JPS6186613A - Apparatus for computing turning angle in space - Google Patents

Abstract

PURPOSE:To measure the turning angle in a space when a human body and the like are in the moving state, by using a light, compact inertialbody supporting type measuring instrument, using a dynamic-torque balancing method in measurement, processing the output by using a computer using ICs, and computing the turning angle. CONSTITUTION:A pair of inertial cut wheels 13a and 13b, whose weights are balanced, are attached to one end of a pointer 2, which is connected to a movable coil 1. Inertial moment in a movable part (u) is increased. With the inertial torque when a moving body is turned as input torque, the torque is imparted to the movable part (u) including a the movable coil 1. The displacement of the other tip of the pointer 2 from the zero position is detected by a detecting part (d). The displacement is converted into an electric signal. The signal is amplified by a amplifier part (a) and outputted to an output terminal 8. The output of the output terminal 8 is negatively fed back to the coil 1 through a feedback circuit (f). The output at the output terminal 8, which is obtained by applying the difference between the input torque and the torque caused by the feedback current to the coil 1, is integrated twice by a computer, and the turning angle of the moving body in the space during the movement can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for calculating a spatial rotation angle on a rotating body.

[Problems with conventional technology]

Measuring the spatial rotation angle of a moving body rotating in space using an inertial force measuring device generally requires a large-scale measurement system such as a gyro device, an accelerometer, or a combination thereof. These devices are often used for motion analysis or navigation measurement of large moving objects such as ships, airplanes, and flying objects, and small devices that can be attached to human limbs or manipulators for human body motion analysis or running robot control, etc. However, until now there has been no transducer system that can accurately measure spatial rotational motion.

Therefore, an object of the present invention is to provide a practical device that can be easily attached to a human body or a manipulator to easily measure the spatial rotation angle in a state of movement. The present invention uses a very light and small inertial support type measuring device, and uses a dynamic torque balance method for its measurement method.
In addition, the output values from the measuring instruments are miniaturized and integrated and processed at high speed by an l-computer to calculate the rotation angle.

The inertial support type measuring instrument used in the present invention requires a movable part that is small and light in shape and has a small driving force. An inertial force measuring device is used by adding parts with the necessary functions to a simple small DC ammeter component. Then, a pair of large inertia wheels whose weight is balanced is attached to one end of the pointer of this ammeter type movable part to increase the moment of inertia of the movable part, and detect the inertial force torque acting on it during movement. By integrating twice the output of the dynamic torque measuring device, which is configured to amplify and output the current to the outside and also feed negative current back to the coil via a feedback circuit that operates proportionally, the spatial rotation of the moving body is calculated. Now calculates the moving angle. Hereinafter, the present invention will be specifically explained with reference to illustrated embodiments.

〔Example〕

FIG. 1(a) is a configuration diagram showing an example of a measuring instrument used in the present invention. The measuring instrument shown in the figure is composed of a main body U having a movable part, a detection part d1, an amplification part a, and a feedback circuit f. In the main body U, MG is a permanent magnet, SY is a sublayer iron plate yoke, and SF
indicates a soft iron core, and a moving coil (1) supported on the axis O is housed in the gap between SY and SF. Further, a pointer (2) is coupled to the moving coil (1). This inertial force measuring device with an ammeter type movable part is attached to a rotating or rotating body.

FIG. 1(b) is a perspective view showing the relationship between the mounting and posture. In this figure, the spatial coordinate system is o-xyz, and the coordinates of the moving body are 〇-ξη. ξ0η is in the spatial XOY plane). On the other hand, the main body U of the measuring instrument placed on this moving body has its axis passing through the coil axis O aligned with the moving body 0ζ axis, and the direction of the pointer (2) aligned with the direction of the Oη force that crosses the axis 0. Attached to the moving body.

Again in Figure 1 (a), the coil (1) of the pointer (2)
A pair of large inertia wheels (13m) with weight balanced at the side ends,
(13b) is attached to increase the moment of inertia of the movable part including the coil (1), so that inertia torque is applied to the movable part as input torque when the moving body rotates. In addition, pairs of light emitting elements and light receiving elements (5,) are attached to the measuring instrument fixing parts (41) and (4□), with a small interval between both sides (31) and (3□) of the pointer (2). −(61) and (5□
)-(62) are provided. Each light emitting element (5,) + (5
2) Light emission from both sides of the corresponding pointer (3,),
(32) and is reflected by the light receiving elements (6,), (6
2). In addition, at the zero (equilibrium) position where the Oη force direction of the pointer (2) coincides, the small intervals on both sides are set to the same amount, and when the moving body rotates, the movable coil (
The input torque T1 to the movable part including 1) and the movable coil (1
) is the difference torque (
TI - Tf) is applied to the measuring instrument moving part. As a result, the small spacing between the photodetectors changes, and correspondingly, the detection currents of both the resistors r4. The differential output from r2 is amplified and taken out from the output terminal (8), and at the same time is negatively fed back to the movable coil (1) via the feedback circuit f. Note that the detection section d does not necessarily have to be based on light.

FIG. 2 is a block diagram for explaining the operation of the measuring instrument described above. In the figure, Tl is the inertial input torque, Tf is the torque due to the current negatively fed back to the coil, ε is the difference between Tl and Tf, Gd is the transfer function of the detection section d, Ga is the gain of the amplification section a, and Eo is the output The voltage Gf indicates the gain of the feedback circuit f.

The following relationship holds between these.

