Background
In recent years, with the rapid development of sensor technology, computer technology and control technology, the application of robot technology in combination with various technologies such as sensors and medical images in the medical service industry becomes a hot spot for research of many scholars at home and abroad. The minimally invasive vascular interventional surgical robot is a typical representative of medical robots, and the attention of people to the surgical treatment field is increasing day by day, which also makes the minimally invasive interventional surgical robot one of the hot topics in the international robot research field.
Most of vascular interventional surgical robot systems adopt a master-slave structure, and doctors control force feedback hand controllers or operating rods and the like at a master end to control the motion of a slave end catheter. The interaction force information detected by the sensor needs to be converted by the main hand to be sensed by the operator, and the force feedback information expected to be sensed by the operator is interfered by the influence of the dynamic performance of the main hand. The doctor can not really sense the force information received by the catheter as in the traditional operation, and the safety of the operation is not improved.
Based on the force feedback function, the blood vessel interventional operation robot system with the force feedback function is independently researched and designed in China. The system still employs a master-slave configuration for the physician's own safety considerations, keeping the physician away from the X-ray radiation. The physician can directly manipulate the catheter on the master end manipulator and remotely control the motion of the slave end catheter by using teleoperation technology. The slave controller feeds back the acquired force information of the slave catheter to the master end in a current form, and the master operator realizes force feedback by using the electromagnetic induction principle, so that a doctor can sense resistance information received by the advancing of the catheter. Meanwhile, a doctor can monitor the condition of the slave catheter through a high-definition image and a multi-dimensional information monitoring interface and perform operation according to tactile and visual feedback information.
However, in the prior art, the existing vascular robot, structure and control system still intervene the blood vessel through the catheter from the end, so that the blood vessel is easily damaged when the catheter collides with the blood vessel. Therefore, in the prior art, a micro-robot is also used, and the navigation path of the micro-robot is controlled by a robust control motion controller.
However, the blood components and concentration in the blood vessel, and the thickness and venation of the blood vessel network are different, so that the positioning, the track and the operation control precision of the micro robot in the blood vessel are not in an ideal state.
Disclosure of Invention
In view of the above, the present invention provides a control system and method for a vascular robot based on autonomous control.
A control method of a vascular robot based on autonomous control comprises the following steps:
s1, obtaining original blood vessel image information obtained by CT scanning, and drawing the original blood vessel image information into a three-dimensional blood vessel skeleton network image; generating robot navigation path information according to the three-dimensional blood vessel skeleton network image;
s2, generating first advance control information of the vascular robot according to the acquired intravascular blood density information, the vascular robot attribute information and the navigation path information, and controlling the vascular robot to advance through the first advance control information;
s3, pressure information sent back by the vascular robot is obtained in real time, whether the pressure information exceeds a first alarm threshold value or not is judged, and when the pressure information exceeds the first alarm threshold value, the first forward control information is adjusted to obtain second forward control information;
and S4, judging whether the vascular robot reaches the preset virtual position or not according to the robot navigation path information, checking the preset position according to the CT scanning result when the vascular robot reaches the preset virtual position, and determining that the vascular robot reaches the preset position when the checking is passed.
In the control method of the vascular robot based on autonomous control according to the present invention,
the step S1 further includes:
and segmenting the running track of the robot according to the three-dimensional blood vessel skeleton network image and the navigation coordinate information, and setting time threshold slice information of each segment.
In the control method of the vascular robot based on autonomous control according to the present invention,
after segmenting the travel track of the robot and setting time threshold slice information of each segment, the method further comprises the following steps:
and respectively setting speed threshold information of time threshold slice information of each segment according to the vessel diameter and path bifurcation information in the three-dimensional blood vessel skeleton network image.
In the control method of the vascular robot based on autonomous control according to the present invention,
in step S3, acquiring pressure information sent back by the vascular robot in real time, and before determining whether the pressure information exceeds a first alarm threshold, the method further includes:
judging whether the speed of the robot in the current segment is greater than the corresponding speed threshold information or not, and if so, adjusting the first forward control information to obtain the corrected first forward control information; accordingly, the number of the first and second electrodes,
continuously executing real-time acquisition of pressure information returned by the vascular robot, judging whether the pressure information exceeds a first alarm threshold value, and adjusting the corrected first forward control information to obtain second forward control information when the pressure information exceeds the first alarm threshold value;
and when the speed is less than or equal to the corresponding speed threshold value information, continuously acquiring pressure information returned by the vascular robot in real time, judging whether the pressure information exceeds a first alarm threshold value, and when the pressure information exceeds the first alarm threshold value, adjusting the first forward control information to obtain second forward control information.
