JP2012002540A - Sensor output correction circuit and correction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain linearity between a curvature given to a curvature sensor using a solid polymer electrolyte and an output voltage from the curvature sensor.SOLUTION: A sensor output correction circuit 100 corrects the output voltage which is output by a sensor 200 having a pair of electrodes and a solid polymer electrolyte layer formed between the electrodes, based on the given curvature. The sensor output correction circuit includes a monitoring circuit 102 for monitoring the variation quantity of the output voltage; a state determination circuit 103 for determining that the sensor is in a static state when the variation quantity is smaller than a prescribed value, and sets a target voltage; and a correction current generation circuit 104 for injecting, to the sensor 200, an amount of electric charges corresponding to a deviation between the output voltage and the target voltage so as to make the output voltage closer to the target voltage, when the static state is determined.

Description

  The present invention relates to a sensor output correction circuit and a correction method, and more particularly to a correction circuit and a correction method for a curvature sensor using a solid polymer electrolyte.

  In recent years, in the fields of medical care equipment, industrial robots, personal robots, etc., there is an increasing need for small and lightweight sensors. In addition, as a strain sensor and a vibration sensor, there is an increasing need for a lightweight and flexible sensor that can be installed in a complex-shaped structure.

  As such a light and flexible sensor, Patent Document 1 discloses a deformation sensor using a solid polymer electrolyte (SPE), particularly a non-aqueous polymer solid electrolyte. This sensor generates an electromotive force by deformation of the sensor element. Moreover, since a non-aqueous polymer solid electrolyte is used, it has high response sensitivity stably in the air.

  Further, in the deformation sensor described in Patent Document 1, as described in Non-Patent Document 1, there is a proportional relationship (linearity) between the curvature imparted to the flexible sensor and the output voltage from the sensor. It is known to have. Therefore, as a specific application of the deformation sensor described in Patent Document 1, a curvature (bending deformation) sensor is particularly promising. This curvature sensor can detect a wide range of curvature. In addition, when the deformation is maintained, a substantially constant voltage can be continuously generated. Furthermore, since a bias voltage is not required, the power consumption is low.

International Publication No. 2009/096419 Pamphlet

Otsuki and two others, “Characteristic Evaluation of Curvature Sensor Using Solid Polymer Electrolyte”, 18th MAGDA Conference in Tokyo, Conference on Electromagnetic Phenomena and Electromagnetic Force, 2009, p. 165-170

  FIG. 10 is a schematic graph for explaining the problem to be solved by the present invention. In FIG. 10, the horizontal axis represents time, and the vertical axis represents the output voltage of the curvature sensor. The case where the same curvature is repeatedly given in the fixed time interval is shown. As shown in FIG. 10, when the number of repetitions increases, the output voltage gradually decreases despite the same curvature being applied. That is, there is a problem that the linearity between the curvature applied to the curvature sensor and the output voltage from the curvature sensor is not maintained.

  The present invention has been made in view of the above, and a sensor output correction circuit and correction for maintaining linearity between a curvature applied to a curvature sensor using a solid polymer electrolyte and an output voltage from the curvature sensor. It aims to provide a method.

A first aspect according to the present invention includes:
A pair of electrodes;
A sensor comprising a solid polymer electrolyte layer formed between the pair of electrodes,
A correction circuit that corrects an output voltage to be output according to a given curvature,
A monitoring circuit for monitoring the amount of change in the output voltage;
When the amount of change is smaller than a predetermined reference value, it is determined that the sensor is in a stationary state, and a state determination circuit that sets a target voltage;
A correction current generating circuit for injecting an amount of electric charge corresponding to a difference between the output voltage and the target voltage in a direction in which the output voltage approaches the target voltage when it is determined that the sensor is in the stationary state; , A sensor output correction circuit.
Thereby, the linearity between the curvature provided to the sensor and the output voltage from the sensor can be maintained.

According to a second aspect of the present invention, in the first aspect,
The state determination circuit determines that the sensor is in an operating state when the amount of change is greater than a predetermined reference value.
When it is determined that the sensor is in the operating state, the correction current generation circuit is a sensor output correction circuit that injects electric charges into the sensor in a direction that reduces the amount of change.
Thereby, the linearity between the curvature provided to a sensor and the output voltage from a sensor can be hold | maintained more reliably.

