RU2765835C1 - Method and system for decentralized autonomous synchronization of interaction of digital mobile objects - Google Patents

Abstract

FIELD: computer technology; computing devices.

SUBSTANCE: method for decentralized autonomous synchronization of interaction of digital mobile objects is characterized by that in a group of objects O_i ordered by 0≤i≤n and object MS, in the absence of signal reception, objects send a signal S of a fixed duration T to MS during a given time interval, not less than a time interval of signal distribution between any O_i and MS objects, and, at a moment of termination of signal S reception, an object O₀ sends a signal or a message S_0ms of duration ^*T to the object MS, and each other O_i object, when receiving a signal S_(i-1)ms from an object O_i-1, similar to S_0ms, also sends a signal S_ims, similar to S_0ms with a delay of τ=i(2T+^*Τ), and all objects measure a time interval T_ims between the beginning of sending S_ims and the beginning of reception returned from MS, sends a signal Sk to MS, which MS returns with non-directional signals as ^*Sk to all O_i, and O_i having a value T_ims send a delayed signal S_t to MS within an interval T_ƒ, receive a signal ^*S_t from MS – a copy of the signal S_t, and adjust their movement according to the time interval between reception of ^*S_t and S_t.

EFFECT: increase in the accuracy of synchronization of interaction of mobile objects.

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Description

The invention relates to the field of computer technology, in particular to methods and technical means for decentralized autonomous synchronization of the interaction of digital mobile objects, in order to accelerate distributed computing performed by objects.

Known used as a prototype for the method and system RU 2 697 729 C1, 08/19/2019 "Method and system for managing the interaction of autonomous mobile technical objects with a quick response to changes in the state of objects and the environment."

In the prototype for synchronizing the actions of mobile objects, a measurement method is proposed that organizes for each object the measurement of the time interval for signal transfer from it to a dedicated mobile object - the MS communication module (hereinafter, instead of "signal transfer time interval" in the text, a shorter "distance" will be used).

Between measurement and use, distances change due to the movement of objects. This difference affects the synchronization accuracy. The prototype does not take measures to reduce this difference. At low speeds of movement of objects, this difference usually does not require the use of additional actions. However, for high-speed moving objects, additional steps are required to account for changing distances.

The task of accurate correction of distance changes is performed by the proposed patent, which contains a method and a system of technical means that remove the specified restriction for a system of objects of the following type.

In an ordered group of objects, all or part of the objects are moved. Each object of the group must measure the distance to the given MS object, and based on this measurement, synchronize the actions of the objects. The method for determining the distance of the group object from the MS is not the subject of the present invention and may not differ from the method of the prototype, but to determine changes in distance, the objects must exchange signals with the MS in a special way described below.

The objective of the present invention for the method is to quickly determine the timing and correct it for fast moving objects that are not in the prototype.

The technical result of the method is that each mobile object of the group synchronizes the actions of all objects of the group, and the objects of the group measure the distance to the mobile object MS with the following condition.

The distances between the mobile objects of the group and the MS obtained at the time of measurement should be corrected so that they do not differ within the specified allowable value from the real distances at the time they are used by the system objects.

The technical result for the method is achieved by the fact that the method of decentralized autonomous synchronization of the interaction of digital mobile objects is characterized by the fact that in a group of objects O _i ordered by 0≤i≤n and an MS object, in the absence of signal reception within a given time interval, the objects send a signal to the MS S of a fixed duration T, not less than the signal propagation time interval between any objects O _i and MS, and, at the moment when the signal S is stopped, the object O ₀ sends to the MS object a signal or message S _{0ms of} duration ^* T, and each other object O _i , when receiving a signal S _(i-1)ms similar to S _0ms from an object O _i-1 , it also sends a signal S _ims similar to S _0ms with a delay τ=i(2T+ ^* T) and all objects measure the time interval T _ims between the start of sending S _ims and the start of receiving the signal or message returned from the MS ^* S _ims , while the object O ₀ , having received the value T _0ms , sends a signal (or command) Sk to the MS, which the MS sends with non-directional signals rotates as ^* Sk to all O _i , and O _i having the value T _ims , send to the MS within the interval T _ƒ the signal S _t with a delay D=2(T _max -T _ims )+iT _ƒ , receive the signal ^* S from the MS _t is a copy of the signal S _t , and according to the time interval between receiving ^* S _t and S _t correct their movement.

The objective of the present invention for the system is to develop a system structure consisting of a group of technical devices that measure and correct the measured distances between the objects of the group and MS so that they do not differ within a given allowable value from the real distances at the time they are used by the objects of the system and provide the required synchronization accuracy of object actions.

