JP2009275814A - Vibration damping device and vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration damping device and a vehicle capable of continuing to keep a high damping effect even if vibration transmission characteristics from an excitation means up to a vibration detection means are changed in vibration damping object equipment. <P>SOLUTION: The vibration damping device includes: a vibration detection means 5, which detects vibration, at a position where the vibration should be damped, transmitted from a vibration generation source 1 to output it as a vibration signal; the excitation means 10, which is provided at a different position from the position where the vibration should be damped to generate a vibration damping force for canceling the vibration at the position where the vibration should be damped; an excitation command generation means 3, which outputs an excitation command for generating the vibration damping force to the excitation means 10 from the vibration signal and a reference wave having a frequency component of the frequency of the vibration generated by the excitation generation source 1; and a phase correction means 3, which corrects the phase of the excitation command by reverse characteristics of the vibration transmission characteristics from the excitation means 10 up to the vibration detection means 5 and a phase correction amount so as to make a phase difference between the vibration signal and the excitation command match a target phase angle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vibration damping device that suppresses generated vibration and a vehicle including the same.

2. Description of the Related Art Conventionally, there has been known a vibration damping device that counteracts vehicle vibrations by generating vibration damping force by a vibration means and actively exciting the vehicle vibrations caused by fluctuations in the output torque of the vehicle engine. More specifically, such a vibration damping device includes a linear actuator as a vibration means provided in an engine as a vibration generation source, a means for detecting the rotation speed of the engine as a vibration generation source, Proposed is provided with vibration detection means for detecting vibration at a position to be shaken and an adaptive control algorithm for outputting a vibration command to the linear actuator based on the detected engine speed and vibration at the position to be dampened (For example, refer to Patent Document 1). In this vibration damping device, it is possible to output a vibration command having an optimum amplitude and phase corresponding to the vibration currently detected at the position where the vibration is to be controlled by the adaptive control algorithm. The vibration generated from the engine that is the source of vibration due to the vibration control force generated by the vibration means can be reduced and transmitted to the position to be controlled such as the seat.

In addition, the vehicle's shaker, a characteristic map that stores the vibration transfer characteristics from the place where the shaker is installed to a predetermined point in the vehicle interior, and a signal detected by the acceleration sensor and the vibration transfer characteristic at a predetermined point in the vehicle interior. There is known an apparatus that includes a digital filter that predicts vibration and reduces vibration by applying vibration using a shaker so as to reduce the predicted vibration (see, for example, Patent Document 2).

  On the other hand, a linear actuator in which a movable element is supported by an elastic support portion (plate spring) so as to be able to reciprocate with respect to a stator is known as a vibrating means for performing reciprocating movement (for example, Patent Documents). 3). Since this linear actuator does not wear the mover, the accuracy of shaft support does not deteriorate even after long-term use. Also, since sliding resistance does not act on the mover, power loss due to sliding resistance is small. Furthermore, since the bulky coil and the elastic support portion can be arranged close to each other, the linear actuator can be miniaturized.

The linear actuator described in Patent Document 3 can cancel the vibration generated by the target device to be controlled by the reaction force during driving. That is, by applying a current command so that the reaction force generated by the actuator has an opposite phase with respect to the vibration acceleration of the vibration suppression target device, the actuator can reduce the vibration of the vibration suppression target device. In general, in order to increase the reaction force of the actuator, an auxiliary mass (weight) is given to the mover. By attaching a vibration damping device using such a linear actuator to the vehicle body, the force applied to the vehicle body from the engine of the vehicle can be offset, so that vibration of the vehicle body can be reduced.
JP-A-10-049204 Japanese Patent Application Laid-Open No. 08-226489 JP 2004-343964 A

  Incidentally, in the vibration damping device disclosed in Patent Document 1, a linear actuator that is a vibration means is mounted in the vicinity of an engine that is a vibration generation source of the vehicle body. For example, the linear actuator described in Patent Document 3 is a vibration means. Even if it is to be retrofitted to the vehicle body, it may not be installed in the vicinity of the engine or the position to be damped for reasons of installation space. In such a case, it is necessary to move the mounting position of the vibration means away from the engine and the position where vibration is to be suppressed. However, the vibration source (engine), vibration means (linear actuator), position where vibration is to be suppressed (seat part) However, there is a problem that optimal vibration control force cannot be obtained. In other words, the transmission characteristic from the vibration source to the position where vibration is to be controlled differs from the transmission characteristic from the position where the vibration means is provided to the position where vibration is to be controlled. The amplitude and phase cannot be determined uniquely from the engine speed. Each transfer characteristic is determined by the rigidity of the vehicle body, the response to the command of the vibration means, the filter characteristic of the acceleration sensor, and the like.

  In order to solve such a problem, the vibration damping device of Patent Document 2 predicts the generated vibration based on the vibration transmission characteristics, and determines the phase and amplitude of the damping force to be generated by the vibrating means. Therefore, vibration suppression control can be performed in consideration of vibration transfer characteristics.

  However, characteristics such as vehicle body rigidity that determine vibration transmission characteristics change due to aging and temperature changes. Therefore, the vibration transmission characteristics also change according to the changes in the characteristics of the vehicle body, taking into account the vibration transmission characteristics that have been obtained in advance. Thus, there is a problem that even if vibration suppression control is performed, the expected vibration control effect cannot be obtained.