According to a third aspect of the present invention, in the second aspect,
When it is determined that the sensor is in the operating state, the amount of the electric charge injected into the sensor is constant irrespective of the amount of change.
Thereby, it can correct | amend more rapidly.

According to a fourth aspect of the present invention, in any one of the first to third aspects,
When it is determined that the sensor is in a stationary state, the amount of the electric charge injected into the sensor is PWM-controlled. PWM control is suitable as a specific control method.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects,
A sensor output correction circuit, wherein the monitoring circuit includes an integration circuit. It is suitable as a specific circuit configuration.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects,
A sensor output correction circuit, wherein the monitoring circuit includes a differentiation circuit. It is suitable as a specific circuit configuration.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects,
2. The sensor output correction circuit according to claim 1, wherein the solid polymer electrolyte layer is a non-aqueous polymer solid electrolyte layer. It is suitable as a specific circuit configuration.

An eighth aspect according to the present invention is as follows.
A pair of electrodes;
A sensor comprising a solid polymer electrolyte layer formed between the pair of electrodes,
A correction method for correcting an output voltage to be output according to a given curvature,
Monitoring the amount of change in the output voltage;
When the amount of change is smaller than a predetermined reference value, determining that the sensor is stationary and setting a target voltage;
A step of injecting an amount of electric charge corresponding to a difference between the output voltage and the target voltage in a direction in which the output voltage approaches the target voltage when it is determined that the sensor is in a stationary state. This is an output correction method.
Thereby, the linearity between the curvature provided to the sensor and the output voltage from the sensor can be maintained.

According to a ninth aspect of the present invention, in the eighth aspect,
Determining that the sensor is in an operating state if the amount of change is greater than a predetermined reference value;
And a step of injecting electric charge in a direction to mitigate the amount of change when the sensor is determined to be in the operation state.
Thereby, the linearity between the curvature provided to a sensor and the output voltage from a sensor can be hold | maintained more reliably.

According to a tenth aspect of the present invention, in the ninth aspect,
In the sensor output correction method, when it is determined that the sensor is in the operation state, the amount of the electric charge injected into the sensor is constant regardless of the amount of change.
Thereby, it can correct | amend more rapidly.

According to an eleventh aspect of the present invention, in any one of the eighth to tenth aspects,
In the sensor output correction method, the amount of the electric charge injected into the sensor is subjected to PWM control when it is determined that the sensor is in the stationary state. PWM control is suitable as a specific control method.

According to a twelfth aspect of the present invention, in any one of the eighth to eleventh aspects,
2. The sensor output correction circuit according to claim 1, wherein the solid polymer electrolyte layer is a non-aqueous polymer solid electrolyte layer. It is particularly suitable as a method for correcting the output voltage of a sensor using a non-aqueous polymer solid electrolyte layer.

  According to the present invention, it is possible to provide a sensor output correction circuit and a correction method for maintaining linearity between a curvature applied to a curvature sensor using a solid polymer electrolyte and an output voltage from the curvature sensor. it can.

