CN2855353Y - Operation piloting tool - Google Patents

Abstract

The utility model belongs to the technical field of computer-assisted surgical navigation, in particular to a surgical navigation tool in a computer-assisted surgical navigation system. The utility model designs a set of articulated manipulators with 5 degrees of freedom on the basis of using an optical positioning and tracking system to detect the spatial position of surgical navigation tools. The manipulator adopts a four-stage transmission mechanism, and each transmission mechanism adopts a self-locking worm gear transmission pair, which has a stable instantaneous transmission ratio and high transmission accuracy. Through the transmission between the joints, the guide template at the end is driven to move in three dimensions in space, and can accurately reach the position of the surgical target, providing precise positioning and guidance for the doctor's operation. The small and compact mechanical structure of the utility model makes the operation more flexible and convenient, and avoids the problem of shaking, and plays an important role in improving the accuracy of the operation, reducing the trauma of the operation, and improving the success rate of the operation.

Description

A Surgical Navigation Tool

technical field

The utility model belongs to the technical field of computer surgical navigation, in particular to a surgical guide tool in a computer-aided surgical navigation system.

Background technique

The current surgical navigation system can be divided into active structure and passive structure according to the interaction mode of surgical tools and surgical environment. The active structure mainly refers to the surgical robot, which can perform precise surgical operations according to the surgical plan without the manual intervention of doctors. However, surgical robots are mostly improved from industrial robots. Their high strength and rigidity requirements make their structures too large compared to the surgical space, and it is often difficult to meet the complexity requirements of surgery in terms of flexibility. There are sufficient security measures to protect doctors and patients from possible misuse risks.

At present, most surgical navigation adopts a passive structure, which completely abandons the robot structure, uses an optical positioning system as a detection instrument, and fixes light-emitting balls or light-emitting diodes on traditional surgical tools or prosthesis installation templates. Real-time interaction of images. This structure has aroused the interest of surgeons as soon as it came out. It fully respects the doctor's dominant position in the operation. The entire operation is still performed and judged by the doctor. As an auxiliary device, the navigation system only plays the role of an assistant. .

However, the current surgical navigation system is not perfect. The outstanding problem is that it adopts a hand-held structure mode, and the human hand tends to vibrate the surgical tools due to fatigue when the operation time is long. It has been tested and measured that when the surgical tool is in a hand-held state, the amount of vibration drift is generally between 0.5 and 1.0 mm. This phenomenon directly affects the detection accuracy of the surgical tool by the optical positioning system, resulting in positioning and guiding errors of the surgical tool during the operation, thereby affecting the accuracy of the entire operation.

In short, traditional surgical robots have high positioning accuracy and processing accuracy, but are bulky and not flexible enough. The current surgical navigation system is obviously superior to surgical robots in terms of flexibility and safety, and has high operability, but it has certain defects in the accuracy of surgery, especially it is difficult to solve the shaking of hand-held surgical tools question.

Contents of the invention

The purpose of the utility model is to design a new type of surgical navigation tool that not only has high positioning accuracy, but also has good flexibility and safety.

Aiming at the deficiencies and defects of the traditional surgical robot and the existing navigation system, the utility model proposes a new type of surgical navigation tool, which is a manipulator with 5 degrees of freedom designed on the basis of using an optical positioning tracking system to detect the spatial position . It can be called a hand-eye navigation structure, the optical positioning system is equivalent to the "eye", and the manipulator is naturally equivalent to the "hand". Among them, the optical positioning tracking system can be used to detect the spatial position of the navigation tool and locate it.

The manipulator has two functions: ① positioning the end of the wrist or surgical instruments to the surgical site; ② guiding the surgical instruments so that they can reach the surgical target precisely.

In the design of the manipulator, the utility model follows the following principles: ①It occupies a small space and does not interfere with the operation space; ②It can be locked at any position; ③It is a balance mechanism. According to these three requirements, the utility model adopts the structural form of three rotating joints for adjoining, which has the characteristics of small size, large working space, high positioning accuracy and strong intuitive movement. The utility model adopts a four-stage transmission mechanism, and each transmission mechanism adopts a worm gear transmission pair with a self-locking function, which has a stable instantaneous transmission ratio and high transmission accuracy.

Since the overall structure of the manipulator is connected to the patient's surgical site through a clamping device, or a 6V miniature DC servo motor, a planetary gear reducer with a proper reduction ratio is built in to increase the driving torque, and an external 1000-line encoder realizes servo motor and control. Information feedback between devices.

In the utility model, the first-stage transmission of the manipulator is manual, including: a housing, a worm, a worm wheel, a locking screw, a manual nut, two rolling bearings and a bearing cover. The connection method is as follows: the worm is connected to the housing through rolling bearings, the manual nut is connected to the output shaft of the worm through fixing screws; the worm gear is connected to the housing through rolling bearings, and the meshing transmission with the worm is realized, and the locking screw is screwed on the threaded hole of the housing , the worm gear can be locked.

The second-stage transmission, the third-stage transmission and the fourth-stage transmission of the manipulator have the same transmission structure and connection mode. Mainly include: housing, servo motor, worm, worm gear, 2 rolling bearings, bearing cover. The connection method is as follows: the motor is fixed inside the casing, the motor shaft and the worm are fixed by screws, and the worm wheel is fixed in the casing by two bearings to realize the meshing with the worm.

The transmissions of all stages are connected together by couplings.

The end of the manipulator is the guide template, which can drive the guide template to rotate freely within 360 degrees through the output shaft of the fourth stage transmission. Optical positioning marks are installed on the guide template, so the spatial position of the guide template can be obtained through the optical positioning system, which makes up for the cumulative error between the various transmission systems.