  The present invention has been made in view of such circumstances, and maintains a high damping effect even in the case where the vibration transmission characteristics from the vibration excitation means to the vibration detection means change in the device to be controlled. An object is to provide a vibration damping device and a vehicle that can be continued.

The present invention includes a vibration detecting means for detecting vibration at a position to be damped transmitted from a vibration generating source and outputting it as a vibration signal, and provided at a position different from the position to be damped. The vibration control unit generates vibration control force from the vibration signal and a reference wave having a frequency component of vibration generated by the vibration generation source to cancel vibration at a position. An oscillation command generating means for outputting an excitation command for generating, an inverse characteristic of a vibration transmission characteristic from the excitation means to the vibration detecting means, and a phase correction amount, and the vibration signal and the excitation command Phase correction means for correcting the phase of the excitation command so that the phase difference matches the target phase angle.
In this configuration, the phase correction means includes the vibration command generated based on the transfer characteristic from the vibration means to the vibration detection means before being output from the vibration command generation means, and the vibration output from the vibration detection means. Find the phase difference from the signal. Then, the phase correction means corrects the phase of the excitation command before being output so that the obtained phase difference matches the target phase angle. Based on this correction, the vibration command generating means outputs a corrected vibration command. The vibration means generates a vibration damping force based on the corrected vibration command output from the vibration command generation means.
The target phase angle is a target value of the phase difference of the excitation command with respect to the vibration signal, and is 0 (zero) °, for example.
In other words, since the vibration command is generated by correcting the phase difference before and after the change of the vibration transfer characteristic to be the target phase angle, the vibration transfer characteristic of the device to be controlled changes due to secular change or temperature change. However, the expected vibration control effect can be obtained.

The phase correction means of the present invention is characterized in that when the phase difference between the vibration command and the vibration signal is within a preset range, the phase of the vibration command is corrected.
According to this configuration, by providing a dead zone in the phase correction, even if a slight frequency change occurs transiently at the vibration source or the position to be controlled, the control unit will follow the change excessively. Can prevent the control from becoming unstable. Note that whether or not the control tends to become unstable is also affected by whether or not the vibration of the vibration source is in the vicinity of the resonance frequency to be controlled, so the above-described threshold value may be set for each frequency. , It may be a constant value regardless of the frequency.

The phase correction means of the present invention may be arranged such that the phase of the vibration command is detected when the vibration detection means detects the frequency of the vibration source within a preset range and continuously for a preset number of times. Correction is performed.
According to this configuration, for example, when the frequency of f ± 1 Hz is detected by 10 samplings, the phase correction amount is updated or the phase correction is performed, so that the vibration generation source or the position to be controlled is transiently changed. Even when a minute change in frequency occurs, it is possible to prevent the control from becoming unstable due to the controller following the change excessively. Note that whether or not the control tends to become unstable is also affected by whether or not the vibration of the vibration source is in the vicinity of the resonance frequency to be controlled, so the above setting range or number of times is set for each frequency. Alternatively, it may be a constant value regardless of the frequency.

When the amplitude of the vibration command is output to the vibration means continuously within a preset range and a preset number of times, the phase correction means of the present invention Phase correction is performed.
According to this configuration, for example, when the amplitude fluctuation of the vibration command is within a range of ± 2% and 10 samples are output, the phase correction amount is updated or the phase correction is performed. Even when a minute frequency change occurs transiently at the position to be controlled, it is possible to prevent the control from becoming unstable due to the control unit following the change excessively. Note that whether or not the control tends to become unstable is also affected by whether or not the vibration of the vibration source is in the vicinity of the resonance frequency to be controlled, so the above setting range or number of times is set for each frequency. Alternatively, it may be a constant value regardless of the frequency.

The phase correction means of the present invention is characterized in that when the amplitude of the vibration signal is larger than a preset threshold value, the phase of the excitation command is corrected.
According to this configuration, for example, when the position to be damped is the seat of the vehicle, the acceleration amplitude of the vibration that the seated person feels large is set as the threshold value, so that if the position is greater than the threshold value, the vibration is reliably controlled. While providing a comfortable ride to the occupant by performing vibration, the calculation load can be reduced if the value is below the threshold value, and the phase correction amount is not updated or phase correction is not performed. Can be prevented. Note that, for example, since vibrations that are easily felt by humans vary depending on the frequency, the above-described threshold value may be set for each frequency, or may be a constant value regardless of the frequency.

The phase correction means of the present invention records the corrected result on a nonvolatile recording medium at a predetermined timing.
According to this configuration, for example, the phase correction amount for each vibration frequency can be stored in the recording medium at every predetermined timing such as when the vehicle is stopped or the engine is stopped, and can be read out at the time of restart and used for vibration control. That is, by using the phase correction amount that has been updated before restarting, vibration suppression control can be performed without a sense of incongruity even immediately after restarting. For this reason, it is possible to perform phase correction while maintaining a stable state after restarting.

The phase correction means of the present invention is characterized in that when the power is turned on or restarted, vibration suppression control is performed with a value obtained by multiplying the previously recorded phase correction amount by a predetermined value.
According to this configuration, for example, immediately after the power is turned on or restarted, the previously recorded phase correction amount can be multiplied by a predetermined value such as 0.5 and used for vibration suppression control. It is possible to perform phase correction while maintaining the state.

