Technical background
In recent years, minimally-invasive surgery robot systems such as da Vinci are applied to clinical gradually, and it combines the traditional medical apparatus with infotech, Robotics, make surgical diagnosis and treatment reach Wicresoftization, microminiaturization, intellectuality.Micro-wound operation robot is compared with traditional operation has significant advantage: at first robot improves doctor's mode of operation, and the standard operation technique improves the operation quality, Minimally Invasive Surgery is developed and popularizes have important impetus; In addition, robot does not have human sense tired out and physiology restriction, is not subjected to environmental stimuli, and it is very little that work range can design, the precision height of executable operations, flexible operation, extend the functipnal capability of doctor's hand, eye, eliminated the intrinsic of staff and tremble, prolonged the surgical occupation life-span.Robot itself is not afraid of and is subjected to x radiation x.These advantages make robot become doctor's best assistant.
Yet micro-wound operation robot also has its hidden danger that need overcome.Compare with traditional operation, in the robotic surgery, the operator can't the Direct observation operative site, doctor's hand eye coordination difficulty, and the scope of activities of operating theater instruments is also unlike traditional operation, operation need rely on sight glass to judge focus in very little space fully, and the operating theater instruments of operating various complexity excises focus and sewing up a wound, and therefore, degree of accuracy is difficult to improve, the human factor of both hands slight jitter and so on also can't be got rid of, and this also has higher requirement for the doctor.Without training, the surgeon is difficult to competent this novel modus operandi.But traditional training and training except using corpse and animal, are not better trained and simulation means.The utilization animal gives training, and on the one hand, the anatomical structure of animal is different with the anatomical structure of human body, also can be subjected to the condemnation of Animal Protection Association on the other hand, and people's corpse is can not be nonexpondable.
If the characteristics of micro-wound operation robot are combined with the virtual operation technology, develop a cover robot Minimally Invasive Surgery analogue system, then can address the above problem.This technology simulates the human organ model from medical image in computing machine, create virtual medical environment and virtual operation robot, and dummy robot's minimal invasive surgical procedures of assisting.The multi-door subjects such as medical science, computer graphics, biomechanics, Mechanics of Machinery, materialogy that needed integrated application.Increasingly extensive along with the continuous development of micro-wound operation robot technology and clinical practice, the following training that needs a large amount of doctors to accept the micro-wound operation robot surgical technic.Therefore, the system of virtual operation based on micro-wound operation robot has become a novelty and urgent research direction.
At present, similar system is very rare, the work of some this respects has been done by Tokyo Ci Hui meeting medical university and Hong Kong Chinese University based on Leonardo da Vinci's operating robot, obtained certain achievement in research, but the system that develops is still very immature, and domestic operation emulation based on operating robot is not extensively carried out as yet, this respect research both domestic and external in a word also is in the starting stage, often has robot motion analog distortion, Soft Tissue Deformation distortion, lacks problems such as force feedback or force feedback distortion.
Summary of the invention
The present invention is directed to the present Research of robot Minimally Invasive Surgery,, design a kind of robot Minimally Invasive Surgery analogue system that can carry out repeatedly based on force feedback at its problem and shortage that exists at present.
Robot Minimally Invasive Surgery analogue system based on force feedback of the present invention is by the force feedback awareness apparatus, the force feedback module, database module, image processing module, physical modeling module and graph rendering module constitute, force feedback module output control signal is given the force feedback awareness apparatus, described force feedback awareness apparatus power output feeds back signal to the force feedback module, force feedback module output collision alarm is given graph rendering module, image processing module reads image data from database module, described image processing module output three-dimensional reconstruction information is given the physical modeling module, described physical modeling module output physical model information is given the force feedback module, and described force feedback module reads kinematic constraint information from database module; Described pattern rendering module also reads kinematic constraint information from database module;
Described database module is used for storing medical image raw data, robot Minimally Invasive Surgery apparatus model data and kinematic constraint information;
Described image processing module is used for the image data of reading of data library module, and converts the image data that reads to three-dimensional data;
Described physical modeling module is used for the three-dimensional data of reading images processing module, and makes up geometric model according to described three-dimensional data;
Described force feedback module, be used for going out the size and Orientation of feedback force according to the calculation of parameter that the geometric model and the force feedback awareness apparatus of physical modeling module construction are exported, and these feedback forces are outputed to the force feedback awareness apparatus after controlling and compensating, and then make the operator experience power by this force feedback awareness apparatus;
Described graph rendering module, the image information after being used for robot motion's information acquisition that the collision information that sends according to the force feedback module and database module sent and playing up, and realize the output of video information.
