Gripping force determination method for a gripping instrument and surgical robot system

Abstract

This disclosure provides a method for detecting the clamping force of a clamping device, comprising: determining a current for a drive motor for driving the clamping device, the drive motor being used to drive the clamping device to open and close; comparing the current of the drive motor with an initial current; and determining the clamping force of the clamping device based on the comparison.

Description

Technical Field

[0001] This disclosure relates to the fields of machinery and robotics, and in particular to a method for determining the clamping force of clamping instruments and a surgical robot system. Background Technology

[0002] Minimally invasive surgery has become a widely used surgical procedure in recent years, characterized by less surgical trauma and shorter patient recovery time. The advent of surgical robots has further enhanced the precision and stability of minimally invasive surgery.

[0003] During robotic surgery, surgical instruments are remotely controlled to operate on the surgical site. During this process, the instruments come into direct contact with the tissue. For example, clamping instruments may grip the tissue. The operator (e.g., the surgeon) may need to be aware of the clamping forces exerted on the tissue by these instruments during the procedure.

[0004] Typically, clamping force can be detected by adding sensors, such as pressure sensors. This increases the structural complexity of the surgical instruments, their size and weight, as well as the difficulty of controlling them and the likelihood of malfunction. Summary of the Invention

[0005] Some embodiments of this disclosure provide a method for determining the clamping force of a clamping device, comprising: determining a current for a drive motor for driving the clamping device, the drive motor being used to drive the clamping device to open and close; comparing the current of the drive motor with an initial current; and determining the clamping force of the clamping device based on the comparison.

[0006] Some embodiments of this disclosure provide a computer-readable medium having instructions stored thereon that, when executed by a processor, cause a computer to perform a method according to some embodiments of this disclosure.

[0007] Some embodiments of this disclosure provide a surgical robot system, including: at least one carriage; at least one positioning arm connected to the at least one carriage; at least one surgical instrument detachably connected to the distal end of the at least one positioning arm, the at least one surgical instrument including a clamping device, the clamping device including a clamp and a drive wire for driving the clamp to open and close; and a processor for performing a method according to some embodiments of this disclosure. Attached Figure Description

[0008] Figure 1 A schematic diagram of a clamping device according to some embodiments of the present disclosure is shown.

[0009] Figure 2 A cross-sectional schematic diagram of a clamping device according to some embodiments of the present disclosure is shown.

[0010] Figures 3(a) and 3(b) show flowcharts of methods for determining the clamping force of a clamping device according to some embodiments of the present disclosure.

[0011] Figure 4 The diagram shows time-current graphs of a drive motor for a drive clamping device according to some embodiments of the present disclosure.

[0012] Figure 5 A perspective view of a clamp according to some embodiments of the present disclosure is shown.

[0013] Figure 6 A cross-sectional schematic diagram of the pliers head according to some embodiments of the present disclosure is shown.

[0014] Figure 7 A partial cross-sectional view of a clamp according to some embodiments of the present disclosure is shown.

[0015] Figure 8 A schematic diagram of a surgical robot system according to some embodiments of the present disclosure is shown. Detailed Implementation

[0016] The embodiments of this disclosure will be described in detail below with reference to the accompanying drawings to provide a clearer understanding of the purpose, features, and advantages of this disclosure. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of this disclosure, but are merely illustrative of the essential spirit of the technical solutions disclosed.

[0017] In the description of this disclosure, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this disclosure and for simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installed," "connected," "coupled," and "coupled" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.

[0018] In this disclosure, the end closer to the operator (e.g., a doctor) is defined as the proximal end, proximal or posterior end, or posterior part, and the end closer to the surgical patient is defined as the distal end, distal or anterior end, or anterior part. Those skilled in the art will understand that the growable device according to embodiments of this disclosure can be used in the medical field as well as in other non-medical fields.

[0019] Figure 1 A schematic diagram of a clamping device 100 according to some embodiments of the present disclosure is shown. For example... Figure 1 As shown, the clamping device 100 may include: a drive / transmission unit 1, an arm 2, and a clamp 3. The drive / transmission unit 1 may include a housing and a drive or transmission device housed within the housing. In some embodiments, the drive device may include one or more motors. In some embodiments, such as Figure 1 As shown, the transmission device may include one or more couplings 6 for coupling with the drive motor and receiving power from the drive motor.