The phase correction means according to the present invention is characterized in that the phase correction is performed by a preset unit phase correction amount at a preset constant sampling period.
According to this configuration, since the phase correction is performed by the preset unit phase correction amount at every preset constant sampling cycle, the control is diverged by correcting the excessive correction amount at a time. Therefore, vibration control can be performed stably.

The phase correction means of the present invention performs correction by changing the unit phase correction amount according to the magnitude of the phase difference between the vibration signal and the excitation command.
According to this configuration, since the correction is performed by changing the unit phase correction amount according to the magnitude of the phase difference between the vibration signal and the vibration command, the unit is used when the difference from the target phase angle is relatively small. Preventing the control from diverging by reducing the phase correction amount, and, if relatively large, effectively correcting by increasing the unit phase correction amount, making it stable and efficient as a whole. Vibration control can be performed.

In addition, the vehicle of the present invention is characterized by including a vibration damping device.
According to the present invention, even when the vibration transmission characteristics of the vehicle change due to aging, temperature changes, etc., the vibration damping effect can be kept almost unchanged from that before aging, etc. Can provide a comfortable ride.

  According to the present invention, the magnitude of the damping force to be generated is based on the phase difference between the vibration at the position to be damped caused by the vibration source and the damping force for canceling the vibration. And the phase were corrected. For this reason, the expected damping effect can be obtained even when the vibration transmission characteristics of the damping target device change due to secular change or temperature change.

  Hereinafter, a vibration damping device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the embodiment. In this figure, reference numeral 1 denotes an engine (vibration generation source) mounted on the vehicle to generate a driving force for driving the vehicle such as an automobile, and is a generation source of vibration generated in the vehicle. Reference numeral 10 includes an auxiliary mass 11 having a predetermined mass, and a linear actuator that generates a damping force for suppressing vibration generated in the vehicle by a reaction force obtained by vibrating the auxiliary mass 11 (hereinafter referred to as a linear actuator). , “Actuator” (vibration means). Reference numeral 2 denotes a vehicle body frame of the vehicle. The engine 1 is mounted by an engine mount 1m, and the actuator 10 is mounted at a predetermined position. Here, the actuator 10 is assumed to suppress and control the vibration in the vertical direction (gravity direction) generated in the vehicle body frame 2.

  Reference numeral 3 denotes a control unit that performs control to generate vibration damping force in the actuator 10 and suppress vibration generated in the vehicle. Reference numeral 4 denotes an amplifier that supplies a current for driving the actuator 10 to the actuator 10 based on a command value output from the control unit 3. Reference numeral 5 denotes an acceleration sensor (vibration detecting means) mounted in the vicinity of a passenger seat 6 in the vehicle. Based on the engine pulse signal (ignition timing signal) output from the engine 1 and the acceleration sensor output signal output from the acceleration sensor 5, the control unit 3 obtains an excitation command for driving the actuator 10, Output to the amplifier 4. Based on this vibration command, the amplifier 4 obtains a current value to be supplied to the actuator 10 and supplies it to the actuator 10 so that the auxiliary mass reciprocates (in the example shown in FIG. ) And the reaction force can be used to reduce the vibration generated in the vicinity of the seat, which is the position to be damped.

  Here, a detailed configuration of the actuator 10 shown in FIG. 1 will be described with reference to FIG. FIG. 2 is a diagram showing a detailed configuration of the actuator 10 shown in FIG. In this figure, reference numeral 12 denotes a stator having a permanent magnet, which is fixed to the vehicle body frame 2. Reference numeral 13 denotes a mover that reciprocates in the same direction as the vibration direction to be suppressed (up and down movement on the paper surface of FIG. 2). Here, the body frame 2 is fixed to the body frame 2 so that the vibration direction to be suppressed coincides with the reciprocating direction (thrust direction) of the mover 13. Reference numeral 14 denotes a leaf spring that supports the movable element 13 and the auxiliary mass 11 so as to be movable in the thrust direction, and is fixed to the stator 12. Reference numeral 15 denotes a shaft that joins the mover 13 and the auxiliary mass 11 and is supported by a leaf spring 14. The actuator 10 and the auxiliary mass 11 constitute a dynamic vibration absorber.

  Next, the operation of the actuator 10 shown in FIG. 2 will be described. When an alternating current (sine wave current, rectangular wave current) is passed through a coil (not shown) constituting the actuator 10, the magnetic flux is changed from the S pole to the N pole in the permanent magnet in a state where a current in a predetermined direction flows through the coil. As a result, a magnetic flux loop is formed. As a result, the mover 13 moves in a direction against gravity (upward). On the other hand, when a current in a direction opposite to the predetermined direction is applied to the coil, the mover 13 moves in the direction of gravity (downward). The mover 13 repeats the above operation by alternately changing the direction of current flow to the coil by the alternating current, and reciprocates in the axial direction of the shaft 15 with respect to the stator 12. Thereby, the auxiliary mass 11 joined to the shaft 15 vibrates in the vertical direction. A dynamic vibration absorber composed of the actuator 10 and the auxiliary mass 11 is generated in the vehicle body frame 2 by controlling the acceleration of the auxiliary mass 11 and adjusting the damping force based on the current control signal output from the amplifier 4. The vibration can be reduced by canceling the vibration.