Described physical model information comprises particle postition, the elastic coefficient and ratio of damping.
Database module described in the present invention can be made up of image database, robot Minimally Invasive Surgery apparatus model bank and kinematic constraint unit, and wherein: image database is used for the storing medical image raw data; Robot Minimally Invasive Surgery apparatus model bank, the partial model and the various operating theater instruments model data that are used to store micro-wound operation robot; The kinematic constraint unit is used for storing each parts that robot Minimally Invasive Surgery apparatus model bank stores and the kinematical constraint connection relation and the characteristics of motion between the various operating theater instruments.
In the model data in the robot Minimally Invasive Surgery apparatus model bank described in the present invention, given different materials, different diffusing has been set for the model of each moving component.
Image processing module described in the present invention can be made up of image pretreatment unit and three-dimensional reconstruction unit, image pretreatment unit wherein, image data in the reading of data library module, and described image data carried out sending to after the image pre-service three-dimensional reconstruction unit; The three-dimensional reconstruction unit, the data that are used to adopt the MC algorithm to obtain after the image pre-service are carried out three-dimensional reconstruction, obtain three-dimensional data.
Force feedback module described in the present invention can be made up of collision detection unit, particle displacement change calculations unit, feedback force computing unit and power control and compensating unit, collision detection unit wherein, be used to judge whether the end of robot bumps with organ, and the positional information that accurate location model bumps under situation about bumping, and the positional information that will collide sends to graph rendering module and particle displacement change calculations unit simultaneously; Particle displacement change calculations unit, be used for when receiving the collision information that collision detection unit sends, calculate the change in displacement information of the particle of position of collision immediately, and then obtain the deformation data of organ model, and the change in displacement information of described particle is sent to the feedback force computing unit; The feedback force computing unit is used for calculating the information that obtains feedback force according to the particle displacement change information, and this feedback force information is sent to power control and compensating unit; Power control and compensating unit are used for obtaining force compensating information according to force feedback information, send power control information and force compensating information and send to the force feedback awareness apparatus.
Above-mentioned collision information comprises the direction and the position of collision.
Graph rendering module described in the present invention can be made up of image rendering unit and video output unit, and image such as wherein said image rendering unit is used to create viewpoint, illumination is set, data read, form renewal, form destruction is played up operation; Described video output unit is used for converting the image information of image rendering unit output to video information output.
Robot Minimally Invasive Surgery analogue system based on force feedback of the present invention based on a kind of micro-wound operation robot mechanism, and with the medical image data of the real human body construction basis as simulated environment, has following remarkable advantage:
1, broken through the training and the teaching pattern of traditional Minimally Invasive Surgery, avoided using the sample of anyone or animal, and can unlimitedly use repeatedly.
2, analogue system is based on a kind of minimally-invasive surgery robot system, and simulating scenes can be realized the switching between the operative scenario in robot motion's scene and the human body, that is can realize traditional Minimally Invasive Surgery emulation and two kinds of mode of operations of robot Minimally Invasive Surgery emulation simultaneously.The kinematics characteristics of operating robot and mechanism form can change effectively simulates real real machine people's various motions flexibly.
3, the function that has accurate force feedback can be felt during operation and the suitable power of true operation, can strengthen the sense of reality of doctor's operation effectively.
4, utilize advanced medical image technology and computer image processing technology,, utilize correlation technique structure internal organs, focus and whole surgery district physiological environments such as three-dimensional reconstruction based on the medical image of real human body.Realized the digitizing, visual of surgical field of view.
5, can utilize certain disease patient's image data to carry out modeling, design a kind of training and tutoring system at certain disease, help surgeon undergo surgery teaching, surgery planning and preview, training by repeatedly and demonstration make the surgeon be familiar with whole operation details at a kind of robot Minimally Invasive Surgery or the common Minimally Invasive Surgery of certain disease.
6, the soft tissue organs Visualization Model has the physical characteristics of tissue, can realize viscoelastic deformation true to nature when operating theater instruments interacts with it.
7, system delay is little, can realize real-time simulation.