The technical result for the system is that in order to improve the accuracy of synchronization of objects, the set of technical means of the system and the connections between them determines and corrects changes in the distances of the group objects relative to the MS object.

The technical result for the system is achieved by the fact that the system for decentralized autonomous synchronization of the interaction of digital mobile objects is characterized by the fact that the system consists of a group O of objects O _i ordered by 0≤i≤n and an MS object combined with it by wireless communication channels, each object O _i has a source U ₁ sent to the objects O to the receivers U _{2 of} the wireless signal S, has an indicator U _{3 of} the completion of receiving the signal S, has sources U ₃ , U ₆ , U ₈ sent to the object MS to the receivers U ₁₁ , U ₁₃ , U ₁₅ respectively signals S _ims , S _sp , S _t , has receivers U ₅ , U ₇ , U ₉ sent by sources U ₁₂ , U ₁₄ , U ₁₆ of the MS object, respectively signals ^* S _ims , ^* S _sp , ^* S _t , has a block control U ₁₀ connected by communication lines with blocks U ₁ -U ₉ and with an external device With, organizing through U ₆ communication between O and MS.

The technical essence and principle of operation of the proposed device of the system is illustrated by drawings.

Fig. 1. Phase of group synchronization.

Fig. 2. Decentralized offline synchronization system

The devices shown in the drawing should be considered as examples of the technical implementation of the device proposed in the patent.

A brief description of the method for decentralized autonomous synchronization of the interaction of digital mobile objects. The method consists of two phases: the first group synchronization phase (SP ₀ ) measuring the distance between the objects of the moving group of objects O and the object MS and the second phase of distance correction (SP), which uses the actions of the first phase. When SP ₀ receives the value of a specific distance between objects, SP begins to monitor changes in distances. At this point in time, SP is received from SP ₀ : T _max is the maximum time greater than or equal to the signal travel time between any objects; T _ims is the signal travel time between the object O _i of the troupe O and the object MS. During operation, SPs use signals qualitatively different from those of SP ₀ . Therefore, the signals SP ₀ and SP do not introduce mutual interference, they work in different channels.

In SP, in order to determine the change in distances between the ordered objects O _i and the object MS, an arbitrary object from O determines whether to start correcting the measured distance and starts the following process of observing the change in distance caused by the object's movement.

A brief description of the decentralized autonomous synchronization system for the interaction of digital mobile objects. To synchronize the interaction between the mobile objects of the group O and the MS object, all objects O _i from the group O and MS are combined by wireless non-directional radio or optical communication channels. The MS entity has the facilities to receive signals from O _i and send signals to O _i . Objects O _i have means for exchanging signals with objects O _i and MS, as well as a control unit that controls the transmission and reception of these signals and communication for signal exchange with an external device.

Detailed description of the proposed method.

The method consists of two phases: the first initial group synchronization phase (SP ₀ ) between the objects of the mobile group of objects O and the object MS and the second phase of the synchronization correction (SP), which uses the actions of the first phase.

In the first SP ₀ group synchronization method, any entity ¹ O _i sends a signal addressed to the MS to determine the signaling time T _ims and the distance between the group entity and the MS. Each O _i acts autonomously, without requiring control from any other objects of the system or external means.

Group synchronization is performed in a communication channel dedicated only to it. The signals in this channel do not affect the signals of other channels.

It is assumed that the objects are quasi-stationary and during the execution of all the required measurements, the movement of objects does not affect the specified measurement accuracy.

But in the method, any object corrects its synchronization only after the completion of the next group synchronization by all objects of the system. Synchronization error accumulates, which reduces the synchronization accuracy of fast objects.

Possibilities of objects Ο _i and MS, their interaction. Objects O _i and MS have the means to transmit and receive wireless non-directional optical or radio signals. There are two types of MS objects. The first type of MS receives a non-directional signal S _ims from O _i and in response sends a signal S _ims to all objects O _i also non-directional.

The second type of object MS works only with optical signals and simply reflects the signal in the direction of the object O _i that sent the signal S _ims , i.e. is a passive device - a retroreflector. Since the signals of objects O _i are omnidirectional, their source does not need information about the location of the receiver.

The objects O _i of the group of objects O are ordered, 0≤i≤n. Objects use three types of signals - S, S _ims , ^* S _ims , specified below. All signals are non-directional (except ^* S _ims retroreflector signals). Given the time interval T, sufficient to transfer signals between any objects - O _i and MS.