2 is a block diagram of a curvature sensor including a correction circuit according to Embodiment 1. FIG. 5 is a flowchart for explaining a correction method according to the first embodiment. 3 is a timing chart for explaining the operation of the correction circuit according to the first embodiment. It is sectional drawing which shows the structure of the curvature sensor 200 which concerns on an Example and a comparative example. It is a graph which shows the change of an output voltage at the time of continuing providing the bending deformation amount (curvature) from which an output voltage will be about 450 microvolts. It is a graph which shows the change of an output voltage at the time of continuing providing the bending deformation amount (curvature) from which an output voltage will be about 450 microvolts. It is a graph which shows the change of an output voltage at the time of canceling this bending deformation, after giving the amount of bending deformation (curvature) which becomes about 450 microvolts of output voltage. It is a graph which shows the change of an output voltage at the time of canceling this bending deformation, after giving the amount of bending deformation (curvature) which becomes about 450 microvolts of output voltage. It is a graph which shows the change of an output voltage at the time of giving repeatedly the bending deformation amount (curvature) from which an output voltage will be about 75 microvolts about every 1 second. It is a graph which shows the change of an output voltage at the time of giving repeatedly the bending deformation amount (curvature) from which an output voltage will be about 75 microvolts about every 1 second. It is a graph which shows the change of an output voltage at the time of giving repeatedly the bending deformation amount (curvature) from which an output voltage will be about 250 microvolts about every 2 seconds. It is a graph which shows the change of an output voltage at the time of giving repeatedly the bending deformation amount (curvature) from which an output voltage will be about 250 microvolts about every 2 seconds. It is a graph which shows the change of an output voltage when the amount of bending deformation (curvature) in which an output voltage becomes about 250 microvolts is divided and given repeatedly in five steps about every 2 seconds. It is a graph which shows the change of an output voltage when the amount of bending deformation (curvature) in which an output voltage becomes about 250 microvolts is divided and given repeatedly in five steps about every 2 seconds. It is a typical graph for explaining a subject which the present invention tends to solve.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiment. In addition, for clarity of explanation, the following description and drawings are simplified as appropriate.

(Embodiment 1)
A curvature sensor provided with a correction circuit according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of a curvature sensor including a correction circuit according to the first embodiment. The correction circuit 100 shown in FIG. 1 includes an A / D (analog / digital) conversion circuit 101, an integration circuit 102, an integration result determination circuit 103, and a correction current generation circuit 104. The curvature sensor 200 includes an upper electrode 202a, a lower electrode 202b, and an SPE layer 201.

  FIG. 1 shows a schematic cross-sectional view of the curvature sensor 200. The SPE layer 201 is a non-aqueous polymer solid electrolyte layer. As a specific non-aqueous polymer solid electrolyte, for example, a known non-aqueous polymer solid electrolyte disclosed in Patent Document 1 and Japanese Patent Application Laid-Open No. 2007-336790 can be used. The SPE layer 201 is sandwiched between the upper electrode 202a and the lower electrode 202b. Here, as the upper electrode 202a and the lower electrode 202b, for example, a known carbon electrode disclosed in Patent Document 1 can be used. A conductive material such as silver paste is applied to the outer surfaces of the upper electrode 202a and the lower electrode 202b (not shown).

  The actual curvature sensor 200 has a film shape and is flexible. When this film-like curvature sensor 200 itself is bent and deformed, that is, when a curvature is given to the curvature sensor 200, an electromotive force corresponding to the curvature is generated. That is, as shown in FIG. 1, when a curvature is applied to the curvature sensor 200, an electromotive force Va corresponding to the curvature is generated between the upper electrode 202a and the lower electrode 202b. The conventional curvature sensor 200 only detects an electromotive force Va according to the curvature. Here, when the electromotive force when the curvature sensor 200 is bent in a certain direction is a positive value, the electromotive force when bent in the opposite direction is a negative value.

  On the other hand, the correction circuit 100 is connected to the curvature sensor 200 according to the present embodiment. As described above, the correction circuit 100 illustrated in FIG. 1 includes the A / D conversion circuit 101, the integration circuit 102, the integration result determination circuit 103, and the correction current generation circuit 104. The analog electromotive force Va generated in the curvature sensor 200 is input to the A / D conversion circuit 101.

  The A / D conversion circuit 101 converts the analog electromotive force Va into a digital output voltage Vd and outputs it. This digital output voltage Vd is monitored as a measured value. That is, the curvature as the measurement target can be calculated backward from the digital output voltage Vd.

  On the other hand, the digital output voltage Vd output from the A / D conversion circuit 101 is input to the integration circuit 102. The integrating circuit 102 integrates the digital output voltage Vd every predetermined period. Then, the integration result output from the integration circuit 102 is input to the integration result determination circuit 103.

  The integration result determination circuit 103 determines that the curvature sensor 200 is in an operating state when the change amount of the output voltage is large, that is, when the output voltage is greater than or equal to a predetermined reference value. On the other hand, when the change amount of the output voltage is small, that is, smaller than the predetermined reference value, it is determined that the curvature sensor 200 is in a stationary state.