  Next, the vibration transmission characteristics of the vehicle body frame 2 shown in FIG. 1 will be described with reference to FIG. Here, the vibration source of the vehicle body frame 2 is assumed to be the engine 1 alone, and the vibration generated in the vehicle body frame 2 is described as suppressing the vibration generated in the vicinity of the passenger seat (driver's seat) 6. . The engine pulse for driving the engine 1 is a pulse that rises at the timing of ignition, and is output as a 40 Hz pulse signal if the rotational speed of the 4-cylinder engine 1 is 1200 rpm (FIG. 4 ( a)). In response to the engine pulse, each cylinder of the engine 1 is ignited, and vibrations synchronized with the ignition timing are generated from the engine 1 (see FIG. 4B). Vibration waves generated in the engine 1 reach the seat 6 through the vehicle body frame 2. The vibration transmission characteristic of the vehicle body frame 2 at this time is G ′. The vibration generated in the engine 1 changes in phase (for example, delayed by θ ′) and changes in amplitude due to the vibration transfer characteristic G ′ of the vehicle body frame 2 and appears as vibration of the seat 6. By detecting this vibration wave by the acceleration sensor 5, it is possible to detect the vibration generated in the seat 6 (see FIG. 4C). If vibration in the opposite phase of the vibration wave signal obtained by the acceleration sensor 5 (vibration wave indicated by a broken line in FIG. 4) is generated at the position of the seat 6, the vibration generated in the seat 6 can be canceled out. The vibration of the seat 6 can be suppressed.

  However, it may not be possible to provide a vibration source that generates a damping force for suppressing vibrations in the vicinity of the seat 6 due to vehicle layout limitations. For this reason, the actuator 10 shown in FIG. 1 may have to be provided at a position different from the position where vibration should be suppressed (position where the acceleration sensor 5 is provided). Therefore, the damping force generated by vibrating the auxiliary mass 11 is transmitted through the body frame 2 and reaches the seat 6. At this time, the phase and amplitude of the vibration wave generated in the actuator 10 change due to the transfer characteristic G of the body frame 2. Therefore, the vibration wave to be generated by the actuator 10 takes into account the phase change and amplitude change based on the vibration transfer characteristic G from the mounting position of the actuator 10 to the mounting position of the acceleration sensor 5 (position of the seat 6) (for example, , The phase is advanced by θ, the amplitude is increased, etc.), and a signal having a phase opposite to that of the output signal of the acceleration sensor 5 must be generated (see FIG. 4D). Therefore, if the damping force is generated in consideration of the phase change and the amplitude change based on the vibration transfer characteristic G from the mounting position of the actuator 10 to the mounting position of the acceleration sensor 5 (the position of the seat 6), the expected control is achieved. A vibration effect can be obtained. However, since the vibration transfer characteristic G changes due to secular change, temperature change, etc., the present invention corrects the vibration wave that the actuator 10 should generate in accordance with the change of the vibration transfer characteristic, so that the characteristic change occurs. Thus, even if the vibration transfer characteristic changes, an expected damping effect can be obtained.

  Next, referring to FIG. 3, the control unit 3 shown in FIG. 1 considers the phase change and amplitude change based on the vibration transfer characteristic G from the mounting position of the actuator 10 to the mounting position of the acceleration sensor 5. An operation for generating a vibration wave signal (vibration command) for generating a damping force in the means will be described. When generating a vibration wave signal, the control unit 3 generates an excitation command in which the amplitude and phase of the generated vibration wave are corrected according to the change in the vibration transfer characteristics. FIG. 3 is a control block diagram showing a detailed configuration of the control unit 3 shown in FIG. The control unit 3 inputs the output signal of the acceleration sensor 5 and the engine pulse signal of the engine 1 and outputs an excitation command to the amplifier 4.

  First, the control unit 3 considers the phase change and the amplitude change based on the vibration transfer characteristic G from the mounting position of the actuator 10 to the mounting position of the acceleration sensor 5, and generates a vibration wave signal ( The basic operation for generating the vibration command will be described.

  The BPF (band pass filter) 50 outputs Asin (ωt + φ) as a vibration signal among the output signals of the acceleration sensor 5. Here, Asin (ωt + φ) is a component of the frequency f of the engine pulse signal detected by the frequency detector 31 (ω = 2πf). The vibration signal output from the BPF 50 is a signal obtained by detecting the vibration generated at the present time. That is, since this vibration signal is a detection signal of vibration generated using the engine 1 as a vibration source, a signal in which the phase of this signal is inverted is generated, and the vibration transfer characteristic G of the signal having the inverted phase is generated. By giving an inverse characteristic (1 / G) and outputting it to the amplifier 4, vibration suppression control of vibration generated by using the engine 1 as a vibration source is performed.

