CN102566506B

CN102566506B - Online coordination control and Petri net verification method combined with water cutting process

Info

Publication number: CN102566506B
Application number: CN201110435791.7A
Authority: CN
Inventors: 李俊; 戴先中; 孙启瑞; 孙维; 蒋镇汉
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2011-12-23
Filing date: 2011-12-23
Publication date: 2014-02-26
Anticipated expiration: 2031-12-23
Also published as: CN102566506A

Abstract

An online coordination control and Petri net verification method combined with the water cutting process is used for guiding and coordinating a plurality of water jet cutting cross beams and water cutters to avoid collision and finishing cutting tasks stably and parallelly. The method specifically comprises inputting and decomposing computer aided design (CAD) files of a large workpiece to be cut into CAD sub-files of parts to be cut of cross beam systems; further guiding the CAD sub-files into computer aided manufacturing (CAM) software to generate executable numerical control (NC) code files; designing an online coordination control strategy of the multi-cross-beam cutting process; reading cutting information of each cross beam through each NC code file to generate a Petri net model of the multi-cutting process and verifying the correctness of the coordination strategy by the aid of a simulation way of token playing; and respectively installing NC codes and a program of the verified coordination control strategy to a computer digital controller and a coordination control device and executing the multi-cross-beam water cutting process under the online coordination.

Description

The on-line coordination of combination water cutting process is controlled and Petri net verification method

Technical field

The present invention relates to numerical control water jet cutting processing field, specifically, relate to coordination control and the verification method of many cross beam types water jet cutting machine bed of large-scale workpiece.

Background technology

Water jet cutting (being called for short water cutting) is a kind of some cutting technique of cold conditions, because of fast without thermal deformation and extra-stress distortion, cutting material non-selectivity, cutting speed, and the feature such as pollution-free, obviously be better than other cutting techniques, as inserted tool cutting, cut, spark cutting, plasma cutting etc.Nowadays water cutting technique has been widely used in the industries such as building, decoration, machinery, Aero-Space, propagation, automobile, chemical industry, food, and cutting is 500 polytype materials nearly, as steel, titanium, alloy, compound substance, marble, leather etc.

The medium-and-large-sized workpiece of industry (4-12m and even longer) the water cutting demand rapid growths such as Aero-Space, equipment manufacture, petrochemical industry, food processing in recent years, two kinds large-scale water-jet machine schemes, i.e. single-beam water diced system and many cross beam types water diced system have arisen at the historic moment.Water cutter head and long guide rail and worktable that single-beam water diced system has single crossbeam and is installed on it, but cutting efficiency is lower.Many cross beam types water diced system is spliced and combined and is formed by a plurality of water cutting crossbeams, guide rail, cutting bed, and each crossbeam can cut concurrently.The cutting efficiency of many transverse beam system is significantly higher, possesses again retractility and extensibility, has become the preferred option of large-scale water cutting.Yet many cross beam types water diced system is for guarantee being connected part without cutting dead band, the machining area that must accomplish adjacent crossbeam between two exists certain overlapping.Without any measure in the situation that, once adjacent two transverse beam system have common factor in the period of overlay region, interfere as far as possible and collide, cause the damage of system.Therefore for many transverse beam system, the problem of overriding concern is the coordination of how coordinating between the cutting process of a plurality of parallel and mutual existence constraints, avoids interfering.To this, there are at present off-line and online two kinds of coordination strategies.Prior art mostly is the coordination approach of off-line, general idea is to change the location conflicts problem of many cross beam waters cutting off machine into temporal interference problem, preset each transverse beam system in adjacent cutting process and be positioned at the sequential of interference region, and this coordination strategy is cured to NC code.The method must be carried out synchronous startup, time-out, continuation, rollback, stop each transverse beam system.

On-line coordination strategy, according to the positional information of the adjacent beams detecting online, dynamically determines advancing and halted state and the sequencing that enters interference region of crossbeam.Online control method for coordinating will directly be controlled the CNC controller of each crossbeam, and with the NC code of each transverse beam system be separate, needn't start each transverse beam system simultaneously, time-out, continuation, rollback, stop, each transverse beam system can be accomplished complete independence.Yet the correctness of on-line coordination control strategy has directly determined the reliability of lathe, incorrect or incomplete coordination control strategy very likely causes the collision of adjacent beams, thereby before coordination control strategy puts into practice, must verify it, only be verified as correct coordination control strategy and just can use.At present common verification method is the animation simulation based on virtual prototype, but this check system need to design the lathe of the virtual many transverse beam system of emulation, and the design cycle is long, and emulation is with high costs, is badly in need of simpler and easy and effectively verifies new tool.

Summary of the invention

The object of the present invention is to provide a kind of on-line coordination of combination water cutting process to control and Petri net verification method, described combination water cutting process is to realize with many cross beam types water-jet cutting system, described many cross beam types water-jet cutting system comprise n transverse beam system and n transverse beam system along guide rail direction be arranged in order and be designated as the 1st transverse beam system, the 2nd transverse beam system ..., i transverse beam system ..., n transverse beam system, n is the transverse beam system sum in many cross beam types water-jet cutting system, n ∈ ⁺and n>=2, ⁺for the set of positive integer, i ∈ [1, n], each transverse beam system contains crossbeam and a computer numerical control (CNC) CNC system that is provided with water cutter head, it is characterized in that, and the method comprises the following steps:

A. the machining area of many cross beam types water diced system is divided:

Respectively by the 1st transverse beam system, the 2nd transverse beam system, i transverse beam system, the maximum region that each crossbeam motion in n transverse beam system covers, as the 1st accessoble region, the 2nd accessoble region, i accessoble region, n1 accessoble region, n1=n, using the lap of adjacent j accessoble region and j+1 accessoble region as j overlay region, j ∈ [1, n-1], j overlay region is along two boundary lines of guide rail direction, be called left double line and the right double line of j overlay region, respectively by the 1st overlay region, the 2nd overlay region, the both sides of n2-1 overlay region respectively increase the width of a crossbeam along guide rail, form the 1st interference region, the 2nd interference region, n2-1 interference region, n2=n, by the 1st interference region, the 2nd interference region, n2-1 interference region is along two boundary lines of guide rail direction, be called the 1st left interference line in interference region and right interference line, the 2nd left interference line in interference region and right interference line, the left interference line in n2-1 interference region and right interference line,

B. to given large-scale workpiece cutting task, according to following on-line coordination control method, carry out the cutting of n transverse beam system:

B1. with the form of computer aided design cad file, input given large-scale workpiece cutting task, according to following situation, carry out decomposition and the distribution of cutting profile, form the CAD son file of the cutting part of each transverse beam system:

If B11. profile to be cut is positioned at j overlay region completely, j ∈ [1, n-1], distributes to j transverse beam system or j+1 transverse beam system by profile to be cut;

If profile to be cut is positioned at the region outside the j overlay region of j accessoble region, profile to be cut is distributed to j transverse beam system;

If profile to be cut is positioned at j accessoble region and profile to be cut starts from j overlay region, terminates in outside j overlay region, profile to be cut is distributed to j transverse beam system;

B12. for continuous leap j overlay region, j+1 overlay region ..., j+k-1 overlay region profile to be cut, j, k ∈ [1, n-1] and i+k ∈ [2, n], k ∈ ⁺the overlay region number that representative is crossed over, the center line of each overlapping interference region that the profile to be cut of take is crossed over is boundary, by profile to be cut along guide rail direction be divided into j section, j+1 section ..., j+k-1 section, j+k section, each contour segment to be cut after cutting apart distribute to respectively j transverse beam system, j+1 transverse beam system ..., j+k-1 transverse beam system, j+k transverse beam system;

B2. each above-mentioned CAD son file further imports the auxiliary CAM of manufacture of water cutting calculations machine software, generates executable numerical control (NC) code file:

CAD son file imports the auxiliary CAM of manufacture of water cutting calculations machine software, start-up point, the terminating point of water cutter head, the point of penetration of each profile of the water cutter head of each transverse beam system is set and cuts out the sequencing of point, each contour machining, and the parameter consuming time of setup time, cutting speed, fast forward speed, water and abrasive material valve Push And Release is cut in input, post processor through CAM software is processed, and generates the numerical control NC code file of each transverse beam system;

B3. by the numerical control NC code load of file of each transverse beam system generating in corresponding CNC controller, by cooperative control device, carried out the coordination control strategy of many transverse beam system:

1. start each CNC controller and carry out numerical control NC code, cooperative control device starts to read via each CNC controller circulation Position And Velocity and the direction of each transverse beam system simultaneously, if: in many transverse beam system, any a pair of adjacent beams system is that a transverse beam system in i transverse beam system and i+1 transverse beam system is X, another transverse beam system is Y, 1≤i < n, for transverse beam system X, Y arrange priority;

If 2. X transverse beam system and Y transverse beam system are all worked outside interference region, carry out predetermined NC code;

Once 3. X transverse beam system is advanced to i interference region, and when the distance of the nearest interference line of X transverse beam system and i interference region is less than critical distance, according to following disposal methods, to avoid the collision of any two adjacent transverse beam system to occur, described critical distance is coordinate to control a transverse beam system allowing to the minor increment of closing on a nearest interference line of interference region, be designated as D=V τ, wherein V is that fast forward speed, τ are the cycle period that cooperative control device reads transverse beam system positional information, and described disposal route is:

Situation one: if Y transverse beam system is outside i interference region, and estimate that Y transverse beam system enters i interference region after completing the cutting task of i interference region in X transverse beam system or completing the F.F. in i interference region, X keeps current motion, enters i interference region, and Y will keep current motion; If Y transverse beam system is outside i interference region, and estimate that Y transverse beam system enters i interference region by carrying out in X transverse beam system in the cutting task of i interference region or the process of execution F.F. in i interference region, X keeps current motion, enter i interference region, Y transverse beam system is suspended, until X transverse beam system exits behind i interference region completely, recover the motion before suspending, enter i interference region;

Situation two: if Y transverse beam system is outside i interference region, but estimate that Y transverse beam system will enter i interference region with X transverse beam system simultaneously, now according to the size order of the priority of initial setting up, allow the transverse beam system of high priority keep the current i interference region that is moved into, the transverse beam system of low priority is suspended, until the transverse beam system having entered exits behind i interference region completely, recovers the motion before suspending, enter i interference region

C. above-mentioned cooperative control device is that the industrial control computer of carrying out many transverse beam system coordination control strategy, programmable logic controller (PLC) PLC, embedded controller or other have the electronic installation of calculating, storage unit and known communication interface, cooperative control device.

Preferably, described many cross beam waters diced system on-line coordination is controlled and Petri net verification method, also comprised after step B3 in the Petri net modeling and simulation verification step of coordination control strategy:

D. read preparatory function G instruction code and subsidiary function M instruction code in above-mentioned each numerical control NC code file, obtain transverse beam system motion and cutting profile information, the motion of described transverse beam system and cutting profile information comprise water cutter head start-up point, water cutter head terminating point, each profile and each profile point of penetration with cut out a little, determine the precedence of profile cut and the F.F. route between profile and profile, finally form the feed path of each transverse beam system;

E. every profile and every the fast inbound path of crossing over interference line in the profile of each transverse beam system will be distributed to, take interference line as boundary's segmentation mark, all profiles are marked as to contour segment and interference region outline section two classes in interference region according to the sequencing of processing, by distributing to contour segment and interference region outline section in the interference region of i transverse beam system, are designated as respectively

1 \leq α \leq m_{1}^{i},

1 \leq β \leq m_{2}^{i},

be respectively the sum of contour segment and interference region outline section in the interference region of distributing to i transverse beam system, again all fast inbound path of each transverse beam system is marked as to F.F. route segment and interference region extra income inbound path section two classes in interference region according to the sequencing of processing, F.F. route segment in the interference region of i transverse beam system and interference region extra income inbound path section are designated as respectively

1 \leq χ \leq l_{1}^{i},

1 \leq γ \leq l_{2}^{i},

be respectively the sum of F.F. route segment and interference region extra income inbound path section in the interference region of i transverse beam system;

F. according to the parameter consuming time of cutting setup time, cutting speed, fast forward speed, water and abrasive material valve Push And Release, calculate the cutter head start-up course TO consuming time of i transverse beam system ⁱwith cutter head termination procedure TE consuming time ⁱ, in feed path, in interference region, the execution time of contour segment and interference region outline section is designated as respectively

respectively with

corresponding one by one, and in the interference region of i transverse beam system the execution time of F.F. route segment and interference region extra income inbound path section be designated as respectively

respectively with

corresponding one by one;

G. set up the Petri pessimistic concurrency control of the many cross beam waters cutting process under above-mentioned coordination control strategy effect:

1. the cutter head start-up course of i transverse beam system and cutter head termination procedure are modeled as respectively to the startup p of storehouse institute _{i, O}with the termination p of storehouse institute _{i, E}, start storehouse and comprise a token, repeat this step, get successively i=1 n;