[0020] like Figure 1 As shown, the arm body 2 includes a proximal end 21 and a distal end 22. The proximal end 21 of the arm body 2 is connected to the drive / transmission unit 1, and the distal end 22 of the arm body 2 is connected to the clamp 3. In some embodiments, the clamp 3 may be fixedly connected to the distal end 22 of the arm body 2, or it may be movably connected to the distal end 22 of the arm body 2 via a wrist joint rotatable in one or more degrees of freedom. In some embodiments, the arm body 2 may be a flexible arm body, for example, including a continuous structure. The flexible arm body may be driven by the drive / transmission unit 1 to move in one or more degrees of freedom. For example, the drive / transmission unit 1 includes a linear transmission device (not shown) for converting rotational motion into linear motion. The linear transmission device converts the rotational motion received by the coupling 6 into linear motion to push or pull the drive wire of the arm body 2, thereby driving the arm body 2 to move and enabling the clamp 3 to achieve a specific pose. In some embodiments, the arm body 2 may be a rigid rod. The clamping device 100 may include a wrist joint movably connected to the distal end 22 of the arm body 2, such that the clamp 3 can rotate in one or more degrees of freedom.

[0021] Figure 2 A cross-sectional schematic diagram of a clamping device 100 according to some embodiments of the present disclosure is shown. For example... Figure 2As shown, the clamping device 100 includes a drive wire 4 for driving the clamp 3. The drive wire 4 is disposed inside the arm body 2 along the length direction of the arm body 2. The distal end of the drive wire 4 is connected to the clamp 3 for driving the opening and closing of the clamp 3. The proximal end of the drive wire 4 is connected to the drive / transmission unit 1. In some embodiments, the proximal end of the drive wire 4 is connected to a linear transmission device. The linear transmission device converts the rotational motion received by the coupling 6 into linear motion to push or pull the drive wire 4 in order to control the opening and closing of the clamp 3. For example, the linear transmission device pulls the drive wire 4 proximally, thereby driving the clamp 3 to decrease its opening angle. Conversely, the linear transmission device pushes the drive wire 4 distally, thereby driving the clamp 3 to increase its opening angle.

[0022] In some embodiments, the drive wire 4 is a deformable drive wire. The drive wire 4 has axial rigidity and can be subjected to axial pressure or tension and generate a reaction thrust or elastic force. The drive wire 4 may include an elastic material, such as a nickel-titanium alloy.

[0023] In some embodiments, the drive wire 4 can move axially proximally, pulling the clamp 3 so that the clamp 3's opening angle decreases, gradually approaching the target object. After the clamp 3 contacts the target object, the drive wire 4 can continue to move axially. If the target object is soft human tissue, the clamp 3's opening angle continues to decrease, and the drive wire 4 deforms (e.g., axially elongates), thereby applying a clamping force to the target object through the clamp 3. If the target object is a rigid object (e.g., surgical instruments, implants, etc.), the clamp 3's opening angle no longer decreases, the drive wire 4 deforms, and the clamp 3 applies a clamping force to the target object.

[0024] Figure 3(a) illustrates a method for determining a clamping device (e.g., according to some embodiments of the present disclosure). Figure 1-2 The flowchart illustrates a method 300 for applying clamping force to a gripping device 100 or clamp 3. Method 300 can be implemented or executed by hardware, software, or firmware. In some embodiments, method 300 can be implemented by a robot system (e.g., Figure 8 The surgical robot system 800 executes the method. In some embodiments, method 300 can be implemented as computer-readable instructions. These instructions can be read and executed by a general-purpose processor or a special-purpose processor. In some embodiments, these instructions can be stored on a computer-readable medium.

[0025] As shown in Figure 3(a), in step 301, the current of the drive motor used to drive the clamping device can be determined. The drive motor is used to drive the opening and closing of the clamping device. For example, the drive motor can push or pull a drive wire (e.g., drive wire 4), thereby driving the opening and closing of the clamps (e.g., clamps 3) of the clamping device. In some embodiments, the drive motor can be an external device relative to the clamping device 100. For example, the drive / transmission unit 1 of the clamping device 100 can include a transmission device. The drive motor can be coupled to one or more couplings 6 and drive the transmission device through the couplings 6. In some embodiments, the drive motor can be a built-in device of the clamping device 100. For example, the drive / transmission unit 1 can include a drive device. The drive device can include a drive motor for driving the drive wire 4 of the clamping device 100. The drive motor can be provided with a current sensor coupled thereto for detecting the current of the drive motor.

[0026] In some embodiments, method 300 may include receiving current from a drive motor (e.g., from a current sensor). In some embodiments, method 300 may include sending a current detection command to the current sensor and receiving the detected current from the current sensor. The current sensor may detect the current of the drive motor according to the current detection command. Alternatively, the current sensor may detect the current of the drive motor periodically or in real time.

