Master-slave ophthalmic surgical robot and instrument axis mapping control method therefor

Abstract

An instrument axis mapping control method for a master-slave ophthalmic surgical robot, comprising: setting an instrument end trajectory division rule, and taking each divided trajectory segment as a separate control unit; at a trajectory starting point of each control unit, creating a virtual axis parallel to an instrument axis in space and fixing the virtual axis to a master manipulator end, obtaining a yaw angle and a pitch angle of the instrument at the trajectory starting point, and at each subsequent node after the trajectory starting point, acquiring a yaw angle and a pitch angle of the virtual axis at the node; and scaling a yaw angle change amount and a pitch angle change amount on the basis of a set scaling coefficient. After the trajectory starts, the instrument is controlled to execute a corresponding yaw angle and pitch angle at the trajectory starting point of each control unit, and at each subsequent node after the trajectory starting point, corresponding scaled yaw angle and pitch angle change amounts are executed. Also disclosed is a master-slave ophthalmic surgical robot. The method solves the problem in the prior art of poor adjustment accuracy caused by no scaling function when the orientation of the instrument is controlled.

Description

Master-slave ophthalmic surgery robot and instrument axis mapping control method thereof TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a master-slave ophthalmic surgery robot and an instrument axis mapping control method thereof. BACKGROUND

[0002] In the process of performing fundus surgery, the surgical instrument needs to be inserted into the eye from the scleral sleeve. This mode of operation requires the ophthalmic surgery robot to perform RCM motion (RCM is the abbreviation of Remote motion center, i.e. remote motion center). RCM motion has 4 degrees of freedom, namely yaw, pitch, roll and feed, as shown in FIG. 1. Most existing master-slave ophthalmic surgery robots use passive RCM mechanisms, that is, each RCM motor controls one RCM degree of freedom.

[0003] The existing master-slave ophthalmic surgery robot usually adopts absolute mapping when mapping the posture. This mapping method decomposes the rotation matrix of the master hand into three rotation angles R x 、R y 、R z representing the rotation of the x, y, z axes, and then sets the end of the slave hand to follow this position. In this way, the three angle rotations R x 、R y 、R z have a very complex correspondence with the three rotations of the RCM motion, so the corresponding RCM motor rotation change cannot be directly solved, and the proportional scaling adjustment cannot be realized.

[0004] In the process of using the master-slave ophthalmic surgery robot to perform surgery, after aligning the RCM point with the scleral sleeve, the instrument axis needs to be aligned with the sleeve axis as much as possible to facilitate needle insertion. The existing master-slave posture mapping method usually adopts 1:1 proportional mapping when controlling the posture, which loses the scaling function and results in poor adjustment accuracy. SUMMARY

[0005] In view of the above analysis, the embodiments of the present application aim to provide a master-slave ophthalmic surgery robot and an instrument axis mapping control method thereof, to solve the problem of poor adjustment accuracy caused by the lack of scaling function when controlling the instrument posture in the prior art.

[0006] In one aspect, the embodiments of the present application provide an instrument axis mapping control method of a master-slave ophthalmic surgery robot, comprising the following steps:

[0007] Setting the instrument end trajectory division rule of the RCM mechanism, and taking each trajectory segment after division as a separate control unit;

[0008] At the trajectory starting point of each control unit, a virtual axis parallel to the instrument axis in space is virtually fixed at the end of the master hand, and a rotation matrix of the coordinate system of the end of the master hand to the virtual axis is obtained and the instrument deflection angle at the trajectory starting point is recorded pitch angle θ s ;

[0009] At each node after the trajectory starting point of the control unit, the posture of the end of the master hand is obtained, and based on the above-mentioned rotation matrix the posture of the virtual axis simulating the posture of the end of the master hand in the coordinate system of the RCM point is obtained, and then the deflection angle of the virtual axis at the node is obtained pitch angle θ

[0010] According to the above-mentioned deflection angle and pitch angle θ and θ s , the deflection angle change amount and the pitch angle change amount of the virtual axis at each node after the trajectory starting point in the control unit are obtained, and then the deflection angle change amount and the pitch angle change amount are scaled according to the set scaling factor;

[0011] After the trajectory starts, the RCM motor is controlled to drive the instrument to execute the above-mentioned deflection angle pitch angle θ s at the trajectory starting point of each control unit, and to execute the scaled deflection angle change amount pitch angle change amount Δθ at each node after the trajectory starting point.