2. to distributing in the interference region of i transverse beam system

individual contour segment

with interference region

individual outline section

cutting process, and in the interference region of i crossbeam

individual F.F. route segment

outside interference region

individual F.F. route segment

f.F. process, be modeled as respectively individual district internal cutting storehouse institute,

outside individual district, cut storehouse institute,

in individual district, F.F. storehouse in one's power

outside individual district F.F. storehouse and the sequencing of advancing according to crossbeam cutter head be designated as respectively p _{i, 1}, p _{i, 2}..., p _{i, s},

repeat this step, get successively i=1 n;

By the cutter head start-up course TO consuming time of i transverse beam system ⁱ, cutter head termination procedure TE consuming time ⁱ, give respectively and start the p of storehouse institute _{i, O}, stop the p of storehouse institute _{i, E}, contour segment in interference region

execution time

with interference region outline section

execution time

and F.F. route segment in interference region

execution time

with interference region extra income inbound path section

execution time be called the token retention time, give respectively p _{i, 1}, p _{i, 2}..., p _{i, s}the storehouse institute of middle correspondence, repeats this step, gets successively i=1 n;

3. add s+1 transition t _{i, 1}, t _{i, 2}..., t _{i, s}, t _{i, s+1}, then by p _{i, O}draw a directed arc and point to t _{i, 1}, t _{i, 1}draw a directed arc and point to p _{i, 1}, p _{i, 1}draw again a directed arc and point to t _{i, 2}, t _{i, 2}draw again a directed arc and point to p _{i, 2}, the like, until p _{i, s}draw a directed arc and point to t _{i, s+1}, t _{i, s+1}draw again a directed arc and point to p _{i, E}, repeat this step, get successively i=1 n, transition represent the end of a process and the beginning of next process, it is 1 that the weight on all directed arcs is composed, and obtains timing Petri pessimistic concurrency control;

4. n-1 interference region be modeled as respectively to n-1 resources bank institute and be labeled as respectively p ₁, p ₂..., p _n-1, and respectively place a token, by the internal cutting storehouse, all districts of arbitrary interference region of i transverse beam system in one's power in district F.F. storehouse in each storehouse preposition transition draw the resources bank institute that a directed arc points to described arbitrary interference region, and then by this resources bank draw respectively internal cutting storehouse, all districts that directed arc points to described arbitrary interference region in one's power in district F.F. storehouse in each storehouse preposition transition, repeat this step, get successively i=1, 2, n, Petri pessimistic concurrency control in the middle of forming, then by the middle Petri pessimistic concurrency control obtaining each comprise resources bank all directed arcs of self-loop delete, the final Petri pessimistic concurrency control that forms many cutting process,

H. utilize the Petri pessimistic concurrency control of above-mentioned many cutting process to carry out the simulation and analysis of many cutting process, to check the correctness of the coordination control strategy of many transverse beam system:

1. be the p of resources bank institute in the Petri pessimistic concurrency control of above-mentioned many cutting process ₁, p ₂..., p _n-1all rearmounted transition triggering priority is set:

If the priority of the i transverse beam system arranging in B3 step is greater than the priority of i+1 transverse beam system, the triggering priority that contains all rearmounted transition of i in subscript is greater than the triggering priority of all rearmounted transition that contain i+1 in subscript, otherwise, if the priority of the i transverse beam system arranging in B3 step is less than the priority of i+1 transverse beam system, the triggering priority that contains all rearmounted transition of i in subscript is less than the triggering triggering priority of all rearmounted transition that contain i+1 in subscript;

2. according to token play rules, progressively play in the Petri pessimistic concurrency control of many cutting process and respectively start the p of storehouse institute _{i, O}, the p of resources bank institute ₁, p ₂..., p _n-1in token, the many transverse beam system coordination control strategy described in step B3 is carried out to emulation check, until all p of termination storehouse institute _{i, E}all obtain token, described token play rules is as follows:

The triggering that one, token are play by transition drives, and first checks that all transition find out the transition that meet following trigger condition:

Condition one: each preposition storehouse of transition in token number be all more than or equal to 1;

Condition two: each preposition storehouse of transition in time of holding of token be more than or equal to the token retention time of giving;

Condition three: if also exist transition and current transition to have same preposition resources bank institute, and two transition all satisfy condition one, two triggering satisfies condition in these two transition, ungratifiedly do not trigger, if these two transition all satisfy condition two, allow the transition of high priority trigger according to the triggering priority arranging, the transition of low priority do not trigger;

The transition that two, meet trigger condition will trigger, and triggering will make each preposition storehouse of these transition lose a token, in all rearmounted storehouse institute of simultaneously these transition, add a token, realize a step of token and play;

If 3. in internal cutting Ku Suohe district, district corresponding to arbitrary interference region, F.F. storehouse only has one to hold token at any time at the most, show that many transverse beam system coordination control strategy is correct, after this can jump procedure B, by cooperative control device, carried out the coordination control strategy of many transverse beam system, otherwise be wrong, need to redesign coordination control strategy.

Compared with prior art, tool of the present invention has the following advantages and remarkable result:

(1) the invention provides a kind of on-line coordination for combination water cutting process controls and Petri net verification method, by reading online position and the velocity information of adjacent beams, dynamically the action of the crossbeam of decision competition interference region and the sequencing that arbitration enters interference region, avoid adjacent beams to bump in interference region;

(2) coordination control strategy that on-line coordination control method provided by the invention adopts and the NC code of cutting process are separate, user still can utilize the CAD that technical know-how in the past and experience are carried out workpiece to be cut to draw, then utilizing the inventive method to carry out cad file cuts apart, then import to respectively in water cutting CAM software feed path is set, and generate numerical control NC code, finally normally carry out NC code, only have when any a pair of adjacent beams system competition interference region, the control device that this coordination control strategy is installed just can be intervened on one's own initiative, avoid their collision to occur.

(3) control method for coordinating strong robustness provided by the invention, even if indivedual transverse beam system break down, this method also can be maintained remaining part continuation normal operation and be completed predetermined cutting task, for example in process, there is some accident, as a certain transverse beam system cutting head serious wear, only need this transverse beam system to stop and change cutting head, or certain section of profile is not only cut, only needing that this transverse beam system is carried out to rollback heavily cuts, and each remaining transverse beam system still continues cutting separately, be not affected, also dynamically being avoided of potential conflict.