From equation (1), if the gain of the amplifier section a is large (Ga) 1, then the following equation is obtained. That is, the output voltage Eo is approximately proportional to the penetrating input torque TI.

Here, if the moment of inertia of the moving part is I and the spatial rotation angular velocity of the moving body is TI = I... (4)
Or is it true? As shown in this equation, TI does not include the linear acceleration of the moving body or the influence of gravity at all. T.I.
What affects this is the rotational angular velocity of the moving body itself. Therefore, the frequency band of T1 is usually monotonic. As for the frequency characteristic between the inertial input torque TI and the output voltage EO, it is desirable that the gain is constant while the frequency band of TI changes from zero to a conceivable upper limit frequency. Therefore, to meet this requirement, the circuit configuration of the feedback loop is of a proportional type.

FIG. 3 is a circuit diagram showing an example of such a feedback loop. In the figure, the feedback circuit f connects the voltage EO to the resistor Rp2.
It is configured to perform a proportional operation in which the voltage is divided into the ratio of the voltage and the resistor Rp and a feedback current is given to the coil.

The transfer function in this case is Rp1/Rp2 when Ga)1
becomes. With this circuit configuration, we obtain. Equations (5) and (4) allow EO to be expressed as an inertial force in an angular system. i.e. here
The R-vertical is the constant force of this measuring instrument, ρ1.If the angular acceleration expressed in scale is MU, then Eo = Δ
......(6) is obtained. That is,
EO always provides an output proportional to the angular acceleration of the moving body.

Therefore, as shown in FIG. 4, by integrating Eo (1"l) by the first fire type division circuit ln1, the output -0 corresponding to the turning angular velocity Ω is obtained, and this is
The turning angle output θ can be obtained by integrating by the second fire type dividing circuit 1nz. FIG. 5 shows a specific example of the above-mentioned double integration circuit.

FIG. 6 is a waveform diagram for explaining the operation of the two-time integration circuit of FIG. The same figure (a) shows the angular acceleration, the same figure (b)
is the angular velocity Ω, and (c) is a waveform diagram of the rotation angle θ. When time 1 = 1G, assuming Ω = 0.0 = 0, time t
= to %tl (=Δt), the angular acceleration is kept constant (
If a), then Δ, Ω, and θ follow the course of A-+B in the first half on the left side of FIG.

Next, if the angular acceleration is kept constant (-a) between 1 = 1+ and t2 (=Δt), then t1 to t1 = -8 = aΔt - aΔt=Q In other words, the angular velocity is decelerated from aΔt of Ω1. t=t!
becomes O. Also, θ1-θ, ===' (Δt)2, so θt
=-(Δs2+-!-(Δt)2=a(Δt)2!22 is obtained. Therefore, M, Ω, and θ are shown in the second half B on the right side of Fig. 6.
Following the course of C, 1=1. The rotation angle θ is a(Δ
t).

A small ammeter-type inertia force torque measuring device having a pair of large inertia wheels at one end of the pointer, as shown in Fig. It can be built-in and made compact as a whole. In addition, the attached electronic calculation unit, which mainly consists of the first fire type branch circuit and the second fire type branch circuit, is integrated into a small size, so all of these devices can be attached to the human body or a robot manipulator. It is.

〔Effect of the invention〕

As explained above, according to the present invention, it can be attached to the extremities of a working human being or a robot manipulator in motion, and can be used to measure the spatial rotation angle, which has not been available until now, for applications such as human body motion analysis or manipulator control. It can be used as a container.

[Brief explanation of the drawing]

Figure 1 (a) shows an example of a measuring instrument used in the present invention -f'i
Fig. 1 (b) is a perspective view showing the installation and posture relationship, Fig. 2 is a block diagram for explaining the operation of the measuring instrument in Fig. 1 (0), and Fig. 3 is a circuit showing an example of a feedback loop. Figure 4 is a block diagram showing the principle of calculating the rotation angle using a double integration circuit, Figure 5 is a circuit diagram showing a specific example of the double integration circuit shown in Figure 4, and Figure 6 is an explanation of its operation. FIG. ξOη... Rotating surface of the moving body, 0ζ... Direction perpendicular to the rotating surface, (1)... Moving coil, O2... Rotating plow of the moving coil, (2)... Pointer , (13a), (13
b) −= 1 pair of large inertia wheels, Ti...input torque,
d...detection section, a...amplification section, (8)...output end, f...feedback circuit, Tf...torque due to negative feedback current, in and ln 2...first Next and second fire type circuit, θ... Spatial rotation angle. 1'(1

Claims (1)

[Claims] In a measuring instrument having a DC ammeter-type moving part installed with the axis of the moving coil aligned in a direction perpendicular to the rotation plane of a moving body rotating in space, one end of the pointer connected to the moving coil. A pair of inertia missing wheels whose weights are balanced are attached to the part, the moment of inertia of the movable part is increased, and the inertia torque during the rotation of the moving body is applied as an input torque to the movable part including the movable coil, and the pointer Displacement from the zero position at the other end is detected, converted into an electrical signal, amplified, and taken out to the output end, as well as negative feedback to the movable coil via a feedback circuit that operates proportionally, thereby generating the input torque and the negative feedback. By integrating twice the output of a dynamic torque measuring device configured to apply a differential torque from the torque caused by the current to the moving coil, the spatial rotation angle when the moving body rotates is automatically calculated. A spatial rotation angle calculation device characterized by the following.