[0012] The beneficial effects of the above technical solution are as follows: a method for calculating and planning the instrument axis posture under the condition of the end posture of the master hand is designed, the master hand posture information is decomposed into two posture angles corresponding to the RCM mechanism, the two RCM rotation parameter change amounts (deflection angle change amount and pitch angle change amount) corresponding to the change of the master hand posture are calculated, and then a mapping ratio (set scaling factor) is multiplied to control the corresponding RCM motor, so as to realize the incremental axis mapping control, and high-precision posture adjustment can be realized by adjusting the scaling ratio.

[0013] Based on the above method, after the step of recording the deflection angle pitch angle θ s of the instrument at the trajectory starting point, the step of controlling the RCM motor to drive the instrument to execute the above-mentioned deflection angle pitch angle θ s at the trajectory starting point of each control unit is directly executed; and after the step of further scaling the deflection angle change amount and the pitch angle change amount according to the set scaling factor, the step of executing the scaled deflection angle change amount the step of obtaining the yaw angle variation Δφ, the step of obtaining the pitch angle variation Δθ, and the step of obtaining the roll angle variation Δψ, are performed before the start of the trajectory, to realize the asynchronous alignment function of the instrument axis and the master hand end position.

[0014] Further, the step of further scaling the yaw angle variation Δφ, the pitch angle variation Δθ, and the roll angle variation Δψ according to the set scaling factor, is performed before the start of the trajectory, to realize the asynchronous alignment function of the instrument axis and the master hand end position.

[0015] Further, the step of obtaining the rotation matrix R from the master hand end coordinate system to the virtual axis Further comprises the following sub-steps:

[0016] Obtaining the instrument end pose at the trajectory starting point in the RCM point coordinate system

[0017] According to the virtual axis pose The rotation matrix R from the master hand end coordinate system to the virtual axis is obtained by the following formula:

[0018]

[0019] In the formula, R is the rotation matrix from the master base coordinate system to the RCM point coordinate system, R is the rotation matrix from the master hand end coordinate system to the master base coordinate system at the trajectory starting point.

[0020] Further, the instrument end pose Is expressed by the following formula:

[0021]

[0022] In the formula, φ is the roll angle of the instrument at the trajectory starting point, θ s ω is the pitch angle of the instrument at the trajectory starting point s ψ is the rotation angle of the instrument at the trajectory starting point.

[0023] Further, the virtual axis pose in the RCM point coordinate system is obtained based on the rotation matrix Further, the yaw angle φ, the pitch angle θ, and the roll angle ψ of the node are obtained. The step of obtaining the yaw angle φ, the pitch angle θ, and the roll angle ψ of the node further comprises the following sub-steps:

[0024] Obtaining the master hand end pose in the master hand coordinate system

[0025] According to the master hand end pose Combined with the rotation matrix The pose of the virtual axis relative to the master hand coordinate system is obtained by the following formula

[0026]

[0027] According to the pose of the virtual axis relative to the master hand coordinate system The pose of the virtual axis simulating the pose of the master hand end in the RCM point coordinate system is obtained by the following formula

[0028]

[0029] In the formula, is the rotation matrix of the RCM point coordinate system transformation to the master base coordinate system;

[0030] The yaw angle of the virtual axis at the node is obtained by the following formula The pitch angle θ,

[0031]

[0032] Further, the change amount of the yaw angle after scaling is obtained by the following formula The pitch angle change amount Δθ:

[0033]

[0034] Δθ=k(θ-θ s )

[0035] In the formula, k is a scaling factor.