(4) synchronous without each cutting process of on-line coordination control method provided by the invention, at any time, each transverse beam system can start independently, cutting, time-out, recovery, rollback are heavily cut or stop, and dirigibility is strong.

(5) the present invention also provides the method that adopts Petri net means to carry out simulating, verifying and analysis to many cutting process coordination control strategy.To given large work piece cut task, can will for it, set up Petri pessimistic concurrency control, by the token broadcasting mechanism of Petri net, the cutting process of simulating many transverse beam system, the correctness of check coordination control strategy, these checking means are effective, directly perceived, simple and easy.

Accompanying drawing explanation

The main process that the on-line coordination of many cross beam types of Fig. 1 water cutting process is controlled;

The two cross beam water diced systems of Fig. 2 and machining area thereof are divided;

Fig. 3 processing work to be cut and profile CAD example;

Fig. 4 the 1st transverse beam system cutting task and feed path setting;

Fig. 5 the 2nd transverse beam system cutting task and feed path setting;

The on-line coordination control strategy of Fig. 6 adjacent beams;

Fig. 7 the 1st crossbeam feed path segmentation markers;

Fig. 8 the 2nd crossbeam feed path segmentation markers;

The Petri pessimistic concurrency control of the two crossbeam cutting process of Fig. 9;

Embodiment

Below the specific embodiment of the present invention is elaborated, more clearly show whereby of the present invention and other object, Characteristics and advantages.

The present invention mentions a kind of on-line coordination control method of the diced system of the many cross beam waters for large-size workpiece cutting process.The large-size workpiece is here often referred to length at the workpiece to be cut of 3-12 rice, also comprise the workpiece that those length are greater than 12 meters, but the width of workpiece must be less than or equal to the width of many transverse beam system.Water jet cutting refers to and utilizes the agent of erosion of high-voltage and ultra-high water boundling to carry out the process of work piece cut.Each water cutting process is carried out by a transverse beam system (crossbeam and the water cutting head being installed on it or title nozzle), many cross beam types water diced system is exactly one and is spliced and combined and formed by a plurality of water cutting transverse beam system, guide rail, cutting bed, the cutting that can walk abreast of each adjacent beams, but joining place has overlapping processing district.Each transverse beam system is controlled by a CNC controller.

The present invention coordinates a plurality of water jet cutting process by online guiding and avoids collision, steadily complete concurrently cutting task, the on-line coordination of described combination water cutting process is controlled with Petri net verification method overall procedure and is provided by Fig. 1, first tackling given workpiece cad file to be cut cuts apart, the CAD son file forming imports the corresponding numerical control NC of CAM Software Create machining code, can design the coordination control strategy between each transverse beam system simultaneously, by NC file and coordination control strategy, carried out again the Petri net modeling of cutting process, after simulation analysis checking, the coordination of carrying out between NC code and each crossbeam is controlled.

Combination water cutting process of the present invention is to realize with many cross beam types water-jet cutting system, described many cross beam types water-jet cutting system comprise n transverse beam system and n transverse beam system along guide rail direction be arranged in order and be designated as the 1st transverse beam system, the 2nd transverse beam system ..., i transverse beam system ..., n transverse beam system, n is the transverse beam system sum in many cross beam types water-jet cutting system, n ∈ ⁺and n>=2, ⁺for the set of positive integer, i ∈ [1, n], each transverse beam system contains crossbeam and a computer numerical control (CNC) CNC system that is provided with water cutter head, it is characterized in that, and the method comprises the following steps:

A. the machining area of many cross beam types water diced system is divided:

Respectively by the 1st transverse beam system, the 2nd transverse beam system, i transverse beam system, the maximum region that each crossbeam motion in n transverse beam system covers, as the 1st accessoble region, the 2nd accessoble region, i accessoble region, n1 accessoble region, n1=n, using the lap of adjacent j accessoble region and j+1 accessoble region as j overlay region, j ∈ [1, n-1], j overlay region is along two boundary lines of guide rail direction, be called left double line and the right double line of j overlay region, respectively by the 1st overlay region, the 2nd overlay region, the both sides of n2-1 overlay region respectively increase the width of a crossbeam along guide rail, form the 1st interference region, the 2nd interference region, n2-1 interference region, n2=n, by the 1st interference region, the 2nd interference region, n2-1 interference region is along two boundary lines of guide rail direction, be called the 1st left interference line in interference region and right interference line, the 2nd left interference line in interference region and right interference line, the left interference line in n2-1 interference region and right interference line.

Fig. 2 has provided the example of two cross beam water diced systems, comprises the 1st transverse beam system and the 2nd transverse beam system, and each crossbeam is provided with a water cutter head.According to steps A, the accessoble region of two transverse beam system is labeled as respectively the 1st accessoble region and the 2nd accessoble region, and overlay region and interference region all only have one, are labeled as overlay region 1 and interference region 1, and interference region 1 exists two interference line in left and right.

Fig. 3 has provided the CAD figure of a workpiece to be cut, needs cutting profile to be numbered respectively 1,2,3,4, and according to the mentioned principle judgement of step B11, profile 1 is positioned at the region outside the 1st overlay region of the 1st accessoble region, should distribute to the 1st transverse beam system; Profile 2 is positioned at the 1st accessoble region and profile to be cut starts from the 1st overlay region, terminates in outside the 1st overlay region, should distribute to the 1st transverse beam system; And profile 3 is crossed over the 1st overlay regions, the center line of overlapping interference region of its leap of take is boundary, it is divided into the 1st section, the 2nd section along guide rail direction distribute to respectively the 1st transverse beam system, the 2nd transverse beam system; In addition, profile 4 is positioned at the 1st overlay region completely, and profile 4 not only can be distributed to the 1st transverse beam system but also can distribute to the 2nd transverse beam system, and assignment of allocation is given the 2nd transverse beam system here.Original CAD can be divided into two CAD son files like this, referring to Fig. 4, Fig. 5.