  The signal (Asin (ωt + φ)) output from the BPF 50 is multiplied by a convergence gain of 2μ. The multipliers 33 and 34 multiply the multiplication results by the reference sine wave sin (ωt) and the reference cosine wave cos (ωt) output from the sine wave transmitter 32, respectively, and output the result to the integrators 35 and 36. . The integrators 35 and 36 integrate the outputs from the multipliers 33 and 34 and output signals having both an amplitude correction component and a phase difference component, respectively. That is, the integrator 35 outputs −A ′ cos φ ′ and the integrator 36 outputs −A ′ sin φ ′ to the multipliers 39, 40, 46 and 47. In FIG. 3 and the following description, the components detected by the acceleration sensor 5 are expressed as “A” and “φ”, and the components generated in the control unit 3 are “A ′” and “φ ′”. Is written.

The sine wave oscillator 32 generates a reference angle ωt from a frequency f of the engine pulse signal detected by the frequency detection unit 31 by a built-in electrical angle generation unit (not shown), and from the reference angle ωt, the reference wave sin (ωt) and reference wave cos (ωt) are output.
The value setting unit 37 includes an amplitude table and a phase table for the frequency f of the engine pulse signal. In these two tables, the result of the pre-measurement of the vibration transfer characteristics from the vibration means to the vibration detection means, that is, the transfer function G from the generated force of the actuator to the acceleration detected by the acceleration sensor before aging and temperature change. Based on the above, the amplitude component | 1 / G (jω) | and the phase component ∠1 / G (jω), which are the opposite characteristics, are recorded. The value setting unit 37 receives the frequency f of the engine pulse signal detected by the frequency detection unit 31, and the phase component ∠1 / G (jω) and the amplitude component | 1 / G (jω) related to the frequency f. ) | Is read from each of the two tables. Then, the value setting unit 37 outputs the phase component as P to the change amount suppression unit 42 and outputs the amplitude component as (1 / G) to the sine wave oscillator 38.
The sine wave oscillator 38 receives the frequency f, the amplitude component (1 / G) of the inverse characteristic of the vibration transfer characteristic G, and the output of the change gradient suppressing unit 45. Based on these input values, the sine wave oscillator 38 multiplies the inverse characteristic of the vibration transfer characteristic G (） 1 / G (jω) and | 1 / G (jω) |) by the reference sine wave (1 / G) sin (ωt + P + Δp) and reference cosine wave (1 / G) cos (ωt + P + Δp) are output. Here, Δp is a phase correction amount for correcting the phase component P of the inverse characteristic of the vibration transfer characteristic G, and details will be described later.

The adder 41 outputs (−A′cosφ ′) × (1 / G) sin (ωt + P + Δp) from the multiplier 39 and the output (−A′sinφ ′) × (1 / G) cos (ωt + P + Δp) from the multiplier 40. Are added, and-(A '/ G) sin (ωt + φ' + P + Δp) is output from the addition theorem. In other words, the vibration exciter 41 has an amplitude component of the inverse characteristic of the amplitude A ′ and the vibration transfer characteristic approximated to the amplitude A ′ (ωt + φ), which is a component of the frequency f of the engine pulse signal in the acceleration sensor output signal 1 / G), a signal obtained by correcting the phase difference φ ′ approximated with respect to the phase, the amplitude characteristic P of the inverse characteristic of the vibration transfer characteristic, and the phase correction amount Δp is output. Note that reference numeral (-1) is for 180 ° phase inversion with respect to the acceleration sensor output signal.
The output of the adder 41− (A ′ / G) sin (ωt + φ ′ + P + Δp) is an excitation command output to the bandpass filter 51.

The BPF 51 is a filter that passes frequencies near the frequency f. Note that f is the frequency of the engine pulse signal output from the frequency detector 31.
When the frequency to be controlled changes, in the transient state, there are multiple frequency components in the damping force. Therefore, for example, when the resonance frequency to be damped exists in the vicinity of the changed frequency, the damping force has a phase component different from the vibration phase that matches the resonance frequency and can reduce the resonance vibration. In some cases, the resonance frequency is vibrated and the control becomes unstable.
By removing the damping force other than the frequency to be damped by this BPF 51, it is possible to enhance the damping effect and prevent the control from becoming unstable.

  When the vibration command is output to the amplifier 4 via the bandpass filter 51, the auxiliary mass 11 vibrates and generates a damping force, thereby suppressing the vibration generated by the engine 1 detected by the acceleration sensor 5. It will be. At this time, the vibration damping force generated when the actuator 10 vibrates the auxiliary mass is a vibration damping force considering the phase change and amplitude change based on the vibration transfer characteristic G from the mounting position of the actuator 10 to the mounting position of the acceleration sensor 5. Since the force is a force, the generated vibration can be efficiently suppressed even if the position where the vibration is detected (the position of the seat 6) is different from the position where the damping force is generated.

  Next, the change amount suppression unit 42, the phase correction unit 43, the change gradient suppression unit 45, and the table correction unit 49 correct the phase of the excitation command with the phase correction amount Δp according to the change in vibration transfer characteristics due to secular change or the like. The operation | movement which performs is demonstrated.

The table correction unit 49 outputs (−A′sinφ ′) × cos (ωt) + (− A′cosφ ′) × sin (ωt) = − A′sin (ωt + φ ′) of the adder 48 and the engine pulse signal. Frequency f and Asin (ωt + φ) which is a component of frequency f of the acceleration sensor output signal. Then, the phase difference Δφ between the two input signals (−A′sin (ωt + φ ′) and Asin (ωt + φ)) is detected.
Here, Δφ is the difference between the component φ detected by the acceleration sensor 5 and the component φ ′ generated in the control unit 3 and is a numerical value of the change in vibration transfer characteristics due to secular change or the like. That is, as the vibration transfer characteristic in the actual vehicle body differs from the vibration transfer characteristic stored in the value setting unit 37 due to secular change or the like, Δφ becomes farther from zero.
In the present invention, the phase of the excitation command is corrected by the phase correction amount Δp so that Δφ becomes zero. Hereinafter, the phase correction amount Δp will be described.