[0036] Further, the scaling factor k is not equal to 1; or,

[0037] The scaling factors corresponding to different trajectory segments are different.

[0038] Further, the instrument end trajectory division rule includes at least one of the equal time division rule, the equal distance division rule, and the equal amplitude division rule.

[0039] On the other hand, the embodiment of the present application provides a master-slave ophthalmic surgery robot, which comprises a 6-axis mechanical arm and a passive RCM mechanism attached to the end of the 6-axis mechanical arm; and,

[0040] The end of the RCM mechanism is provided with an instrument controlled by an RCM motor; the instrument includes a surgical instrument and a non-surgical instrument;

[0041] The master-slave ophthalmic surgery robot executes the instrument axis mapping control method described above.

[0042] The following presents a summary of the application in order to provide a basic understanding of some aspects of the application. This summary is not an extensive overview of the application. It is not intended to identify key / critical elements of the application or to delineate the scope of the application. Its sole purpose is to present some concepts of the application in a simplified form as a prelude to the more detailed description that is presented later. BRIEF DESCRIPTION OF DRAWINGS

[0043] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which like reference characters refer to like elements throughout the figures, and in which:

[0044] FIG. 1 shows a schematic diagram of RCM motion in the background art;

[0045] FIG. 2 shows a schematic diagram of steps of a device axis mapping control method of embodiment 1;

[0046] FIG. 3 shows a schematic diagram of steps of a device axis mapping control method of embodiment 2;

[0047] FIG. 4 shows a schematic diagram of a master-slave ophthalmic surgery robot of embodiment 3;

[0048] FIG. 5 shows a schematic diagram of a device tip pose of embodiment 3 (correspondence between RCM parameters and Cartesian coordinate system position);

[0049] FIG. 6 shows a schematic diagram of coordinate systems of a master-slave ophthalmic surgery robot system of embodiment 3;

[0050] FIG. 7 shows a schematic diagram of an axis following algorithm of embodiment 3;

[0051] FIG. 8 shows a structural block diagram of a nonlinear programming algorithm of embodiment 3. DETAILED DESCRIPTION

[0052] Embodiments of the present application will be described herein below with reference to the drawings. While embodiments of the present application are shown in the drawings, it is understood that the present application can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0053] The term "comprising" and variations thereof as used herein are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. The term "or" as used herein is intended to mean an inclusive "or" unless otherwise indicated. The term "based on" means "based, at least in part, on." The terms "one example embodiment" and "an example embodiment" as used herein refer to at least one example embodiment. The term "another embodiment" as used herein refers to at least one additional embodiment. The terms "first," "second," and the like as used herein do not necessarily denote any order, quantity, or importance, but are used to denote different or additional elements. Other definitions can be found in the detailed description.

[0054] Firstly, the key terms related to the present application and their physical definitions are introduced as follows.

[0055] RCM point coordinate system, as shown in FIG. 1, is a coordinate system with the remote center of motion fixed point (RCM point) as the origin. The x-axis (X-axis) of the RCM point coordinate system is opposite to the z-axis (Z-axis) of the RCM mechanism base coordinate system, and the z-axis (or Z-axis) is opposite to the x-axis (X-axis) of the RCM mechanism base coordinate system. After the two axes are determined, the y-axis (Y-axis) is determined by the right-hand rule.

[0056] RCM mechanism base coordinate system, as shown in FIG. 1, is a coordinate system with the RCM mechanism installation position as the origin. The z-axis (Z-axis) points to the RCM point, and the x-axis (X-axis) points to the position when the yaw angle φ is 0. After the two axes are determined, the y-axis (Y-axis) is determined by the right-hand rule.

[0057] Mechanical arm base coordinate system, as shown in FIG. 1, is a coordinate system representing the position of the mechanical arm base. The origin, x-axis (X-axis), y-axis (Y-axis), and z-axis (or Z-axis) have default specifications of commercial products.

