JP5212944B2 - Force sensor and force sensing system - Google Patents

Description

  The present invention relates to a force sensor and a force sensing system, and more particularly to a force sensor and a force sensing system using a reflection type distance sensor such as a photo reflector or an ultrasonic sensor.

The present inventors have already proposed a tracheal intubation training apparatus for evaluating a tracheal intubation technique performed by a doctor, a paramedic, or the like (Patent Document 1). A force sensor 50 shown in FIG. 8 is used in the tracheal intubation training apparatus. The force sensor 50 includes a base 51, a photo reflector 55 that is fixed on the base 51 and includes a light emitting element 53 and a light receiving element 54, an elastic member 57 such as a sponge that covers the periphery of the photo reflector 55, and an elastic member. A light-shielding reflecting plate 59 fixed to the upper surface of the member 57 and an optical space 60 surrounded by the base 51, the elastic member 57 and the reflecting plate 59 and in which light emitted from the light emitting element 53 propagates. . The force sensor 50 described above detects the magnitude of the external force based on the following principle. That is, the light emitted from the light emitting element 53 to the light space 60 is reflected by the inner surface of the reflecting plate 59 and detected by the light receiving element 54, but when an external force is applied to the contact surface 59A that is the upper surface of the reflecting plate 59, The elastic member 57 is deformed according to the magnitude of the external force, the shape (volume) of the light space 60 is changed, the reflection distance from the reflection plate 59 to the photo reflector 55 is changed, and the amount of light detected by the light receiving element 54 is changed. change. Accordingly, the current from the light receiving element 54 changes due to the deformation of the elastic member 57 due to the addition of an external force to the contact surface 59A. By measuring the voltage change due to the change in the current, the contact surface 59A is added. External force can be detected. Here, in general, the photo reflector 55 has the output characteristics shown in FIG. 9, and according to the output characteristics, the voltage with respect to the reflection distance of light that is the separation distance between the photo reflector 55 and the reflection plate 59. The relationship between values is non-linear overall. However, like the range of the reflection distances D _{1 to} D ₂ in FIG. 9, there is a reflection distance range in which the relationship between the reflection distance and the voltage value can be approximated linearly. Thus, for example, the reflection distance of the initial state where an external force to the reflection plate 59 does not act when the D _1, if the tensile force upward in FIG. 8 is applied to the reflection plate 59, reflection distance D ₂ Until then, the reflection distance and the voltage value which increase in accordance with the magnitude of the applied tensile force are substantially proportional. Therefore, between the reflection distances D _{1 and} D ₂ , the measured voltage value and the magnitude of the applied external force are in a substantially proportional relationship, and the measurement was performed by storing the proportional coefficient in a measurement device (not shown). The magnitude of the external force acting on the force sensor 50 can be obtained from the voltage value.

JP 2008-64824 A

However, in the force sensor 50, the characteristics of the photo-reflector 55, the reflected distance exceeds D _2, no longer possible to accurately measure the magnitude of the external force. That is, the reflected distance is more than D _2, since not be linearly approximated, not use the proportional relationship between the size of the voltage value and the external force described above, not simply asked the magnitude of the external force from the measured voltage value. Furthermore, not only the measured voltage value itself becomes small, but also the rate of change in voltage with respect to the rate of change in reflection distance becomes gradually smaller, and considering the voltage measurement error, etc., accurate measurement of the magnitude of the external force becomes impossible. End up. Therefore, in the force sensor 50 using the photo reflector 55 having the output characteristics of FIG. 9, it can be used only for the displacement of the reflection plate 59 within the linear approximation range of the reflection distances D _{1 to} D ₂ , and the reflection distance D _2. If it is assumed that an external force exceeding ₁ is applied, the force sensor 50 must be replaced with another photo reflector 55 having a different reflection distance D ₁ -D ₂ range. Further, even if an external force that causes the reflecting plate 59 to be displaced within the range of the reflection distances D _{1 to} D ₂ is applied, if the reflecting plate 59 is displaced within a minute range within the range, the voltage changes. In this case as well, there is a possibility that the magnitude of the external force cannot be measured accurately considering the voltage measurement error and the like. Therefore, in such a case, it is necessary to replace the force sensor 50 with the highly sensitive photoreflector 55 having a narrow width in the range of the reflection distances D _{1 to} D ₂ . As described above, the structure of the force sensor 50 uses the photo reflector 55 that can use the relationship between the reflection distance and the voltage value only in a part of the range due to the output characteristics. I can't. For this reason, it is necessary to select an appropriate force sensor 50 according to the magnitude of the external force to be measured from among a variety of force sensors 50 having different sensitivities of the photo reflector 55, and each time an external force measurement target is selected. There is a problem that it takes time and effort to replace the force sensor 50 once attached to the site. This problem can be solved by using a high-performance force sensor that can measure the magnitude of the external force over a wide range and with high accuracy. However, the force sensor is more than the above-described force sensor 50 using the inexpensive photo reflector 55. It will be far more expensive, leading to an increase in the manufacturing cost of the tracheal intubation training apparatus to be attached.