  First, when there is no secular change or the like and there is no change in the vibration transfer characteristic G, Asin (ωt + φ) and (−A′sin (ωt + φ ′)) are in opposite phases as shown in FIG. That is, Asin (ωt + φ) and (−A′sin (ωt + φ ′)) coincide with each other at the time of the zero cross point at which the sign changes from negative to positive, for example. At this time, the vibration transmitted from the engine 1 to the position to be damped and the damping force generated by the actuator 10 cancel each other, and the vibration at the position to be damped is suppressed without performing phase correction. . Therefore, the table correction unit 49 determines that there is no need for phase correction.

  Next, the case where the vibration transfer characteristic G changes due to secular change or the like will be described. At this time, (−A′sin (ωt + φ ′)) is a phase advance of Δφ as shown in FIG. 10 (0 ≦ Δφ ≦ π) or a phase delay of Δφ as shown in FIG. 11 with respect to Asin (ωt + φ). (−π ≦ Δφ ≦ 0). The table correction unit 49 corrects the phase of the vibration command using the phase correction amount Δp when Δφ ≠ 0.

Here, a method of calculating the phase correction amount Δp will be described. The phase correction amount Δp is a function of the vibration frequency f of the engine pulse signal and is defined by the following equation.
Δp (f, n) = Δp (f, n−m) (φ = 0)
Δp (f, n) = Δp (f, n−m) −h (0 ≦ Δφ ≦ π)
Δp (f, n) = Δp (f, n−m) + h (−π ≦ Δφ ≦ 0)
Here, n and m are integers of n ≧ m, and h is a preset fixed angle as described above. That is, the phase correction amount Δp (f, n) in a certain sampling period is obtained by adding or subtracting 0 or h to Δp (f, mn) before the m sampling period.

  Then, the table correction unit 49 updates the correction value table 44 based on the obtained Δp value and the frequency f output from the frequency detection unit 31. FIG. 5 shows a table structure of the correction value table 44. As shown in FIG. 5, the correction value table 44 is a table in which the phase correction amount Δp is associated and stored for each frequency. The initial value of the table is, for example, “0” stored for all frequencies. The correction value table 44 is composed of a non-volatile memory, and the stored contents are retained even when the power is turned off.

When the phase correction amount is updated, the table correction unit 49 reads the phase correction amount related to the frequency to be updated, and a predetermined correction value h for bringing Δφ closer to 0 with respect to the phase correction amount. Is added. For example, in the example shown in FIG. 5, when the frequency f is 40 Hz, the phase correction amount Δp is defined as “−1 °” in the previous state (Δp (40 Hz, n−1) = − 1 °). . At this time, if a phase delay is detected, as shown in the following equation, for example, a predetermined value (for example, h) is set with respect to the phase correction amount Δp (40 Hz, n−1) one sampling period before. = 1 °).
Δp (40 Hz, n) = Δp (40 Hz, n−1) + 1 ° = 0 °
The reason why the value to be added is set to a predetermined small value is that the amount of calculation increases in order to accurately obtain Δφ, and there is a possibility that the control may become unstable if a large correction is performed once. Is the reason. The change in characteristics due to secular change does not change in a short time, so the value to be corrected at a time is set to a small value, and the correction is made gradually while keeping the control operation stable. With this operation, the correction value table 44 always stores a phase correction value when the vibration transfer characteristic G changes due to secular change or the like.

  On the other hand, the change amount suppression unit 42 holds the value of P output every m sampling periods, and compares the value of P output from the value setting unit 37 with the value of P output last time. When the difference is larger than a predetermined value (changeable upper limit), the value to be newly output is corrected so that the difference from the previously output P value does not exceed the predetermined value. And output (see FIG. 6). As described above, since the amount of change in the value of P output every m sampling periods is suppressed so as not to exceed the predetermined value, the control can be stably performed without divergence.

Next, the phase correction unit 43 reads the phase correction amount Δp related to the frequency output from the frequency detection unit 31 from the correction value table 44, and outputs the read phase correction amount from the change amount suppression unit 42. Is added to the signal. The signal (P + Δp) to which the phase correction amount is added is output to the change gradient suppression unit 45.
The change gradient suppression unit 45 holds the value of Δp output every m sampling periods inside so that the change gradient from Δp (f, nm) to Δp (f, n) becomes gentle. , The change amount is output for each change gradient limit value s. That is, for example, as shown in FIG. 7, the phase correction amount is changed from Δp (f, n−1) to the change gradient limit value s = {Δp (f, n) −Δp (f, n−1) for each sampling period. } / 4 in increments, and Δp (f, n) after 4 sampling periods. As described above, since the change gradient of P + Δp output every m sampling periods is suppressed, the control can be stably performed without divergence.
Here, the change gradient limit value s refers to a control value having a value smaller than the fixed angle h, and is set to 1/20 (0.05) of the fixed angle h, for example.

