JP2018073207A - Detected data collection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sensor output at the same point in time in a detected data collection device, to transmit a plurality of sensor outputs in a single communication, and to have a single incorrect detection code for the plurality of sensor outputs with a detection data collection device while suppressing increase in the number of a signal line between a primary device and a plurality of sensors.SOLUTION: Detection data of all the sensors 111, 112, 121, 122, 131, 132 is simultaneously taken into communication units 113, 123, 133 at a chip select falling and a sensor output at the same point in time is obtained. An ECU102 and a plurality of sensors 103 to 105 subjected to daisy chain connection transmit and receive data to transmit a plurality of sensor outputs in a single communication. A latter most stage sensor 105 among the sensors 103 to 105 creates an incorrect code of data from the front stage sensors 103, 104 and the incorrect code of data of the sensor 105 itself to make it a single incorrect code. Since the sensor output at the same point in time of the plurality of sensors has been obtained by chip select falling, no signal line is required to be installed from the ECU102 to each of the sensors 103, 104, 105.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a detection data collection device that collects detection data from a plurality of sensors.

  As an example of the detection data collection device, there is a device that collects detection output from an inertial sensor. As this detection data collection device, devices as disclosed in Patent Documents 1 and 2 are disclosed, and a full-duplex communication method is used as a communication method.

  Patent Document 1 shows an example in which information for identifying a sensor is included in a command to share a chip select signal (communication start signal).

  Patent Document 2 discloses an example in which a plurality of sensors are connected in a daisy chain to reduce the number of signal lines, and each sensor is accessed on the communication path to acquire sensor data.

Japanese Patent No. 4917671 Japanese Patent Laid-Open No. 11-2111517

  For example, in a sensor that detects angular velocity, acceleration, etc. while the vehicle is running, a sensor that transmits from the sensor side to the main device side according to the purpose of use such as prevention of vehicle skidding and vehicle attitude control for assisting safe driving It is desirable that the type and number of data can be changed as appropriate.

  However, in the prior art, when the main device side receives a plurality of sensor outputs by communication, it usually receives a sensor output by accessing one sensor in a single communication. Can not receive. For this reason, since it is difficult to recognize the characteristics of the controlled object at the same time, it is difficult to improve the control accuracy.

  Further, in the conventional technology, it is necessary to receive an error detection code for each communication and perform an error detection process, so there is a problem that it takes time to obtain a plurality of sensor outputs, It was difficult to improve responsiveness.

  The present invention has been made in view of such circumstances, and the object of the present invention is to obtain a sensor output at the same time, transmit a plurality of sensor outputs in one communication, and a plurality of It is to realize a detection data collecting device capable of reducing an increase in the number of signal lines between the main device and a plurality of sensors, so that one error detection code for each sensor output is reduced.

  In order to achieve the above object, the present invention is configured as follows.

  In the detection data collection device, a plurality of sensors that detect physical quantities, a control unit that transmits a communication start signal and a command signal to the plurality of sensors, and collects data detected by the plurality of sensors; And a memory that stores data indicating physical quantities detected by the plurality of sensors when the plurality of sensors receive the communication start signal.

  Obtaining sensor outputs at the same time, transmitting multiple sensor outputs in one communication, and using one error detection code for multiple sensor outputs, the number of signal lines between the main device and multiple sensors It is possible to realize a possible detection data collection device while suppressing an increase in the above.

It is a block diagram at the time of applying the detection data collection device which is one Example of this invention to the inertial force detection apparatus of a vehicle. It is a figure which shows an example of the command transmitted to 6 axis | shaft sensor unit from ECU. It is a table | surface which shows an example of a sensor identification signal. It is a table | surface which shows an example of an output classification signal. It is a table | surface which shows an example of the signal which shows completion | finish of a command. It is a figure which shows an example of the response transmitted to ECU from the communication part of three sensors. It is a time chart which shows the communication operation | movement with ECU shown in FIG. 1, and a 6-axis sensor unit. It is a figure which shows an example of a communication part. It is a figure which shows an example of the internal circuit of the output data selection part shown in FIG. It is the figure which made the communication part shown in FIG. 8 the functional block.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a block diagram of a case where a detection data collection device according to an embodiment of the present invention is applied to a vehicle inertia force detection device (a device that detects inertial force (angular velocity, acceleration) as a physical quantity).