The SP ₀ process consists of four steps.

Step 1. The objects of group O detect the absence of signals S, S _ims , ^* S _ims during a given time interval not less than T and go to step 2.

Step 2. One or more objects O _i send an omnidirectional signal S of duration at least T. When sending S by several objects, these signals are superimposed, forming a common signal S of at least duration. When the signal S ends, the objects go to step 3. Further, the moment of the end of the signal S will be denoted as S ^* .

Step 3

The object O ₀ , upon receipt of S ^* sends to the object MS, to which the distance is determined, a signal S _{0ms of} duration ^* T. The signal will reach the MS no later than the time interval T. In response, the MS will send a signal ^* S _0ms , which will also reach O ₀ no later than the interval time T. In the time interval 2T+ ^* T after the object receives the signal S ^* , all the given signals will leave the communication channel.

The next object O ₁ waits for the arrival of the signal S _0ms and with a delay of 2T+ ^* T sends a signal S _1ms of duration ^* T to the MS object. Since by the moment the signal S _ims is sent, all the signals initiated by the object O ₀ will disappear, they will not interfere with the object Ο _i . The following objects O _i act similarly.

Thus, each object O _i with i≥1 adds a delay τ=i(2T+ ^* T) to the moment of occurrence of S _ims , initiating the transmission of signals by objects. The objects measure the time interval T _ims between the start of sending the signal S _ims and the start of receiving the signal ^* S _ims returned by the MS object. In this case, taking into account the speed of signal transfer also allows you to determine the distance from the object O _i to the object MS.

Thus, any object O _i gets the opportunity to measure the temporal and spatial remoteness of the object MS.

Step 4 is executed at the same time as step 3.

Step 4. Process SP ₀ . is executed once, terminated by a command from the application or after servicing all objects that started the process.

On the synchronous version of step 3. Above, the initiator of actions Ο ₁ is its detection of the event S ^* , the rest of the objects expect the signal S _ims to appear from the predecessor. But at step 3, all objects can switch to the mode of sequential determination of distances, reacting only to the appearance of S ^* . This option is focused on the worst mutual arrangement of objects.

Comment to step 3. A synchronous version of step 3 is considered. Let us turn to figure 1, where the signals S _ims and ^* S _ims have equal duration ^* T.

In the figure, for each pair of objects O _i and MS, areas with a duration of 2T+ ^* Τ are allocated for the exchange of signals S _ms and ^* S _ms . Within each area, each object O _i is allocated zone C and object MS is allocated zone ^* C with durations T, within which the signals S _ms and ^* S _ms reach the destination.

All objects of the group About detect the moment of completion of the signal S (S ^* in figure 1). Object O ₀ at this moment begins to transmit a signal S _ms of ^{duration *} T. observation fields of objects. Only after that the object O ₁ will begin to carry out its measurement for the object MS without conflict. The following objects of group O will do the same.

Thus, the delay τ=i(2Τ+ ^* Т) is performed by each O _i , which ensures that distance measurements by objects are also conflict-free for synchronous step 3.

Expanding the possibilities of SP ₀ . Here are some extensions to SP ₀ that enhance the capabilities of SP ₀ .

1. Transfer to SP ₀ additional information. Often an object O _i needs not only to determine T _ims , but also to inform other objects of additional information. To do this, it is enough to increase the value of ^* T to an arbitrary, common duration for all objects and transmit a message within ^* T.

The interval ^* T can also be different for different O _i , which the object must indicate at the beginning ^* T. Since objects O _i send non-directional signals, the duration ^* Τ will become known to all objects.

2. Renumbering of objects. Let's allow individual objects O _i not to participate in SP ₀ , i.e. do not transmit signal S _ims . If the object does not transmit S _ims , then we require that the objects following in order i still take into account the delays τ allocated to the "silent" objects. Since τ is known to the objects, the moment of appearance S ^* and the moments of appearance of signals S _ims are fixed, such accounting is simple. So, for example, if objects with i=0, … k are "silent", then the object with i=k+1 will get a new number i=0.

3. Determination of the number of participants SP ₀ . Process SP ₀ uses n - a predetermined number of participants in the process. Let's give it up. Let objects in SP ₀ be given only the maximum allowable number of "silent" objects arranged in a row. Exceeding this limit - a sign of reaching the last object in the group determines ^* n - the real maximum number of objects, members of SP ₀ .

SP timing correction process.