Support the computer auxiliaring manufacturing CAM software of various water-jet machines, as NewCAM, CATIA, there is the input of arranging to cut the interface of these technological parameters consuming time of setup time, cutting speed, fast forward speed, water and abrasive material valve Push And Release, plane drawing function is also provided, start-up point, the terminating point of water cutter head, the point of penetration of each profile of water cutter head can be set visually and cut out the sequencing of point, each contour machining, in Fig. 4, Fig. 5, provided respectively a kind of feed path of the 1st, 2 transverse beam system, s _a, e _awith s _b, e _bbe respectively start-up point, the terminating point of the 1st, 2 crossbeam cutter heads, with the dotted line a of arrow _i(i=1,2 ..., 4), b _j(j=1,2,3) represent respectively the fast inbound path of the 1st, 2 crossbeams, for sealing profile, point of penetration and cut out a little identical, as profile 1, for opening profile difference, as the left-half 3a of profile 3, its point of penetration is at directed line segment a ₃terminal, cut out a little at directed line segment a ₄starting point.These information are all partly set at CAM.The cutting task of Fig. 4 for example, can arrange following feed path: first, and from s _astart F.F. a ₁section, the point of penetration rear enclosed cutting profile 1 of arrival profile 1, exits by cutting out point (same point of penetration) after cutting, and F.F. a ₃section, until the point of penetration of profile 2 sealing cutting profile 2, after cutting by same point withdrawing, F.F. a then ₄section, to the point of penetration of profile 3a, starts the open profile 3a of cutting until cut, and then by the last point (cutting out a little) of 3a, is fast-forward to the terminating point e of water cutter head _a(with start-up point s _a), the feed path setting of such the 1st crossbeam completes, for the feed path of the 2nd crossbeam, can arrange after the same method, as shown in Figure 5, s _b-F.F. b ₁-cutting profile 4-F.F. b ₂-cutting profile 3b (right half part of profile 3)-F.F. b ₃-e _b., then use the post processor of CAM software to process, generate the NC machining code of the 1st, 2 transverse beam system.It is below one section of numerical control NC code of the 1st transverse beam system, therefrom can find out water cutter head start-up point, the terminating point of water cutter head, the point of penetration of profile of setting and cut out a little, and these technological parameters consuming time of the cutting setup time, cutting speed, fast forward speed, water and the abrasive material valve Push And Release that arrange will be built in the CNC controller of transverse beam system, not visible herein.

G91

The start-up point of G92 X0.Y0. // water cutter head is (0,0)

G01 X-117.187 Y-85.141//profile 1 point of penetration

X44.761?Y-137.762

X144.851

X44.762?Y137.762

X-117.187 Y85.141//profile 1 cuts out a little

The terminating point of G00 X500.Y0//water cutter head is (500,0)

M30

The sequencing of the numerical control NC code of profile cut has reflected the sequencing of the cutting of profile.

Time-out in above-mentioned situation one, two can be that F.F. suspends and cutting suspends, and for cutting, suspends and is conventionally accompanied by closing of abrasive material and water under high pressure valve.In many transverse beam system, the flow process of the on-line coordination control strategy of any two adjacent beams is provided by Fig. 6.The cutting task that Fig. 4 and Fig. 5 provide of take is example, supposes to set the priority of the 1st transverse beam system higher than the priority of the 2nd transverse beam system.By fast forward speed V, transverse beam system positional information read cycle τ, substitution D=V τ, can obtain calculating critical distance.

After cooperative control device starts, cooperative control device starts to read position and speed and the direction of each transverse beam system via each CNC controller circulation simultaneously, and calculates critical distance D=V τ, meets step B3 1..

The 1st transverse beam system is at F.F. a ₁in, the 2nd transverse beam system is at F.F. process b ₁in, now the 1st transverse beam system and interference line l _ldistance, the 2nd transverse beam system and interference line l _rdistance be all greater than critical distance D, 2. the NC code of carry out subscribing, meet step B3.

The 2nd transverse beam system is advanced to interference region, and the 2nd transverse beam system and interference line l _rdistance be less than critical distance D, now the 1st adjacent transverse beam system is also at F.F. process a ₁in, and estimate that the 1st transverse beam system enters interference region by complete F.F. process in interference region and cutting process in the 2nd transverse beam system after, the 2nd transverse beam system keeps current motion, enters interference region, the 1st transverse beam system keeps current motion, meet step B3 3. in the first in situation one.

After this period of time, the 1st transverse beam system completes F.F. process and cutting process outside interference region, and now just outside interference region, cutting profile 2, the 2 transverse beam system have completed F.F. process and the cutting process in interference region, now cutting profile 3b outside interference region just.The 1st transverse beam system is advanced to interference region, and the 1st transverse beam system and interference line l _ldistance be less than critical distance D, the 2nd transverse beam system cutting profile 3b outside interference region just now, and estimate that the 2nd transverse beam system will enter interference region before the 1st transverse beam system completes the cutting profile 2 in interference region, the 1st transverse beam system keeps current motion, the 2nd transverse beam system is suspended.After this, the 2nd transverse beam system is suspended always, because the 1st transverse beam system is just in interference region, until the cutting process that the 1st transverse beam system completes in interference region exits interference region completely, recover the motion before the 2nd transverse beam system is suspended, continue cutting profile 3b, meet the second case in the 3. situation two of step B3.

The 1st transverse beam system is at F.F. process a ₃, with interference line l _ldistance be less than critical distance D, and the 2nd adjacent transverse beam system is at cutting profile 3b, with interference line l _rdistance be also less than critical distance D, now according to predefined priority, the 1st transverse beam system is introduced into interference region, the 2nd transverse beam system is suspended, until the 1st transverse beam system completes F.F. process and cutting process in interference region, exit interference region completely, recover the motion before the 2nd transverse beam system is suspended, enter interference region, meet the 3. situation three of step B3.

Coordination control strategy will be embodied as executable software, is arranged in cooperative control device, detects Position And Velocity and the direction of each crossbeam, and coordinates and collision prevention according to predetermined strategy.For two transverse beam system, the variable set up of corresponding crossbeam number in coordination control strategy need be become to 2.

C. above-mentioned cooperative control device is that the industrial control computer of carrying out many transverse beam system coordination control strategy, journey logic controller PLC able to programme, embedded controller or other have the electronic installation of calculating, storage unit and known communication interface.

Described cooperative control device can be that the industrial control computer that can move executable coordination control program, journey logic controller PLC able to programme, embedded controller or other have the electronic installation of calculating, storage unit and known communication interface, and form master slave control structure with CNC controller, be that cooperative control device is main, and CNC controller be from, by known communication interface, cooperative control device carries out data acquisition and control to each CNC system.