[0027] In step 303, the determined current can be compared with the initial current. In this disclosure, the initial current refers to the current driving the drive motor of the clamping device when the clamping device is unloaded. In some embodiments, the deformation of the drive wire can be determined by the change in the current driving the drive motor of the clamping device. Figure 4 A time-current graph 400 is shown for a drive motor of a clamping device according to some embodiments of the present disclosure. It will be understood that graph 400 schematically illustrates the change in current over time as the motor drives the clamping device to close (e.g., clamp 3 to close). Figure 4 As shown, starting from time 0, the motor starts and pulls the drive wire (e.g. Figure 2 The drive wire 4) moves proximally, causing the clamping device to open at a smaller angle. For example, a motor can drive the coupling of the transmission mechanism (e.g., Figure 1 The coupling 6) rotates. The coupling drives the linear transmission device to move, thereby pulling the drive wire 4 to move closer to the end, reducing the opening angle of the clamp 3. Due to factors such as friction and transmission coefficient, a certain driving force is required to drive the clamp 3 to change its opening angle under no-load conditions. This is represented on curve 400 by the current remaining basically at the initial current I0 during this process. The clamp 3 is unloaded during this process, and the clamping force Fg is zero.

[0028] At time T0, clamp 3 contacts the target object as the opening angle decreases, while the motor continues to run (e.g., maintaining its original speed). Due to the presence of the target object, drive wire 4 begins to deform, and clamp 3 applies a clamping force to hold the target object. Figure 4 As shown in curve 400, starting from time T0, the motor's drive current increases from the initial current I0, the length of the drive wire 4 increases, and the clamping force of the clamp 3 also increases. At time T... t At that moment, the motor's drive current increases to I. t As the motor continues to run, the motor's drive current increases to its maximum value I. max And it remains at its maximum value. The deformation of the drive wire 4 also reaches its maximum, so the clamping force of the clamp 3 also reaches its peak.

[0029] In some embodiments, the current of the motor driving the clamping device is compared with the initial current I0. If the current of the motor driving the clamping device is greater than the initial current I0, it can be determined that the drive wire of the clamping device has deformed, and the clamp 3 applies a clamping force to the target object.

[0030] As shown in Figure 3(a), in step 305, the clamping force of the clamping device can be determined based on a comparison. Method 300 may include determining that the clamping force of the clamping device is zero in response to the determined current being less than or equal to the initial current. In this case, the clamping device is unloaded or not driven. Method 300 may also include determining that the clamping device has a clamping force in response to the determined current being greater than the initial current.

[0031] In some embodiments, the clamping force of the clamping device can be determined based on the relationship between the current of the drive motor and the clamping force of the clamping device. For example, the functional relationship between the current of the drive motor and the clamping force of the clamping device can be calculated or measured. The clamping force of the clamping device is calculated based on the current of the drive motor and this functional relationship. Alternatively, a lookup table of the correspondence between the current of the drive motor and the clamping force of the clamping device can be established by calculation, measurement, or interpolation. The clamping force of the clamping device can be determined based on the current of the drive motor using the lookup table.

[0032] In some embodiments, the clamping force of the clamping device can be determined by measuring the deformation of the drive wire of the clamping device. For example, at time t, the clamping force Fg of the clamping device (e.g., clamp 3) is... t The following formula can be used for calculation:

[0033] Fg t =k g ·F t (1)

[0034] Among them, F t Let k be the elastic force generated by the deformation of the driving wire (e.g., driving wire 4) at time t.g Let F be the transmission coefficient of clamp 3. The elastic force F of drive wire 4 at time t. t The following formula can be used for calculation:

[0035]

[0036] ΔL t =L t -L0 (3)

[0037] Where E is the elastic modulus of the driving wire 4, S is the cross-sectional area of ​​the driving wire 4, and ΔL t Let L be the deformation of driving wire 4 at time t, and L0 be the initial length of driving wire 4. t L is the length of the driving wire 4 at time t. In some embodiments, L t This can be obtained by detecting the deformation of the drive wire 4. Since the target object held by the clamp 3 may be soft human tissue, the deformation of the drive wire 4 can be determined by detecting the proximal and distal displacements of the drive wire 4.