  By outputting this P + Δp to the sine wave oscillator 38, a vibration command to the actuator 10 is generated by the basic operation described above. That is, the generated vibration command is a signal that has been subjected to phase correction by the phase correction unit 43 in accordance with a change in vibration transfer characteristics due to secular change or the like.

  The phase correction unit 43 determines the phase correction amount when Δφ, which is the difference between the component φ detected by the acceleration sensor 5 and the component φ ′ generated in the control unit 3, is smaller than a predetermined threshold. Update may not be performed or phase correction may not be performed. In other words, by providing a dead zone for phase correction, even if a minute frequency change occurs transiently at the vibration source or the position to be controlled, the control unit will not follow the change excessively and control will not be possible. Stabilization can be prevented. Note that whether or not the control tends to become unstable is also affected by whether or not the vibration of the vibration source is in the vicinity of the resonance frequency to be controlled, so the above-described threshold value may be set for each frequency. , It may be a constant value regardless of the frequency.

  The phase correction unit 43 may update the phase correction amount or correct the phase when the frequency f of the vibration source is continuously detected within a preset range for a preset number of times. good. For example, when 10 samplings of the frequency of f ± 1 Hz are detected, the phase correction amount is updated or the phase correction is performed, so that a minute frequency change is transiently changed at the vibration source or the position to be controlled. Even if it occurs, it is possible to prevent the control from becoming unstable due to the control unit following the change excessively. Note that whether or not the control tends to become unstable is also affected by whether or not the vibration of the vibration source is in the vicinity of the resonance frequency to be controlled, so the above setting range or number of times is set for each frequency. Alternatively, it may be a constant value regardless of the frequency.

  In addition, the phase correction unit 43 updates the phase correction amount or corrects the phase when the amplitude of the vibration command is continuously output to the amplifier 4 within a preset range for a preset number of times. May be. For example, when the amplitude fluctuation of the vibration command is within the range of ± 2% and 10 samples are output, the phase correction amount is updated or the phase correction is performed, so that the vibration source or the position to be controlled is controlled. Even when a minute change in frequency occurs transiently, it is possible to prevent the control from becoming unstable due to the controller following the change excessively. Note that whether or not the control tends to become unstable is also affected by whether or not the vibration of the vibration source is in the vicinity of the resonance frequency to be controlled, so the above setting range or number of times is set for each frequency. Alternatively, it may be a constant value regardless of the frequency.

  The phase correction unit 43 may update the phase correction amount or correct the phase when the acceleration amplitude detected by the acceleration sensor 5 is larger than a preset threshold value. For example, if the position to be damped is the seat of a vehicle, the acceleration amplitude of vibration that a seated person feels large is set as a threshold value, and if it is above the threshold value, the occupant is surely damped. While providing a comfortable riding comfort, the calculation load can be reduced and the calculation error can be prevented due to the quantization error because the phase correction amount is not updated or the phase correction is not performed when it is below the threshold. Note that, for example, since vibrations that are easily felt by humans vary depending on the frequency, the above-described threshold value may be set for each frequency, or may be a constant value regardless of the frequency.

  Further, the correction value table 44 is not necessarily a non-volatile memory, and may be another rewritable recording medium. Further, for example, the phase correction amount for each vibration frequency may be stored in a recording medium at every predetermined timing such as when the vehicle is stopped or the engine is stopped, and may be read at the time of restart and used for vibration control. That is, by using the phase correction amount that has been updated before restarting, vibration suppression control can be performed without a sense of incongruity even immediately after restarting. When restarting, the previously recorded phase correction amount may be multiplied by a predetermined value such as 0.5 to be used for damping control.

  As described above, since the phase of the vibration command is corrected based on Δφ which is the difference between the component φ detected by the acceleration sensor 5 and the component φ ′ generated in the control unit 3, Even when the vibration transfer characteristic G of the vehicle body frame 2 changes due to the above or the like, a high vibration damping effect equivalent to that before the change can be obtained. In other words, even if it is necessary to correct the vibration transfer characteristic G preset in the vibration damping device due to secular change or the like, the vibration damping device can autonomously correct the amount of change in G. Without having to make any corrective work, the vibration control effect before aging can be maintained.

  Further, while obtaining the amplitude component 1 / G and the phase component P from the inverse characteristic table based on the frequency f of the engine pulse signal, the output -A'sin (ωt + φ ') of the adder 48 and the frequency of the acceleration sensor output signal The phase correction amount Δp is obtained so that the phase difference Δφ with respect to Asin (ωt + φ) which is the component of f becomes 0, and the phase of the vibration command is corrected by P and Δp. Therefore, for example, the calculation process can be simplified and the calculation time can be shortened as compared with the case where the inverse characteristic itself is calculated from the engine pulse signal and the acceleration sensor output signal. That is, not only can the control with good responsiveness be realized, but also the circuit necessary for the calculation can be configured at low cost, so that it is possible to provide the user with a vibration control device that is inexpensive and has high vibration control performance.

  Further, since the damping force is generated by taking into account the reverse characteristic of the vibration transmission characteristic from the vibration means to the vibration detection means, the actuator 10 as the vibration means can be placed at an arbitrary position on the body frame 2. Can be installed later. Therefore, for example, even when retrofitted to a used vehicle that has undergone aging, vibration control can be performed without requiring any complicated adjustment work. It is also possible to install it from the beginning on a new vehicle that does not change over time.