  If it is determined that the operation state is established, the integration result determination circuit 103 generates the polarity signal s1 indicating the direction in which the change in the output voltage is relaxed. The direction of the correction current output from the correction current generation circuit 104, that is, either the correction current I1 or I2 is selected in accordance with the polarity signal s1. In this case, the integration result determination circuit 103 generates a pulse width control signal s2 for outputting a constant charge amount.

  On the other hand, if it is determined that it is in the stationary state, the integration result determining circuit 103 sets the target voltage closer to the upper and lower setting control fluctuation ranges corresponding to the output voltage range in the stationary state. Then, a polarity signal s1 corresponding to the polarity of the difference between the integration result of the output voltage and the integration result of the target voltage, that is, whether the difference is a positive value or a negative value is generated. Specifically, the polarity signal s1 is a signal indicating the direction in which the output voltage approaches the target voltage. In this case, the integration result determination circuit 103 generates the pulse width control signal s2 corresponding to the magnitude (absolute value) of the difference between the integration result of the output voltage and the integration result of the target voltage.

  The polarity signal s1 and the pulse width control signal s2 are input to the correction current generation circuit 104. The correction current generation circuit 104 outputs one of the correction currents I1 and I2 according to the polarity signal s1. For example, when the polarity signal s1 that is a digital signal is H, the correction current I1 supplied to the upper electrode 202a is output from the correction current generation circuit 104. Here, the correction current I2 supplied to the lower electrode 202b is not output from the correction current generation circuit 104. Conversely, when the polarity signal s1 is L, the correction current I1 supplied to the upper electrode 202a is not output from the correction current generation circuit 104, and only the correction current I2 supplied to the lower electrode 202b is output from the correction current generation circuit 104. Is output.

  Further, the correction current generation circuit 104 outputs a correction current I1 or I2 having a constant value for a time corresponding to the pulse width control signal s2. That is, the amount of charge injected into the curvature sensor 200 is controlled by PWM control. Here, when it is determined that the integration result determination circuit 103 is in the operating state, the correction current generation circuit 104 outputs the correction current I1 or I2 having a constant value for a predetermined time according to the pulse width control signal s2. That is, a certain amount of charge is always injected into the curvature sensor 200. By injecting a certain amount of charge in a time-dependent manner, it is possible to make a quick correction with little hysteresis and no steep fluctuation.

  On the other hand, if it is determined by the integration result determination circuit 103 that there is a stationary state, if the difference between the integration result of the output voltage and the integration result of the target voltage is large, the time for which the correction current I1 or I2 having a constant value is output As a result, the amount of charge injected into the curvature sensor 200 increases. On the contrary, if the difference between the integration result of the output voltage and the integration result of the target voltage is small, the time during which the correction current I1 or I2 having a constant value is output is shortened, and the amount of charge injected into the curvature sensor 200 is also reduced. .

  As described above, when the curvature sensor 200 keeps the curvature constant, the curvature sensor 200 continues to output a substantially constant electromotive force according to the curvature. However, strictly speaking, when it is held for a long time, for example, in the case of a positive electromotive force, there is a problem that the electromotive force gradually decreases and the linearity between the curvature and the electromotive force deteriorates. However, by supplying the correction current to the curvature sensor 200, a constant electromotive force can be maintained. Therefore, the linearity between the curvature and the electromotive force can be maintained.

  When the change amount of the output voltage is small as in the case where the curvature is held constant, the correction current generation circuit 104 outputs a charge amount corresponding to the deviation of the output voltage from the target voltage to the curvature sensor 200. On the other hand, when the change amount of the output voltage is large and exceeds a predetermined reference value, a constant charge is output to the curvature sensor 200 regardless of the change amount of the output voltage so as to alleviate this voltage fluctuation. In this case, the fixed injection charge amount may be determined after appropriate adjustment.