Owing to the present invention relates to Petri net, at this, we provide the related notion of Petri net:

Definition 1:Petri web frame is defined as quaternary formula N=(P, T, F, W), and wherein P is that limited Suo Ji， storehouse, storehouse reason circle (zero) represents, T is limited transition collection, and transition are slightly horizontal represent, make

and

for the set of directed arc (flow relation), and W:F → (set of nonnegative integer) is weighting function, if (, *) ∈ is F, w (, *) > 0, if

w (, *)=0, (, *) is storehouse and transition (or transition and storehouse institute) right here.N is called ordinary, if the weight of its all arcs is 1, now N can note by abridging into N=(P, T, F), wherein F:(P * T) ∪ (T * P) → { 0,1}.The preposition storehouse of transition t ∈ T collects (rearmounted storehouse collects) and is defined as ^.t={p ∈ P|w (p, t) > 0} (t ^.=p ∈ P|w (t, p) > 0}), similarly, the preposition transition collection of the p ∈ P of storehouse institute (rearmounted transition collection) is defined as ^.p={t ∈ T|w (t, p) > 0} (p ^.=p ∈ P|w (p, t) > 0}).

Definition 2: mark Petri net is defined as dualistic formula G=(N, M ₀), wherein N is Petri web frame, M ₀for initial marking.The sign M of N is G's | the sign of P| dimension, and M:P → and component M (p) represent the contained token number of the p of storehouse institute, diagram is by " " of respective number or directly by numeral.

Definition 3: the sequence p of storehouse institute and transition in mark Petri net G ₁t ₁p ₂t ₂t _n-1p _n(t ₁p ₁t ₂p _n-1t _n) be called p ₁to p _n(t ₁to t _n) directed walk, if for

and t _i∈ ^.p _i+1(

and p _i∈ ^.t _i+1), 1≤i≤n-1 wherein.If there is not the node of repetition in directed walk, claim that this path is basic directed walk, if the head and the tail node of basic directed walk is identical, claim that this basic directed walk is basic directed circuit, if only have a storehouse institute and transition in basic directed circuit, be called self-loop.

The dynamic of definition 4:Petri net shows as token and plays, token storehouse in flow, the basic broadcasting of token is determined by following rule:

1) transition t is authorized under certain sign, and if only if M (p)>=w (p, t),

2) authorized transition can trigger, and the triggering of the transition t authorizing under M in sign will cause new sign M ', wherein M ' (p)=M (p)-w (p, t)+w (t, p),

The play rules of token can be expanded according to actual conditions.Token is play can the generation of modeling event or the execution of operation, so Petri net can be for analyzing the dynamic behaviour of the system that be modeled.It is worthy of note, above-mentioned token play rules is applicable above-mentioned classical Petri net only, and along with the difference of application, if need expand Petri net, for example, to transition or time that give in storehouse, token play rules will adjust to some extent.The mechanism of in the present invention, Petri net and token thereof being play is for carrying out modeling, emulation and analysis, the correctness of check coordination control strategy to many crossbeams cutting process.

Preferentially, the on-line coordination of described many cross beam waters diced system cutting process is controlled and Petri net verification method, it is characterized in that, the method also comprises the Petri net modeling and simulation verification step of coordination control strategy in step B3:

Preparatory function G instruction code described in above-mentioned steps D and subsidiary function M instruction code, mainly contain following several:

G00----locates fast; G01----linear interpolation

G03----is circular interpolation G03----clockwise direction circular interpolation counterclockwise

G04----regularly suspends the programming of G91----relative coordinate

M73----opens water under high pressure M74----and stops water under high pressure

M75----opens abrasive material M76---and closes abrasive material

Read 2 numerical control NC code files that crossbeam is corresponding, to extract cutting profile information, extract the information such as G function code, size and subsidiary function of controlling crossbeam motion, obtain accordingly the point of penetration and the precedence that cuts out point, profile cut of terminating point, each profile and each profile of each water cutter head start-up point, water cutter head, the path that finally feed path of definite each transverse beam system comprises F.F. and cutting.For example, to aforesaid numerical control NC code,

G91

The start-up point of G92 X0.Y0. // water cutter head is (0,0)

G01 X-117.187 Y-85.141//profile 1 point of penetration

X44.761?Y-137.762

X144.851

X44.762?Y137.762

X-117.187 Y85.141//profile 1 cuts out a little

The terminating point of G00 X500.Y0//water cutter head is (500,0)

M30

Can, by reading text, extract respectively water outlet cutter head start-up point, the terminating point of water cutter head, the point of penetration of profile and cut out a little.The sequencing of the cutting of profile is determined by the sequencing of the numerical control NC code of profile.

1 \leq α \leq m_{1}^{i},

1 \leq β \leq m_{2}^{i},

1 \leq χ \leq l_{1}^{i},

1 \leq γ \leq l_{2}^{i},

In step e, for certain crossbeam, its profile can only be crossed at most an interference line, because be positioned at the accessoble region of this crossbeam, only has an interference line.According to step B, by the cutting of the 1st transverse beam system with fast inbound path according to the sequencing of processing the left interference line l with interference region 1 _lfor boundary carries out dividing mark, as shown in Figure 7, in interference region, contour segment and interference region outline section are labeled as respectively

1≤α≤3,1≤β≤4, wherein

represent the cutting path of profile 1,

the segmentation markers of profile 2 cutting paths,

with for the outer part in interference region 1, and

for part in interference region, similar,

be the segmentation markers of the cutting path of profile 3a, in the interference region of the 1st crossbeam, F.F. route segment and interference region extra income inbound path section are labeled as respectively

1≤χ≤2,1≤γ≤4; In like manner, as Fig. 8, with the right interference line of interference region 1, can be labeled as respectively cutting footpath section outside the interference region internal cutting route segment of the 2nd crossbeam and interference region

with

f.F. route segment in the interference region of the 2nd crossbeam and interference region extra income inbound path section are labeled as respectively

with

respectively with

corresponding one by one, and in the interference region of i transverse beam system the execution time of F.F. route segment and interference region extra income inbound path section be designated as respectively respectively with

corresponding one by one;

For this step, cutter head start-up course consuming time cut setup time and added that the unlatching of water and abrasive material is consuming time, and cutter head termination procedure is consuming time, and to be taken as closing of water and abrasive material consuming time; If a certain F.F. path is d, and cutting profile length is f, is v in known fast forward speed _f, cutting speed is v _c, have F.F. execution time tf and cutting execution time t _cby following formula, calculated:

t_{f} = \frac{d}{v_{f}},

t_{c} = \frac{f}{v_{c}}

According to this, can set up respectively the cutter head start-up course TO consuming time of the 1st crossbeam ¹with cutter head termination procedure TE consuming time ¹, in feed path, in interference region, the execution time of contour segment and interference region outline section is designated as respectively

1≤α≤4,1≤β≤3,

respectively with

and in the interference region of the 1st crossbeam the execution time of F.F. route segment and interference region extra income inbound path section be designated as respectively

1≤χ≤4,1≤γ≤2, respectively with

corresponding one by one; The cutter head start-up course that can establish equally the 2nd crossbeam is consuming time consuming time with cutter head termination procedure, the execution time of contour segment and interference region outline section in interference region in feed path, and execution time of F.F. route segment and interference region extra income inbound path section in interference region.

