JP2015151003A - Inverted-pendulum mobile body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce error between sensor values of respective sensors, and continue stable inversion control.SOLUTION: An inverted pendulum mobile body comprises: three or more sensors for outputting detection signals of a same detection object, respectively; control means for performing inversion control, based on the sensor value which is a central value when the respective sensor values output from the respective sensors are arranged in a descending order or ascending order; determination means for determining whether absolute values of the respective sensor values output by the respective sensors are equal to or less than a threshold, or not, in a start-up time or a stop state of the inverted pendulum mobile body; average calculation means for calculating an average value of differences between the sensor central value in the start-up time or the stop state, and the sensor values of the respective sensors, when the absolute values of the sensor values of the respective sensors are equal to or less than the threshold, by determination of the determination means; and correction means for correcting the sensor values of the respective sensors by subtracting or adding the average value of differences calculated by the average calculation means from the sensor values of the respective sensors.

Description

  The present invention relates to an inverted moving body that travels while maintaining an inverted state.

  An inverted moving body that detects a failure of each sensor by comparing sensor values output from a plurality of mounted same sensors is known (for example, Patent Document 1).

JP 2012-068189 A

For example, when detecting a sensor failure, the inverted moving body performs a return process to a normal sensor. At this time, if there is a large error between the sensor value of the fault sensor used for the inversion control and the sensor value of the normal sensor used in the return process, the inversion control becomes unstable when the sensor value is switched. There is a risk of becoming.
The present invention has been made in view of such problems, and a main object of the present invention is to provide an inverted moving body that can reduce an error between sensor values of each sensor and can continue stable inversion control. .

  One aspect of the present invention for achieving the above object is that when three or more sensors that output detection signals of the same detection target and sensor values output from the sensors are arranged in descending or ascending order, An inverted moving body comprising a control means for performing an inverted control based on a sensor value positioned at a position of the sensor value output from each sensor when the inverted moving body is activated or stopped. A determination means for determining whether or not the absolute value is less than or equal to a threshold; and when the determination means determines that the absolute value of the sensor value of each sensor is less than or equal to the threshold, the sensor center in the start-up or stop state An average calculating means for calculating an average value of the difference between the value and the sensor value of each sensor, and subtracting or adding the average value of the difference calculated by the average calculating means from the sensor value of each sensor. And a correcting means for correcting the sensor value of the sensors, it is inverted vehicle according to claim.

  ADVANTAGE OF THE INVENTION According to this invention, the inverted type mobile body which can reduce the error between the sensor values of each sensor and can continue stable inversion control can be provided.

FIG. 3 is a perspective view illustrating a schematic configuration of the inverted moving body according to the first embodiment. 1 is a block diagram showing a schematic system configuration of an inverted moving body according to Embodiment 1. FIG. 3 is a flowchart showing a control processing flow in the method for controlling an inverted moving body according to the first embodiment. FIG. 6 is a block diagram illustrating a configuration of a control system for an inverted moving body according to a second embodiment.

Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing a schematic configuration of an inverted moving body according to Embodiment 1 of the present invention. An inverted mobile body 1 according to Embodiment 1 of the present invention is operable on a vehicle main body 2 on which a passenger rides, a pair of left and right wheels 3 rotatably connected to the vehicle main body 2, and the vehicle main body 2. And an operation handle 4 provided. The inverted moving body 1 is configured as an inverted two-wheeled vehicle that can travel forward and backward, turn left and right, and accelerate and decelerate according to the movement of the center of gravity of the passenger while maintaining the inverted state.

  FIG. 2 is a block diagram showing a schematic system configuration of the inverted moving body according to the first embodiment of the present invention. The inverted moving body 1 according to the first embodiment includes a pair of wheel drive units 5 that drive each wheel 3, first to third sensors 6 that output detection signals of the same detection target, and each wheel drive unit. And a control device 7 for controlling 5.

  Each wheel drive unit 5 drives each wheel 3 based on a control signal output from the control device 7. Each wheel drive unit 5 includes, for example, a motor and a reduction gear connected to a rotation shaft of the motor so as to transmit power.