[0038] Figure 3(b) illustrates a method for using a drive wire (e.g.) according to some embodiments of the present disclosure. Figure 2 The deformation of the drive wire 4) determines the clamping device (e.g. Figure 1-2 The flowchart illustrates a method 310 for applying the clamping force of a gripper 100 or clamp 3 in a robotic system. Method 310 can be implemented or executed by hardware, software, or firmware. In some embodiments, method 310 can be implemented by a robotic system (e.g., a mechanical device 100 or clamp 3). Figure 8 The surgical robot system 800 executes the procedure. In some embodiments, method 310 can be implemented as computer-readable instructions. These instructions can be read and executed by a general-purpose processor or a special-purpose processor. In some embodiments, these instructions can be stored on a computer-readable medium.

[0039] As shown in Figure 3(b), in step 311, the proximal displacement D of the drive wire of the clamping device can be determined. p In some embodiments, the drive motor of the gripper is configured with a stroke sensor to detect the motor's stroke. Method 310 may include receiving (e.g., from the stroke sensor) the stroke M of the drive motor of the gripper and calculating the proximal displacement D of the drive wire based on the stroke M. p The initial stroke of the drive motor (e.g., the stroke of the drive motor in its natural state when the clamping device is unloaded) can be set as M0, and at time t, the stroke of the drive motor is M. t The stroke variable of the drive motor can be calculated using the following formula:

[0040] ΔM=M t -M0 (4)

[0041] Due to the presence of mechanical transmission mechanisms (such as linear transmission devices), the motor stroke variable ΔM is related to the near-end displacement D. p There may be a transmission coefficient k between them. m Therefore, the proximal displacement D p The following formula can be used for calculation:

[0042] D p =k m ΔM (5)

[0043] In some embodiments, the drive / transmission unit 1 (e.g., a linear transmission device) may be equipped with a proximal displacement sensor for detecting the proximal displacement D of the drive wire. p For example, a linear transmission device may include a screw and a slider rotatably connected to the screw. The screw may be connected to a coupling 6 to rotate under the drive of the coupling 6. The rotation of the screw may drive the slider to slide linearly along the screw. A drive wire 4 is fixedly connected to the slider to move under the drive of the slider's linear sliding. In some embodiments, the proximal displacement sensor may be a stroke sensor coupled to the screw. Similar to the stroke sensor of the drive motor described above, the stroke sensor coupled to the screw can detect the stroke of the screw. Based on the detected screw travel, the proximal displacement D can be calculated using the transmission coefficient. p In some embodiments, the proximal displacement sensor may be a Hall sensor disposed in the drive / transmission unit 1. The slider may include a magnetic material and, during linear sliding along the screw, cuts the magnetic field of the Hall sensor. The Hall sensor can detect the stroke of the slider to obtain the proximal displacement D of the drive wire 4. p .

[0044] In step 313, the distal displacement D of the drive wire of the clamping device can be determined. d In some embodiments, during the operation of the clamping instrument, a vision module (e.g., an endoscope used during surgical procedures) captures images of the operation of the clamping instrument. Method 310 may include analyzing images of the clamping instrument (e.g., forceps head 3) and determining the distal displacement D of the drive wire. d For example, such as Figure 2 As shown, the two jaws of clamp 3 are hinged together, and the drive wire 4 can be hinged or fixedly connected to the hinge point of the two jaws of clamp 3. Method 310 may include analyzing an image of clamp 3 to identify the displacement of the hinge point, thereby obtaining the distal displacement D of the drive wire. d .

[0045] In some embodiments, the clamping device 100 may include a distal displacement sensor disposed on the clamp 3. For example, the distal displacement sensor may be a Hall sensor disposed on the clamp 3. Figure 2As shown, the connection points between the two jaws of the clamp 3 and the drive wire 4 may include magnetic material. During the movement of the drive wire 4, the magnetic material cuts the magnetic field of the Hall sensor. The Hall sensor can detect the travel of the connection points, thereby obtaining the distal displacement D of the drive wire 4. d Method 310 may include receiving a displacement value detected by a distal displacement sensor disposed on the clamp, and determining the distal displacement of the drive wire based on the detected displacement value.

[0046] Displacement D at the distal end of drive wire 4 d The detection is related to the structure of clamp 3. As an example, Figure 5 A perspective schematic diagram of another structure of the clamp 3 according to some embodiments of the present disclosure is shown. For example... Figure 5 As shown, the clamp 3 includes mating jaws 31 and 32. Jaws 31 and 32 are connected at a pivot point 33 by a pivot pin (not shown). The body of jaw 31 has a pair of grooves 35 on opposite sides, while the body of jaw 32 has a pair of grooves 36 on opposite sides that mate with the grooves 35 of jaw 31. A sliding pin 34 passes through the grooves 35 and 36 and is fixedly connected to a drive wire 4. The drive wire 4 can drive the sliding pin 34 to slide within the grooves 35 and 36 to control the opening and closing of the clamp 3.