[0058] Master hand base coordinate system, as shown in FIG. 1, is a coordinate system representing the position of the master hand base. The origin, x-axis (X-axis), y-axis (Y-axis), and z-axis (or Z-axis) have default specifications of commercial products.

[0059] Master hand end coordinate system (also referred to as master hand coordinate system), as shown in FIG. 1, is a coordinate system representing the position of the master hand end. The origin, x-axis (X-axis), y-axis (Y-axis), and z-axis (or Z-axis) have default specifications of commercial products.

[0060] Instrument end coordinate system (also referred to as surgical instrument coordinate system), as shown in FIG. 1, is a coordinate system representing the pose of the instrument end. The origin, x-axis (X-axis), y-axis (Y-axis), and z-axis (or Z-axis) have default specifications of commercial products.

[0061] The orientations of the axes of the above-mentioned coordinate systems are not absolutely specified. The mechanical arm and the master hand are both off-the-shelf commercial products with their default specifications. Therefore, the default coordinate systems can be used between the mechanical arm base coordinate system, the master hand base coordinate system, and the master hand coordinate system.

[0062] A set of instrument axis mapping control method is designed for a slave hand with a passive RCM structure. After calculating the change amount of the two RCM rotation angle parameters corresponding to the change of the master hand pose, a mapping scale (a set scaling factor) is multiplied to control the corresponding RCM motor. The slave hand is composed of a mechanical arm and a passive RCM mechanism attached to the end.

[0063] Embodiment 1

[0064] One embodiment of the present application discloses a master-slave ophthalmic surgery robot instrument axis mapping control method, which has the function of realizing the synchronous alignment of the instrument axis and the master hand end position, as shown in FIG. 2, and comprises the following steps:

[0065] S1. Setting the instrument end trajectory division rule of the RCM mechanism, and taking each trajectory segment after division as a separate control unit;

[0066] S2. After the start of the trajectory, virtually fixing a virtual axis parallel to the instrument axis in space at the trajectory starting point of each control unit at the master hand end to obtain the rotation matrix of the master hand end coordinate system to the virtual axis and record the instrument deflection angle at the trajectory starting point pitch angle θ s ; controlling the RCM motor to drive the instrument to execute the above-mentioned deflection angle pitch angle θ s at the trajectory starting point of each control unit;

[0067] S3. Obtaining the master hand end posture at each node after the trajectory starting point of the control unit, and obtaining the posture of the virtual axis simulating the master hand end posture in the RCM point coordinate system based on the above-mentioned rotation matrix to obtain the deflection angle pitch angle θ of the virtual axis at the node;

[0068] S4. According to the above-mentioned deflection angle and pitch angle θ and θ s , obtaining the deflection angle change and pitch angle change of the virtual axis at each node after the trajectory starting point in the control unit, and then scaling the deflection angle change and pitch angle change according to the set scaling coefficient;

[0069] S5. Executing the scaled deflection angle change pitch angle change Δθ at each node after the trajectory starting point.

[0070] It should be noted that according to the different structures of the RCM mechanism, the representation of the RCM point coordinate system is not only the x-y-z Euler angle representation, but also y-x-z, etc. When different Euler angle representation methods are adopted, the expressions of the initial posture and the target posture are different. According to the different establishment methods of the coordinate system, the expression of the instrument end posture (the posture of the virtual axis) in the RCM point coordinate system is different.

[0071] In implementation, the structure of the master-slave ophthalmic surgery robot is shown in FIG. 4-7, and the above control method takes trajectory segment as the control unit. The above method relates to a control method for a passive RCM structure slave hand. The method can be applied to any existing passive RCM mechanism slave hand. The key technical points involved include: deriving the virtual axis and the relative pose of the master hand end according to the instrument axis position of the slave hand at the trajectory starting point (step S2); calculating the pose of the virtual axis represented in the RCM coordinate system (step S3); and the method of decomposing the pose of the virtual axis in the RCM coordinate system into corresponding RCM attitude angle parameters (step S4, step S5).