2. to distributing in the interference region of i transverse beam system

individual contour segment

with interference region

individual outline section

cutting process, and in the interference region of i crossbeam

individual F.F. route segment

outside interference region

individual F.F. route segment

outside individual district, cut storehouse institute,

in individual district, F.F. storehouse in one's power

repeat this step, get successively i=1 n;

execution time

with interference region outline section

execution time

and F.F. route segment in interference region

execution time

with interference region extra income inbound path section

execution time

be called the token retention time, give respectively p _{i, 1}, p _{i, 2}..., p _{i, s}the storehouse institute of middle correspondence, repeats this step, gets successively i=1 n;

4. n-1 interference region be modeled as respectively to n-1 resources bank institute and be labeled as respectively p ₁, p ₂..., p _n-1, and respectively place a token, by the internal cutting storehouse, all districts of arbitrary interference region of i transverse beam system in one's power in district F.F. storehouse in each storehouse rearmounted transition draw the resources bank institute that a directed arc points to described arbitrary interference region, and then by this resources bank draw respectively internal cutting storehouse, all districts that directed arc points to described arbitrary interference region in one's power in district F.F. storehouse in each storehouse preposition transition, repeat this step, get successively i=1, 2, n, Petri pessimistic concurrency control in the middle of forming, then by the middle Petri pessimistic concurrency control obtaining each comprise resources bank all directed arcs of self-loop delete, the final Petri pessimistic concurrency control that forms many cutting process,

According to step G, to the cutting task shown in Fig. 3, can progressively set up the Petri pessimistic concurrency control of two cross beam water cutting process: first, the cutter head of the 1st transverse beam system and the 2nd transverse beam system is started and cutter head termination procedure, be modeled as respectively and start the p of storehouse institute _{1, O}with the termination p of storehouse institute _{1, E}, start the p of storehouse institute _{2, O}with the termination p of storehouse institute _{2, E}, start the p of storehouse institute _{1, O}, p _{2, O}, respectively comprise a token, as shown in Figure 9; Then, to contour segment in the interference region of the i crossbeam shown in Fig. 7 and Fig. 8

with interference region outline section

cutting process, and F.F. route segment in interference region

with interference region extra income inbound path section

f.F. process, be modeled as seriatim storehouse institute, and the sequencing of advancing according to crossbeam cutter head is designated as respectively p _{i, 1}, p _{i, 2}..., p _{i, s}here i gets respectively 1,2, each storehouse implication by table 1, provided:

Storehouse institute and meaning thereof in the Petri pessimistic concurrency control of table 1 pair cross beam water cutting process

P _{1, O}t _1,1p _1,1... p _1,13t _1,14p _{1, E}; For the 2nd crossbeam, carry out equally this process, obtain transition t _2,1, t _2,2..., t _2,9, t _2,10with some directed arcs, form by p _{i, O}point to p _{i, E}basic directed walk p _{2, O}t _2,1p _2,1... p _2,9t _2,10p _{1, E}, referring to Fig. 9;

Finally, the unique interference region for two transverse beam system is modeled as 1 resources bank institute, p ₁, by the contour segment in all interference regions of the 1st crossbeam and the fast corresponding storehouse p of institute of inbound path _1,5, p _1,8, p _1,9, p _1,11, p _1,12preposition transition t _1,5, t _1,8, t _1,9, t _1,11, t _1,12, draw respectively the p of resources bank institute that a directed arc points to corresponding interference region 1 ₁, and then by the p of resources bank institute of corresponding interference region 1 ₁draw respectively a directed arc and point to p _1,5, p _1,8, p _1,9, p _1,11, p _1,12preposition transition, for the 2nd crossbeam, repeat respectively this step, then check and in the Petri pessimistic concurrency control obtaining, comprise the p of resources bank institute ₁self-loop, have p ₁t _1,9p ₁, p ₁t _1,12p ₁, p ₁t _2,3p ₁, p ₁t _2,4p ₁, p ₁t _2,5p ₁, p ₁t _2,8p ₁, be the structure of redundancy, for two processes in interference region, as p _1,8, p _1,9unnecessaryly complete previous process p _1,8the rear interference region resource that first discharges is carried out p again _1,9, because both do not leave interference region, therefore these self-loops being disconnected, the directed arc being about to is wherein deleted, and finally forms the Petri pessimistic concurrency control of many cutting process, as shown in Figure 9.

Here we prove that set up Petri pessimistic concurrency control can verify the correctness of coordination control strategy first.The Petri pessimistic concurrency control of setting up if can prove and the logic of designed coordination control strategy are unanimously just can prove proposition.First, for the cutting outside interference region or F.F., according to prefabricated NC code, carry out completely, coordination control strategy is not intervened them, process flow diagram Fig. 6 referring to coordination control strategy, and NC code is carried out according to the feed path order partly arranging at CAM and execution time cut or F.F. completely, this point is embodied completely in Petri pessimistic concurrency control, Petri pessimistic concurrency control carrys out modeling according to feed path order, and included the execution time in the cutting of expression operation process or F.F. storehouse institute, performed time of this storehouse and actual cutting or F.F. are consuming time is one to one, secondly, in coordination control strategy, to entering with the processing mode of adjacent beams system and the logic of Petri pessimistic concurrency control in interference region operation just, be consistent, be for the transverse beam system that first approaches this interference region, will be introduced into interference region operation in coordination control strategy, or the advanced person of high priority when adjacent two crossbeams all tend to same interference region (being less than critical distance) simultaneously, and just the crossbeam of interference region operation should continue operation until after completing adjacent crossbeam just can enter, these have reflected in fact in any interference region that a moment can only have at most a transverse beam system to exist, so just, avoided collision, and in Petri pessimistic concurrency control due in transition trigger condition, included in preposition storehouse execution time and trigger priority, can reflect the priority level of closing on the cutting of interference region or the sequencing of the arrival left and right interference line of F.F. process and the execution of the cutting in interference region or F.F. process, thereby make internal cutting storehouse, district institute or the F.F. of corresponding a pair of adjacent beams system and same interference region respectively can only have at the most at any time one containing token, this has also showed the same fact, be that actual operation process is can be simultaneously in interference region, thereby avoid the generation of collision.

