CN102385761B - Logical reasoning-based rapid collision detection method in virtual operation simulation - Google Patents

Abstract

The invention relates to a logical reasoning-based rapid collision detection method in virtual operation simulation, which comprises the following steps: tracking all joint motions of one hand of an operator by utilizing a data glove, and implementing motion control on a virtual hand; according to the positional relationship between the virtual hand and a virtual object when the virtual hand grabs the virtual object, computing the included angle between the motion vector of the tail end of each finger and the normal vector of the position at which the tail end of the finger is contacted with the surface of the object last time; judging the motion directions of all fingers according to the included angles; performing logic reasoning according to the motion directions of the fingers; reasoning whether the fingers are contacted with the object or not on the basis whether fingers are contacted with the object or not in a previous frame; if the fingers are contacted with the object, not performing basal collision detection computation in the frame; and if the fingers are not contacted with the object, performing the basal collision detection computation in the frame, thereby, the invention provides the logical reasoning-based rapid collision detection method in the virtual operation simulation, which is capable of enabling the operation simulation that the virtual hand grabs the virtual object to be accurate and rapid.

Description

The Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation

Technical field

The present invention relates to a kind of computer simulation technique field, particularly a kind of in pseudo operation simulation process under virtual environment for the grasped Track character, the situation that contacts based on static collision checking method and former frame adopts the method for reasoning from logic how to judge fast virtual hand various piece and the collision checking method that is grasped object.

Background technology

In pseudo operation emulation, need to judge according to the collision detection result between virtual hand and dummy object whether virtual hand catches object, in this grasping reciprocal process, need the real time collision detection of simultaneously carrying out between five fingers and dummy object to calculate, and be the process of a continuous contact, the travelling speed of colliding detection-phase has been proposed to higher requirement.

Collision Detection Algorithm is a lot of at present, comprising: the collision detection algorithm based on bounding box, the collision detection algorithm that distance-based calculates, the collision detection algorithm based on Wei Nuotu, the collision detection algorithm of processing based on image; Some algorithm software bag: Opcode, RAPID, SOLID, PQP, QuickCD, SWIFT etc. are also arranged.These are all the research for static collision detection algorithm between two objects, and its basic thought is all to discharge as early as possible those discontiguous object or parts, searches as early as possible interested zone, i.e. part or the tri patch of possibility contactant body.The best situation of algorithm is that object does not contact, and collision detection algorithm can be got rid of object very soon, and the program operation is the fastest; The worst situation is that two each tri patchs of object are contacted by the other side's object tri patch, the collision detection algorithm of the bounding volume hierarchy (BVH) of take tree is this situation as example illustrates, in the collision detection stage, program need to travel through each node in the bounding box tree, detect in twos, leaf node detected, speed is obviously very slow always.For two objects of continuous contact, program all needs from first to last according to this step, to carry out collision detection calculating in each frame circulation, and travelling speed is slow.And the computer model due to both after an object enters into other interior of articles is all that surface model judges that by the method both do not contact, and this does not meet two object contact situations of real world.

The characteristics that therefore need to grasp dummy object according to virtual hand judge fast the virtual hand various piece with the collision checking method of being grabbed object and can judge after an object enters into another interior of articles to judge the being situation of colliding.

Summary of the invention

For the defect of above-mentioned prior art, the purpose of this invention is to provide a kind of Fast Collision Detection Algorithm that can make virtual hand grasp logic-based reasoning in the pseudo operation emulation quickly and accurately of dummy object operational simulation.