  The present invention has been devised by paying attention to such a problem, and its purpose is to easily adjust measurement sensitivity while using an inexpensive force detection means such as a photoreflector. An object of the present invention is to provide a force sensor and a force sensing system that can eliminate the need for replacement according to the magnitude of an external force.

In order to achieve the above object, the present invention provides a force sensor that generates an electrical signal in accordance with the magnitude of an applied external force.
At least one of the pair of rod-shaped bodies arranged relative to each other, a support body that supports each rod-shaped body so that one end side of each rod-shaped body is a free end side and the other end side is a fixed end side, and Attached to the force input portion to which the external force acts and either one of the rod-like bodies, and emits light or ultrasonic waves toward the other rod-like body and reflected by the other rod-like body Force detecting means for generating an electric signal corresponding to the magnitude of the light or ultrasonic wave,
The force input unit and / or the force detection means are configured to be provided so that the attachment position can be adjusted along the extending direction of the rod-shaped body.

  A first distance measuring unit that generates an electrical signal in accordance with a first separation distance from the support to the force input unit; and a second separation from the support to the force detection unit. In addition, a configuration in which a second distance measuring unit that generates an electrical signal is further provided can be employed.

Furthermore, the present invention is a force sensing system comprising: the force sensor according to claim 1; and an external force calculation device that obtains the magnitude of the external force from an electrical signal from the force sensor,
The external force calculation device includes a distance input unit for inputting a first separation distance from the support to the force input unit and a second separation distance from the support to the force detection unit, and the distance input. A force calculation unit that calculates the magnitude of the external force by substituting the first and second separation distances input by the unit and the magnitude of the electric signal from the force detection unit into a previously stored calculation formula It has a configuration that comprises.

Further, the present invention is a force sensing system comprising: the force sensor according to claim 2; and an external force calculation device that obtains the magnitude of the external force by an electric signal from the force sensor.
The external force calculation device includes a distance calculation unit that determines the first and second separation distances based on electrical signals from the first and second distance measurement means, and the first and second distances calculated by the distance calculation unit. 2 and a force calculation unit for calculating the magnitude of the external force by substituting the distance of 2 and the magnitude of the electric signal from the force detection means into a previously stored calculation formula. .

  In the present invention, the attachment position of the force input part and / or the force detection means can be adjusted along the extending direction of the rod-shaped body in which one end side is the free end side and the other end side is the fixed end side. By adjusting the position, the amount of displacement of the force detection means changes even if the applied external force has the same magnitude. Therefore, by adjusting the position of the force input unit and / or the force detection means according to the magnitude of the external force assumed in advance, the distance between the force detection means and the rod-like body is maintained regardless of the magnitude of the external force. A linear approximation range in the relationship between a certain reflection distance and an electric signal can be used. In addition, for example, even when a minute external force acts on the force input unit, the difference in electrical signal generated before and after the force action can be amplified by increasing the reflection distance by the position adjustment. Therefore, according to the present invention, even if an inexpensive reflective distance sensor such as a photoreflector such as a photoreflector that can be linearly approximated in a partial region, although the relationship between the reflection distance and the output value is entirely nonlinear, it can be of any magnitude. It is possible to cope with the measurement of the external force and easily adjust the sensitivity in the measurement.

1 is a block diagram illustrating a schematic configuration of a force sensing system according to a first embodiment. The schematic perspective view of the force sensor applied to the force sensing system which concerns on 1st Embodiment. The schematic sectional drawing which follows the AA line of FIG. The block diagram showing the schematic structure of the force sensing system which concerns on 2nd Embodiment. The schematic perspective view of the force sensor applied to the force sensing system which concerns on 2nd Embodiment. FIG. 6 is a schematic sectional view taken along line AA in FIG. 5. The schematic side view of the torque sensor which concerns on a modification. The schematic sectional drawing of the force sensor in a prior art example. A graph showing the general characteristics of a photo reflector.

