RU2708796C2 - METHOD OF COLLECTING TELEMETRIC INFORMATION ON THE STATE OF SPACECRAFT OBJECTS DURING TRANSPORTATION USING A WIRELESS SENSOR NETWORK ZigBee - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: invention relates to instrumentation using wireless sensor networks. Each autonomous sensor forms a terminal wireless sensor device (TWSD) consisting of a computing receiving-transmitting module, a detector (sensor), an interface unit and a power supply module. ZigBee protocol enables TWSD itself to be organized into distributed networks, to communicate with each other and to transmit a data packet with the result of measurements from the end device via a radio link between the nearest TWSD along the chain, from one TWSD to the other one, until it reaches the terminal point of the route.

EFFECT: use of a self-organizing wireless sensory network based on a ZigBee data transmission protocol together with sensors which monitor different physical parameters and values affecting transportable objects of the spacecraft during transportation.

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Description

The invention relates to instrumentation using wireless sensor networks and can be used to determine, collect and transmit data on the values of external factors to various objects that require certain conditions during transportation, for example, equipment, materials, objects of rocket and space technology (RKT).

This method of collecting and transmitting telemetric data using wireless sensors is designed to solve the following problems:

- identification and localization of emergency (emergency) situations (when they occur) in real time;

- documenting data on emergencies, including for making claims in case of violation of the conditions and rules of transportation, as well as evidence in case of insurance cases.

The invention is known "Method of operating a wireless sensor network and sensor node" [patent of the Russian Federation for the invention RU 2452036 C1, published on 05.27.2012], which describes the principle of formation of wireless sensor networks, their structure and functioning. The technical result of this invention is the ability to selectively configure the sensor node when other sensor nodes are within the radio range. This invention provides a general understanding of the construction of wireless sensor networks and the possibility of their application in various fields of life.

The invention is known "The complex of collection and analysis of telemetric information for monitoring the safety of objects" [patent of the Russian Federation for the invention RU 2337391 C1, published October 27, 2008], in which the control of high-rise structures and structures subjected to periodic or constant loading by removing telemetric data from sensors installed on various designs of the object of observation, each of which has a wired connection with blocks of decoding, analog-to-digital conversion of signals into mat for further processing, with transmit-receive units and storage devices. The disadvantages of this complex are the difficulty in setting up and preparing the installation, cumbersomeness, low flexibility and scalability, the presence of only wired sensors, the lack of self-organization in the telemetry information transmission system.

The invention is known "Wireless system of technical parameters of industrial facilities and its implementation" [patent of the Russian Federation for the invention RU 2430399 C1, published January 11, 2010], which implements the collection of telemetry information from sensors using a wireless sensor network based on the use of basic stations, routers and sensor modules. The information goes along a pre-planned route from the sensor module through a specific router to the base station. This system is claimed for use in studies of gas wells. The disadvantage of this system is the use of predefined telemetry routes from the sensor module to the base station, i.e. in the absence of communication between the router and the sensor modules attached to it, data will not be received at the base station. In addition, it is stated that the sensor module consists of a separate computing and transmitting device, therefore, the consumption of autonomous power is doubled. This system uses only pressure and temperature sensors.

The closest technical solution is an automated system for monitoring the transportation of goods by rail [patent of the Russian Federation for the invention RU 2466460 C2, published on 10.11.2012], designed to implement measures for the timely forecasting, detection and prevention of threats taking into account the data of automatic collection, processing and analysis of incoming information from vehicles (TS) carrying out the transportation of goods. This automated monitoring system contains a set of sensor equipment for monitoring the status of the transported cargo, information from which is transmitted to the central monitoring point (CPM) together with the current coordinates of the vehicle, while the sensor equipment can be distributed over several vehicles and connected to a single network or by wire or using the VHF radio channel, which is necessary when carrying out transportation by rail, in which the cargo is distributed among individual wagons that are part of a single train.