  In FIG. 1, a 6-axis sensor unit 101 detects an angular velocity (Yaw) of three axes (x, y, z axes) and an acceleration (G) of three axes. The six-axis sensor unit 101 includes a sensor A103, a sensor B104, and a sensor C105.

  The sensor A 103 is a communication unit 113 that transmits sensor data detected in accordance with an angular velocity (xYaw) detection element 111 in the x-axis direction, an acceleration (xG) detection element 112 in the x-axis direction, and a command (command signal) from an external device. It has.

  The sensor B104 and the sensor C105 have substantially the same configuration as the sensor A103, and the sensor B104 includes an angular velocity (yYaw) detection element 121 in the y-axis direction, an acceleration (yG) 122 in the y-axis direction, and a communication unit 123. . The sensor C105 includes an angular velocity (zYaw) 131 in the z-axis direction, an acceleration (zG) 132 in the z-axis direction, and a communication unit 133.

  The ECU (electronic control unit (control unit)) 102 transmits the requested sensor data type as a command (command signal) to the 6-axis sensor unit 101. The six-axis sensor unit 101 returns the requested sensor data as a response to the command from the ECU 102. As a signal line for communication, the ECU 102 and the three sensors 103, 104, 105 are connected in a daisy chain.

  Specifically, the command from the ECU 102 is transmitted to the receiving unit of the communication unit 113 of the sensor A103. The transmission unit of the communication unit 113 is connected to the reception unit of the communication unit 123 of the sensor B104. The transmission unit of the communication unit 123 is connected to the reception unit of the communication unit 133 of the sensor C105. And the transmission part of the communication part 133 of the sensor C105 of the last stage connected by the daisy chain connects to the response receiving part of ECU102.

  A clock (clock signal) output from the ECU 102 is a signal for synchronizing communication, and 1-bit data is transmitted and received in one clock. The chip select (communication start signal) is a signal indicating a period for performing one communication, and communication with the 6-axis sensor unit 101 is executed during a period in which the signal level is L (low). Since the clock signal line and the chip select signal line need to be input simultaneously to the three sensors A103, B104, and C105, the ECU 102 and the three sensors A103, B104, and C105 are directly connected.

  FIG. 2 is a diagram illustrating an example of a command transmitted from the ECU 102 to the 6-axis sensor unit 101. The command is transmitted through one signal line, and the data changes in synchronization with the falling edge of the clock. The communication units 113, 123, 133 of the 6-axis sensor unit 101 take in command data at the rising edge of the clock. There are three command contents: a sensor identification signal, an output type signal, and an EOC (end of command) indicating the end of the command.

  As shown in FIG. 2, the format of the signal to be transmitted is transmitted in the order of sensor identification 1, output type 1, sensor identification 2, output type 2, sensor identification 3, output type 3, and EOC in a continuous 4-bit set. . Here, for example, when only one sensor output is requested, EOC is transmitted after sensor identification 1 and output type 1.

  FIG. 3 is a table showing an example of the sensor identification signal. In FIG. 3, it is a signal indicating which of the three sensors 103, 014, and 105 is to request the data, with data of a combination of 2 bits.

  FIG. 4 is a table showing an example of the output type signal. In FIG. 4, it is a signal indicating which data is requested among the angular velocity, the acceleration, and the self-diagnosis result of the sensor as a sensor output in a combination of 2 bits.

  FIG. 5 is a table showing an example of a signal indicating the end of a command. In FIG. 5, EOC (end of command) is notified by transmitting 0 continuously for 4 bits.