(First embodiment)
FIG. 1 is a block diagram showing the configuration of the force sensing system according to the first embodiment of the present invention. In this figure, the force sensing system 10 includes a force sensor 11 that generates an electrical signal according to the magnitude of an applied external force, and the magnitude of the external force that has acted on the force sensor 11 based on the electrical signal from the force sensor 11. And an external force calculation device 12 for obtaining the above. The force sensing system 10 according to the present embodiment is not particularly limited, but is applied to a tracheal intubation training apparatus (not shown) for evaluating a tracheal intubation technique performed by a doctor, an emergency medical technician, or the like.

  As shown in FIGS. 2 and 3, the force sensor 11 includes a pair of first and second rod-like bodies 14 and 15 made of square members that are relatively arranged in the vertical direction in the figures, and the rod-like bodies 14. , 15 are attached to the support body 17 for supporting the rod-like bodies 14, 15 and the first and second rod-like bodies 14, 15 so that one end side is a free end side and the other end side is a fixed end side. 2 is attached to the force input portion 19 acting on the first rod-like body 14 located on the upper side in FIG. 2, and generates an electric signal according to the displacement of the rod-like bodies 14 and 15 due to the external force acting on the force input portion 19. The force detection means 21 is provided.

  The first rod-like body 14 is formed with a fixed end side region 25 having screw holes 23 formed at a plurality of locations along the extending direction, and a slit 27 that is open at the front end side and penetrates in both the upper and lower sides. It consists of a bifurcated free end region 28.

  The second rod-shaped body 15 has a fixed end side region 31 having screw holes 30 formed at positions facing the respective screw holes 23 of the first rod-shaped body 14, and an upper surface portion facing the slit 27. It comprises a free end side region 33 provided with a reflecting material 32. As will be described later, the reflector 32 is formed of a material or color that can reflect the light emitted from the force detector 21 toward the force detector 21. In addition, if the upper surface part of the free end side area | region 33 is formed with the material and color which can reflect light, it is not necessary to provide the reflecting material 32. FIG.

  The support body 17 is fixed to a part of the tracheal intubation training apparatus (not shown) so as not to be displaced even when an external force is applied to the force input unit 19. The support 17 includes an upper portion 35 positioned on the upper side in FIG. 2 with respect to the portion where the first rod-shaped body 14 continues, and a lower side positioned on the lower side in FIG. 2 with respect to the portion where the second rod-shaped body 15 continues. It consists of a part 36 and an intermediate part 37 located between the upper part 35 and the lower part 36.

  The force input portion 19 includes a connecting member 38 that can be screwed into and attached to the screw holes 23 and 30 formed in the first and second rod-like bodies 14 and 15. A wire W on which tension is applied in the tracheal intubation training apparatus (not shown) is fixed to the connecting member 38, whereby the external force acting on the force input unit 38 becomes the tension of the wire W, and the force sensor 11 functions as a tensile force measurement sensor. Further, the attachment position of the connecting member 38 with respect to the first and second rod-like bodies 14 and 15 can be changed by appropriately changing the screw holes 23 and 30 into which the connecting member 38 is inserted. Adjustment is possible along the exit direction. At this time, the connecting members 38 and 38 attached to the first and second rod-like bodies 14 and 15 are screw holes 23 and 30 at opposite positions so that the distance from the support 17 is the same. Attached to.

  The force detection means 21 includes a photo reflector 39 disposed in the slit 27 and connected to the external force calculation device 12 (see FIG. 1), and a slide member 40 that supports the photo reflector 39 from above.

  Although not shown, the photo reflector 39 includes a light emitting element that emits infrared light and a light receiving element that receives infrared light, and generates a current according to the amount of light detected by the light receiving element. The current is detected by the external force calculation device 12. That is, the light irradiated from the photo reflector 39 toward the reflecting material 32 of the second rod-shaped body 15 is reflected by the reflecting material 32 and detected by the photo reflector 39. Here, when an external force is applied to the force input unit 19, the free end side regions 28 and 33 of the rod-like bodies 14 and 15 are bent and deformed in the vertical direction, and depending on the magnitude of the applied external force, The reflection distance, which is the separation distance from the photo reflector 39, changes, and the amount of light received by the photo reflector 39 changes according to the change. Therefore, the magnitude of the external force can be obtained by measuring the voltage change based on the current change corresponding to the received light amount. Although not particularly limited, as shown in FIG. 3, the photo reflector 39 is disposed at a height at which the lower surface portion that emits and receives light is about half the thickness of the first rod-like body 14. Is done.