[0047] Figure 6 A schematic cross-sectional view of the pliers head 32 according to some embodiments of the present disclosure is shown. Figure 6 As shown, the axis of the groove 36 of the jaw 32 forms an angle α with the extended plane of the clamping contact surface of the jaw 32. The axis of the groove 35 of the jaw 31 can be parallel to the extended plane of the clamping contact surface of the jaw 31. Therefore, when the sliding pin 34 slides in the grooves 35 and 36, different clamping angles of the jaws 3 can be achieved. The total variable stroke of the sliding pin 34 in the groove 36 is L. 20 The total variable stroke of sliding pin 34 within slide groove 35 is L. 10 At time t, the stroke of sliding pin 34 in slide groove 35 is denoted as D. 1t The stroke of sliding pin 34 in slide groove 36 is denoted as D. 2t .

[0048] In some embodiments, the travel D of the sliding pin 34 in the groove 36 is... 2t This can be obtained by analyzing the image of the sliding pin 36. Based on stroke D 2t The stroke D of sliding pin 34 in slide groove 35 can be calculated. 1t The stroke D of sliding pin 34 in slide groove 36 2t The stroke D of the slide 35 1t The relationship can be approximated by the following formula:

[0049] D1t =D 2t cosα (6)

[0050] Based on itinerary D 1t The distal displacement D of the driving wire 4 can be calculated. d For example, if the extension direction of the groove 35 is the same as the movement direction of the drive wire 4, then the distal displacement D d With itinerary D 1t Equal. If the extending direction of the groove 35 forms an angle β with the moving direction of the drive wire 4, then D d =D 1t cosβ.

[0051] In some embodiments, measurement can be performed using a sensor. Figure 5 The distal displacement of the drive wire 4 of the pliers head 3 is shown. Figure 7 A partial cross-sectional view of the clamp 3 according to some embodiments of the present disclosure is shown. Figure 7 As shown, the distal end of the drive wire 4 is fixedly connected to the slider 37. The slider 37 is fixedly connected to the sliding pin 34. The drive wire 4 drives the slider 37 to reciprocate, which in turn drives the sliding pin 34 to slide in the grooves 35 and 36, thereby controlling the opening and closing of the clamp 3. Figure 7 As shown, the clamp head 3 may include a Hall sensor 38. The slider 37 may include a magnetic material. During its movement, the slider 37 cuts the magnetic field of the Hall sensor 38. The Hall sensor 38 can detect the stroke of the slider 37, thereby obtaining the distal displacement D of the drive wire 4. d It should be understood that the clamping device 100 may not include the slider 37, or the slider 37 may not include magnetic material, while the sliding pin 34 may include magnetic material for use with the Hall sensor 38 to measure the distal displacement D of the drive wire 4. d .

[0052] Referring to Figure 3(b), in step 315, the elastic force of the drive wire of the clamping device can be calculated. For example, based on the proximal displacement D of the drive wire. p and distal displacement D d The deformation of the driving wire, ΔL = D, can be calculated. p -D d The elastic force of the driving wire can be calculated based on formula (2):

[0053]

[0054] In step 317, the clamping force of the clamping device can be calculated. For example, the clamping force of the clamping device can be calculated based on formulas (1) and (7).

[0055]

[0056] In some embodiments, the proximal displacement D of the driving wire p The clamping force of the clamping device at time t can be determined by detecting the stroke of the drive motor. Therefore, the clamping force of the clamping device at time t can be calculated using the following formula:

[0057]

[0058] In some embodiments, such as Figure 5-6 As shown, the stroke D of the sliding pin 34 in the slide groove 36 2t This can be obtained by analyzing the image of the sliding pin 36. Based on stroke D 2t The stroke D of the sliding pin 34 in the groove 35 can be calculated according to formula (6). 1t Displacement D at the distal end of the driving wire d With itinerary D 1t Under approximately equal conditions, the clamping force of the clamping device at time t can be calculated using the following formula:

[0059]

[0060] In some embodiments, by combining formulas (9) and (10), the clamping force of the clamping device at time t can be calculated according to the following formula:

[0061]

[0062] In some embodiments, method 300 may include (e.g., prompting an operator) indicating the clamping force Fg of the clamping device. t The clamping force Fg appears or is indicated. t The relative size (e.g., indicated by color indicator lights) or numerical value. The operator can adjust the operation based on the clamping force cues.