The invention also provides a control system of the vascular robot based on the autonomous control, which executes the steps of the control method of the vascular robot based on the autonomous control.
The beneficial technical effects are as follows: compared with the prior art, the invention can realize that: the control information of the vascular robot can accurately control the moving speed and position of the vascular robot by generating the navigation path information of the vascular robot based on the three-dimensional vascular network image; whether the pressure information transmitted back by the vascular robot exceeds a preset alarm threshold value or not is set, so that the vascular robot is not damaged by overlarge pressure when in operation; and the invention is different from the way of controlling the positioning of the robot without a catheter, the invention judges whether the vascular robot reaches the preset virtual position or not through the navigation path information of the robot, when the vascular robot reaches the preset virtual position, the preset position is checked according to the CT scanning result, and when the check is passed, the vascular robot is determined to reach the preset position, thereby ensuring that the robot can reach the required position.
Detailed Description
As shown in fig. 1, in an embodiment of the present invention, a control method of a vascular robot based on autonomous control includes the following steps:
s1, obtaining original blood vessel image information obtained by CT scanning, and drawing the original blood vessel image information into a three-dimensional blood vessel skeleton network image; and generating robot navigation path information according to the three-dimensional blood vessel skeleton network image.
Alternatively,
the step S1 further includes:
and segmenting the running track of the robot according to the three-dimensional blood vessel skeleton network image and the navigation coordinate information, and setting time threshold slice information of each segment.
In the embodiment of the invention, the three-dimensional blood vessel skeleton network image comprises the caliber of a blood vessel, blood vessel intersection information and curvature information inside the blood vessel. The blood vessel crossing information refers to the bifurcation of a blood vessel, generally, the blood vessel is divided into two parts, and when the bifurcation is met, the information of the caliber and the curvature of the general blood vessel can be changed.
Optionally, the generating of the robot navigation path information according to the three-dimensional blood vessel skeleton network image includes establishing a virtual coordinate system of the three-dimensional blood vessel skeleton, where the virtual coordinate system is established in the following manner:
selecting the center on the tube surface as an origin, generating a translation vector through the radius of the tube surface and the origin, obtaining the coordinates of an initial point according to the translation vector and the rotation degree of a vector along the normal of the section, and obtaining a data set A of coordinates of each point on the tube surface by analogy;
and another tube surface center is selected as another origin, and a data set B is generated by the method; and generating a preset blood vessel distance section through the data set A and the data set B.
Determining an angle θ between adjacent preset vessel distance segments and generating the following expression representing the position coordinates:
wherein x, y and z are three directional axes corresponding to the three-dimensional coordinate system respectively; l is the length of the preset blood vessel distance section,
is the change in azimuth angle in the x-axis direction. Through the expression, the robot navigation control index can be digitalized, and the robot navigation can be better served.
Through the expression, the position information of the robot in the blood vessel can be obtained through calculation, the change information of the diameter and the curvature of the blood vessel can be obtained through the change of the angle, and whether the bifurcation of the path occurs or not can be obtained. The tube surface is the section of the blood vessel, and the origin is the circle center position corresponding to the section.
In the control method of the vascular robot based on autonomous control according to the present invention,
after segmenting the travel track of the robot and setting time threshold slice information of each segment, the method further comprises the following steps:
and respectively setting speed threshold information of time threshold slice information of each segment according to the vessel diameter and path bifurcation information in the three-dimensional blood vessel skeleton network image.
Reconstructing a coordinate expression, and dividing a three-dimensional blood vessel skeleton network into a straight section, a variable section, a bent section, a crossed section and a composite section, wherein the straight section is a section of blood vessel of which the pipe diameter change does not exceed a preset value; the change section is a section of blood vessel with the diameter change of the blood vessel exceeding a preset value; the bending section is a section of the blood vessel with the bending of the blood vessel exceeding a preset value; the cross section is a section of blood vessel with a bifurcation of the blood vessel appearance path; the composite section is a section of blood vessel comprising two or more changes of pipe diameter, bending and crossing.
The speed threshold information of the time threshold slice information of each segment is respectively set according to the divided straight segment, the divided change segment, the divided bent segment, the divided cross segment and the divided composite segment, the speed threshold information aims to accurately control the motion direction and the speed information of the robot in the blood vessel, and the reason is that when the pipe diameter, the movement direction and the movement speed information of the robot in the blood vessel are changed, the pressure information returned by the robot cannot necessarily completely reflect the actual pressure caused by the robot in the blood vessel, for example, the contact surface and the contact angle between a sensor and the inner wall of the blood vessel are changed, the value cannot truly reflect the pressure, and the injury of the blood vessel is avoided to the maximum extent.