  FIG. 6 is a diagram illustrating an example of responses transmitted from the communication units 113, 123, and 133 of the three sensors 103, 104, and 105 to the ECU 102. In FIG. 6, the response data changes in synchronism with the fall of the clock during the L level period from the fall of the chip select until the rise. The ECU 102 captures command data at the rising edge of the clock. The length of one reply data is 16 bits. The sensor C105 sends a maximum of five reply data from reply 1 to reply 5.

  FIG. 7 is a time chart showing a communication operation between the ECU 102 and the six-axis sensor unit 101 shown in FIG. In FIG. 7, a chip select, a clock, and a command are transmitted from the ECU 102 to the 6-axis sensor unit 101. In synchronism with the fall of the chip select, the three sensors 103, 104, and 105 receive the outputs from the angular velocity detection elements 111, 121, and 131 and the acceleration detection elements 112, 122, and 132, respectively, and the communication units 113, 123, and 133. To remember.

  In this way, all the outputs of the six sensors 103, 104, and 105 at the same time are stored. Note that the same point in time does not have to be exactly the same, but is a point in time that can be regarded as the same regarding the behavior of the vehicle or the like.

Next, commands sent from the ECU 102 are simultaneously input to the three communication units 113, 123, and 133 via the daisy chain connection of the three sensors 103, 104, and 105. When the input of the command is completed, each sensor 103, 104, 105 recognizes what output the reply data itself sends out. In this way, signals are transmitted to and received from the sensors 103, 104, 105 and the control unit 102 by the signal lines connected in a daisy chain. In the first communication example shown in FIG. The output of xYaw 111 of sensor A103, the second output of yYaw121 of sensor B104, and the third output of zYaw131 of sensor C105.

  Therefore, immediately after the 16-bit command input is completed, the output of xYaw 111 is transmitted from the communication unit 113 of the sensor A 103 to the ECU 102 through the communication unit 123 and the communication unit 133. At this time, the communication unit 133 of the sensor C105, which is the final stage of the daisy chain connection, performs the calculation of the CRC that is the error detection code of the communication to be sent out at the same time as the output of xYaw111.

  Next, the output of yYaw 121 from the communication unit 123 of the sensor B 104 passes through the inside of the communication unit 133 and is sent to the ECU 102 as second transmission data. At this time, the communication unit 133 of the sensor C105 performs CRC calculation, which is an error detection code to be transmitted last, simultaneously with the output of yYaw121.

  Next, the output of zYaw 131 is sent to the ECU 102 from the communication unit 133 of the sensor C105 as third sending data. At this time, in the communication unit 133 of the sensor C105, the CRC which is the error detection code to be transmitted last is performed simultaneously with the output of zYaw131.

  Thereafter, the communication unit 133 finally sends out CRC data obtained from the continuous outputs of xYaw111, yYaw121, and zYaw131 to complete the communication.

  In the second communication example, the content of the command first requests the output of zG132 of the sensor C105, and the second requests the output of xYaw111 of the sensor A103.

  Therefore, immediately after the 16-bit command input is completed, the output of zG132 is sent to the ECU 102 from the communication unit 133 of the sensor C105. At this time, CRC calculation is performed simultaneously with the output of zG132 in the communication unit 133 of the sensor C105.

  Next, the output of xYaw 111 from the communication unit 113 of the sensor A 103 passes through the communication unit 123 and the communication unit 133 and is sent to the ECU 102 as second transmission data. At this time, the communication unit 133 of the sensor C105 performs the calculation of the CRC that is the error detection code to be transmitted last, simultaneously with the output of xYaw111. Thereafter, the communication unit 133 finally transmits the CRC data obtained from the continuous outputs of zG132 and xYaw111 to complete the communication.

  Thereby, the ECU 102 collects detection data continuously output from the sensors 103, 104, and 105.

  FIG. 8 is a diagram illustrating an example of the communication unit 113. Note that the communication unit 123 and the communication unit 133 have the same configuration.