  The first to third sensors 6 are, for example, gyro sensors that detect around the same axis and have redundancy. For example, the first to third sensors 6 are provided in the vehicle body 2 and detect angular velocities in the pitch direction, the roll direction, and the yaw direction of the vehicle body 2. The first to third sensors 6 output the detected sensor values to the control device 7.

  The control device 7 calculates the attitude of the vehicle body 2 based on the sensor values output from the first to third sensors 6. The control device 7 calculates a torque command value for each wheel drive unit 5 in order to maintain the inverted state based on the calculated attitude of the vehicle body 2. The control device 7 performs an inversion control for maintaining the inversion state by outputting a control signal corresponding to the calculated torque command value to each wheel drive unit 5.

  The control device 7 temporarily stores, for example, a CPU (Central Processing Unit) that performs control processing, arithmetic processing, and the like, a ROM (Read Only Memory) that stores a control program executed by the CPU, an arithmetic program, processing data, etc. The hardware configuration is centered on a microcomputer comprising a RAM (Random Access Memory), etc. stored in the memory.

  By the way, conventionally, when an inverted moving body detects any sensor failure (for example, high level and low level sticking of the sensor value, offset, oscillation, etc.), return processing to a normal sensor (switching process) )I do. In general, there is an error between the sensor values of each sensor. Therefore, if there is a large error between the sensor value of the faulty sensor used for the inversion control and the sensor value of the normal sensor used for the return process, the sensor value changes greatly when the sensor value is switched. Inverting control may become unstable.

  On the other hand, the control device 7 according to the first embodiment averages the difference between the sensor median value at the center and the sensor value of each sensor 6 when the sensor values of each sensor 6 are arranged in descending or ascending order. By calculating the value and subtracting the average value of the difference from the sensor value of each sensor 6, the error of the sensor value of each sensor 6 is corrected. And the control apparatus 7 performs inversion control based on the sensor median value located in the center when the sensor values of the corrected sensors 6 are arranged in descending order or ascending order. Thereby, the error between the sensor values of each sensor 6 can be reduced, and stable inversion control can be continued.

  The control device 7 according to the first embodiment includes an inversion control unit 71 that performs inversion control, a sensor determination unit 72 that determines a sensor value, an average calculation unit 73 that calculates an average value of sensor values, and a sensor value. And a correction unit 74 for correction.

  The inversion control unit 71 is a specific example of the control unit, and is located in the center when the sensor values output from three or more sensors that output the detection signals of the same detection target are arranged in descending or ascending order. Inversion control is performed based on a sensor value (hereinafter referred to as a central sensor value). By performing the inversion control based on the central sensor value located in the center that is always normal, it is possible to perform the inversion control with higher reliability.

  The sensor determination unit 72 is a specific example of determination means, and determines whether or not the absolute value of the sensor value output from each sensor 6 when the inverted moving body 1 is activated is equal to or less than a threshold value. If the sensor value of each sensor 6 is abnormally large or small, an initialization error occurs when the inverted mobile body 1 is started. For example, when the vehicle main body 2 or the operation handle 4 of the inverted mobile body 1 is greatly inclined at the time of activation, an initialization error occurs when the vehicle main body 2 or the operation handle 4 is shaken and swings greatly.

  The sensor determination unit 72 determines that the sensor value (initialization process) of each sensor 6 is normal when the absolute value of the sensor value output from each sensor 6 is equal to or less than the threshold value. The sensor determination unit 72 outputs a signal (hereinafter referred to as a normal signal) indicating that the sensor value of each sensor 6 is normal to the average calculation unit 73.

  On the other hand, when the absolute value of the sensor value output from each sensor 6 is larger than the threshold value, the sensor determination unit 72 determines that the sensor value (initialization process) of each sensor 6 is abnormal. For example, the sensor determination unit 72 warns the user that the sensor value of each sensor 6 is abnormal (failure of the initialization process). For example, the sensor determination unit 72 gives a warning to the user to restart as an initialization error.

  The sensor determination unit 72 may determine whether or not the absolute value of the sensor value output from each sensor 6 when the inverted mobile body 1 is stopped is equal to or less than a threshold value. The stop state of the inverted mobile body 1 is a state in which the moving speed of the inverted mobile body 1 is substantially zero, and the state in which the inclination angle and the inclination angular velocity of the vehicle body 2 are substantially equal to each other from the traveling state. It shall include a stop state that stops at any time.

