Frequency detector for reciprocating moving body, and swinging joint device

Patent metadata

Field	Value
Publication number	US-10386207-B2
Application number	US-201715431151-A
Country	US
Kind code	B2
Filing date	Feb 13, 2017
Priority date	Feb 15, 2016
Publication date	Aug 20, 2019
Grant date	Aug 20, 2019

Abstract

A frequency detector includes an oscillation related information output portion to which moving body position related information and a correction parameter are input, and which outputs a frequency adjustment parameter and estimated moving body position related information; a frequency estimating portion to which the frequency adjustment parameter is input, and which outputs an estimated frequency; and an adjusting portion to which the moving body position related information, the estimated moving body position related information, and the estimated frequency are input, and which outputs the correction parameter.

First claim

What is claimed is:

1. A frequency detector for a reciprocating moving body having a rigidity adjustment electric motor, the frequency detector being configured to detect a frequency of a motion waveform based on a motion trajectory of the reciprocating moving body that performs reciprocating motion, the frequency detector comprising:
an oscillation related information output portion to which moving body position related information is input, and which performs oscillation in synchronization with the reciprocating motion of the reciprocating moving body based on the input moving body position related information, and outputs oscillation related information that is information related to an oscillation waveform based on the oscillation, the moving body position related information being related to a position of the reciprocating moving body varied with a lapse of time;
a frequency estimating portion that outputs an estimated frequency of the motion waveform, the estimated frequency being a frequency of the oscillation waveform estimated based on the oscillation related information; and
an adjusting portion that determines a correction parameter for the oscillation related information output portion so as to cause the frequency of the motion waveform and the estimated frequency to coincide with each other, wherein
the oscillation related information output portion outputs i) a frequency adjustment parameter that is one of pieces of the oscillation related information and is a parameter adjusted based on the correction parameter from the adjusting portion, and ii) estimated moving body position related information that is one of the pieces of the oscillation related information and is estimated as the position of the reciprocating moving body based on the moving body position related information,
the frequency estimating portion outputs the estimated frequency determined based on the frequency adjustment parameter that is output from the oscillation related information output portion,
the adjusting portion determines a correction parameter for correcting an operation of the oscillation related information output portion, based on the moving body position related information, the estimated moving body position related information, and the estimated frequency, and
the adjusting portion adjusts the estimated frequency output from the frequency estimating portion by outputting the determined correction parameter to the oscillation related information output portion to adjust the frequency adjustment parameter and the estimated moving body position related information that are output from the oscillation related information output portion,
whereby a rotation angle of the electric motor is controlled based on the adjusted estimated frequency output.

2. The frequency detector for the reciprocating moving body according to claim 1 , wherein:
the moving body position related information is input to the oscillation related information output portion and the adjusting portion after the moving body position related information passes through a first filter; and
the correction parameter is input to the oscillation related information output portion after the correction parameter passes through a second filter.

3. The frequency detector for the reciprocating moving body according to claim 1 , wherein
the reciprocating motion is a periodic reciprocating swinging motion, and the moving body position related information is a swinging angle related to the position of the reciprocating moving body varied with the lapse of time.

4. The frequency detector for the reciprocating moving body according to claim 1 , wherein
in a case where x 1 is membrane potential of a neuron and is a state variable for f(x 1 ), x 2 is membrane potential of a neuron and is a state variable for f(x 2 ), f(x 1 ) and f(x 2 ) are outputs of the neurons on condition that f(x j )=max(0, x j ), v 1 is a variable indicating a degree of adaptation and is a state variable for f(v 1 ), v 2 is a variable indicating a degree of adaptation and is a state variable for f(v 2 ), f(v 1 ) and f(v 2 ) are variables respectively indicating degrees of adaptation on condition that f(v j )=max(0, v j ), β is a constant determining a change in adaptation over time and is adaptation strength, γ is a constant determining a change in adaptation over time and is a coupling coefficient for two adaptive elements, u 0 is an external input that is a uniform constant, T 1 is the frequency adjustment parameter, T 2 is a parameter to be adjusted and is a time constant, b is a parameter to be adjusted and is an input coefficient, c is a parameter to be adjusted and is an output coefficient, θ fltr is the moving body position related information, and θ neuro is the estimated moving body position related information, the oscillation related information output portion performs the oscillation based on the input moving body position related information and outputs the frequency adjustment parameter and the estimated moving body position related information that are adjusted based on the correction parameter from the adjusting portion, by using a mathematical model including a neural oscillation having relationships of
T 1 {dot over (x)} 1 +x 1 =γf ( x 2 )+ b ( u 0 +θ fltr )−β f ( v 1 )

T 2 {dot over (v)} 1 +v 1 =f ( x 1 )
T 1 {dot over (x)} 2 +x 2 =−γf ( x 1 )+ b ( u 0 −θ fltr )−β f ( v 2 )

T 2 {dot over (v)} 2 +v 2 =f ( x 2 )
θ neuro =cf ( x 1 )− cf ( x 2 );

in a case where c 1 and c 2 are constants of a frequency estimation calibration expression, f calc is the estimated frequency, and a ratio of T 1 /T 2 is uniform, the frequency estimating portion outputs the estimated frequency determined based on a relationship of f calc =(c 1 /T 1 )+c 2 and the frequency adjustment parameter output from the oscillation related information output portion; and
in a case where K p1 and K p2 are parameter adjustment gains that are constants, sgn(x) is a signum function that becomes 1 when x>0, becomes 0 when x=0, and becomes −1 when x<0, and ΔT 1 is the correction parameter, the adjusting portion determines the correction parameter based on a relationship of
Δ T 1 =( K p1 /f calc ){sgn(θ neuro )[({dot over (θ)} fltr )−({dot over (θ)} neuro )]}−( K p2 /f calc )(|{dot over (θ)} fltr |−|{dot over (θ)} neuro |),

the moving body position related information, the estimated moving body position related information, and the estimated frequency, and the adjusting portion adjusts the estimated frequency output from the frequency estimating portion by outputting the determined correction parameter to the oscillation related information output portion to adjust the frequency adjustment parameter and the estimated moving body position related information that are output from the oscillation related information output portion.

5. A swinging joint device that includes a frequency detector for a reciprocating moving body, the frequency detector being configured to detect a frequency of a motion waveform based on a motion trajectory of the reciprocating moving body that performs reciprocating motion, the frequency detector comprising:
an oscillation related information output portion to which moving body position related information is input, and which performs oscillation in synchronization with the reciprocating motion of the reciprocating moving body based on the input moving body position related information, and outputs oscillation related information that is information related to an oscillation waveform based on the oscillation, the moving body position related information being related to a position of the reciprocating moving body varied with a lapse of time;
a frequency estimating port

Assignees

• Jtekt Corp

Inventors

• Yoshimi Yoshitaka
• Ohta Hiromichi

Classifications

• A61H2201/1652

  Harness · CPC title

• A61H1/0244

  Hip (A61H1/0255 takes precedence) · CPC title

• A61H2201/0192

  Specific means for adjusting dimensions · CPC title

• A61H2201/1614

  Shoulder, e.g. for neck stretching · CPC title

• A61H3/008

  using suspension devices for supporting the body in an upright walking or standing position, e.g. harnesses · CPC title