[0072] Compared with the prior art, the embodiment discloses a method for calculating the instrument axis pose under the planning condition according to the master hand end pose, decomposes the master hand pose information into two attitude angles corresponding to the RCM mechanism, calculates the change amount of the two RCM rotation angle parameters (roll angle change amount, pitch angle change amount) corresponding to the change of the master hand pose, and then multiplies a mapping scale (a set scaling factor) to control the corresponding RCM motor, so that the incremental axis mapping control is realized, the high-precision pose adjustment can be realized by adjusting the scaling scale, and the synchronous alignment function of the instrument axis and the master hand end pose is realized.

[0073] Embodiment 2

[0074] Another embodiment of the application discloses an instrument axis mapping control method of a master-slave ophthalmic surgery robot, which has an asynchronous alignment function of the instrument axis and the master hand end pose, as shown in FIG. 3, and the method comprises the following steps:

[0075] S1'. Setting the instrument end trajectory division rule of the RCM mechanism, and taking each trajectory segment after division as a separate control unit;

[0076] S2'. At the trajectory starting point of each control unit, a virtual axis parallel to the instrument axis in space is virtually fixed at the master hand end, a rotation matrix of the master hand end coordinate system transformation to the virtual axis is obtained and the roll angle of the instrument at the trajectory starting point is recorded the pitch angle θs ；

[0077] S3'. At each node after the trajectory starting point of the control unit, the master hand end pose is obtained, and based on the above rotation matrix the pose of the virtual axis simulating the master hand end pose in the RCM point coordinate system is obtained, and then the roll angle of the virtual axis at the node is obtained the pitch angle θ;

[0078] S4'. According to the above roll angle and pitch angle θ and θ s obtain the yaw angle variation and the pitch angle variation of the virtual axis at each node after the starting point of the trajectory in the control unit, and then scale the yaw angle variation and the pitch angle variation according to the set scaling factor;

[0079] S5’. After the start of the trajectory, the RCM motor is controlled to drive the instrument to perform the yaw angle pitch angle θ s and the scaled yaw angle variation at each node after the starting point of the trajectory pitch angle variation Δθ.

[0080] In implementation, the structure of the master-slave ophthalmic surgical robot is shown in FIGS. 4-7, and the above control method takes a trajectory segment as a control unit. The above method relates to a control method for a slave hand of a passive RCM structure. The method can be applied to any existing slave hand of a passive RCM mechanism. Key technical points involved include: deriving the virtual axis and the relative pose of the master hand end from the instrument axis position at the starting point of the trajectory (step S2); calculating the pose of the virtual axis represented in the RCM coordinate system (step S3); and the method of decomposing the pose of the virtual axis in the RCM coordinate system into corresponding RCM attitude angle parameters (step S4, step S5).

[0081] Compared with the prior art, the embodiment discloses a method of calculating the instrument axis pose under planning conditions according to the master hand end pose, decomposing the master hand pose information to two attitude angles corresponding to the RCM mechanism, calculating the variation of the two RCM rotation angle parameters (yaw angle variation and pitch angle variation) corresponding to the variation of the master hand pose, and multiplying the variation by a mapping ratio (a set scaling factor) to control the corresponding RCM motor, thereby realizing incremental axis mapping control, and achieving high-precision pose adjustment by adjusting the scaling ratio. The asynchronous alignment function of the instrument axis and the master hand end pose is realized (operation is designed in advance).

[0082] Embodiment 3

[0083] On the basis of Embodiment 1 or Embodiment 2, the master-slave ophthalmic surgical robot is composed of a 6-axis mechanical arm and an RCM mechanism attached to the end.