  The average calculation unit 73 is a specific example of an average calculation unit, and when the sensor values of the sensors 6 in the start-up or stop state are arranged in descending or ascending order according to the normal signal output from the sensor determination unit 72 The sensor median located in the center is extracted.

  Here, when the number of sensors is an odd number, the average calculation unit 73 can extract the central sensor value as it is. On the other hand, when the number of sensors is an even number, there are two central sensor values. For example, when the number of sensors is four, the central sensor value is the second and third sensor values in descending order or ascending order. For this reason, the average calculation unit 73 extracts one of the two central sensor values (a sensor value having a higher or lower order set in advance) or the average value of the two sensor values as the central sensor value.

  The average calculation unit 73 calculates an average value of the difference between the sensor median value and the sensor value of each sensor 6. The average calculation unit 73 outputs the average value of the calculated differences to the correction unit 74. The average calculation unit 73 calculates the average value of the difference between the sensor median value and the sensor values of all the sensors 6. However, the present invention is not limited to this, and the sensor median value and the preset representative sensors 6 are not limited thereto. You may calculate the average value of the difference with a sensor value.

  The correction unit 74 is a specific example of a correction unit, and subtracts or adds the average value of the difference calculated by the average calculation unit 73 from the sensor value of each sensor 6 to thereby obtain the sensor value of each sensor 6. to correct. Thereby, the error which exists between the sensor values of each sensor is reduced.

Thus, the process is simplified because the sensor value of each sensor 6 is corrected using only the sensor value of the same type of sensor. In addition, each sensor 6 is a redundant sensor and the output change of each sensor 6 is similar, so that a strict reference point for correction is not necessary. This eliminates the need for a horizontal detection process or the like when performing correction, thereby simplifying the process.
Further, by performing error correction based on the central sensor value located in the center that is always normal, error correction with higher reliability can be performed. Furthermore, in general, the sensor value error of a sensor depends on temperature. On the other hand, since the range in which the inverted mobile body 1 can travel with a single charge is limited, the temperature environment around it does not change significantly. Therefore, the sensor value of each sensor 6 can be stably corrected using the central sensor value at the time of starting or stopping.

The correction unit 74 outputs the corrected sensor value of each sensor 6 to the inversion control unit 71.
The inversion control unit 71 is located at the center when the sensor values of the sensors 6 corrected by the correction unit 74 are arranged in descending or ascending order, or is the average value of the sensor values of the sensors 6. Based on the inverted control.

For example, the sensor determination unit 72 determines whether or not the absolute values of the first to third angular velocities V1 to V3 output from the first to third gyro sensors 6 are equal to or less than a threshold Th (| V1 to V3 | ≦ Th). Determine.
The sensor determination unit 72 outputs a normal signal to the average calculation unit 73 when the absolute values of the first to third angular velocities V1 to V3 output from the first to third gyro sensors 6 are equal to or less than a threshold value.

  The average calculation unit 73 descends the first to third angular velocities V1 to V3 output from the first to third gyro sensors 6 in the start-up or stop state according to the normal signal output from the sensor determination unit 72 in descending order ( For example, the second angular velocity V2 located in the center when V1> V2> V3) is arranged is extracted as the central sensor value. The average calculation unit 73 calculates average values X1 to X3 of differences between the sensor median value V2 and the first to third angular velocities V1 to V3 of the first to third gyro sensors 6, and calculates the calculated average values X1 to X3. X3 is output to the correction unit 74.

  For example, the correction unit 74 subtracts the average value X of the differences from the first to third angular velocities V1 to V3 of the first to third gyro sensors 6 and corrects the first to third gyro sensors 6 of the first to third gyro sensors 6 corrected. The third angular velocities Va1 to Va3 are calculated.

  The inversion control unit 71 is positioned at the center when the first to third angular velocities Va1 to Va3 of the first to third gyro sensors 6 corrected by the correction unit 74 are arranged in descending order (for example, Va1> Va2> Va3). The second angular velocity Va2 to be extracted is extracted. The inversion control unit 71 executes the inversion control based on the extracted second central angular velocity Va2.