Embodiment
Embodiment one, present embodiment is described referring to Fig. 1.The described robot Minimally Invasive Surgery analogue system based on force feedback of present embodiment is by force feedback awareness apparatus 5, force feedback module 4, database module 1, image processing module 2, physical modeling module 3 and graph rendering module 6 constitute, force feedback module 4 output control signals are given force feedback awareness apparatus 5, described force feedback awareness apparatus 5 power outputs feed back signal to force feedback module 4, force feedback module 4 output collision alarms are given graph rendering module 6, image processing module 2 reads image data from database module 1, described image processing module 2 output three-dimensional reconstruction information are given physical modeling module 3, described physical modeling module 3 output physical model information are given force feedback module 4, and described force feedback module 4 reads kinematic constraint information from database module 1; Described pattern rendering module also reads kinematic constraint information, graph rendering module 6 from database module 1;
Described database module 1 is used for storing medical image raw data, robot Minimally Invasive Surgery apparatus model data and kinematic constraint information;
Described image processing module 2 is used for the image data of reading of data library module 1, and converts the image data that reads to three-dimensional data;
Described physical modeling module 3 is used for the three-dimensional data of reading images processing module 2, and makes up geometric model according to described three-dimensional data;
Described force feedback module 4, be used for going out the size and Orientation of feedback force according to the calculation of parameter that the geometric model and the force feedback awareness apparatus 5 of physical modeling module 3 structures are exported, and these feedback forces are outputed to the force feedback awareness apparatus after controlling and compensating, and then make the operator experience power by this force feedback awareness apparatus 5;
Described graph rendering module 6, the image information after being used for robot motion's information acquisition that the collision information that sends according to force feedback module 4 and database module 1 sent and playing up, and realize the output of video information.
Described physical model information comprises particle postition, the elastic coefficient and ratio of damping described in the present embodiment.
Force feedback awareness apparatus 5 described in the present embodiment can adopt the virtual haptic equipment of existing Omega.Choosing model in the present embodiment is the virtual haptic equipment of OMEGA.3.
Embodiment two, present embodiment is described referring to Fig. 1.Present embodiment is the explanation to a kind of embodiment of the database module 1 described in the embodiment one, database module 1 described in the present embodiment is made up of image database 1-1, the Minimally Invasive Surgery apparatus model bank 1-2 of robot and kinematic constraint unit 1-3, wherein:
Image database 1-1 is used for the storing medical image raw data;
The Minimally Invasive Surgery apparatus model bank 1-2 of robot, the partial model and the various operating theater instruments model data that are used to store micro-wound operation robot;
Kinematic constraint unit 1-3 is used for storing each parts that the Minimally Invasive Surgery apparatus model bank 1-2 of robot stores and the kinematical constraint connection relation and the characteristics of motion between the various operating theater instruments.
Medical image raw data described in the present embodiment comprises the image data of different sexes, all ages and classes, various disease.These data are all stored and are read according to the DICOM data standard.
The described medical image raw data of present embodiment can be the view data of gathering from medical supplies such as CT or MRI.
In the partial model and various operating theater instruments model of the micro-wound operation robot of storing among the described Minimally Invasive Surgery apparatus model bank 1-2 of robot, include the relevant kinematics information of Minimally Invasive Surgery apparatus, described relevant kinematics information is meant under certain coordinate definition, according to the robot end position, both can resolve in conjunction with above-mentioned data and to have obtained whole rod members each self-corresponding position and attitude, and just solve robot each rod member when action and how to have upgraded position and this problem of attitude of oneself.These data show as one group of matrix on mathematics, each rod member all has two matrixes, an expression attitude, an expression position.Interrelated between these matrixes, formed a kind of kinematic constraint, make virtual robot in the light of actual conditions to move.
Model data among the Minimally Invasive Surgery apparatus model bank 1-2 of robot described in the present embodiment, all be that these model datas export as the 3DS form and store by the data of actual object being surveyed acquisition, the model data of utilizing 3D modeling software such as 3D Studio MAX foundation to obtain.These model datas all are open, also are variable, and these model datas are to link up the operating robot of forming in the simulated environment according to kinematical constraint by kinematic constraint unit 1-3.
Embodiment three, present embodiment is described referring to Fig. 1.Present embodiment is further specifying Minimally Invasive Surgery apparatus model bank 1-2 of robot described in the embodiment two and kinematic constraint unit 1-3, in the model data among the Minimally Invasive Surgery apparatus model bank 1-2 of robot described in the present embodiment, given different materials for the model of each moving component, different diffusing has been set.Like this, can strengthen the demonstration of robot motion unit in virtual environment.