[0063] In some embodiments, method 300 may include maintaining the clamping force of the clamping device at its current value Fg based on (e.g., from an operator) a command to maintain the clamping force. t .

[0064] In some embodiments, method 300 may include applying a clamping force Fg to the clamping device. t With threshold Fg th A comparison is made. Method 300 may include if the clamping force Fg t Greater than the threshold Fg th An alarm signal is issued. Method 300 may further include if the clamping force Fg t Greater than the threshold Fg th Maintain the clamping force of the clamping device at its current value Fg tSince the target object may be human tissue, excessive clamping force can cause damage to the tissue. Alarm signals or clamping force maintenance can mitigate injuries caused by operator error.

[0065] In some embodiments, method 300 may be executed periodically to provide clamping force periodically, or executed in real time to provide clamping force in real time.

[0066] Figure 8 A schematic diagram of a surgical robot system 800 according to some embodiments of the present disclosure is shown. Figure 8 As shown, the surgical robot system 800 may include at least one carriage 10, at least one positioning arm 5, and at least one surgical instrument. At least one positioning arm 5 may be connected to the carriage 10. At least one surgical instrument may be detachably connected to the distal end of the positioning arm 5. The surgical instrument may include surgical tools (e.g., clamping instrument 100) or an endoscope. The clamping instrument 100 may include a drive / transmission unit 1, an arm body 2, a clamp 3, and a drive wire 4 (…). Figure 8 (Not shown in the image).

[0067] In some embodiments, the surgical robot system 800 may include a processor for performing methods according to some embodiments of the present disclosure, such as method 300 shown in FIG. 3(a) or method 310 shown in FIG. 3(b). For example, the surgical robot system 800 may include a memory for storing instructions and a processor coupled to the memory. The processor may execute the instructions stored in the memory to perform methods according to some embodiments of the present disclosure, such as method 300 shown in FIG. 3(a) or method 310 shown in FIG. 3(b).

[0068] In some embodiments, the surgical robot system 800 may include a current sensor coupled to a drive motor of a gripper instrument for detecting the current in the drive motor. A processor of the surgical robot system 800 may compare the current detected by the current sensor with an initial current. If the detected current is greater than the initial current, the processor may determine that the drive wire of the gripper instrument has deformed and has a gripping force. If the detected current is less than or equal to the initial current, the processor may determine that the gripper instrument has no gripping force.

[0069] In some embodiments, the surgical robot system 800 may include a stroke sensor coupled to a drive motor of a gripping instrument for detecting the stroke of the drive motor. The processor of the surgical robot system 800 may calculate the proximal displacement D of the drive wire based on the stroke detected by the stroke sensor. p .

[0070] In some embodiments, the drive / transmission unit 1 may include a linear transmission device. The linear transmission device may include a screw and a slider rotatably connected to the screw. The screw may be connected to a (built-in or external) drive motor to rotate under the drive of the drive motor. The rotation of the screw can drive the slider to slide linearly along the screw. The drive wire 4 is fixedly connected to the slider to move under the drive of the slider's linear sliding. In some embodiments, the proximal displacement sensor may be a stroke sensor coupled to the screw. The processor may calculate the proximal displacement D based on the screw stroke detected by the stroke sensor coupled to the screw. p In some embodiments, the proximal displacement sensor may be a Hall sensor disposed in the drive / transmission unit 1. The slider may include a magnetic material and, during linear sliding along the screw, cuts the magnetic field of the Hall sensor. The Hall sensor can detect the stroke of the slider to obtain the proximal displacement D of the drive wire 4. p .

[0071] In some embodiments, the surgical robot system 800 may include an endoscope for capturing images of a gripping instrument. The processor can analyze the images of the gripping instrument to determine the distal displacement D of the drive wire. d For example, the processor can identify the displacement of the connecting pins of the two jaws of clamp 3 in an image and calculate the distal displacement D of the drive wire. d .

[0072] In some embodiments, the clamping device 100 may include a distal displacement sensor disposed on the clamp 3. For example, the distal displacement sensor may be a Hall sensor disposed on the clamp 3. The connection point, slider, or sliding pin connected to the drive wire 4 may include a magnetic material. During the movement of the drive wire 4, the magnetic material cuts the magnetic field of the Hall sensor. The Hall sensor can detect the travel of the magnetic material, thereby obtaining the distal displacement D of the drive wire 4. d .