In SP ₀ the object O _i receives the result of measuring the distance to the object MS in a time interval not greater than τ=i(2T+ ^* T) after the start of the measurement. If there are n objects in the group, the object Ο _i+1 will start the next measurement in time nτ. This interval cannot be reduced. If the object requires a new reading, then the object performs it after the measurements taken by all objects O.

As shown in SP ₀ , this time interval can often be neglected. But when performing fast processes, for example, distributed computing operations, the time interval must be reduced. It will be reduced to 2L/s in SP due to frequent correction of T _ims , where L is the distance between the indicated objects, c is the speed of light. The SP correction is performed together with the group synchronization SP ₀ . During the execution of measurements for one object in SP ₀ , the SP process takes measurements for the entire group of objects.

Perform timing correction. In SP, the MS object will be an active object returning non-directional signals. Let's consider the general scheme of SP organization using SP ₀ . We assume that SP ₀ has been executed twice before the start of SP. After the first execution of SP ₀ , the objects, using ^* T messages, select an MS in a predetermined manner (see extension 1 in SP ₀ ). However, the MS may also be known in advance. After the second execution, T _max is known - the time of arrival of the signal to the MS from the object most distant from the MS and the times T _ims .

The SP process is allocated a separate channel in which the transmitted signals do not affect the signaling of SP ₀ . It is convenient to describe the process SP using the logical scale Q sent by the O _i objects to the MS. It consists of a sequence of binary digits, each of which is allocated to one of the objects O _i in accordance with its number i. Object O _i participates in scale transmission by sending a signal S _t in its scale position.

Correction begins with the actions of the object O ₀ upon receipt of the value T _0ms from SP ₀ . Object O ₀ sends a clock command (or signal) Sk to the MS. The MS object returns it to all O _i in the form ^* Sk by non-directional signals.

All objects O _i receive ^* Sk, and the object that managed to receive the value of the interval T _ims from SP ₀ sends a signal S _t to the MS in the corresponding digit of the Q scale. This is done in the following way.

The object sends the signal S _t with a standard delay for all O _i D=2(T _max -T _ims )+iT _ƒ , where T _ƒ is the time interval for transmitting the scale bit, the number of the scale bit i≥0. The duration T _ƒ is much less than T, which increases the accuracy of the correction.

Such actions place each signal S _t in the scale bit corresponding to the object O _i . Let's show it.

Let ^* Sk arrive at the object O _max , which is maximally remote from MS by the interval T _max . With a delay ^* D=2 (T _max -T _ims ), the signal from O _max will arrive at the MS in time 2T _max after sending ^* Sk by the MS object, since for O _max the delay is ^* D=0. But even for an arbitrary object O _i , its signal will arrive at the MS in time 2T _ims + ^* D=2T _max . The signals S _t of all objects arrive at the MS at the same time.

With a delay D, all objects will first receive a signal ^* S _t from the object O ₀ , then from Ο ₁ , etc., as required.

The transmission of the signal S _t by the object O _i is performed with a delay of 0.5T _ƒ , which places it in the center of the scale digit corresponding to the object O _i . The size of the scale bit (the duration of its transmission) is chosen so that the signal S _t sent to the middle of the scale bit does not leave the size of the scale bit when the interval T _{0ms changes} due to the movement of the object.

Objects O _i will receive from MS the entire scale ^* Q and in their scale position will receive a signal ^* S _t - a copy of the signal S _t sent to the MS. According to the shift in the discharge of the received signal, the objects correct their movement. During the time Τ correction is performed for all O _i .

On options for multiple sending of the Q scale. For multiple synchronization correction, the object ¹ 0 ₀ after the completion of receiving the scale ^* Q again sends the command Sk, and the correction process continues. At the cost of making objects more complex, correction can be somewhat accelerated. To do this, a Q _l scale is created, consisting of an arbitrarily large number of Q scales. Objects place signals in their bits of all Q scales.

Ways to complete the correction. Object ¹ O ₀ completes the correction on command from the application being executed by the system or in the absence of any signals in the network over a specified time interval. To complete the scale Q _l at the beginning of each scale Q included in Q _l , we add an additional control bit. Object ¹ O ₀ will add to it the completion command Q _l .

The correction process is completed.

After receiving T _0ms from the initial two-time execution of SP ₀ , the SP process receives from SP ₀ only the current values of T _ims . Otherwise, the SP process runs independently of SP ₀ . The correction eliminated the dependence of synchronization accuracy on the number of system objects that exists in SP ₀ .

The above run of SP ₀ twice before starting the SP is required on initial startup, and should only be repeated if there is a significant change in the object synchronization system. For example, when changing MS.