  In FIG. 8, an angular velocity storage unit 201 is a register that temporarily stores angular velocity data output from the angular velocity detection element (sensor element) 111, and stores angular velocity data in synchronization with the falling edge of the chip select signal.

  The acceleration storage unit 202 is a register that temporarily stores acceleration data output from the acceleration detection element (sensor element) 112. Acceleration data is stored in synchronization with the fall of the chip select signal. The switch 203 selects and outputs angular velocity data or acceleration data according to the inertia force selection signal of the output data selection unit 211. The parallel-serial conversion unit 204 converts 16-bit parallel data into 1-bit serial data for transmission to an external device.

  The switch 205 selects whether the input data for calculating the CRC that is the error detection code is the data of the self sensor or the data input from the previous stage, based on the self sensor selection signal of the output data selection unit 211.

  The CRC generation unit 206 sequentially performs CRC calculation on serial data input in synchronization with the clock and supplies the calculation result to the switch 207 that sequentially outputs the serial data as serial data.

  The switch 207 selects and outputs inertial force (angular velocity or acceleration) data or CRC data according to the CRC selection signal of the output data selection 211. The CRC output is selected by the switch 207 when the response signal is transmitted as the last data following the transmission of all sensor data requested from the ECU 102.

  The switch 208 selects the data (command or inertial force output of the previous sensor) input from the previous sensor or the output of the own sensor (inertial force output or CRC output) based on the own sensor selection signal of the output data selection unit 211. Output. The serial / parallel conversion unit 209 converts a command input as 1-bit serial data from the ECU 102 into 16-bit parallel data. The command receiving unit 210 is a register that temporarily stores the clock signal when 16 clocks are input after the fall of the chip select signal.

  The data is held in the command receiving unit 210 until the next communication command is input.

  The output data selection unit 211 controls switching of the switches 203, 205, 207, and 208. Details of the output data selection unit 211 will be described with reference to FIG.

  The counter 212 counts the number of clock inputs after the chip select falls. The output data selection unit 211 controls the switching timing of each switch based on the output of the counter 212. The sensor identifier storage unit 213 recognizes the position of itself among the three sensors. Data shown in FIG. 3 is stored in the communication units 113, 123, and 133 of the three sensors of the six-axis sensor unit 101 in FIG.

  Although the CRC creation unit 206 exists in the communication unit 113 shown in FIG. 8, the error detection code is not created in the communication unit 113, so the switch 207 is set on the parallel-serial conversion unit 204 side. The same applies to the communication unit 123.

  Therefore, the CRC generation unit 206 can be omitted in the communication units 113 and 123.

  FIG. 9 is a diagram illustrating an example of an internal circuit of the output data selection unit 211 illustrated in FIG. The comparison units (comparators) 301, 302, and 303 output “1” if the sensor identifications 1, 2, and 3 of the command reception unit 210 and the output of the sensor identifier storage unit 213 match, and must match. “0” is output.

  If the output of the comparison unit 301 is “1”, it indicates that the response is output to the response reply 2 shown in FIG. Similarly, if the output of the comparison unit 302 is “1”, the response 3 is output. If the output of the comparison 303 is “1”, the response 4 is output.

  The comparison unit 304 outputs “1” during the period from 17 to 32 when the output of the counter 212 that counts the clocks. The comparison unit 305 outputs “1” during the period when the output of the counter 212 is 33 to 48, and the comparison unit 306 outputs “1” when the output of the counter 212 is between 49 and 64. The comparison unit 307 outputs “1” during a period in which the output of the counter 212 is 65 to 80. These outputs indicate the output timing of the reply data 2 to 5 shown in FIG.

  The AND circuits 308 to 313 are logical products, and output “1” when both inputs are “1”. The period when the output is “1” indicates that the output of the own sensor is selected.