[0073] In some embodiments, the processor of the surgical robot system 800 can be based on the proximal displacement D of the drive wire. p and distal displacement D d Calculate the clamping force of the clamping device.

[0074] In some embodiments, the surgical robot system 800 includes an output unit (not shown), such as a display. The output unit can provide the operator with a representation of the clamping force of the clamping instrument, such as a visual color display, a visual numerical display, mechanical vibration, etc.

[0075] In some embodiments, the surgical robot system 800 includes an input unit (not shown) for receiving operating instructions from an operator. The processor can increase or decrease the clamping force of the clamp 3 by controlling a drive motor based on instructions received from the operator to increase or decrease the clamping force of the clamp 3. The processor can also maintain the clamping force of the clamping instrument at its current value Fg based on instructions to maintain the clamping force. t .

[0076] In some embodiments, the processor can control the clamping force Fg of the clamping device. t With threshold Fg th Compare. If the clamping force Fg t Greater than the threshold Fg th The processor can issue an alarm signal, or it can maintain the clamping force of the clamping device at the current value Fg. t This prevents damage to human tissue caused by excessive clamping force if the target object is human tissue. In some embodiments, the alarm signal for excessive clamping force may include a change in the color of the clamp image 3 on the display. For example, green indicates normal clamping force, while red indicates that the clamping force exceeds a threshold and may cause damage to the target object.

[0077] Some embodiments of this disclosure can improve the accuracy of clamping force detection of clamping instruments. Furthermore, some embodiments of this disclosure can also improve the operational stability and accuracy of surgical robots, thereby enhancing the safety of surgical procedures. In some embodiments of this disclosure, the presence of clamping force in the clamping instrument is determined by the current of the drive motor of the clamping instrument. When the clamping instrument has no clamping force, there is no need to detect the deformation of the drive wire. This avoids frequent detection of the drive wire deformation, simplifying operation and saving resources. Moreover, in some embodiments, the clamping force can be determined based on the relationship between the current of the drive motor and the clamping force of the clamping instrument, thus reducing detection operations and even eliminating the need for sensors, simplifying the structure of the clamping instrument and surgical robot system, and reducing the manufacturing cost of the clamping instrument and surgical robot.

[0078] Those skilled in the art should understand that this disclosure is not limited to the exemplary embodiments described above. Various changes, adjustments, and substitutions can be made by those skilled in the art without departing from the scope of this disclosure. Therefore, further equivalent embodiments may be included without departing from the concept of this disclosure, and the scope of this disclosure is determined by the scope of the appended claims.

Claims

1. A computer-readable medium having stored thereon instructions which, when executed by a processor, cause a computer to execute a method for determining a clamping force of a clamping instrument, characterized in that, The method includes: Obtain current for a drive motor to drive the clamping device, the drive motor being connected to a drive wire of the clamping device to drive the clamping device to open and close via the drive wire, wherein the drive wire comprises a nickel-titanium alloy wire; and The clamping force of the clamping device is determined in response to the current of the drive motor being greater than the initial current of the drive motor. The method further includes: Obtain the proximal displacement of the drive wire; Obtain the distal displacement of the drive wire; The elastic force of the driving wire is determined based on its proximal and distal displacements; and The clamping force of the clamping device is determined based on the elasticity of the drive wire.

2. The computer-readable medium of claim 1, wherein, The method further includes: Receive the stroke of the drive motor; and Based on the travel distance and the initial travel distance of the drive motor, the proximal displacement of the drive wire is calculated.

3. The computer-readable medium of claim 1, wherein, The method further includes: The proximal displacement of the drive wire is received by the sensor.

4. The computer-readable medium of claim 1, wherein, The method further includes: Analyze the image of the clamping device; and Based on the analysis, the distal displacement of the drive wire is determined.

5. The computer-readable medium of claim 1, wherein, The method further includes: Receives a displacement value detected by a distal displacement sensor disposed on the clamp of the clamping device, the drive wire being connected to the clamp to drive the clamp to open and close; and Based on the displacement value, the distal displacement of the drive wire is determined.

6. The computer-readable medium of any of claims 1-5, wherein, The method further includes: The clamping force of the clamping device is indicated or the relative magnitude of the clamping force is displayed; and / or Based on the instruction to maintain the clamping force, the clamping force of the clamping device is maintained at its current value.

7. The computer readable medium of any of claims 1-5, wherein, The method also includes displaying the numerical value of the clamping force.

8. The computer-readable medium of any one of claims 1-5, wherein, The method further includes: Compare the clamping force of the clamping device with a threshold; and In response to the clamping force being greater than the threshold, an alarm signal is issued and / or the clamping force is maintained at the current value.