[0084] The control method takes a trajectory segment as a control unit, the instrument end trajectory of the RCM mechanism is the master hand trajectory, and a trajectory segment is defined as a series of master hand positions and attitude points during the time when the master hand button is pressed. The first point is the starting point of the trajectory. A virtual axis parallel to the instrument axis is fixed at the master hand end at the starting point of the trajectory, and the yaw angle and the pitch angle of the virtual axis in the RCM point coordinate system are calculated in the subsequent points of the trajectory (FIG. 7).

[0085] The control method needs to solve two attitude angles (yaw angle pitch angle θ) of the following target in the RCM point coordinate system.

[0086] Preferably, the step of obtaining the rotation matrix of the master hand end coordinate system to the virtual axis in step S2 or step S2' further comprises the following sub-steps:

[0087] S21. Obtain the instrument end attitude at the trajectory starting point in the RCM point coordinate system

[0088] S22. Obtain the virtual axis attitude at the trajectory starting point according to the instrument end attitude The rotation matrix of the master hand end coordinate system to the virtual axis is obtained by the following formula:

[0089]

[0090] In the formula, is the rotation matrix of the master hand base coordinate system to the RCM point coordinate system, is the rotation matrix of the master hand end coordinate system to the master hand base coordinate system at the trajectory starting point.

[0091] Preferably, the instrument end attitude is expressed by the following formula:

[0092]

[0093] In the formula, is the yaw angle of the instrument at the trajectory starting point, θ s is the pitch angle ω of the instrument at the trajectory starting point s is the roll angle of the instrument at the trajectory starting point.

[0094] Preferably, the step of obtaining the virtual axis attitude in the RCM point coordinate system based on the rotation matrix and further obtaining the yaw angle pitch angle θ of the node in step S3 or step S3' further comprises the following sub-steps:

[0095] S31. Obtain the master hand end attitude in the master hand coordinate system

[0096] S32. Obtain the virtual axis attitude relative to the master hand coordinate system according to the master hand end attitude combined with the rotation matrix The virtual axis attitude relative to the master hand coordinate system is obtained by the following formula: ​

[0097]

[0098] S33. The pose of the virtual axis relative to the master coordinate system is determined according to the pose of the virtual axis The pose of the virtual axis in the RCM point coordinate system is obtained by the following formula

[0099]

[0100] wherein, is the rotation matrix of the RCM point coordinate system transformed to the master base coordinate system;

[0101] S34. The yaw angle of the virtual axis at the node is obtained by the following formula the pitch angle θ,

[0102]

[0103] Preferably, step 4 obtains the scaled yaw angle change amount by the following formula the pitch angle change amount Δθ:

[0104]

[0105] Δθ = k(θ - θ s ) (6)

[0106] wherein k is a scaling factor. Optionally, the scaling factor k is set to be not equal to 1.

[0107] Preferably, the scaling factors corresponding to different trajectory segments are different.

[0108] Preferably, the instrument end trajectory division rule includes at least one of an equal time division rule, an equal distance division rule, and an equal amplitude division rule.

[0109] Derivation process: according to the mechanism of the RCM mechanism, the instrument end pose of all nodes in each trajectory segment in the RCM point coordinate system can be expressed by x-y-z Euler angles:

[0110]

[0111] It is obtained that:

[0112]

[0113] wherein, is the rotation matrix of the RCM point coordinate system rotated around its x axis by is the rotation matrix of the RCM point coordinate system rotated around its y axis byy (θ) is the rotation matrix of the RCM point coordinate system rotating around its x axis by θ, F(θ) is the rotation matrix of the resulting coordinate system rotating around its y axis by θ, F(ω) is the rotation matrix of the resulting coordinate system rotating around its z axis by ω. z (ω) is the rotation matrix of the RCM point coordinate system rotating around its x axis by ω, F(θ, ω) is the rotation matrix of the resulting coordinate system rotating around its y axis by θ and finally rotating around its z axis by ω. is the yaw angle of the instrument, θ is the pitch angle of the instrument, and ω is the roll angle of the instrument.