  The case where the change amount of the output voltage exceeds a predetermined reference value is specifically, for example, when bending deformation is applied or when bending deformation is released. In such a case, a rising overshoot or a falling overshoot occurs. However, such overshoot can be reduced by supplying the correction current to the curvature sensor 200. Thereby, the linearity between the curvature and the electromotive force can be maintained with higher accuracy.

  Moreover, the correction circuit 100 according to the present embodiment is directly connected to the electrode terminal of the curvature sensor 200 and does not require any change in the curvature sensor 200 itself. Therefore, features such as thinness, lightness, and flexibility of the curvature sensor 200 are not impaired. Further, unlike the normally considered correction method, it is not necessary to output the electromotive force generated in the curvature sensor 200 by performing mathematical arithmetic processing in accordance with the algorithm. As a result, the output voltage can be output while being controlled by the correction charge, which is excellent in real time. Furthermore, the correction method according to the present invention is a very original method in which charges are directly injected into the solid polymer electrolyte that constitutes the curvature sensor 200 based on the characteristics of the solid polymer electrolyte.

  Next, the correction method according to the present embodiment will be described with reference to FIG. FIG. 2 is a flowchart for explaining the correction method according to the first embodiment. As shown in FIG. 2, the amount of change in the output voltage is monitored (step ST1). In the example of FIG. 1, the change amount of the output voltage is monitored by the integration circuit 102. Next, it is determined whether or not the change amount of the output voltage is equal to or less than a reference value (step ST2). In the example of FIG. 1, the integration result determination circuit 103 determines.

  Here, if the change amount of the output voltage is not large and not less than the reference value (NO in step ST2), it is determined that the operation state is established, and a certain amount of charge is injected into the curvature sensor 200 in a direction to mitigate the change of the output voltage. (Step ST3). And it returns to step ST1 again and the variation | change_quantity of an output voltage is measured.

  On the other hand, if the amount of change in the output voltage is small and not more than the reference value (YES in step ST2), it is determined that it is in a stationary state, the target voltage is set, and the deviation between the output voltage and the target voltage is calculated (step ST4). . Then, an amount of charge corresponding to the difference between the output voltage and the target voltage is injected in the direction in which the output voltage approaches the target voltage (step ST5). And it returns to step ST1 again and the variation | change_quantity of an output voltage is measured.

  Next, the operation of the correction circuit 100 in FIG. 1 will be described with reference to FIG. FIG. 3 is a timing chart for explaining the operation of the correction circuit according to the first embodiment. FIG. 3 shows a correction operation for maintaining the target voltage when the change amount of the output voltage is small. The uppermost stage in FIG. 3 shows the digital output voltage Vd output from the A / D conversion circuit 101. The second row shows the polarity signal s1 output from the integration result determination circuit 103. The third row shows the pulse width control signal s2 output from the integration result determination circuit 103. The bottom row shows the correction current I1 or I2 (injected charge amount) output from the correction current generation circuit 104.

  As shown in FIG. 3, the output voltage Vd is integrated at equal sampling times, and a polarity signal s1 and a pulse width control signal s2 are generated based on the integration result. First, as shown in FIG. 3, the difference between the integration result of the output voltage Vd and the integration result of the target voltage becomes a positive value during the sampling time up to the time T1. Therefore, the polarity signal s1 that is a digital signal becomes L at time T1. Further, at time T1, the pulse width control signal s2 becomes H by the width W1 according to the magnitude (absolute value) of the difference between the integration result of the output voltage Vd and the integration result of the target voltage. As a result, the charge of I2 × W1 is supplied to the lower electrode 202b of the curvature sensor 200 at time T1. As a result, the output voltage Vd approaches the target voltage.

  In the sampling time from time T1 to time T2, since the output voltage Vd is always larger than the target voltage, the difference between the integration result of the output voltage Vd and the integration result of the target voltage is a positive value. Therefore, the polarity signal s1, which is a digital signal, remains L at time T2. Further, at time T2, the pulse width control signal s2 becomes H by the width W2 according to the magnitude (absolute value) of the difference between the integration result of the output voltage Vd and the integration result of the target voltage. As a result, the charge of I2 × W2 is supplied to the lower electrode 202b of the curvature sensor 200 at time T2. As a result, the output voltage Vd approaches the target voltage.