For achieving the above object, the present invention adopts following technical scheme:

The Fast Collision Detection Algorithm of logic-based reasoning in a kind of pseudo operation emulation comprises the following steps:

Utilize data glove to operator's hand each joint motions followed the tracks of, implement the motion control to virtual hand;

Position relationship while 1) according to virtual hand, grasping dummy object between virtual hand and dummy object, calculate the angle between finger tips motion vector and the last finger tips and body surface contact position method vector, judge the direction of motion of each finger according to described angle; Position relationship when wherein, described virtual hand grasps dummy object between virtual hand and dummy object comprises:

Finger, to this lateral movement of object, never contacts object to the contact object;

After the contact object, if do not have force feedback equipment to stop operator's hand to continue motion, virtual finger will move to interior of articles;

Contact object defensive position is pointed to and is deviated from the motion of object direction, unclamps object and separates with object;

Finger motion deviates from the motion of object direction to interior of articles is backward, but finger still continues to contact at interior of articles and with object;

The computing formula of the angle between described calculating finger tips motion vector and the last finger tips and body surface contact position method vector is:

$\mathrm{\α}=\arccos \left(\frac{\stackrel{\‾}{p_1{p}_2}\·\stackrel{\‾}{N}}{\left|\stackrel{\‾}{p_1{p}_2}\right|\×\left|\stackrel{\‾}{N}\right|}\right);0\≤\mathrm{\α}\≤\mathrm{\π};$

Wherein

for the finger tips motion vector,

for the normal vector at contact point place, α is angle;

The step that judges the direction of motion of each finger according to described angle is to be the direction of motion that acute angle or obtuse angle judge each finger according to described angle;

2) carry out reasoning from logic according to the finger motion direction, on the basis whether contacted at previous frame reasoning finger whether with object contact, finger and object contact, this frame does not carry out basic collision detection and calculates, finger does not contact with object, and this frame carries out basic collision detection and calculates; Wherein, describedly according to the finger motion direction, carry out reasoning from logic, whether contact at previous frame and infer finger on the basis of situation and whether comprise with the step of object contact:

If previous frame contacts, if αWei obtuse angle, angle shows that finger is to this side direction motion of object, finger continues and object contact, and this frame does not carry out basic collision detection and calculates;

If angle α is acute angle, show that finger is to deviating from the motion of object direction, this frame need carry out basic collision detection and calculate, and records the collision detection result and the finger contact sign is set; If previous frame is contact not, this frame need to carry out collision detection calculating, records the collision detection result and the finger contact sign is set.

The Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention, step 2 wherein) carry out reasoning from logic according to the finger motion direction, on the basis whether contacted at previous frame reasoning finger whether with the detection method of object contact, comprise the steps:

(1) finger contact is masked as " mistake ", obtains and record last finger tips position;

(2), obtain and record current finger tips position;

(3), judge whether the finger contact sign is " correctly ", if correct, carry out next step; Otherwise execution step (8);

(4), according to finger tips motion vector and calculating angle α, judgement finger motion direction, wherein the finger tips motion vector is current finger tips position-finger tips last time position;

(5), whether the judgement finger shifts to object, if so, carries out next step; Otherwise execution step (8);

(6), finger contact is set and is masked as " correctly ";

(7), current finger tips position is covered to finger tips last time position, and execution step (2);

(8), finger and object collision detection computations;

(9), record the collision detection result, the finger contact sign is set, and execution step (7).

The Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention, the detection method of position relationship when wherein the step 1) virtual hand grasps dummy object between virtual hand and dummy object, comprise the steps:

(1), judge in 5 fingers;

(2), obtain the current terminal position of finger;

(3), judge whether the finger contact sign is " correctly ", if correct, carry out next step; Otherwise execution step (8);

(4), according to finger tips motion vector and calculating angle α, judgement finger motion direction, wherein the finger tips motion vector is current finger tips position-finger tips last time position;

(5), whether the judgement finger shifts to object, if so, carries out next step; Otherwise execution step (8);

(6), finger continues and object contact, does not carry out basic collision detection;

(7), current finger tips position is covered to finger tips last time position, and execution step (1);

(8), point and the object collision detection computations;

(9), the finger contact sign is set;

(10), judgement finger whether with object contact, if so, execution step (11); If not, execution step (12);

(11), calculate and record the contact point coordinate, normal vector; Finger contact is set and is masked as " correctly ", and execution step (7);

(12), the finger contact sign is not set, and execution step (7).

The Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention, wherein said data glove adopts CyberGlove.

The Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention, wherein said data glove arranges 22 sensors.

The Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention, wherein said dummy object is with surface model simulation/Solid simulation model.

The present invention is directed to the people and wear the method that the characteristics in data glove control virtual hand grasping dummy object simulation process adopt the method for reasoning from logic to carry out Fast Collision Detection calculating.The present invention utilize data glove to operator's hand each joint motions followed the tracks of, the motion control of enforcement to virtual hand, the movement characteristic that grasps dummy object according to virtual hand calculates angle α, according to angle α, be the direction of motion that acute angle or obtuse angle judge each finger, carry out reasoning from logic according to direction of motion, at previous frame, whether contact on the basis of situation infer finger whether with object contact, can solve virtual finger and enter into testing result and the inconsistent situation of real general knowledge that adopts static collision checking method to draw after interior of articles, thereby realize the purpose with the surface model Solid simulation model.The actual collision that the method reduces between finger and object on the whole detects number of times, improves collision detection speed.

The accompanying drawing explanation

Fig. 1 a is that the one hand of the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention refers to grasp object finger and rigidly connects and touch the object schematic diagram;

Fig. 1 b is that the one hand of the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention refers to grasp the object finger to object one lateral movement schematic diagram;

Fig. 1 c is that the one hand of the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention refers to grasp object finger and deviates from object of which movement, unclamps rear separation schematic diagram;

Fig. 1 d is that the one hand of the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention refers to grasp object finger and deviates from object of which movement, continues the contact schematic diagram;

Fig. 2 is the collision detection algorithm process flow diagram based on the judgement of finger motion direction of the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention;

Fig. 3 is the collision detection realization flow figure that the virtual hand of the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention grasps dummy object.

Embodiment

Embodiment below in conjunction with accompanying drawing to the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation of the present invention is elaborated.

The people wears the motion that data glove is controlled the virtual hand various piece in virtual environment, judge the direction of relative movement of two objects by the value of a quantification in the process of virtual finger grasping object, if two object move toward one another, object is in the situation that the previous frame contact so, this frame also continues contact, at this frame, no longer carries out actual collision detection computations (best-case); If two objects are to move dorsad, two objects may continue contact and also may not contact so, need to carry out the collision detection (utilize static collision detection algorithm storehouse as Opcode etc.) of essence and calculate to determine.This algorithm can be with the collision detection between the collision detection Solid simulation model between surface model simultaneously.

In pseudo operation emulation of the present invention, the Fast Collision Detection Algorithm of logic-based reasoning comprises following operation steps:

The operator controls the motion of virtual hand: the operator wears data glove, and data glove is connected with computing machine, operator's hand exercise is controlled by data glove by computing machine, and then is controlled the motion of virtual hand in virtual environment.

The operator wears the motion that the data glove (CyberGlove of Immersion company) with 22 sensors is controlled virtual hand, data glove is connected with computing machine, gather the data of each sensor by data glove, data are processed, and then each joint motions of people are followed the tracks of.

The judgement of virtual finger direction of motion and calculating:

The process of analyzing virtual grasped object, can divide four kinds of situations the reciprocal process of virtual hand and object:

Referring to Fig. 1 a, finger, to this lateral movement of object, never contacts object to the contact object;

Referring to Fig. 1 b, after the contact object, if do not have force feedback equipment to stop operator's hand to continue motion, virtual finger will move to interior of articles;

Referring to Fig. 1 c, contact object defensive position is pointed to and is deviated from the motion of object direction, unclamps object and separates with object;

Referring to Fig. 1 d, finger motion deviates from the motion of object direction to interior of articles is backward, but finger still continues to contact at interior of articles and with object.

By angle α, be that acute angle or obtuse angle judge the finger motion direction, angle α is defined as the angle between finger tips CD motion vector and the last finger tips CD and body surface contact position method vector.