[0114] where the roll angle ω does not affect the needle insertion during the axis adjustment, so only the yaw angle and the pitch angle θ need to be calculated. To perform the subsequent calculations, a coordinate system is established for the master-slave ophthalmic surgical robot system (Fig. 6).

[0115] The pose of the virtual axis with respect to the master coordinate system may be represented as:

[0116]

[0117] where, is the pose of the master end-effector in the master coordinate system, is the rotation matrix from the master end-effector to the virtual instrument axis.

[0118] is represented in the RCM point coordinate system, i.e., solving for

[0119]

[0120] where, is the rotation matrix of the RCM point coordinate system transforming to the master base coordinate system.

[0121] In the same end-trajectory is a constant value determined by the surgical instrument pose and the master end-effector pose at the start point of the trajectory. is calculated as follows:

[0122]

[0123] where, is the rotation matrix of the master end-effector coordinate system at the start point of the trajectory transforming to the master base coordinate system, is the rotation matrix of the master base coordinate system transforming to the RCM point coordinate system, is the virtual axis pose at the start point of the trajectory in the RCM point coordinate system.

[0124] Therefore, the virtual axis pose in the RCM point coordinate system is as follows:

[0125]

[0126] The corresponding two attitude angles can be solved:

[0127]

[0128] After solving, the corresponding change amount is calculated, and then multiplied by the scaling factor to obtain the change amount corresponding to the hand, so as to control the corresponding RCM motor to proportionally control the instrument attitude (Fig. 8).

[0129] Compared with the embodiment 1 or the embodiment 2, the instrument axis mapping control method of the master-slave ophthalmic surgery robot provided by the embodiment has the following beneficial effects:

[0130] 1. After the trajectory starts, the instrument (instrument axis) and the following target (master hand) are automatically aligned or asynchronously aligned in space, which has the advantages of intuitiveness and high efficiency.

[0131] 2. The relative scaling control of the attitude mapping is realized, and better control accuracy is achieved.

[0132] 3. The scaling ratio of each trajectory segment is independent and adjustable, and the control feeling is adjustable.

[0133] Embodiment 4

[0134] The embodiment of the application provides a master-slave ophthalmic surgery robot, which comprises a 6-axis mechanical arm and a passive RCM mechanism attached to the end of the 6-axis mechanical arm.

[0135] The end of the RCM mechanism is provided with an instrument controlled by an RCM motor. The instrument comprises surgical instruments (including knives) and non-surgical instruments (including disinfection instruments, anesthesia instruments).

[0136] The master-slave ophthalmic surgery robot executes the instrument axis mapping control method described in the above-mentioned embodiment 1, embodiment 2 or embodiment 3.

[0137] The above has described the embodiments of the application, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles, practical application or improvement of the prior art of the embodiments, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. An instrument axis mapping control method for a master-slave ophthalmic surgical robot, characterized in that, The method comprises the following steps: Setting a trajectory division rule of the instrument end of the RCM mechanism, and taking each trajectory segment after division as a separate control unit; At the trajectory starting point of each control unit, a virtual axis parallel to the instrument axis in space is virtually fixed at the master hand end, and a rotation matrix of the master hand end coordinate system to the virtual axis is obtained and record the instrument's yaw angle at the start of the trajectory pitch angle θ s ; At each node after the starting point of the trajectory of the control unit, the pose of the master hand end is acquired, and the rotation matrix is calculated based on the above-mentioned rotation matrix The pose of the virtual axis simulating the pose of the master hand end in the RCM point coordinate system is obtained, and then the yaw angle of the virtual axis at the node is obtained a pitch angle θ; According to the yaw angle and , the pitch angle θ and θ s , obtain the yaw angle variation and the pitch angle variation of the virtual axis at each node after the starting point of the track in the control unit, and then scale the yaw angle variation and the pitch angle variation according to the set scaling coefficient; After the trajectory starts, control the RCM motor to drive the instrument to perform the above-described deflection angle at the trajectory starting point of each control unit θ s and the change in the yaw angle after scaling at each node after the start of the trajectory a pitch angle change amount Δθ.