  In the above embodiment, a gyro sensor is applied as a sensor, but the present invention is not limited to this. As the sensor, for example, an angle sensor, an acceleration sensor, a rotation sensor, a magnetic sensor (orientation sensor), or the like may be applied, and the sensor can be applied to any sensor mounted on the inverted moving body 1. Moreover, in the said embodiment, although the structure using three gyro sensors is applied, it is not restricted to this. The present invention can also be applied to a configuration using four or more sensors that output detection signals of the same detection target.

  FIG. 3 is a flowchart showing a control processing flow in the control method of the inverted moving body according to the first embodiment. Note that the control processing shown in FIG. 3 is repeatedly executed every predetermined minute time.

The power source of the inverted mobile body 1 is turned on and the inverted mobile body 1 is activated (step S101). When the inverted moving body 1 is activated, each sensor 6 outputs the detected sensor value to the sensor determination unit 72 of the control device 7 (step S102).
The sensor determination unit 72 determines whether or not the absolute value of the sensor value output from each sensor 6 when the inverted mobile body 1 is activated is equal to or less than a threshold value (step S103).

  The sensor determination unit 72 determines that the sensor value of each sensor 6 is normal when the absolute value of the sensor value output from each sensor 6 is equal to or less than the threshold value (YES in step S103), and averages the normal signals. To the unit 73.

  In accordance with the normal signal output from the sensor determination unit 72, the average calculation unit 73 extracts the sensor median value located at the center when the sensor values of the sensors 6 at the time of activation are arranged in descending or ascending order (step) S104). Then, the average calculation unit 73 calculates an average value of the difference between the sensor median value and the sensor value of each sensor 6 (step S105), and outputs the calculated average value of the difference to the correction unit 74.

The correction unit 74 corrects the sensor value of each sensor 6 by subtracting the average value of the difference calculated by the average calculation unit 73 from the sensor value of each sensor 6 (step S106), and each corrected sensor 6 sensor value is output to the inversion control unit 71.
The inversion control unit 71 performs the inversion control based on the sensor median value located at the center when the sensor values of the sensors 6 corrected by the correction unit 74 are arranged in descending or ascending order (step S107).

  When the absolute value of the sensor value output from each sensor 6 is larger than the threshold value (NO in step S103), the sensor determination unit 72 determines that the sensor value of each sensor 6 is abnormal (step S108). The sensor determination unit 72 warns the user that the sensor value of each sensor 6 is abnormal (step S109).

  As described above, in the inverted moving body 1 according to the first embodiment, when the sensor values of the sensors 6 are arranged in descending order or ascending order, the average difference between the sensor median value located in the center and the sensor values of the sensors 6 The value is calculated, and the sensor value of each sensor 6 is corrected based on the calculated average value of the differences. Thereby, the error between the sensor values of each sensor 6 can be reduced, and stable inversion control can be continued.

Embodiment 2
Although the inverted mobile body 1 according to the first embodiment is configured as a single control system, the inverted mobile body 1 according to the second embodiment is configured as a dual control system. It is characterized by that. FIG. 4 is a block diagram showing a control system configuration of the inverted moving body according to the second embodiment. The inverted mobile body 1 according to the second embodiment is configured as a dual system for the purpose of improving reliability, and includes first and second systems 10 and 20. Thus, communication, control, and power supply for transmitting sensor information and control signals can be separated in each system, so that control can be continued in the other normal system even if an abnormality occurs in one system.

  The first system 10 includes a first control device 7 that controls each wheel drive unit 5, and first and second gyro sensors 6. The second system 20 includes a second control device 7 and a third gyro sensor 6.

  The first and second control devices 7 perform CAN communication and the like and perform data transmission / reception such as sensor information. The 1st and 2nd control apparatus 7 performs the inversion control based on the center sensor value similar to the control apparatus 7 which concerns on the said Embodiment 1 independently.

  The first control device 7 receives the angular velocities output from the first and second gyro sensors 6 of the own system system and the third gyro sensor 6 transmitted from the second control device 7 of the other system system at the time of system startup. It is determined whether the absolute value of the angular velocity is equal to or less than a threshold value.