Referring to Fig. 1 a, mean finger and object contact in the grasping process, but do not enter into interior of articles, contact point is P0, contact point place normal vector is

Referring to Fig. 1 b, mean to move on (grasping object) follow-up continuing to this side direction of object of finger CD contact object, finger CD moves to interior of articles P1 place, finger tips motion vector the normal vector at contact point place while contacting with the last time

between angle α be obtuse angle;

Referring to Fig. 1 c, mean to change direction after finger CD contact object, move to the P1 place, the finger tips motion vector to deviating from the object direction

the normal vector at contact point place while contacting with the last time

between angle α be acute angle;

Referring to Fig. 1 d, mean to change direction after finger CD moves to interior of articles P1, move to the P2 place, the finger tips motion vector to deviating from the object direction

the normal vector at contact point place while contacting with the last time

between angle α be acute angle.

For example, point relative object two direction of motion are arranged: to this lateral movement of object, deviate from object of which movement; By angle α, be that acute angle or obtuse angle judge this two direction of motion.Angle α is defined as: the angle between finger tips CD motion vector and the last finger tips CD and body surface contact position method vector.

The calculating of angle α is by vector

with

vector dot (formula (1)) is calculated, as angle α calculates as shown in Equation (2).

$\stackrel{\&OverBar;}{p_1{p}_2}\&CenterDot;\stackrel{\&OverBar;}{N}\left|\stackrel{\&OverBar;}{p_1{p}_2}\right|\&times;\left|\stackrel{\&OverBar;}{N}\right|\&times;\cos \mathrm{\&alpha;};0\&le;\mathrm{\&alpha;}<\mathrm{\&pi;}---\left(1\right)$

$\mathrm{\&alpha;}=\arccos \left(\frac{\stackrel{\&OverBar;}{p_1{p}_2}\&CenterDot;\stackrel{\&OverBar;}{N}}{\left|\stackrel{\&OverBar;}{p_1{p}_2}\right|\&times;\left|\stackrel{\&OverBar;}{N}\right|}\right);0\&le;\mathrm{\&alpha;}\&le;\mathrm{\&pi;};---\left(2\right)$

When angle α is 0 °, vectorial

for null vector, mean that finger is not mobile with respect to former frame at this frame, finger keeps and object contact (former frame contacts).When angle α is 90 °, vector with vertically; Finger CD in this side direction of object motion (grasping object) process with all may have vertical situation to deviating from object direction motion (unclamping object) process; But, after finger and object contact, do not allow that finger has large like this motion amplitude, in actual computation, this value not there will be; In operating process, if this occurs, it is processed as the situation of unclamping object.Work as angle with the time, according to angle α, be that acute angle or obtuse angle are judged.

Logic reasoning: according to finger motion direction and previous frame contact situation judgement finger whether with the object contact method.

According to angle α, be the direction of motion of acute angle or obtuse angle judgement finger, then in conjunction with the collision situation of previous frame carry out reasoning from logic draw finger whether with object contact, method is: if previous frame contacts, if αWei obtuse angle, angle, show that finger is to this side direction motion of object, finger continues and object contact, and this frame does not carry out basic collision detection and calculates; If angle α is acute angle, show that finger is to deviating from the motion of object direction, this frame need carry out basic collision detection and calculate, and records the collision detection result and the finger contact sign is set; If previous frame is contact not, this frame need to carry out collision detection calculating, records the collision detection result and the finger contact sign is set.

Referring to Fig. 2, the collision checking method based on the judgement of finger motion direction comprises the steps:

Step 201, finger contact is masked as " mistake ", obtains and record last finger tips position;

Step 202, obtain and record current finger tips position;

Step 203, judge whether the finger contact sign is " correctly ", if correct, carries out next step; Otherwise perform step 208;

Step 204, according to finger tips motion vector and calculating angle α, judgement finger motion direction, wherein the finger tips motion vector is current finger tips position-finger tips last time position;

Step 205, whether the judgement finger shifts to object, if so, carries out next step; Otherwise perform step 208;

Step 206, arrange finger contact and be masked as " correctly ";

Step 207, cover finger tips last time position by current finger tips position, and perform step 202;

Step 208, finger and object collision detection computations;

Step 209, record the collision detection result, and the finger contact sign is set, and perform step 207.