2. The master-slave ophthalmic surgical robotic instrument axis mapping control method of claim 1, wherein, The yaw angle of the instrument at the starting point of the recorded trajectory. Pitch angle θ s Following the steps, the control RCM motor drive device is directly executed to perform the aforementioned yaw angle at the trajectory starting point of each control unit. Pitch angle θ s The steps are as follows: and, after the step of scaling the yaw angle change and pitch angle change according to the set scaling factor, the scaling of the yaw angle change is directly performed at each node after the trajectory start point. The steps of adjusting the pitch angle Δθ are used to achieve synchronous alignment between the instrument axis and the end effector position.

3. The master-slave ophthalmic surgical robotic instrument axis mapping control method of claim 1, wherein, The step of further scaling the yaw angle change amount and the pitch angle change amount according to the set scaling coefficient is performed before the start of the trajectory, so as to realize the asynchronous alignment function of the instrument axis and the master hand end pose.

4. The master-slave ophthalmic surgical robotic instrument axis mapping control method of claim 2 or 3, wherein, the step of obtaining a rotation matrix of the master hand end-effector coordinate system transformation to the virtual axis further comprises the sub-step of: obtaining an instrument end pose at a trajectory start point in the rcm point coordinate system According to the virtual axis pose , the rotation matrix from master hand end-effector coordinate system to virtual axis is obtained by the following equation In the formulae, a rotation matrix for transforming the master hand base coordinate system to the RCM point coordinate system, A rotation matrix for coordinate system transformation of the master hand end at the trajectory starting point to the master hand base.

5. The master-slave ophthalmic surgical robotic instrument axis mapping control method of claim 4, wherein, The instrument tip pose is expressed by the following equation: In the formulae, θ is the yaw angle of the instrument at the start of the trajectory s ω is the pitch angle of the instrument at the start of the trajectory s is the roll angle of the instrument at the start of the trajectory.

6. The master-slave ophthalmic surgical robotic instrument axis mapping control method of claim 5, wherein, said rotation matrix The pose of the virtual axis in the RCM coordinate system is obtained, and then the yaw angle of the node is obtained The step of obtaining the pitch angle θ further comprises the following sub-steps: acquiring the pose of the master hand end in the master hand coordinate system According to the master hand end posture , in conjunction with a rotation matrix The pose of the virtual axis with respect to the master hand coordinate system is obtained by the following equation According to the pose of the virtual axis relative to the master hand coordinate system The pose of the virtual axis simulating the pose of the end of the master hand in the RCM coordinate system is obtained by the following formula In the formulae, A rotation matrix for coordinate system transformation of the RCM point to the master hand base. The yaw angle of the virtual axis at the node is obtained by the following equation , pitch angle θ, 7. The master-slave ophthalmic surgical robotic instrument axis mapping control method of claim 6, wherein, The scaled yaw angle change amount is obtained by the following equation , the pitch angle change amount Δθ: In the formula, k is the scaling coefficient.

8. The master-slave ophthalmic surgical robotic instrument axis mapping control method of claim 7, wherein, The scaling coefficient k is not equal to 1; or, The scaling coefficients corresponding to different trajectory segments are different.

9. The master-slave ophthalmic surgical robotic instrument axis mapping control method of any of claims 5-8, wherein, The instrument end trajectory division rule comprises at least one of an equal time division rule, an equal distance division rule, and an equal amplitude division rule.

10. A master-slave ophthalmic surgical robot, characterized by, The master-slave ophthalmic surgical robot comprises a 6-axis mechanical arm and a passive RCM mechanism attached to the end of the 6-axis mechanical arm; and An instrument controlled by an RCM motor is arranged at the end of the RCM mechanism; the instrument comprises a surgical instrument and a non-surgical instrument; The master-slave ophthalmic surgical robot executes the instrument axis mapping control method according to any one of claims 1-9.

Images