  In the sampling time from time T2 to time T3, the difference between the integration result of the output voltage Vd and the integration result of the target voltage width is negative and has a minimum value. Therefore, the polarity signal s1 which is a digital signal is switched to H at time T3. Further, since the difference between the integration result of the output voltage Vd and the integration result of the target voltage is 0, the pulse width control signal s2 does not become H at time T3. As a result, neither of the correction currents I1 and I2 flows at time T3.

  In the sampling time from time T3 to time T4, since the output voltage Vd is always smaller than the target voltage, the difference between the integration result of the output voltage Vd and the integration result of the target voltage is a negative value. Therefore, the polarity signal s1, which is a digital signal, remains H at time T4. Further, at time T4, the pulse width control signal s2 becomes H by the width W4 according to the magnitude (absolute value) of the difference between the integration result of the output voltage Vd and the integration result of the target voltage. As a result, the charge of I1 × W4 is supplied to the upper electrode 202a of the curvature sensor 200 at time T4. As a result, the output voltage Vd approaches the target voltage.

  In the sampling time from time T4 to time T5, the difference between the integration result of the output voltage Vd and the integration result of the target voltage is a positive value. Therefore, the polarity signal s1 which is a digital signal is switched to H at time T5. Further, at time T5, the pulse width control signal s2 becomes H by the width W5 according to the magnitude (absolute value) of the difference between the integration result of the output voltage Vd and the integration result of the target voltage. As a result, the charge of I2 × W5 is supplied to the lower electrode 202b of the curvature sensor 200 at time T4. As a result, the output voltage Vd approaches the target voltage.

  As described with reference to FIG. 3, when the amount of change in the output voltage is small, that is, when it is determined by the integration result determination circuit 103 that the output voltage is in a static state, the amount of deviation between the output voltage Vd and the target voltage is determined. By injecting the charge amount into the curvature sensor 200, feedback correction is performed so that the output voltage Vd approaches the target voltage.

  Next, the effect of the present invention will be described using specific examples according to the present application. FIG. 4 is a cross-sectional view showing the structure of the curvature sensor 200 according to the example and the comparative example. The curvature sensor 200 includes carbon electrodes 202 having the same shape on both front and back surfaces of an SPE layer 201 having a length of 20 mm, a width of 20 mm, and a thickness of 0.03 to 0.2 mm. Further, silver paste is applied to the outer surfaces of the two carbon electrodes 202 to form a conductive layer 203. The SPE layer 201, the carbon electrode 202, and the conductive layer 203 are covered with a resin protective film 204. Here, the SPE layer 201 is made of, for example, a known non-aqueous polymer solid electrolyte disclosed in Patent Document 1.

  By connecting the lead 205 to the conductive layer 203, an electromotive force corresponding to the curvature can be measured. In the embodiment, a correction current is supplied from the correction circuit (not shown) to the curvature sensor 200 via the lead 205. Naturally, the curvature sensor 200 according to the comparative example does not include such a correction circuit.

  Further, the curvature sensor 200 is sandwiched between the leaf springs 302. Further, the curvature sensor 200 sandwiched between the leaf springs 302 is fixed to a holder (fixing jig) 302. Here, the positional relationship of each component is as shown in FIG.

  Specifically, the tip of the 20 mm × 20 mm SPE layer 201 and the tip of the leaf spring 302 coincide. Further, it is sandwiched between holders 302 up to the center of the SPE layer 201. That is, the tip side 10 mm of the SPE layer 201 protrudes from the holder 302 and is in a state where it can be bent and deformed. An area of 2 mm from the tip of the SPE layer 201 is pushed by the shaker 301 and bent downward in the drawing.

  Here, the shaker 301 moves in the vertical direction of the drawing indicated by an arrow in FIG. As the shaker 301 moves downward in the drawing, the tip of the SPE layer 201 is pushed and bends and deforms. On the contrary, the bending deformation of the SPE layer 201 is released by moving the shaker 301 upward in the drawing. Further, the displacement at a site 5 mm from the tip of the SPE layer 201 was measured with a laser displacement meter.