Through the transmission between the joints, the guide template can be driven to realize three-dimensional movement in space, and can accurately reach the ideal position, providing precise positioning and guidance for the surgeon's operation.

The small and compact mechanical structure of the utility model makes the surgical operation more flexible and convenient compared with the traditional surgical robot, and solves the vibration problem existing in the current surgical navigation tools. , shortening the postoperative recovery period of patients has played a very important role.

Description of drawings

Fig. 1 is a schematic diagram of the working principle of the utility model.

Figure 2 System control schematic diagram.

Fig. 3 is a structural schematic diagram of the utility model.

Numbers in the figure: 1 is the shell, 2 is the worm, 3 is the worm wheel, 4 is the motor, 5 is the worm wheel, 6 is the worm, 7 is the motor, 8 is the shell, 9 is the shell, 10 is the motor, 11 is the coupling Shaft device, 12 is the housing, 13 is the worm, 14 is the worm wheel, 15 is the locking screw, 17 is the worm wheel, 18 is the end guide plate; 19 is the optical positioning tracking system, 20 is the surgical navigation tool, 2 is the optical tracking mark, 22 is an intramedullary nail, and 23 is a holding tool.

Detailed ways

As shown in Fig. 1, label 20 (inside the dotted line) is the surgical navigation tool of the present invention, and its implementation cannot be separated from the optical positioning and tracking system 19, the optical tracking marker 21, the clamping tool 23 and the surgical prosthesis. Taking the intramedullary nail 22 implantation operation as an example, it has a certain bending deformation during insertion into the curved bone marrow cavity of the patient, which causes the shape deformation and position shift of the locking nail hole at the distal end of the intramedullary nail, resulting in the locking nail Insertion is very difficult. With the help of the optical positioning tracking system 19 and the X-ray image of the mobile C-arm in the operating room, the positional relationship of the keyhole at the distal end of the intramedullary nail relative to the navigation tool 20 can be determined, and the ideal position of the guide plate at the end of the manipulator can be obtained. According to the conversion relationship between the current position of the guide plate and its ideal position, the motion parameters of each joint of the navigation tool can be determined. Each joint moves according to the corresponding motion parameters. After it is in place, you can check whether the surgical tool has reached the required orientation by marking the position information on the end guide. If there is a deviation, the deviation information can be fed back to the control system to continue to drive the movement of each joint until the guide plate reaches the expected position.

The system uses an optical positioning and tracking system, so the control structure of the system has two feedback loops of inner and outer loops. Figure 2 is the control schematic diagram of the whole system. The control structure inside the dotted line is the same as the traditional control structure, forming internal feedback; outside the dotted line, the spatial position information of the end guide plate is fed back through the optical positioning tracking system, and it is consistent with the expected position information. Make comparisons to form external feedback.

Fig. 3 is a schematic diagram of the mechanical structure of the utility model, which is divided into a first-stage transmission mechanism, a second-stage transmission mechanism, a third-stage transmission mechanism and a fourth-stage transmission mechanism. In the first-stage transmission mechanism, the worm 13 and the worm wheel 14 are connected together with the housing 12 through bearings, and the locking screw 15 can lock the worm wheel manually. The output shaft of the worm gear is connected with the housing 9 of the second-stage transmission mechanism through a shaft coupling 11 .

In the second-stage transmission mechanism, the servo geared motor 10 with encoder is fixed on the housing 9, the worm 16 is fixed on the output shaft of the motor 10, and is meshed with the worm wheel 17, and the worm wheel 17 is connected to the housing 9 through the bearing. connected together. The worm wheel output shaft of the second-stage transmission mechanism is connected with the housing 8 of the third-stage transmission mechanism through a shaft coupling.

In the third-stage transmission mechanism, the servo deceleration motor 7 with encoder is fixed on the housing 8, the worm 6 is fixed on the output shaft of the motor 7, and is meshed with the worm gear 5, and the worm gear 5 is connected to the housing 8 through the bearing. connected together. The worm gear output shaft of the third-stage transmission mechanism is connected with the housing 1 of the fourth-stage transmission mechanism through a coupling.

In the fourth-stage transmission mechanism, the servo reduction motor 4 with encoder is fixed on the casing 1, the worm 2 is fixed on the output shaft of the motor 4, and is meshed with the worm wheel 3, and the worm wheel 3 is connected to the casing 1 through a bearing. together. The end guide plate 18 is directly fixed on the worm wheel output shaft of the fourth-stage transmission mechanism.

In the above structure, the servo motor can adopt a 6V miniature DC servo motor.

Claims (2)

1. A surgical navigation tool, characterized in that it is a manipulator with 5 degrees of freedom, wherein the manipulator adopts a 4-stage transmission mechanism, and each stage of the transmission mechanism adopts a miniature DC servo motor, a built-in planetary gear reducer, and an external connection of 1000 The linear encoder realizes the information feedback between the servo motor and the controller. 2. The surgical navigation tool according to claim 1, characterized in that the connection mode of the first-stage transmission mechanism of the manipulator is as follows: the worm is connected to the housing through rolling bearings, the manual nut is connected to the output shaft of the worm through fixing screws; the worm wheel is connected through The rolling bearing is connected with the housing, and is meshed with the worm for transmission. The locking screw is screwed into the threaded hole of the housing to lock the worm gear; Transmission structure and connection mode: the servo motor is fixed inside the casing, the servo motor shaft and the worm are fixed by screws, the worm wheel is fixed in the casing through two bearings, and realizes the meshing with the worm, the end of the manipulator is a guide template, through the first The output shaft of the four-stage transmission drives the guide template to rotate freely within 360 degrees, and the guide template is equipped with optical positioning marks.

Images