JPH0711532B2 - Angular velocimeter - Google Patents

Description

TECHNICAL FIELD The present invention relates to an angular velocity meter for measuring the angular velocity of a moving body such as an aircraft, a ship, an automobile, etc. inside the moving body.

"Prior art" When the rotational momentum vector when an object is rotated is H, and the input angle measurement vector around an axis perpendicular to this rotation axis is Ω,
A torque vector T = H × Ω represented by the vector product of H and Ω is generated. FIG. 6 shows the positional relationship between these vectors.

FIG. 7 shows a conventional angular velocity meter using this principle. 1 is a motor, 2 is a blade whose one end is fixed to the rotation shaft of the motor 1 and the other end is rotatable about the rotation shaft, 3 is a hinge, 4 is a strain sensitive element, and 5 is attached to the blade 2 to increase angular momentum. The attached weight, 6 is a slip ring, and 7 is an electric wire.
2 ', 3', 4 ', and 5'correspond to 2, 3, 4, and 5, respectively, and are located on the opposite side to the rotation axis.

When there is an angular velocity input as indicated by Ω in the figure, a torque that is a vector product T with the rotational momentum H is generated, and the blade 2
Bends at the hinge 3 as shown by the dotted line. The strain sensitive element 4 is made of a material such as zinc oxide that converts strain into a voltage, and this voltage is guided to the electric wire 7 via a slip ring 6 by a lead wire (not shown).

The blade 2 ′ is provided for balancing with respect to the blade 2, but the output voltage of the strain sensitive element 4 ′ is subjected to reverse strain with respect to the strain sensitive element 4, and thus may be added in mutually opposite phases. In this way, the effect of acceleration is canceled out.

Since the blade 2 is rotating, as shown in FIG. 8, when it comes to θ degrees, only the Y-axis direction component Ω cos θ of Ω is felt and T = H × Ω cos θ, so the output voltage changes in a sinusoidal manner. The output voltage with respect to θ of the strain sensitive element 4 is shown in FIG. Since the phase of this output voltage has the direction information of the angular velocity input in the YZ plane, it can be used as a biaxial angular velocity meter if the output voltage is separated into 90 ° phase-different ones.

[Problems to be Solved by the Invention] As described above, the conventional angular velocity meter uses the slip ring 6, so that it has a short life and it is difficult to obtain a stable rotor.

[Means for Solving the Problems] According to the invention of claim 1, when a rotary shaft, an angular velocity input shaft orthogonal to the rotary shaft, and an output torque shaft orthogonal to these shafts are defined in the frame body that moves together with the moving body. , One end is fixed to the rotary shaft, the other end rotates around the rotary shaft, and a blade with a weight for increasing angular momentum is provided, and it deforms when a torque around the output torque axis is applied to the blade. A hinge is provided, the blade rotates, and when the direction connecting the one end and the other end of the blade coincides with the angular velocity input shaft, an optical micro displacement measurement system is provided to measure the deformation of the blade. The measuring system is composed of a set of a projector and a light receiving element provided on the frame body and a mirror provided on the blade, and the angular velocity is measured by measuring the deformation of the blade when the angular velocity is input.

According to a second aspect of the present invention, in the first aspect of the present invention, a pair of blades provided with a weight and a hinge are provided so as to be positioned on the same straight line with the rotation axis sandwiched therebetween, and the pair of optical micro-displacement measurement systems rotate. They are provided on opposite sides of the axis, and the differential outputs of both of these optical micro displacement measurement systems are taken out.

[Embodiment] FIG. 1 shows an embodiment of the present invention, 1 is a motor, 2 is a blade, 3 is a hinge, 5 is a weight, 11 is a mirror provided on the tip surface of the blade 2, 12 is a projector, Reference numeral 13 is a light receiving element. The projector 12 and the light receiving element 13 project light onto the mirror 11 and receive the reflected light when the direction connecting one end and the other end fixed to the rotating shaft of the blade 2 coincides with the angular velocity input shaft. Placed in a position. 2 ', 3', 5 ', 11', 1
Reference numerals 2 ', 13' correspond to 2, 3, 5, 11, 12, 13 respectively, and the blades 2 and 2'are positioned on the same straight line with the rotary shaft of the motor 1 interposed therebetween, and the projector 12 The light receiving element 13, the projector 12 ', and the light receiving element 13' are located on opposite sides of the rotation axis. In addition, these are arranged in a frame (not shown) to form an angular velocity meter.