To sum up, can prove that set up Petri pessimistic concurrency control is consistent with the logic of designed coordination control strategy, the Petri pessimistic concurrency control of therefore setting up can be verified the correctness of coordination control strategy.Next the Fig. 9 of two transverse beam system of take is the process of the Petri pessimistic concurrency control checking control method for coordinating correctness of example explanation based on being set up.During beginning, the p of storehouse institute of the 1st transverse beam system _{2, O}middle token number is 1, now transition t _2,1the preposition storehouse p of institute _{2, O}middle token number is greater than 1, the preposition storehouse p of institute of these transition _{2, O}the time of holding of middle token has been more than or equal to the token retention time TO giving ¹, so transition t _2,1there is the preposition storehouse p of institute _{2, O}lose a token, the rearmounted storehouse p of institute of these transition simultaneously _1,1token of middle interpolation, thus realize the broadcasting of token, and the feed order outside the interference region of expection is consistent like this.Suppose the p of storehouse institute _{isosorbide-5-Nitrae}, the p of storehouse institute _2,1token number be all 1, transition t now _1,5, t _2,2each preposition storehouse in token number be all more than or equal to 1, the p of storehouse institute _{isosorbide-5-Nitrae}, the p of storehouse institute _2,1token holding time be all more than or equal to the token retention time of giving

need to, according to the size of the triggering right of priority arranging, allow the transition of high priority preferentially trigger, transition t _2,2there is the preposition storehouse p of institute of these transition _2,1, p ₁lose token, the rearmounted storehouse p of institute _2,2obtain token, enter interference region, the t of transition simultaneously _1,5because the preposition storehouse p of institute ₁token number is 0 can not occur, such the 1st transverse beam system and the 2nd transverse beam system just can not bump in interference region 1, in like manner can allow token continue to play, internal cutting storehouse, district institute or the F.F. that can observe interference region 1 can only have one at any time at the most containing token, the result that is emulation shows that actual operation process is can be simultaneously in interference region, thereby avoid the generation of collision, this has just verified that coordination control strategy is correct.

Claims

1. the on-line coordination of a combination water cutting process is controlled and Petri net verification method, described combination water cutting process is to realize with many cross beam types water-jet cutting system, described many cross beam types water-jet cutting system comprise n transverse beam system and n transverse beam system along guide rail direction be arranged in order and be designated as the 1st transverse beam system, the 2nd transverse beam system ..., i transverse beam system ..., n transverse beam system, n is the transverse beam system sum in many cross beam types water-jet cutting system

and n>=2,

for the set of positive integer, i ∈ [1, n], each transverse beam system contains crossbeam and a computer numerical control (CNC) CNC system that is provided with water cutter head, it is characterized in that, and the method comprises the following steps:

A. the machining area of many cross beam types water diced system is divided:

B12. for continuous leap j overlay region, j+1 overlay region ..., j+k-1 overlay region profile to be cut, j, k ∈ [1, n-1] and i+k ∈ [2, n], the overlay region number that representative is crossed over, the center line of each overlapping interference region that the profile to be cut of take is crossed over is boundary, by profile to be cut along guide rail direction be divided into j section, j+1 section ..., j+k-1 section, j+k section, each contour segment to be cut after cutting apart distribute to respectively j transverse beam system, j+1 transverse beam system ..., j+k-1 transverse beam system, j+k transverse beam system;

B2. each CAD son file further imports the auxiliary CAM of manufacture of water cutting calculations machine software, generates executable numerical control NC code file:

Once 3. X transverse beam system is advanced to i interference region, and when the distance of the nearest interference line of X transverse beam system and i interference region is less than critical distance, according to following disposal methods, to avoid the collision of any two adjacent transverse beam system to occur, described critical distance is coordinate to control a transverse beam system allowing to the minor increment of closing on a nearest interference line of interference region, be designated as D=V. τ, wherein V is that fast forward speed, τ are the cycle period that cooperative control device reads transverse beam system positional information, and described disposal route is:

C. above-mentioned cooperative control device is that the industrial control computer of carrying out many transverse beam system coordination control strategy, programmable logic controller (PLC) PLC, embedded controller or other have the electronic installation of calculating, storage unit and known communication interface.

2. the on-line coordination of combination water cutting process according to claim 1 is controlled and Petri net verification method, it is characterized in that, the method also comprises the Petri net modeling and simulation verification step of coordination control strategy in step B3:

respectively with

respectively with

corresponding one by one;

1. the cutter head start-up course of i transverse beam system and cutter head termination procedure are modeled as respectively to the startup p of storehouse institute _{i, O}with the termination p of storehouse institute _{i, E}, start storehouse and comprise a token, repeat this step, get successively i=1～n;

2. to distributing in the interference region of i transverse beam system

individual contour segment outside interference region

individual contour segment

cutting process, and in the interference region of i crossbeam individual F.F. route segment

outside interference region

individual F.F. route segment f.F. process, be modeled as respectively

individual district internal cutting storehouse institute,

outside individual district, cut storehouse institute, in individual district, F.F. storehouse in one's power

repeat this step, get successively i=1～n;

execution time with interference region outline section

execution time

and F.F. route segment in interference region

execution time with interference region extra income inbound path section

execution time

be called the token retention time, give respectively p _{i, l}, p _{i, 2}..., p _{i, s}the storehouse institute of middle correspondence, repeats this step, gets successively i=1～n;

3. add s+1 transition t _{i, l}, t _{i, 2}..., t _{i, s}, t _{i, s+1}, then by p _{i, O}draw a directed arc and point to t _{i, l}, t _{i, 1}draw a directed arc and point to p _{i, l}, p _{i, 1}draw again a directed arc and point to t _{i, 2}, t _{i, 2}draw again a directed arc and point to p _{i, 2}, the like, until p _{i, s}draw a directed arc and point to t _{i, s+1}, t _{i, s+1}draw again a directed arc and point to p _{i, E}, repeat this step, get successively i=1～n, transition represent the end of a process and the beginning of next process, it is 1 that the weight on all directed arcs is composed, and obtains timing Petri pessimistic concurrency control;

If the priority of the i transverse beam system arranging in B3 step is greater than the priority of i+1 transverse beam system, the triggering priority that contains all rearmounted transition of i in subscript is greater than the triggering priority of all rearmounted transition that contain i+1 in subscript, otherwise, if the priority of the i transverse beam system arranging in B3 step is less than the priority of i+1 transverse beam system, the triggering priority that contains all rearmounted transition of i in subscript is less than the triggering priority of all rearmounted transition that contain i+1 in subscript;