S2, generating first advance control information of the vascular robot according to the acquired intravascular blood density information, the vascular robot attribute information and the navigation path information, and controlling the vascular robot to advance through the first advance control information;
the significance of the step is that the advancing control information can control the advancing direction of the robot more accurately by considering the influence of the blood density information on the advancing of the robot and the position of the contact surface of the robot and the blood vessel measured by the size and the shape of the robot and the sensor.
Optionally, the acceleration information in the first forward control information is as follows:
wherein c is a blood retardation coefficient, rho is blood density information, v is velocity information of the robot relative to blood flow, A is contact area information of the robot advancing section and the blood, m is quality information of the robot, and f (t) is a time-based compensation coefficient.
By controlling the acceleration information in the first forward control information, the speed of the robot can be accurately controlled.
And S3, acquiring pressure information transmitted back by the vascular robot in real time, judging whether the pressure information exceeds a first alarm threshold value, and adjusting the first forward control information to obtain second forward control information when the pressure information exceeds the first alarm threshold value.
Optionally, withdrawal control information may be set, so as to perform a withdrawal operation on the robot when pressure information returned by the vascular robot exceeds a second alarm threshold, where the second alarm threshold is greater than the first alarm threshold, so as to avoid that the pressure value alarm affects the complete execution of the operation, and the robot may withdraw in advance when the second alarm threshold is exceeded, and after the safety is confirmed and the control information is adjusted, the subsequent operation is continuously performed.
Alternatively,
in step S3, acquiring pressure information sent back by the vascular robot in real time, and before determining whether the pressure information exceeds a first alarm threshold, the method further includes:
judging whether the speed of the robot in the current segment is greater than the corresponding speed threshold information or not, and if so, adjusting the first forward control information to obtain the corrected first forward control information; accordingly, the number of the first and second electrodes,
continuously executing real-time acquisition of pressure information returned by the vascular robot, judging whether the pressure information exceeds a first alarm threshold value, and adjusting the corrected first forward control information to obtain second forward control information when the pressure information exceeds the first alarm threshold value;
and when the speed is less than or equal to the corresponding speed threshold value information, continuously acquiring pressure information returned by the vascular robot in real time, judging whether the pressure information exceeds a first alarm threshold value, and when the pressure information exceeds the first alarm threshold value, adjusting the first forward control information to obtain second forward control information.
And S4, judging whether the vascular robot reaches the preset virtual position or not according to the robot navigation path information, checking the preset position according to the CT scanning result when the vascular robot reaches the preset virtual position, and determining that the vascular robot reaches the preset position when the checking is passed.
The significance of the step is that the information of the robot position obtained through calculation possibly has deviation relative to the actual position information, and the preset position is verified according to the CT scanning result, so that the vascular robot can reach the preset position more accurately.
It should be noted that the control method or system of the vascular robot based on autonomous control according to the embodiments of the present invention is not a method for diagnosing or treating a disease, but is merely a computer system-based control method for the vascular robot to operate in a blood vessel. For example, the method of the embodiment of the invention can be used for analyzing the blood flow in the animal blood vessel, the structure in the animal blood vessel and the like in the scientific research process.
The invention also provides a control system of the vascular robot based on the autonomous control, which executes the steps of the control method of the vascular robot based on the autonomous control.
The beneficial technical effects are as follows: compared with the prior art, the invention can realize that: the control information of the vascular robot can accurately control the moving speed and position of the vascular robot by generating the navigation path information of the vascular robot based on the three-dimensional vascular network image; whether the pressure information transmitted back by the vascular robot exceeds a preset alarm threshold value or not is set, so that the vascular robot is not damaged by overlarge pressure when in operation; and the invention is different from the way of controlling the positioning of the robot without a catheter, the invention judges whether the vascular robot reaches the preset virtual position or not through the navigation path information of the robot, when the vascular robot reaches the preset virtual position, the preset position is checked according to the CT scanning result, and when the check is passed, the vascular robot is determined to reach the preset position, thereby ensuring that the robot can reach the required position.
It is understood that various other changes and modifications may be made by those skilled in the art based on the technical idea of the present invention, and all such changes and modifications should fall within the protective scope of the claims of the present invention.