As in the case of FIG. 7, when there is an angular velocity input Ω, a torque T is generated, the hinges 3 and 3 ′ bend, and the blades 2 and 2 ′ move to the 7th position.
It is modified as in the case of the figure. The light projector 12, the light receiving element 13, and the mirror 11 constitute an optical minute displacement measuring system as shown in FIG. Although this optical micro displacement measuring system is well known, it will not be described in detail, but in FIG. 2, the parallel light beam from the light projector 12 strikes the mirror 11 and is reflected by the light receiving elements 13a and 13b. The light receiving element 13 is formed by connecting the same two divided parts 13a and 13b so that the outputs are reversed, and each light receiving element outputs an output in proportion to the area on which the parallel beam hits. Therefore, when the mirror 11 is in the position shown by the solid line, the combined output of the light receiving elements 13a and 13b is 0, but when the mirror 11 is tilted as shown by the dotted line, an output is output. This output is proportional to α in the minute range of the inclination angle α.

In the case of FIG. 1 as well, as in the case of FIG.
Is rotated, and the outputs of the light receiving elements 13 and 13 'are as shown in FIG. Here, θ is the same as that shown in FIG.
The voltage at the output of the light receiving element 13 when θ = 180 ° is the mirror 11 ′.
Is when the light source 12 and the light receiving element 13 arrive. The same applies to the output of the light receiving element 13 '.

Since the outputs of the light receiving elements 13 and 13 'have the same magnitude and opposite polarities, if they are taken out as a differential output, the output voltage is 2
Double. In addition, the influence of acceleration can be canceled. If there is no angular velocity input in Fig. 4 and acceleration is applied in the X direction, the hinges 3 and 3'are deformed as shown by the dotted lines in Fig. 4, so that the voltages of the light receiving elements 13 and 13 'become in phase and cancel. Fit.

Also, as shown by the dotted line in FIG. 4, when the blades 2, 2'rotate to the Z-axis position, the optical micro-displacement measuring system 12 ", 13", 12, such that they are reflected by the mirrors 11, 11 '. If 13 is attached, the output of the light receiving elements 13 ″, 13 indicates the angular velocity around the Z axis, and it is used as a biaxial angular velocity meter.

FIG. 5 shows another embodiment of the present invention. In the embodiment shown in FIG. 1, the output voltage is pulsed as shown in FIG.
Although it is easily affected by noise and the like, the disc 10 shown in FIG. 5 rotates the disc 10 by the motor 1. A large number of blades 2 are formed by forming radial grooves on the disc 10. Each blade 2 has a hinge 3 and a mirror 11, and operates similarly to the case of FIG. Since there are many blades 2 in this example,
The output is cut off only in the groove portion of the cut, but an almost continuous output voltage is obtained.

[Advantages of the Invention] As described above, the angular velocity meter of the present invention does not require a slip ring, has a long life, and does not measure the angular velocity around two axes by phase detection like the conventional one, but an optical minute Since the output of the displacement measuring system itself indicates the angular velocity around each axis, the electric circuit is simple and the phase reference detector is not necessary. Furthermore, there is a feature that errors due to acceleration are canceled.

[Brief description of drawings]

1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a view showing an optical micro displacement measuring system, FIG. 3 is an output characteristic diagram of FIG. 1, and FIG. 4 is a state in which acceleration is applied. FIG. 5, FIG. 5 is a perspective view showing another embodiment of the present invention, FIG. 6 is a view showing the relationship between the rotational momentum vector H, the input angular velocity vector Ω and the torque vector T, and FIG. FIG. 8 is a perspective view showing the angular velocity meter, FIG. 8 is a view showing a state in which the blade is rotated at a position of θ degrees, and FIG. 9 is an output characteristic view.

Claims (2)

[Claims] 1. When a rotary shaft, an angular velocity input shaft orthogonal thereto and an output torque shaft orthogonal to these shafts are defined on a frame body which moves together with a movable body, one end is fixed to the rotary shaft and the other end is fixed. Rotating around the rotation axis, and provided with a blade with a weight for increasing angular momentum, the blade is provided with a hinge that deforms when a torque around the output torque axis is applied, and the blade rotates. When the direction connecting the one end and the other end of the blade coincides with the angular velocity input shaft, an optical micro displacement measurement system for measuring the deformation of the blade is provided, and the optical micro displacement measurement system is the frame. An angular velocity meter comprising a set of a projector and a light receiving element provided on the body and a mirror provided on the blade, and measuring the angular velocity by measuring the deformation of the blade when the angular velocity is input. 2. A pair of the blades provided with the weight and the hinge are provided on the same straight line with the rotary shaft interposed therebetween, and a pair of the optical micro-displacement measuring system is provided with respect to the rotary shaft. 2. The angular velocimeter according to claim 1, wherein the angular velocimeters are provided on opposite sides of each other and take out a differential output of both of these optical minute displacement measuring systems.