The main disadvantages of the known system are:

- the use of a wired communication type of some sensors, which eliminates the flexibility and complicates the deployment of the system at the object of observation;

- the use of VHF radio communication for transmitting information from sensors to the MSC, which is not an interference-protected communication channel, which may lead to the loss of telemetry data during transmission;

- lack of self-organization of the sensor system, i.e. the impossibility of transmitting the collected information of any of the sensors through adjacent sensors, bypassing the main data channel when it is inoperative.

The claimed method of collecting telemetric information about the state of the objects of the RKT using a wireless sensor network standard ZigBee (IEEE 802.15.4), allows you to eliminate the above disadvantages of the known system.

ZigBee is the only standardized wireless technology, initially aimed at monitoring and control of distributed sensor networks, as well as the deployment of wireless information networks for low-cost, low-power systems used in commercial, industrial and home automation.

The method for collecting and transmitting telemetric information about the state of RCT objects using the ZigBee protocol includes several classes of devices: a coordinator, which plays the role of a combined navigation and telecommunication module (hereinafter - KNTM), routers and terminal devices. The main task of KNTM is to set parameters and create a network, select the main radio frequency channel, and set a unique network identifier. At the same time, KNTM is the most complex of the three types of devices, it has the largest memory capacity and increased power consumption. Routers are used to expand the range of the network, since they are able to perform the functions of repeaters between devices located far from each other. In practice, most sensor network devices are terminal devices, and the use of routers and KNTM is necessary for the formation of communication bridges and the corresponding network topology. As soon as routers and other devices are connected to the network, they receive information about it from KNTM or any router already involved in the network, and based on this information set their operational parameters in accordance with the characteristics of the network. The router receives a table of network addresses, which it distributes between the terminal devices connected to the network. Thanks to the ZigBee protocol integrated into the computational modules, all operations for forming a network, connecting new devices, laying optimal message routes are carried out automatically, without the participation of an external microcontroller. This method of collecting and transmitting telemetric information allows the use of computing modules as independent nodes, in this case, the peripheral nodes available on the module — input / output ports, ADCs and DACs — and under the control of a single CSTM, which sends commands for each network device, act as a source of information .

The main advantages of this method are energy saving, increased autonomy and reliability, which is especially important for transmitting telemetric information from sensors, the volume of which rarely exceeds several tens of bytes. Most of the computing modules of the wireless sensor network operate according to the following algorithm: the device is in a “sleep” state almost all the time, providing an optimal energy-saving mode. When new information arrives, or during the next communication session, the device activates, quickly transmits data, and switches back to low power mode. Typical time delays in this case are 30 ms for connecting a new device to the network, 15 ms for switching from “sleeping” to active state, 15 ms for accessing the channel. The current consumption during transmission can be about 15 ... 30 mA, and in the "sleep" mode - less than 2 μA. Thus, it is possible to extend the life of the batteries by orders of magnitude, reduce their number and reduce the overall dimensions of the touch device.

Practical application of the claimed method of collecting telemetric information using a wireless sensor network to determine the status of the object of observation is achieved using the following technical means:

- Computing transceiver modules Zigbee;

- pressure sensors;

- humidity sensors;

- gas detector sensors;

- temperature sensors;

- accelerometers;

- smoke sensors;

- displacement sensors;

- interface units, each of which includes a ZigBee computing transceiver module, a sensor and together form a terminal wireless sensor device (OSSU);

- Li-ion batteries.

In FIG. 1 shows a diagram of the application of a method for collecting telemetric information using a ZigBee wireless sensor network:

1 ... 9 - OSSU (of various types, depending on the purpose of the sensor);

10 - combined navigation and telecommunications module;

11 - object of observation.

In FIG. 2 is a block diagram of terminal wireless sensor devices.