9. A surgical robot system, comprising: At least one vehicle; At least one positioning arm is connected to the at least one trolley; At least one surgical instrument is detachably connected to the distal end of the at least one positioning arm, the at least one surgical instrument including a clamping device, the clamping device including a clamp and a drive wire for driving the clamp to open and close; as well as A processor is configured to perform a method for determining the clamping force of the clamping device, the method comprising: Obtain current for a drive motor to drive the clamping device, the drive motor being connected to a drive wire of the clamping device to drive the clamping device to open and close via the drive wire, wherein the drive wire comprises a nickel-titanium alloy wire; and The clamping force of the clamping device is determined in response to the current of the drive motor being greater than the initial current of the drive motor. The method further includes: Obtain the proximal displacement of the drive wire; Obtain the distal displacement of the drive wire; The elastic force of the driving wire is determined based on its proximal and distal displacements; and The clamping force of the clamping device is determined based on the elasticity of the drive wire.

10. The surgical robotic system of claim 9, wherein, The method further includes: Receive the stroke of the drive motor; and Based on the travel distance and the initial travel distance of the drive motor, the proximal displacement of the drive wire is calculated.

11. The surgical robotic system of claim 9, wherein, The method further includes: The proximal displacement of the drive wire is received by the sensor.

12. The surgical robotic system of claim 9, wherein, The method further includes: Analyze the image of the clamping device; and Based on the analysis, the distal displacement of the drive wire is determined.

13. The surgical robotic system of claim 9, wherein, The method further includes: Receives a displacement value detected by a distal displacement sensor disposed on the clamp of the clamping device, the drive wire being connected to the clamp to drive the clamp to open and close; and Based on the displacement value, the distal displacement of the drive wire is determined.

14. The surgical robot system as described in any one of claims 9-13, characterized in that, The method further includes: The clamping force of the clamping device is indicated or the relative magnitude of the clamping force is displayed; and / or Based on the instruction to maintain the clamping force, the clamping force of the clamping device is maintained at its current value.

15. The surgical robot system as described in any one of claims 9-13, characterized in that, The method also includes displaying the numerical value of the clamping force.

16. The surgical robot system as described in any one of claims 9-13, characterized in that, The method further includes: Compare the clamping force of the clamping device with a threshold; and In response to the clamping force being greater than the threshold, an alarm signal is issued and / or the clamping force is maintained at the current value.

17. The surgical robot system as claimed in claim 9, characterized in that, Also includes: A current sensor, coupled to the drive motor of the clamping device, is used to detect the current of the drive motor; and / or A stroke sensor, coupled to the drive motor of the clamping device, is used to detect the stroke of the drive motor.

18. The surgical robot system as claimed in claim 9, characterized in that, The clamping device also includes: A drive transmission unit includes a linear transmission device, the linear transmission device comprising a screw and a slider rotatably connected to the screw, the drive wire being fixedly connected to the slider; and A stroke sensor, coupled to the screw, is used to detect the stroke of the screw, and the processor is used to calculate the proximal displacement of the drive wire based on the detected screw stroke; or A Hall sensor, disposed in the drive transmission unit, is used to detect the stroke of the slider, the slider comprising a magnetic material.

19. The surgical robot system as claimed in claim 9, characterized in that, The at least one surgical instrument includes an endoscope for taking images of the clamping instrument.

20. The surgical robot system as described in claim 19, characterized in that, The clamps include: The first clamp head includes a first sliding groove; A second jaw, rotatably connected to the first jaw and including a second groove that mates with the first groove; and A sliding pin is fixedly connected to the drive wire and can slide within the first and second sliding grooves. The processor is used to determine the stroke of the sliding pin in the second groove based on the captured image, and to calculate the distal displacement of the drive wire based on the stroke of the sliding pin in the second groove.

21. The surgical robot system as described in claim 9, characterized in that, The clamping device includes a Hall sensor mounted on the clamp for detecting the distal displacement of the drive wire, and the connection point, slider, or sliding pin connected to the distal end of the drive wire is made of magnetic material.

22. The surgical robot system as claimed in claim 9, characterized in that, Also includes: The output unit is used to provide a representation of the clamping force of the clamping device; or An input unit is used to receive operation instructions. The processor is used to increase or decrease the clamping force of the clamp by controlling the drive motor of the clamping device based on the operation instructions, or the processor is used to maintain the clamping force of the clamp at a current value based on an operation instruction to maintain the clamping force.

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