  When the first control device 7 determines that the angular velocities of the first to third gyro sensors 6 are equal to or less than the threshold value, the first control device 7 is positioned at the center when the angular velocities of the first to third gyro sensors 6 are arranged in descending order or ascending order. The median value of the sensor to be extracted is extracted. Then, the first control device 7 calculates an average value of the difference between the sensor median value and the angular velocities of the first to third gyro sensors 6.

  The first control device 7 corrects the angular velocities of the first to third gyro sensors 6 by subtracting the calculated average values of the differences from the angular velocities of the first to third gyro sensors 6, respectively. The first control device 7 determines a torque command value for maintaining the inverted state based on the sensor median value located in the center when the corrected angular velocities of the first to third gyro sensors 6 are arranged in descending order or ascending order. calculate. The first control device 7 outputs a control signal corresponding to the calculated torque command value to each wheel drive unit 5.

  At the same time, when the system is activated, the second control device 7 outputs the angular velocity output from the third gyro sensor 6 of its own system and the first and second gyro sensors transmitted from the first control device 7 of the other system system. 6 determines whether the absolute value of the angular velocity output from 6 is equal to or less than a threshold value.

  When the second control device 7 determines that the angular velocities of the first to third gyro sensors 6 are equal to or lower than the threshold value, the second control device 7 is positioned at the center when the angular velocities of the first to third gyro sensors 6 are arranged in descending order or ascending order. The median value of the sensor to be extracted is extracted. Then, the second control device 7 calculates an average value of the difference between the sensor median value and the angular velocities of the first to third gyro sensors 6.

The second control device 7 corrects the angular velocities of the first to third gyro sensors 6 by subtracting the calculated average values of the differences from the angular velocities of the first to third gyro sensors 6, respectively. The second control device 7 calculates a torque command value for maintaining the inverted state based on the median value of the sensor located in the center when the corrected angular velocities of the first to third gyro sensors 6 are arranged in descending or ascending order. calculate. The second control device 7 outputs a control signal corresponding to the calculated torque command value to each wheel drive unit 5.
Each wheel drive unit 5 combines the control signals output from the first and second control devices 7 and drives each wheel 3 according to the combined control signal.

  According to the autonomous mobile body 1 according to the second embodiment, when the angular velocities of the respective gyro sensors 6 are arranged in descending or ascending order, the average value of the differences between the central sensor value and the angular velocities of the respective gyro sensors 6 And the angular velocity of each gyro sensor 6 is corrected based on the calculated average value of the differences. Thereby, the error between the sensor values of each gyro sensor 6 is reduced, and stable inversion control can be continued. Furthermore, since it is configured as a dual system, even if any one of the first and second systems 10 and 20 is abnormal, the inverted control can be continued stably. For this reason, the reliability of the inverted control can be greatly improved.

  In the second embodiment, since the other configuration is the same as that of the first embodiment, the same reference numerals are given to the same parts, and detailed description is omitted.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

  In the present invention, for example, the processing shown in FIG. 3 can be realized by causing a CPU to execute a computer program.

  The program may be stored using various types of non-transitory computer readable media and supplied to a computer. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer readable media are magnetic recording media (eg flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg magneto-optical disks), CD-ROM, CD-R, CD-R / W. Semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, and RAM are included.

  The program may also be supplied to the computer by various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

    DESCRIPTION OF SYMBOLS 1 Inverted type mobile body, 2 Vehicle main body, 3 Wheel, 4 Operation handle, 5 Wheel drive unit, 6 1st thru | or 3rd gyro sensor, 7 Control apparatus, 71 Inverted control part, 72 Sensor determination part, 73 Average calculation part, 74 Correction part

Claims (1)

Three or more sensors that output detection signals of the same detection target;
A control means for performing an inverted control based on a sensor value located in the center when the sensor values output from the sensors are arranged in descending order or ascending order,
Determination means for determining whether or not the absolute value of each sensor value output from each sensor in the startup or stop state of the inverted moving body is equal to or less than a threshold;
When the determination means determines that the absolute value of the sensor value of each sensor is equal to or less than the threshold value, the average value of the difference between the sensor median value at the start or stop state and the sensor value of each sensor is calculated. An average calculating means;
A correction means for correcting the sensor value of each sensor by subtracting or adding the average value of the difference calculated by the average calculation means from the sensor value of each sensor. Type moving body.

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