The measuring sensor 12 through the interface unit 13 is connected to the analog or digital inputs of the computing transceiver module ZigBee 14, depending on the type of sensor, to the elements of autonomous power supply 15. Autonomous power supply of the OSSA is carried out from lithium-ion batteries, the voltage and capacity of which are selected depending on sensor characteristics and the required product life. In OBSS, information is received from the measuring sensor, expressed in the appropriate units of measurement, conversion of the measured data into the format necessary for transmitting information over the wireless sensor network to the end point of the route - KNTM 10. In addition, each OBSS 1 ... 9 can act as a router , i.e. to be a connecting link (repeater) when transmitting telemetric data from neighboring sensors of OBSU 1 ... 9, if their connection with KNTM 10 is currently unavailable. This property allows you to build a self-organizing sensor network in which information loss is practically eliminated, since the transmission of information to the network 10 KNTM can be carried out through several chains that are currently available. KNTM 10 of the sensor network is responsible for building the OSSU 1 ... 9 network, organizing the optimal transmission routes for the telemetric data of each sensor, obtaining information from each sensor and storing it for subsequent processing, determining the navigation of an object using data from inertial and satellite navigation systems, processing received information and transmitting it via mobile cellular or satellite networks for final processing and storage.

The construction of the network OSSU 1 ... 9 is carried out as follows: KNTM 10 sends on the air at a certain frequency a polling signal in the form of its identifier and network number, OSSU 1 ... 9 located in the immediate vicinity of KNTM 10 and catching the polling signal, remember the identifier KNTM 10 and network number and send back their unique identifier (MAC address). If the interrogation signal from KNTM 10 does not reach the remote OSSUs, then these OBSUs, when turned on, send their signal on readiness to join the network by sending their unique identifier, so they can be connected to neighboring OSSUs that are part of the formed network, which automatically become routers (repeaters). The network of BSS 1 ... 9 is located directly on the controlled transported object 11.

The number of OBSS can easily be increased or decreased to the required value, according to the set tasks and conditions, which allows you to flexibly configure and scale the telemetric data acquisition system, for this, the newly connected OBSS needs only to scan the air for the presence of a CSTM or a neighboring OBSS already included in the network and Get approval from him for a network connection. This function allows you to deploy a telemetry collection network in the shortest possible time, in comparison with well-known analogues, on virtually any vehicle and monitor the status of any objects.

The technical result of the implementation (method) of the invention are:

- the possibility of flexible scaling and configuration of the sensor system by adding new devices or reducing existing ones;

- improving the reliability of data transmission due to the ability of network nodes to self-organize and use an interference-protected communication channel;

- the use of wireless proximity sensors with low power consumption;

- the ability to reduce energy consumption and increase autonomy by finding computing modules in a "sleeping" state most of the time;

- reducing the deployment time of the system through the use of wireless touch devices;

- the ability to use on any type of transport.

The ZigBee method of collecting telemetric information about the state of RCT objects using a wireless sensor network is one of the key elements of the hardware-software complex of a wireless system for assessing the state of various objects during their transportation.

Claims (2)

1. A method for collecting telemetric information about the state of objects of rocket and space technology (RKT) during transportation using a ZigBee wireless sensor network with wireless sensor devices (OSSU), consisting of ZigBee computing transceiver modules, sensors of various nature and measuring various physical quantities and processes connected to the analog or digital inputs of the ZigBee computing transceiver module, lithium-ion batteries, and the ZigBee computing modules interface units with sensors and lithium-ion batteries, characterized in that, using the built-in software of the ZigBee computing transceiver module, the OSSU can operate in the coordinator state, allowing the OSSU to send a polling radio signal with an identifier and network number to the air at a given frequency and build a self-organizing wireless sensor network from those located in the zone the coverage of the radio signal of other OSSUs, which, receiving the network identifier from the coordinator, send the return radio signal with their unique device identifier, connect being connected to the wireless sensor network and in the routing state to perform the function of sending telemetry information from other OSSUs that are outside of direct radio communication with the coordinator, to the coordinator or the state of a terminal device that performs the direct function of collecting measurements from a sensor or sensors connected to analog or digital inputs of the ZigBee compute transceiver module. 2. The method according to p. 1, characterized in that any OSSU located in the coverage area of the radio signals of the coordinator or OSSU in the routing state can connect to the wireless sensor network, being at a given frequency and supplying the request radio signal with its unique identifier and receiving back from the coordinator directly or through the OSSA in the routing state, the identifier and network number.

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