  The AND circuit 308 selects the output of its own sensor during the reply 2 period shown in FIG. 6, the AND circuit 309 selects the output of the own sensor during the reply 3 period, and the AND circuit 310 during the reply 4 period. The AND circuit 311 outputs “1” when the own sensor is selected during the reply 2 period and the acceleration is selected in the output type 1 of the command receiving unit 210. Similarly, the AND circuit 312 outputs “1” when acceleration is selected during the reply 3 period and the AND circuit 313 when acceleration is selected during the reply 4 period.

  The OR circuit 314 is a three-input logical sum, and outputs a self-sensor selection signal for three periods as one self-sensor selection signal. Similarly, the OR circuit 315 outputs acceleration selection signals for three periods as one acceleration selection signal. The constant output unit 316 outputs a continuous 4-bit “0”.

  The comparison unit 317 outputs “1” when the consecutive 4 bits of the sensor identification 1 and the output type 1 of the command reception unit 210 are “0”. When this output is "1", it indicates that an EOC (end of command) has been detected.

  Similarly, the comparison unit 318 indicates that the sensor identification 2 and the output type 2 are detected, the comparison unit 319 indicates that the sensor identification 3 and the output type 3 are detected, and the comparison unit 320 indicates that the sensor identification 4 and the output type 4 are detected.

  The AND circuits 321 to 324 are logical products, and output “1” when both inputs are “1”. The period when the output is “1” indicates that the CRC which is the error detection code is selected. The AND circuit 321 selects the CRC output during the reply 2 period shown in FIG. 6, the AND circuit 322 selects the CRC output during the reply 3 period, the AND circuit 323 selects the CRC 4 period, and the AND circuit 324 selects the CRC output during the reply 5 period. The OR circuit 325 is a 4-input OR, and outputs a CRC selection signal for four periods as one CRC selection signal.

  FIG. 10 is a functional block diagram of the communication unit 113 shown in FIG. As described above, the configuration of the communication unit 113 is the same as the configuration of the communication units 123 and 133.

  In FIG. 10, the communication unit 113 includes a memory 400, a chip select rising / falling determination unit (communication start determination unit) 401, a command determination unit (command determination unit) 402, a data transfer determination unit 403, and a CRC creation unit. (Error detection code creation unit) 404 and data output unit 405 are provided.

  When it is determined that the chip select has fallen, the chip select rising / falling determination unit 401 takes in the output data of the angular velocity sensor 111 and the acceleration sensor 112 and stores them in the memory 400. The command determination unit 402 determines an input command and reads data stored in the memory 400. Then, the command determination unit 402 sends the input command and the data extracted from the memory 400 to the data transfer determination unit 403.

  If there is data from the previous stage, the data transfer determination unit 403 receives the data, determines whether it is necessary to create a CRC that is an error detection code of data from the command determination unit 402 or data from the previous stage, If necessary, the CRC creation unit 404 is instructed to create a data error detection code.

  The data transfer determining unit 403 determines data to be transferred among the data from the command determining unit 402, the data from the previous stage, and the error detection code of the data generated by the CRC generating unit 404.

  The data determined to be transferred by the data transfer determination unit 403 is output to the data output unit 405, and the data output unit 405 transmits the output data to the next communication unit or transmits it to the ECU 102 as a response.

  As described above, according to one embodiment of the present invention, the detection data of all the sensors 111, 112, 121, 122, 131, and 132 are simultaneously transmitted to the communication units 113, 123 by the fall of the chip select (communication start signal). 133, and the sensor output at the same time is obtained.

  Further, according to one embodiment of the present invention, since the ECU 102 and the plurality of sensors 103, 104, 105 connected in a daisy chain perform data transmission / reception, a plurality of sensor outputs can be obtained in one communication. Can be sent.

  In addition, among the plurality of sensors 103, 104, and 105 connected in a daisy chain, the last-stage sensor 105 creates an error code for the data from the previous-stage sensors 103 and 104 and an error code for the data of the sensor 105 itself. Therefore, the created error code can be made into one error code, and the CRC process can be performed once, and the processing speed can be improved.