Kinematic constraint related data among the described kinematic constraint unit 1-3 is according to the DH algorithm position and the attitude of robot to be stipulated.
Embodiment four, present embodiment is described referring to Fig. 1.Present embodiment is the explanation to a kind of embodiment of the image processing module 2 described in the embodiment one, and the image processing module 2 described in the present embodiment is made up of image pretreatment unit 2-1 and three-dimensional reconstruction unit 2-2, wherein:
Image pretreatment unit 2-1, the image data in the reading of data library module 1, and described image data carried out sending to after the image pre-service three-dimensional reconstruction unit 2-2; Described image pre-service comprises the pretreated technological means of primary image such as gray scale enhancing, Threshold Segmentation.
Three-dimensional reconstruction unit 2-2, the data that are used to adopt the MC algorithm to obtain after the image pre-service are carried out three-dimensional reconstruction, obtain three-dimensional data.
Described image processing module 2 can obtain a three-dimensional data, gets ready for next step carries out physical modeling.Accompanying drawing 13-16 is a human body soft tissue model storehouse department pattern, is respectively the organize models in gall-bladder, blood vessel and abdominal cavity, and described model is based on that geometric model that above-mentioned three-dimensional data shines upon out sets up.
Embodiment five, present embodiment is described referring to Fig. 1.Present embodiment is the explanation to a kind of embodiment of the physical modeling module 3 described in the embodiment one, and the physical modeling module 3 described in the present embodiment is made up of subregion grid division unit 3-1 and improved particle spring modeling unit 3-2, wherein:
Subregion grid division unit 3-1 is used for according to focus distribution, internal organs characteristics and care zone three-dimensional data being carried out the subregion grid dividing;
Improved particle spring modeling unit 3-2 is used for carrying out preliminary modeling according to the three-dimensional data after the subregion grid dividing, obtains particle-spring model, and Newton second law is followed in the motion of the single particle in this particle-spring model, for particle i:
In the formula:
m
iThe quality of expression particle i; x
IjRelative displacement between expression particle i and the particle j, g represents acceleration of gravity; N is a positive integer, the quantity of the particle that expression and particle i have an effect.
The described physical modeling of present embodiment has been taken all factors into consideration gravity factor, damping factor etc. when modeling, and the elasticity coefficient of spring model is carried out regionality distribution setting, but also utilizes related function to consider some dynamicss of model.These work are that the physical property that virtual operation fully highlights surgical object when carrying out is got ready.
Embodiment six, present embodiment is described referring to Fig. 1.Present embodiment is the explanation to a kind of embodiment of the force feedback module 4 described in the embodiment one, force feedback module 4 described in the present embodiment is made up of collision detection unit 4-1, particle displacement change calculations unit 4-2, feedback force computing unit 4-3 and power control and compensating unit 4-4, wherein:
Collision detection unit 4-1, be used to judge whether the end of robot bumps with organ, and the positional information that accurate location model bumps under situation about bumping, and the positional information that will collide sends to graph rendering module 6 and particle displacement change calculations unit 4-2 simultaneously;
Particle displacement change calculations unit 4-2, be used for when receiving the collision information that collision detection unit 4-1 sent, calculate the change in displacement information of the particle of position of collision immediately, and then obtain the deformation data of organ model, and the change in displacement information of described particle is sent to feedback force computing unit 4-3;
Feedback force computing unit 4-3 is used for calculating the information that obtains feedback force according to the particle displacement change information, and this feedback force information is sent to power control and compensating unit 4-4;
Power control and compensating unit 4-4 are used for obtaining force compensating information according to force feedback information, send power control information and force compensating information and send to force feedback awareness apparatus 5.
Power control described in the present embodiment and compensating unit 4-4 are used for force feedback is carried out perfect, take all factors into consideration damping, gravity and kinetic factor force signal is compensated.
Collision information described in the present embodiment comprises the direction and the position of collision.
Embodiment seven, present embodiment is described referring to Fig. 1.Present embodiment is the explanation to a kind of embodiment of the graph rendering module 6 described in the embodiment one, and the graph rendering module 6 described in the present embodiment is made up of image rendering unit 6-1 and video output unit 6-2, wherein:
Images such as described image rendering unit 6-1 is used to create viewpoint, illumination is set, data read, form renewal, form destruction are played up operation;
Described video output unit 6-2 is used for converting the image information of image rendering unit 6-1 output to video information output.
