JP3984361B2 - Twist angle measuring device for human joint - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for measuring a twist angle of a human body joint that can contribute to occupational safety and work comfort by accurately measuring and evaluating the bending and twist angles of a human body joint.
[0002]
[Prior art]
In the occupational health field, if you take a heavy posture during work, such as handling heavy objects, you will bend and twist the joints of each part of the body (human body), resulting in health such as tendonitis and low back pain. It is said to cause a failure.
[0003]
In each part of the body (human body), although depending on the operation frequency, the burden load, and the bending angle, it is said that the probability of occurrence of a failure is higher when the twist is involved than the bending alone. Therefore, it is important from the viewpoint of occupational safety and work comfort to accurately measure and evaluate joint bending and twisting. However, the current situation is that the relationship between the degree of twist and health problems is not well understood. The apparatus of the present invention is for appropriately grasping the above.
[0004]
As for the bending operation of the joint of a human body, conventionally, an apparatus that simply measures the operation and angle by a sensor using a rotation angle sensor, a strain gauge, or the like has been put into practical use. However, only twisting devices were used for twisting motion.
[0005]
[Problems to be solved by the invention]
In the device using the strain gauge,
(1). Durability is inferior.
(2). The device is expensive.
(3). Requires complex electronic circuitry.
(4). It is impossible to measure the twisting movements that a large skeleton such as the spine and many skeletons cooperate.
There were various problems such as, and it was not widely used and used.
[0006]
In order to solve the above-mentioned problems, the present invention is relatively simple, small and lightweight, durable, inexpensive, and can measure the twisting motion of a large joint such as the spine. An object of the present invention is to provide a device for measuring the twist angle of a human joint.
[0007]
[Means for Solving the Problems]
In order to achieve this object, the present invention has the following configuration.
[0008]
A. The first fastening means provided on the outer periphery of body surface comprising one of skeletal across the body of the joint is provided with second fastening means to the outer circumference of the body surface including the other skeleton across the joint, the first the rotation angle sensor with the rotation shaft attached along the long axis direction of the skeleton 1 of the fixing means, the sensor actuating member extending along the longitudinal direction of the backbone from the rotational axis of the rotational angle sensor the first attached to the second fastening means, based on the relative rotation angle of the tangential direction between the rotating the first securing means which is measured by the angle sensor and the second fixing means, the skeleton as a rotation center It is characterized by measuring the twist angle and its temporal change.
[0009]
B. A coil spring is interposed in the middle of the sensor operating body .
[0010]
C. The upper xenon capacitors operating body as a flexible shaft, is characterized in that connected the rotation angle sensor in the display device, the recording device.
[0011]
[Action]
In the apparatus for measuring a twist angle of a human body joint according to the present invention, the following operation is performed.
[0012]
(1) According to the twist angle measuring apparatus of the human body joints according to the first aspect of the invention, the first fastening means provided on the outer periphery of body surface comprising one of skeletal across the body of the joint, across the joint it is also the outer circumference of the body surface including the other skeleton providing the second fixing means, the rotating shaft rotational angle sensor to the first fastening means is attached along the long axis direction of the skeleton, the rotation angle A sensor operating body extending along the long axis direction of the skeleton from the rotation shaft of the sensor is attached to the second fixing means . Thus , the tangent line between the first fixing means and the second fixing means can be obtained by the rotation angle sensor without being affected by the movements of flexion, extension, abduction, adduction and drawing circle of the joint. The relative rotation angle of the direction can be measured, and based on this relative rotation angle, the twist angle of the skeleton serving as the rotation center and its temporal change can be measured accurately, simply and quickly .
[0013]
( 2 ) According to the apparatus for measuring a twist angle of a human body joint according to the invention described in claim 2, since the coil spring is interposed in the middle of the sensor operating body, the sensor operating body can be moved by the coil spring even when the joint is bent. Since it has a margin, it is not caught or the operation is not significantly restricted. In this case, even if the coil spring expands and contracts, the deformation around the rotation axis is in a very small range.
[0014]
(3) According to the twist angle measuring apparatus of the human body joint according to a third aspect of the invention, the above xenon capacitors operating body as a flexible shaft, the indicator on the rotation angle sensor, by connecting the recording apparatus, durability The measurement data can be immediately confirmed and recorded.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of bending and twisting motions of each joint of the entire body, where dotted arrows indicate extension and bending motions, and solid arrows indicate abduction and adduction (twisting) motions. FIG. 2 is a schematic diagram of the principle of measuring the twisting motion. Regarding the abduction and adduction (twisting) movements indicated by the solid arrows in FIG. 1, (1): twisting when the trunk is upright, or other joints In case of twisting, {circle over (2)} indicates the state of the free end side, fixed end side, and top surface of the free end when the trunk is bent, α is the twist angle, ○ is the fixed position of the angle sensor and flexible shaft It is.