In the above description, the case of suppressing and controlling the vibration in the vertical direction (gravity direction) generated in the body frame 2 has been described. However, the direction of vibration to be controlled is not limited to the vertical direction, and vibration detection is performed. The detection position and direction of the means and the vibration position and direction of the vibration means can be changed as appropriate. For example, if the detection means is installed on the vehicle handle, vibration transmitted from the handle to the driver's hand can be reduced without being affected by aging.
Further, the linear actuator 10 shown in FIG. 2 is used to generate a damping force. However, any driving source that can generate a reaction force that can suppress vibration by vibrating the auxiliary mass 11 can be used. For example, any means for vibrating the auxiliary mass 11 may be used.
The control unit 3 is also used as an excitation command generation unit and a phase correction unit. Specifically, the control unit 3 includes a sine wave oscillator 32, a gain of 2 μ, multipliers 33 and 34, integrators 35 and 36, and an addition. The device 41 functions as a vibration command generation means. The phase correction unit 43, the correction value table 44, the sine wave oscillator 38, and the multipliers 39 and 40 function as phase correction means.

  The vibration damping device according to the present invention can be applied to a vibration suppressing application in a case where a position where vibration is to be suppressed and a position where a damping force is generated are different. Further, in the above description, the vibration suppression target is described as being a vehicle body frame. However, the device to be controlled by the vibration suppression device of the present invention does not necessarily have to be a vehicle body frame. It may be a car body or a robot arm.

It is a block diagram which shows the structure of one Embodiment of this invention. It is a schematic diagram which shows the structure of the actuator 10 shown in FIG. It is a block diagram which shows the structure of the control part 3 shown in FIG. It is explanatory drawing which shows the vibration transmission characteristics G and G 'of the vehicle body frame 2 shown in FIG. It is explanatory drawing which shows the table structure of the correction value table 44 shown in FIG. It is explanatory drawing which shows operation | movement of the variation suppression part 42 shown in FIG. It is explanatory drawing which shows operation | movement of the change gradient suppression part 45 shown in FIG. It is explanatory drawing which shows operation | movement of the table correction | amendment part 49 shown in FIG. It is explanatory drawing which shows the phase shift state of the produced | generated signal and the detected signal. It is explanatory drawing which shows the phase shift state of the produced | generated signal and the detected signal. It is explanatory drawing which shows the phase shift state of the produced | generated signal and the detected signal.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Body frame, 3 ... Control part (Excitation command generation means, Phase correction means), 4 ... Amplifier, 5 ... Acceleration sensor (vibration detection means), 6 ... Seat, 10 ... Actuator (linear actuator, excitation means), 11 ... Auxiliary mass, 31 ... Frequency detector, 32, 38 ... Sine wave oscillator, 37 ... Value Setting unit, 42... Change amount suppressing unit, 43... Phase correcting unit, 44... Correction value table, 45.・ BPF (band pass filter)

Claims (10)

A vibration detection means for detecting vibration at a position to be damped transmitted from a vibration source and outputting it as a vibration signal;
An excitation means that is provided at a position different from the position to be damped, and generates a damping force to cancel the vibration at the position to be damped;
Excitation command generation means for outputting an excitation command for generating the damping force in the excitation means from the vibration signal and a reference wave having a frequency component of the frequency of vibration generated by the vibration generation source. When,
The excitation command so that the phase difference between the vibration signal and the excitation command matches the target phase angle based on the inverse characteristic of the vibration transfer characteristic from the excitation unit to the vibration detection unit and the phase correction amount. And a phase correcting means for correcting the phase of the vibration damping device.   2. The phase correction unit according to claim 1, wherein the phase of the excitation command is corrected when a phase difference between the excitation command and the vibration signal is within a preset range. The vibration damping device described.   The phase correction means corrects the phase of the vibration command when the frequency of the vibration generation source is detected by the vibration detection means within a preset range and continuously for a preset number of times. The vibration damping device according to claim 1 or 2, wherein   The phase correction means corrects the phase of the excitation command when the amplitude of the excitation command is output to the excitation means within a preset range and continuously for a preset number of times. The vibration damping device according to claim 1, wherein the vibration damping device is performed.   5. The vibration damping device according to claim 1, wherein the phase correction unit corrects the phase of the vibration command when the amplitude of the vibration signal is larger than a preset threshold value.   6. The vibration damping device according to claim 1, wherein the phase correction unit records the corrected result on a nonvolatile recording medium at a predetermined timing.   7. The vibration damping device according to claim 6, wherein when the power is turned on or restarted, the phase correction unit performs vibration suppression control with a value obtained by multiplying the previously recorded phase correction amount by a predetermined value.   8. The vibration damping device according to claim 1, wherein the phase correction means performs the phase correction by a preset unit phase correction amount at a preset constant sampling period.   9. The vibration damping device according to claim 8, wherein the phase correction unit performs correction by changing the unit phase correction amount in accordance with a magnitude of a phase difference between the vibration signal and the vibration command. . A vehicle comprising the vibration damping device according to any one of claims 1 to 9.

Images