  Instead of the photo reflector 39, an ultrasonic sensor that emits an ultrasonic wave and receives an ultrasonic wave reflected by the second rod 15 and converts it into an electric signal can be used. In short, here, a reflection-type distance sensor that emits light or ultrasonic waves toward the second rod-shaped body 15 and generates an electrical signal corresponding to the magnitude of the light or ultrasonic waves reflected by the second rod-shaped body 15. Anything is fine.

  The slide member 40 is placed on the upper surface of the free end side region 28 across the slit 27 and is movable along the slit 27. Therefore, the position of the photo reflector 39 supported by the slide member 40 can be changed along the extending direction of the first rod-like body 14, and accordingly, the light emission of the photo reflector 39 along the extending direction. In addition, the light receiving position can be adjusted. In addition, after such position adjustment is made, the slide member 40 is fixed to the first rod-like body 14 so as to be immovable by fixing means such as a screw (not shown).

  The external force calculation device 12 is configured by a computer including a calculation processing device such as a CPU and a storage device such as a memory and a hard disk, and a distance input unit to which predetermined distance information is input as shown in FIG. 41 and a force calculation unit 42 for obtaining the magnitude of the external force applied to the force input unit 19 based on the distance information input by the distance input unit 41 and the current state from the photo reflector 39. .

  A first separation distance from the support 17 to the connecting member 38 and a second separation distance from the support 17 to the photo reflector 39 are input to the distance input unit 41. Here, for example, the position of the screw holes 23 and 30 into which the connecting member 38 is inserted, for example, what number of screw holes 23 and 30 are inserted from the support 17 side, and the like are input to the distance input unit 41. . Then, the first separation distance at this time is obtained from the relationship between the positions of the screw holes 23 and 30 stored in the memory (not shown) and the first separation distance. Similarly, the second separation distance is also obtained by inputting the position of the fixing means (not shown) that fixes the slide member 40. Note that a scale or the like may be provided on the side surface of the first rod-like body 14, and values actually measured by the user using the scale may be input to the distance input unit 41 as the first and second separation distances.

  The force calculation unit 42 obtains an external force applied to the force input unit 19 using the function of measuring the voltage value related to the current from the photo reflector 39 and the voltage value and the first and second separation distances as parameters. By substituting the function for storing the arithmetic expression, the measured voltage value and the first and second separation distances from the distance input unit 41 into the arithmetic expression, an external force acting on the force input unit 19, that is, the wire W And a function for obtaining the tension of the.

  The arithmetic expression is expressed by the following expression obtained from the characteristics of the photo reflector 19 and the material dynamics calculation of the cantilever.

F = (AV + B) / (− L ₁ ³ + 2L ₂ ³ + 3L ₁ ² L ₂ −6L ₁ L ₂ ² )

Here, “F” is the magnitude of the external force to be obtained, “L ₁ ” is the first separation distance sent from the distance input unit 41, and “L ₂ ” is sent from the distance input unit 41. Is the second separated distance. “V” is a voltage value measured based on the current generated from the photo reflector 39. Furthermore, “A” and “B” are constants determined according to the characteristics of the photo reflector 39 and the material of the rod-like bodies 14 and 15. Specifically, the constant A is the slope of the approximate straight line of the effective area that can be linearly approximated in the output characteristic diagram of the photoreflector 39 (for example, see FIG. 9), the longitudinal elastic modulus of the rod-like bodies 14 and 15, and the secondary cross section. Determined from the moment. The constant B is the vertical direction of the first and second rod-like bodies 14 and 15 in the initial state in which the linear equation of the approximate curve, the longitudinal elastic modulus and the secondary moment of section, and the external force are not applied. It is determined from the separation width. This separation width is set to be the minimum value D ₁ of the reflection distances D _{1 to} D ₂ in FIG.

  In the force sensing system 10 described above, the force input unit 19 or the force detection unit 21 is positioned as follows, and the first and second rod-like bodies 14 and 15 are moved up and down from the wire W through the force input unit 19. The tensile force separating in the direction is measured.