  5A and 5B show changes in the output voltage when a bending deformation amount (curvature) that gives an output voltage of about 450 μV is continuously applied. 5A and 5B, the horizontal axis represents time (seconds), and the vertical axis represents output voltage (μV). 5A and 5B show Example A and Comparative Example B. FIG. 5A shows the change in output voltage in a short time. As shown in FIG. 5A, it can be seen that the overshoot at the rise is suppressed in Example A as compared with Comparative Example B.

  FIG. 5B shows the change in output voltage over a long period of time. As shown in FIG. 5B, in Comparative Example B, the output voltage decreases and rises around 0 to 200 seconds, and the output voltage gradually decreases after 1000 seconds. On the other hand, in Example A, the output voltage is held constant around 450 μV.

  Next, FIGS. 6A and 6B show changes in the output voltage when the bending deformation (curvature) at which the output voltage is about 450 μV is applied and then the bending deformation is released. 6A and 6B, the horizontal axis represents time (seconds), and the vertical axis represents output voltage (μV). 6A and 6B, examples A and comparative example B are shown. FIG. 6A shows the output voltage change in a short time. As shown in FIG. 6A, it can be seen that in Example A, compared to Comparative Example B, falling overshoot is suppressed.

  FIG. 6B shows the change in output voltage over a long period of time. As shown in FIG. 6B, in Comparative Example B, the output voltage drops relatively rapidly from 0 μV in the vicinity of 0 to 500 seconds, the output voltage continues to gradually decrease after 1000 seconds, and reaches about −100 μV in 2000 seconds. It has become. In contrast, in Example A, the output voltage is held constant at 0 μV.

  Next, FIGS. 7A and 7B show changes in the output voltage when a bending deformation (curvature) at which the output voltage is about 75 μV is repeatedly applied about every 1 second. The test was performed for 0 to 260 minutes. 7A and 7B, the horizontal axis represents time (seconds), and the vertical axis represents output voltage (μV). 7A and 7B, Example A and Comparative Example B are shown. FIG. 7A shows the change in output voltage from 0 to 20 minutes after the start of the test. As shown in FIG. 7A, in the comparative example B, the maximum value (and the minimum value) of the output voltage gradually decreases. On the other hand, in Example A, the maximum value (and minimum value) of the output voltage is kept constant.

  FIG. 7B shows the change in output voltage at 240 to 260 minutes after the start of the test. As shown in FIG. 7B, in the comparative example B, the maximum value (and the minimum value) of the output voltage further decreases. That is, in the comparative example B, although the applied curvature is the same, the output value of the output voltage is greatly reduced as the number of repetitions is increased. On the other hand, in Example A, the maximum value (and minimum value) of the output voltage hardly changes from that immediately after the start of the test and is kept constant even after 240 minutes have elapsed since the start of the test.

  Next, FIGS. 8A and 8B show changes in the output voltage when a bending deformation (curvature) at which the output voltage is about 250 μV is repeatedly applied every about 2 seconds. 8A and 8B, the horizontal axis represents time (seconds), and the vertical axis represents output voltage (μV). 8A and 8B show Example A and Comparative Example B. FIG. 8A shows the change in output voltage in a short time. As shown in FIG. 8A, in Example A, it can be seen that rising and falling overshoots are suppressed as compared to Comparative Example B.

  FIG. 8B shows the change in output voltage over a long period of time. As shown in FIG. 8B, in the comparative example B, the output voltage gradually decreases with each number of times. On the other hand, in Example A, the output voltage is held constant around 250 μV.

  Next, FIGS. 9A and 9B show changes in the output voltage when the bending deformation amount (curvature) at which the output voltage is about 250 μV is repeatedly given in five steps every about 2 seconds. 9A and 9B, the horizontal axis represents time (seconds), and the vertical axis represents output voltage (μV). 9A and 9B, Example A and Comparative Example B are shown. FIG. 9A shows the change in output voltage in a short time. As shown in FIG. 9A, in Example A, it can be seen that rising and falling overshoots are suppressed compared to Comparative Example B.

