ready state mode, yielding mode, and standby mode.

9. The control method according to claim 8, wherein, During the operation of the oral cavity following illumination mode, when the target area of ​​the oral cavity cannot be identified due to occlusion of the image captured by the camera (601), if the number of consecutive occlusion frames does not exceed the preset occlusion frame threshold, the current illumination position of the lamp head (105) is maintained. If the number of consecutive occlusion frames exceeds the preset occlusion frame threshold, the oral cavity following illumination mode is exited.

10. The control method according to claim 7, wherein, After completing the movement of each module, the process further includes: acquiring the illuminance value of the target area collected by the illuminance sensor installed around the lamp head (105); based on the comparison result of the illuminance value and the preset minimum illuminance threshold, if the illuminance value is lower than the minimum illuminance threshold, triggering compensation movement; and adjusting the preset minimum illuminance threshold based on the statistics of the number of illuminance compensation triggers within the preset evaluation window.

Images