Detailed description of the proposed system. The proposed system of devices provides the technical implementation of the proposed method. The structure of the links of the system objects is shown in Fig.2.

The system consists of objects O _i of the group O _i ordered by 0≤i≤n, and an MS object, united by wireless non-directional transmission channels of optical or radio signals.

The MS device is capable of receiving signals S _ims , S _sp , S _t of devices O _i of group O and in response to the received signals to return to objects O _i signals ^* S _ims , ^* S _sp , ^* S _t different from the received signals.

Each object O _i contains a source U _{1 of} the signal S sent to other objects O _i and a receiver U _{2 of} this signal. Has an indicator U _{3 of} the completion of receiving the signal S. Has a source U _{4 of} the signal S _ims sent to the MS entity. Has a receiver U ₅ of the signal ^* S _ims , returned in O _i by the MS object, containing a timer Tm to count the time interval between sending the signal S _ims and receiving the signal ^* S _ims . Has a source U ₆ signal Ssp sent to the MS object, has a receiver U ₇ signal ^* S _sp returned in O _i by the MS object. Has a source U ₈ signal ^* S _t sent to the MS object, has a receiver U ₉ signal ^* S _t returned to U ₇ by the MS object. To control the interaction of the object O _i with other objects of the group O _i with the object MS and with a specific external device C, the object O _i has a control unit U ₁₀ connected to the inputs from U ₁₀ to the blocks U ₁ , U ₄ , U ₆ , U ₈ , connected to the outputs of the blocks U ₂ , U ₃ , U ₅ , U ₇ , U ₉ . Block U ₁₀ contains node C ₁₁ for signal exchange with external device C.

The MS device contains receivers U ₁₁ , U ₁₃ , U ₁₅ wireless signals, and their inputs receive signals from the outputs of signal sources U ₄ , U ₆ , U ₈ , respectively, and also contains sources U ₁₂ , U ₁₄ , U ₁₆ sending wireless signals respectively, in the signal receivers U ₅ , U ₇ , U ₉ .

Claims (3)

1. A method for decentralized autonomous synchronization of the interaction of digital mobile objects, characterized in that in a group of objects O _i ordered by 0≤i≤n and an MS object, in the absence of signal reception within a given time interval, the objects send a signal S of a fixed duration T to the MS, not less than the time interval of signal propagation between any objects O _i and MS, and, at the moment of termination of reception of the signal S, the object O ₀ sends to the MS object a signal or message S _{0ms of} duration ^* T, and each other object O _i , upon receipt from the object O _i-1 signal S _(i-1)ms like S _0ms also sprinkles like S _0ms signal S _ims with a delay τ=i(2T+ ^* T) and all objects measure the time interval T _ims between the start of sending S _ims and the start of receiving the signal or message returned from the MS ^* S _ims , while the object O ₀ , having received the value T _0ms , sends a signal or command Sk to the MS, which the MS returns as ^* Sk to all O _i , and O _i , having the value ing T _ims , send to MS within the interval T _ƒ signal S _t with delay D=2(T _max -T _ims )+iT _ƒ , receive from MS signal ^* S _t - a copy of the signal S _t and by the time interval between receiving ^* S _t and S _t correct their movement. 2. The method of decentralized autonomous synchronization of the interaction of digital mobile objects according to claim 1, characterized in that if the object O _i does not transmit S _ims , then the objects following in order after O _i allocate a delay τ to the object O _i and reduce their sequence number i by one , and if at the same time the maximum allowable group of consecutive non-signaling S _ims objects O _i is specified, then the sequence number of the object O _n immediately preceding this group is equal to the number of signaling S _ims objects of the group. 3. A system for decentralized autonomous synchronization of the interaction of digital mobile objects, characterized in that the system consists of a group O of objects O _i ordered by 0≤i≤n and an MS object combined with it by wireless communication channels, and each object O _i has a source U _{1 of} the sent objects O to receivers U _{2 of} the wireless signal S, has an indicator U _{3 of} the completion of signal reception S, has sources U ₄ , U ₆ , U ₈ sent to the object MS receivers U ₁₁ , U ₁₃ , U ₁₅ , respectively, signals S _ims , S _sp , S _t , where S _sp is the synchronization correction signal, has receivers U ₅ , U ₇ , U ₉ sent by sources U ₁₂ , U ₁₄ , U ₁₆ of the MS object, respectively, signals ^* S _ims , ^* S _sp , ^* S _t , has a block control U ₁₀ connected by communication lines with blocks U ₁ -U ₉ and with an external device With, organizing through U ₆ communication between O and MS.

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