  Furthermore, according to one embodiment of the present invention, since the sensor outputs at the same time of a plurality of sensors are obtained by the fall of the chip select, signal lines are provided from the ECU 102 to the respective sensors 103, 104, 105. There is no need, and there is no increase in the number of signal lines between the ECU 102 as the main device and the sensors 103, 104, and 105.

  The above-described example is an example in which the present invention is applied to a vehicle inertial force detection device. However, the present invention is also applicable to a device that detects physical quantities other than inertial force such as temperature, humidity, and pressure. .

  The present invention is also applicable to a physical quantity detection device for an object that moves other than a vehicle.

  101 ... 6-axis sensor unit, 102 ... ECU, 103 ... sensor A, 104 ... sensor B, 105 ... sensor C, 111 ... x-axis angular velocity detection element, 112 ... x-axis acceleration detection element, 113, 123, 133 ... communication unit, 121 ... y-axis angular velocity detection element, 122 ... y-axis acceleration detection element, 131 ... z-axis angular velocity detection element, 132,. Z-axis acceleration detection element, 201 ... angular velocity storage unit, 202 ... acceleration storage unit, 203, 205, 207, 208 ... switch, 204 ... parallel-serial converter, 206 ... CRC generation , 205, switch, 209, serial / parallel converter, 210, command receiver, 211, output data selection unit, 212, counter, 213, sensor identification Storage unit, 301 to 307, 317 to 320... Comparator, 308 to 313, 321 to 324... AND circuit, 314, 315, 325... OR circuit, 316. Memory 401: Chip select rising / falling judgment unit 402 ... Command judgment unit 403 ... Data transfer judgment unit 405 ... Data output unit

Claims (8)

A plurality of sensors for detecting physical quantities;
A control unit for transmitting a communication start signal and a command signal to the plurality of sensors and collecting data detected by the plurality of sensors;
And a memory for storing data indicating physical quantities detected by the plurality of sensors when the plurality of sensors receive the communication start signal from the control unit. The detection data collection device according to claim 1,
Each of the plurality of sensors selects data corresponding to a command signal from the control unit from the data stored in the memory, and continuously outputs the selected data from the plurality of sensors. A detection data collection device characterized by being collected in a unit. In the detection data collection device according to claim 2,
At least one of the plurality of sensors has an error detection code generation unit that calculates and outputs a communication error detection code following data continuously output from the plurality of sensors. Detection data collection device. In the detection data collection device according to claim 3,
2. A detection data collecting apparatus, wherein the signal lines of the plurality of sensors are daisy chain connected, and signals are transmitted to and received from the control unit through the daisy chain connected signal lines. In the detection data collection device according to claim 4,
The sensor connected to the last stage of the plurality of sensors connected in the daisy chain calculates an error detection code of detection data of each of the plurality of sensors, and calculates the error detection calculated after data transmission to the control unit. A detection data collection device characterized by transmitting a code. In the detection data collection device according to claim 1 or 5,
Each of the plurality of sensors receives a sensor element for detecting a physical quantity, the memory for storing data indicating the physical quantity detected by the sensor element, and the data stored in the memory and a command signal from the control unit. A detection data collection device comprising: a communication unit for transmission. In the detection data collection device according to claim 6,
Each of the plurality of sensors is
In accordance with the communication start signal transmitted from the control unit, a communication start determination unit that stores data indicating a physical quantity detected by the sensor element in a memory;
A command determination unit that reads data indicating a physical quantity stored in the memory in accordance with a command signal transmitted from the control unit;
An error detection code creating unit for creating an error detection code of data indicating the physical quantity;
The data indicating the physical quantity read by the command determination unit, the data transmitted from the sensor in the previous stage, and whether or not to use the error detection code created by the error detection code creation unit, determine the data to be transferred A data transfer determination unit to output;
And a data output unit for outputting data output from the data transfer unit to the sensor or the control unit in the next stage. In the detection data collection device according to any one of claims 1 to 7,
The physical quantity detected by the plurality of sensors is an angular velocity and acceleration of a vehicle.

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