Virtual hand grasps the collision detection application of object process:

The situation that the situation of single finger being carried out to reasoning from logic is applied to 5 fingers in Simulation of grasp can show that virtual hand grasps the collision detection application in the dummy object process.

Referring to Fig. 3, virtual hand grasps the collision detection implementation method of dummy object, comprises the steps:

Step 301, judge a finger in 5; Judge for the first time a finger, complete after following steps the judgement of carrying out another finger;

Step 302, obtain the current terminal position of finger;

Step 303, judge whether the finger contact sign is " correctly ", if correct, carries out next step; Otherwise perform step 208;

Step 304, according to finger tips motion vector and calculating angle α, judgement finger motion direction, wherein the finger tips motion vector is current finger tips position-finger tips last time position;

Step 305, whether the judgement finger shifts to object, if so, carries out next step; Otherwise perform step 308;

Step 306, finger continues and object contact, does not carry out basic collision detection;

Step 307, cover finger tips last time position by current finger tips position, and perform step 301;

Step 308, point with object Opcode collision detection and calculate;

Step 309, arrange the finger contact sign;

Step 310, judgement finger whether with object contact, if so, perform step 311; If not, perform step 312;

Step 311, calculate and record the contact point coordinate, normal vector; Finger contact is set and is masked as " correctly ", and perform step 307;

Step 312, do not arrange the finger contact sign, and perform step 307.

In pseudo operation emulation of the present invention the Fast Collision Detection Algorithm of logic-based reasoning in dummy object collision detection simulation process with the application of surface model simulation/Solid simulation model.It is embodied in logic reasoning.

Utilize method of the present invention can correctly judge that a dummy object enters into the situation of the situation downcrossings of another one dummy object, because utilizing the tri patch whether contact is arranged between two polyhedral models, static collision checking method judges whether two dummy objects contact, when a dummy object enters into, in the situation of another one dummy object, both do not have the tri patch of contact, at this moment the conclusion that adopts static collision checking method to draw is both no contacts, but in actual life, object is all solid model, this testing result and reality do not meet.The method that collision detection algorithm based on static utilizes the relation between frame to carry out reasoning from logic can well address this problem, and in virtual collision detection in grasping simulation process, calculates the solid model in utilizing computing machine surface model simulation/emulation real world.

The present invention is directed to the people and wear the method that the characteristics in data glove control virtual hand grasping dummy object simulation process adopt the method for reasoning from logic to carry out Fast Collision Detection calculating.The present invention utilize data glove to operator's hand each joint motions followed the tracks of, the motion control of enforcement to virtual hand, the movement characteristic that grasps dummy object according to virtual hand calculates angle α, according to angle α, be the direction of motion that acute angle or obtuse angle judge each finger, carry out reasoning from logic according to direction of motion, at previous frame, whether contact on the basis of situation infer finger whether with object contact, can solve virtual finger and enter into testing result and the inconsistent situation of real general knowledge that adopts static collision checking method to draw after interior of articles, thereby realize the purpose with the surface model Solid simulation model.The actual collision that the method reduces between finger and object on the whole detects number of times, improves collision detection speed.

Above embodiment is described the preferred embodiment of the present invention; not scope of the present invention is limited; design under the prerequisite of spirit not breaking away from the present invention; various distortion and improvement that the common engineering technical personnel in this area make technical scheme of the present invention, all should fall in the definite protection domain of claims of the present invention.

Claims (6)

1. the Fast Collision Detection Algorithm of logic-based reasoning in a pseudo operation emulation, is characterized in that, comprises the following steps:

Utilize data glove to operator's hand each joint motions followed the tracks of, implement the motion control to virtual hand;

Position relationship while 1) according to virtual hand, grasping dummy object between virtual hand and dummy object, calculate the angle between the normal vector at finger tips motion vector and the last finger tips and body surface contact point place, judge the direction of motion of each finger according to described angle; Position relationship when wherein said virtual hand grasps dummy object between virtual hand and dummy object comprises:

Finger, to this lateral movement of object, never contacts object to the contact object;