  FIG. 9B shows the change in output voltage over a long period of time. As shown in FIG. 9B, in the comparative example B, the output voltage gradually decreases for each number of times. Further, as can be seen from Comparative Example B in FIG. 9B, when bending deformation is applied by dividing into five stages, compared to the case where bending deformation is applied in one stage without being divided as in Comparative Example B of FIG. 9B. The decrease in output voltage is large. On the other hand, in the embodiment A of FIG. 9B, as in the embodiment A of FIG. 9B, the output voltage is held constant at around 250 μV even if the number of repetitions is increased.

  Although the present invention has been described with reference to the exemplary embodiments, the present invention is not limited to the above. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the invention. For example, instead of the integration circuit 102 of FIG. 1, a differentiation circuit may be used for a fairly steep fluctuation, and further, a change in the output voltage may be monitored using both the integration circuit and the differentiation circuit. Further, the integration circuit 102, the integration result determination circuit 103, and the correction current generation circuit 104 are provided in two paths, and the path when the change amount of the output voltage is small and the path when the change amount of the output voltage is large may be separated. .

100 correction circuit 101 conversion circuit 102 integration circuit 103 integration result determination circuit 104 correction current generation circuit 200 curvature sensor 201 SPE layer 202 carbon electrode 202a upper electrode 202b lower electrode 203 conductive layer 204 protective film 205 lead 301 shaker 302 leaf spring 302 holder

Claims (12)

A pair of electrodes;
A sensor comprising a solid polymer electrolyte layer formed between the pair of electrodes,
A correction circuit that corrects an output voltage to be output according to a given curvature,
A monitoring circuit for monitoring the amount of change in the output voltage;
When the amount of change is smaller than a predetermined reference value, it is determined that the sensor is in a stationary state, and a state determination circuit that sets a target voltage;
A correction current generating circuit for injecting an amount of electric charge corresponding to a difference between the output voltage and the target voltage in a direction in which the output voltage approaches the target voltage when it is determined that the sensor is in the stationary state; A sensor output correction circuit. The state determination circuit determines that the sensor is in an operating state when the amount of change is greater than a predetermined reference value.
2. The sensor output correction circuit according to claim 1, wherein, when it is determined that the sensor is in the operation state, the correction current generation circuit injects a charge into the sensor in a direction that reduces the amount of change.   The sensor output correction circuit according to claim 2, wherein when it is determined that the sensor is in the operating state, the amount of the electric charge injected into the sensor is constant regardless of the amount of change.   4. The sensor output correction circuit according to claim 1, wherein when it is determined that the sensor is in a stationary state, the amount of the electric charge injected into the sensor is PWM-controlled. 5. .   The sensor output correction circuit according to claim 1, wherein the monitoring circuit includes an integration circuit.   The sensor output correction circuit according to claim 1, wherein the monitoring circuit includes a differentiation circuit.   The sensor output correction circuit according to claim 1, wherein the solid polymer electrolyte layer is a non-aqueous polymer solid electrolyte layer. A pair of electrodes;
A sensor comprising a solid polymer electrolyte layer formed between the pair of electrodes,
A correction method for correcting an output voltage to be output according to a given curvature,
Monitoring the amount of change in the output voltage;
When the amount of change is smaller than a predetermined reference value, determining that the sensor is stationary and setting a target voltage;
A step of injecting an amount of electric charge corresponding to a difference between the output voltage and the target voltage in a direction in which the output voltage approaches the target voltage when it is determined that the sensor is in a stationary state. Output correction method. Determining that the sensor is in an operating state if the amount of change is greater than a predetermined reference value;
The sensor output correction method according to claim 8, further comprising a step of injecting electric charge in a direction that reduces the amount of change when the sensor is determined to be in the operation state.   The correction method according to claim 9, wherein when it is determined that the operation state is established, the amount of the electric charge injected into the sensor is made constant regardless of the amount of change.   11. The sensor output correction method according to claim 8, wherein when it is determined that the sensor is in a stationary state, the amount of the electric charge injected into the sensor is PWM-controlled.   The sensor output correction method according to claim 8, wherein the solid polymer electrolyte layer is a non-aqueous polymer solid electrolyte layer.