First, from the assumed value of the tensile force acting on the force input portion 19, the distance between the reflector 32 and the photo reflector 39 (reflector distance), reflecting the distance D ₁ to D 9 as the effective area of the photo-reflector 39 _When it seems that it will become larger than the range of ₂ , the force input part 19 or the force detection means 21 is changed closer to the support body 17 from the present attachment position. As a result, even if the tensile force applied to the force input unit 19 is the same before and after the change, the separation distance between the reflector 32 and the photo reflector 39 is reduced from that before the change due to the nature of the cantilever. It becomes possible to be within the range of the distances D _{1 to} D ₂ , and it becomes possible to measure the tensile force that was conventionally impossible to measure with the same photo reflector 39. Incidentally, when the voltage value associated with the current from the photo reflector 39 is measured equal to or less than the predetermined value, it is determined that the reflection distance is greater than the D _2, the warning or display or the like, the force input portion 19 or It is also possible to provide the force calculation unit 42 with a function that prompts the user to change the attachment position of the force detection means 21.

  Also, for example, when the assumed tensile force is small, the change in the reflection distance before and after the action of the tensile force becomes minute, and the amount of change in the voltage value associated therewith becomes a minute value corresponding to the measurement error. Changes the force input unit 19 or the force detection means 21 closer to the tip than the current attachment position. As a result, even if the tensile force acting on the force input unit 19 is the same before and after the change, the separation distance between the reflector 32 and the photo reflector 39 is increased from before the change, and the voltage value before and after the action of the tensile force is increased. Can be substantially amplified, and the sensitivity of the force sensor 11 is increased.

  Therefore, according to such a first embodiment, by adjusting the positions of the force input unit 19 and the force detection means 21 according to the assumed external force, from the mechanical properties of the cantilever, Regardless of the magnitude of the external force, the effective area that can be linearly approximated in the output characteristic diagram of the photoreflector 39 can always be used, and the sensitivity of the force sensor 11 can be easily adjusted. As a result, there is an effect that it is not necessary to replace the force sensor 11 attached to the tracheal intubation training device with another force sensor 11 having different output characteristics according to the assumed external force.

  Next, another embodiment of the present invention will be described. In the following description, the same reference numerals are used for the same or equivalent components as in the first embodiment, and the description is omitted or simplified.

(Second Embodiment)
In the present embodiment, the first separation distance from the support 17 to the force input unit 19 and the second separation distance from the support 17 to the force detection means 21 are automatically measured, and the measurement result is used. The feature is that the magnitude of the external force is obtained. That is, in the present embodiment, as shown in FIGS. 4 to 6, the force sensor 11 is a first distance measurement that generates an electrical signal according to the first separation distance with respect to the first embodiment. Means 43 and second distance measuring means 44 for generating an electrical signal according to the second separation distance are further provided. Further, the external force calculation device 12 calculates the first and second separation distances based on electric signals from the first and second distance measuring means 43 and 44 instead of the distance input unit 41 of the first embodiment. A distance calculation unit 45 to be obtained is newly provided. Other configurations are substantially the same as those of the first embodiment.

  As shown in FIGS. 5 and 6, the first distance measuring means 43 is fixed to the upper portion 35 of the support body 17 and can emit light toward the force input portion 19. It consists of a first reflector 47 that is connected to the upper end side of the connecting member 38 attached to the rod-like body 14 and is provided so as to be able to reflect light from the photo reflector 46. According to this configuration, light from a light emitting element (not shown) of the photo reflector 46 is reflected by the first reflecting plate 47 and received by a light receiving element (not shown) of the photo reflector 46. It will change according to the 1st separation distance between 46 and the 1st reflecting plate 47. FIG. Then, the current generated by the photo reflector 46 is sent to the distance calculation unit 45 of the external force calculation device 12.

  The second distance measuring means 44 includes a photo reflector 48 that is fixed to the intermediate portion 37 of the support 17 and can emit light toward the bending space S between the first and second rod-like bodies 14 and 15, and a slide. The second reflector 49 includes a second reflector 49 that extends from the lower surface of the member 40 through the slit 27 to the bending space S and is capable of reflecting light from the photo reflector 48. Therefore, on the same principle as the photo reflector 46 of the first distance measuring means 43, the amount of light received by the photo reflector 48 changes according to the second separation distance between the photo reflector 48 and the second reflector 49. Therefore, the current here is also sent to the distance calculation unit 45 of the external force calculation device 12.

  The distance calculator 45 measures a voltage value based on the current generated from the photo reflectors 46 and 48, and obtains a separation distance corresponding to the measured voltage value based on the output characteristics of the photo reflectors 46 and 48 stored in advance. It is like that. As the photo reflector 46 for measuring the first separation distance, a photoreflector having a characteristic in which the first separation distance is within the effective area in the output characteristic diagram is adopted. Similarly, the second separation distance is used. As the photo reflector 48 that measures the above, a photoreflector 48 having a characteristic in which the range of the second separation distance falls within the effective area is employed.