The present invention can realize the micro-wound operation robot Analog Simulation System of carrying out repeatedly with the medical image data of the real human body construction basis as simulated environment.
The present invention adopts virtual haptic equipment as force feedback awareness apparatus 5, in the process that realizes analogue system of the present invention, can realize in conjunction with a developing instrument Chai3D of programming language C++, openGL and virtual haptic system, described developing instrument Chai3D is an OO kit based on C++, the abstract function of a lot of higher levels is provided, can need not too much to consider the physical layer interface function in the performance history, thereby can consider the generation of scene, calculating and the control that physical modeling feeds back with joint efforts by emphasis, embodiment is as follows:
Establishment for scene, at first to utilize cWorld, cLight, three classes of cCamera to define three objects, purpose is to create a virtual environment and illumination is set and view information, also to stipulate simultaneously information such as the size of form, position, style, demonstration, refresh cycle, also need simultaneously feedback awareness apparatus 5 is discerned, these work major parts are finished in graph rendering module 6, and each module begins to carry out work according to certain triggering and program circuit under this prerequisite.
To the motion simulation of robot, realize by canned data and force feedback awareness apparatus 5 and graph rendering module 6 among Minimally Invasive Surgery apparatus model bank 1-2 of robot and the kinematic constraint unit 1-3.
Referring to the set up process of Fig. 2-12 for the realistic model of micro-wound operation robot part, be implemented in the motion association of each parts in the virtual environment by programming, comprise big arm; forearm and terminal action; promptly: each robot Minimally Invasive Surgery apparatus model group load shown in Fig. 2-11 is connected together;; after little apparatus assembling of operation usefulness shown in Figure 10; be installed on the base shown in Figure 11, finally form the realistic model of the robot arm that is used for Minimally Invasive Surgery shown in Figure 12 with Fig. 2 and 3 described two passive transverse arms; passive upright arm shown in Figure 4; four master arms shown in Fig. 5-8; slide unit shown in Figure 9.
The realistic model of the robot arm that is used for Minimally Invasive Surgery that above-mentioned foundation obtains is in the motion of virtual environment, be under the constraint of kinematic constraint unit 1-3, to accept controlling of feedback awareness apparatus 5, and the characteristics of kinematic constraint have determined robot end 7-4 manipulater to move around the apocenter O shown in the robotic surgery end effector principle of work shown in the accompanying drawing 19, among Figure 19,7-1 is a sleeve pipe, 7-2 is little apparatus of laparoscope or other operations, 7-3 is the little of operation usefulness, 7-4 is meant the end of little apparatus, 7-5 is meant the soft tissue of human organ model, what the arrow among the figure was represented each parts can move direction, therefore the operator just can make robot end in the virtual environment reach any desired location in the operative space by this feedback awareness apparatus 5, and then implements virtual operation and operate.Effectively motion simulation has highlighted the work characteristics of micro-wound operation robot.
Force feedback module 4 in the analogue system of the present invention, when being used to realize that analog simulation is worked as operative site and robot end and do not bumped, referring to shown in Figure 20, robot in the micro-wound operation robot operation simulating scenes moves by the aforementioned machines people motion simulation characteristics of motion, does not have power to feel during doctor's operational feedback awareness apparatus 5 and experiences.
When robot in the virtual environment contacts with organ, force feedback module 4 is had an effect, terminal and the organ of operating robot has an effect, at first judges whether collision has taken place between virtual operation robot end and the organ at collision detection unit 4-1, and under situation about bumping the position that bumps of location model accurately.Enable particle displacement change calculations unit 4-2 then model is implemented deformation process, the visual context of enabling simultaneously after control of feedback force computing unit 4-3 and power and compensating unit 4-4 will interact shows by graph rendering module 6, accompanying drawing 21 and Figure 22 have shown that the end of little apparatus in the micro-wound operation robot surgical procedure grasps the view of process and distortion, Figure 23 grasps simulating scenes figure afterwards, when grasping, to the feedback awareness apparatus 5 stable force feedback of output in real time, power is felt refresh rate more than 1000Hz, and then feels impression effectively when making doctor's operational feedback awareness apparatus 5.