After the contact object, if do not have force feedback equipment to stop operator's hand to continue motion, virtual finger will move to interior of articles;

Contact object defensive position is pointed to and is deviated from the motion of object direction, unclamps object and separates with object;

Finger motion deviates from the motion of object direction to interior of articles is backward, but finger still continues to contact at interior of articles and with object;

The computing formula of the angle between described calculating finger tips motion vector and the last finger tips and body surface contact position method vector is:

$\mathrm{\&alpha;}=\arccos \left(\frac{\stackrel{\&OverBar;}{p_1{p}_2}\&CenterDot;\stackrel{\&OverBar;}{N}}{\left|\stackrel{\&OverBar;}{p_1{p}_2}\right|\&times;\left|\stackrel{\&OverBar;}{N}\right|}\right);0\&le;\mathrm{\&alpha;}<\mathrm{\&pi;};$

Wherein

for the finger tips motion vector,

for the normal vector at contact point place, α is angle;

The step that judges the direction of motion of each finger according to described angle is to be the direction of motion that acute angle or obtuse angle judge each finger according to described angle;

2) carry out reasoning from logic according to the finger motion direction, on the basis whether contacted at previous frame reasoning finger whether with object contact, comprising:

If previous frame contacts, if αWei obtuse angle, angle shows that finger is to this side direction motion of object, finger continues and object contact, and this frame does not carry out basic collision detection and calculates;

If angle α is acute angle, show that finger is to deviating from the motion of object direction, this frame need carry out basic collision detection and calculate, and records the collision detection result and the finger contact sign is set; If previous frame is contact not, this frame need to carry out collision detection calculating, records the collision detection result and the finger contact sign is set.

2. the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation according to claim 1, it is characterized in that, step 2 wherein) carry out reasoning from logic according to the finger motion direction, on the basis whether contacted at previous frame reasoning finger whether with the detection method of object contact, comprise the steps:

(1) finger contact is masked as " mistake ", obtains and record last finger tips position;

(2) obtain and record current finger tips position;

(3) judge whether the finger contact sign is " correctly ", if correct, carry out next step; Otherwise execution step (8);

(4) according to finger tips motion vector and calculating angle α, judgement finger motion direction, wherein the finger tips motion vector is current finger tips position-finger tips last time position;

(5) whether the judgement finger shifts to object, if so, carries out next step; Otherwise execution step (8);

(6) finger contact is set and is masked as " correctly ";

(7) current finger tips position is covered to finger tips last time position, and execution step (2);

(8) finger and object collision detection computations;

(9) record the collision detection result, the finger contact sign is set, and execution step (7).

3. the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation according to claim 2, it is characterized in that, the detection method of position relationship when wherein the step 1) virtual hand grasps dummy object between virtual hand and dummy object, comprise the steps:

(1) judge in 5 fingers;

(2) obtain the current terminal position of finger;

(3) judge whether the finger contact sign is " correctly ", if correct, carry out next step; Otherwise execution step (8);

(4) according to finger tips motion vector and calculating angle α, judgement finger motion direction, wherein the finger tips motion vector is current finger tips position-finger tips last time position;

(5) whether the judgement finger shifts to object, if so, carries out next step; Otherwise execution step (8);

(6) finger continues and object contact, does not carry out basic collision detection;

(7) current finger tips position is covered to finger tips last time position, and execution step (1);

(8) point and the object collision detection computations;

(9) the finger contact sign is set;

(10) judgement finger whether with object contact, if so, execution step (11); If not, execution step (12);

(11) calculate and record contact point coordinate, normal vector; Finger contact is set and is masked as " correctly ", and execution step (7);

(12) the finger contact sign is not set, and execution step (7).

4. the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation according to claim 3, is characterized in that, described data glove adopts CyberGlove.

5. the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation according to claim 4, is characterized in that, described data glove arranges 22 sensors.

6. the Fast Collision Detection Algorithm of logic-based reasoning in pseudo operation emulation according to claim 5, is characterized in that, described dummy object is with surface model simulation solid model.

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