  In the force calculation unit 42, the voltage value associated with the current generated by the photo reflector 39 of the force detection means 21 and the first and second separation distances from the distance calculation unit 45 are the same calculation as in the first embodiment. By substituting into the equation, an external force acting on the force input unit 19 is obtained.

  Therefore, according to the second embodiment, the same effects as those of the first embodiment can be obtained, and when the mounting positions of the force input unit 19 and the force detection means 21 are changed, the first and second It is possible to save the trouble of measuring and inputting the separation distance.

  Note that the force input unit 19 is not necessarily provided on both the first and second rod-like bodies 14 and 15, and is provided on at least one of the first and second rod-like bodies 14 and 15 according to the external force input state. It can also be provided.

  In addition, the configuration of the free end side regions 28 and 33 in the first and second rod-like bodies 14 and 15 may be reversed from the above-described embodiments. That is, the reflective material 32 may be provided on the first rod-like body 14, and the force detecting means 21 and the slit 27 may be provided on the second rod-like body 15.

  Furthermore, in each said embodiment, although both the force input part 19 and the force detection means 21 can adjust an attachment position along the extension direction of the 1st rod-shaped body 14, although the said attachment position The adjustment only needs to be enabled by at least one of the force input unit 19 and the force detection means 21.

  Further, the shape of the force sensor 11 is not limited to the shape of each of the above-described embodiments, and the upper portion 35 and the lower portion 36 of the support 17 are omitted, and only the intermediate portion 37 is left in a substantially U shape. It is also possible to adopt a substantially U-shaped one in a side view in which the intermediate portion 37 is curved so as to protrude to the opposite side of the rod-like bodies 14 and 15.

  Furthermore, the force sensor 11 of the present invention can be used as a compressive force measuring sensor, a torque sensor, and a bending moment sensor based on the same principle as described above. As shown in FIG. 7, the torque sensor has a structure in which the first and second arms A1 and A2 are fixed to the connecting members 38 and 38 attached to the first and second rod-like bodies 14 and 15, respectively. Can be illustrated. The first and second arms A1 and A2 are mutually connected at one end side by a shaft member C, and when torque acts on the shaft member C, the first and second arms A1 and A2 rotate with each other using the shaft member C as a rotation fulcrum. When the rotation occurs, the first and second rod-like bodies 14 and 15 move closer to each other according to the magnitude of the torque, and the magnitude of the torque can be obtained by the same procedure as in each of the embodiments. it can.

  In addition, the configuration of each part of the apparatus in the present invention is not limited to the illustrated configuration example, and various modifications are possible as long as substantially the same operation is achieved.

DESCRIPTION OF SYMBOLS 10 Force sensing system 11 Force sensor 12 External force calculating device 14 1st rod-shaped body 15 2nd rod-shaped body 17 Support body 19 Force input part 21 Force detection means 41 Distance input part 42 Force calculation part 43 1st distance measurement means 44 First distance measuring means 45 Distance calculation unit

Claims (2)

In a force sensor that generates an electrical signal according to the magnitude of the applied external force,
At least one of the pair of rod-shaped bodies arranged relative to each other, a support body that supports each rod-shaped body so that one end side of each rod-shaped body is a free end side and the other end side is a fixed end side, and Attached to the force input portion to which the external force acts and either one of the rod-like bodies, and emits light or ultrasonic waves toward the other rod-like body and reflected by the other rod-like body Force detecting means for generating an electric signal corresponding to the magnitude of the light or ultrasonic wave, and first distance measuring means for generating an electric signal according to a first separation distance from the support to the force input portion. And second distance measuring means for generating an electrical signal in accordance with a second separation distance from the support to the force detecting means ,
The force sensor, wherein the force input unit and / or the force detection means are provided so that an attachment position can be adjusted along the extending direction of the rod-shaped body. A force sensing system comprising: the force sensor according to claim 1; and an external force calculation device that obtains the magnitude of the external force from an electric signal from the force sensor,
The external force calculation device includes a distance calculation unit that determines the first and second separation distances based on electrical signals from the first and second distance measurement means, and the first and second distances calculated by the distance calculation unit. A force calculating unit that calculates the magnitude of the external force by substituting the distance of 2 and the magnitude of the electrical signal from the force detecting means into a previously stored calculation formula. Sensing system.

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