[0016]
The measurement principle is that when the twisting operation is performed, the rotation angle of the center of rotation and the angle changed in the tangential direction of a certain point on the outer periphery are the same as long as the cross-sectional shape of the body does not change. Therefore, if the relative angle in the tangential direction between two points on the body surface is measured, the twist angle of the joint serving as the center of rotation can be grasped. At this time, even if a bending operation or the like is included between the two points, the flexible shaft is not deformed and interfered only in the axial direction, and only the twist angle can be measured. Measurement of the rotation angle (twisting angle) around the axis with the major axis of the skeleton as the rotation axis is not affected by the movements of joint flexion, extension, abduction, adduction, and drawing circles. To.
[0017]
FIG. 3 shows an embodiment of a human body joint twist angle measuring apparatus according to the present invention. This device is based on the measurement principle shown in FIG. 2, and is fixed to the outer periphery of the body surface including one skeleton with the joint of the human body shown in FIG. 1 (band, double-sided tape, adhesive tape, clip, etc.): first Fixing means 1 and fixing jig (band, double-sided tape, adhesive tape, clip, etc.) on the outer periphery of the body surface including the other skeleton sandwiching the joint: the second fixing means 2 is provided and the first fixing A rotation angle sensor 3 is attached to the means 1, and a flexible shaft 4 which is a sensor operating body extending from the sensor 3 is attached to the second fixing means 2, and the flexible shaft 4 is used as a rotation axis in the longitudinal direction of the skeleton. A relative rotation angle between a plurality of surrounding skeletons is measured, and a twist angle α of the skeleton and its temporal change are measured. A display device or a recording device 5 is connected to the rotation angle sensor 3.
[0018]
Another embodiment of the measuring device according to the invention is shown in FIG. This embodiment is the same as the embodiment shown in FIG. 3 except that the coil spring 6 is interposed in the middle of the flexible shaft 4 in the embodiment shown in FIG. In this embodiment, when the joint is bent, the flexible shaft 4 is caught if there is no allowance, or the operation is remarkably restricted. Therefore, the allowance is provided by the coil spring 6. In this case, even if the coil spring 6 expands and contracts, the deformation around the rotation axis is in a very small range.
[0019]
The twist angle measuring device for a human body joint according to the present invention is attached to the body and measured, for example, as shown in FIGS. FIG. 5 shows the measurement device mounted on the elbow joint. The first fixing jig (band) 1 is fixed to the upper arm, the second fixing jig (band) 2 is fixed to the forearm, and the twist angle of the forearm is determined. taking measurement. FIG. 6 shows the measurement device mounted on the trunk, with the first fixing jig (band) 1 fixed to the waist and the second fixing jig (band) 2 fixed to the chest, and the twist angle of the chest is adjusted. taking measurement. FIG. 7 shows a measurement apparatus in which a sensor 3 is attached to the side of a first fixed jig (band) 1 and is mounted on the trunk to the lower limbs. The first fixed jig (band) 1 is attached to the chest. The second fixing jig (band) 2 is fixed to the lower limb, and the twist angle of the lower limb is measured.
[0020]
FIG. 8 shows a case where a measuring device when the sensor 3 cannot be attached to the side surface of the first fixed jig (band) 1 is attached to the trunk, and the first fixed jig (band) 1 is crossed from the chest. It fixes over a shoulder part, the sensor 3 is attached to the intersection, the 2nd fixing jig (band) 2 is fixed to a waist part, and the twist angle of a waist part is measured. FIG. 9 shows a measurement device mounted on two or more joints of the elbow-shoulder joint. The first fixing jig (band) 1 is fixed to the shoulder side portion of the upper arm base, and the second fixing jig is attached to the lower part of the upper arm. (Band) 2a and second fixing jig (band) 2b are fixed to the wrist, and the twist angles of the forearm and upper arm are measured.
[0021]
Next, a test method and a test result in which a test for confirming the possibility of measurement of the twisting operation of the body and the handling property by the twist angle measuring device for the human body joint will be described.
[0022]
[Test method]
1) Verification with video motion analysis system First, subjects (2 males and 1 female) are in a chair sitting position (trunk upright) and standing forward bent (trunk tilt 90 degrees) in 30 or 40 cycles. Twist the upper body at a speed of 1 min / min, and determine the relative twist angle of the L4 lumbar position (about the height of the belt of the trousers) and the Th6 thoracic vertebra position (about the height of the mid-scapular height) with the twist sensor 3 Measured and compared using an expression motion analysis system (Electric Measurement Sales Co., Ltd., Quick-MAG SYSTEM 1).
[0023]
2) Presence or absence of interference with flexion movements In the chair sitting (trunk upright) state, (1) trunk forward bending / standing movement only, (2) L4 lumbar vertebra when twisting movement is added to forward bending / standing movement The relative twist angle of the Th6 thoracic vertebra was measured with the twist sensor 3, and the influence of bending and stretching movements was investigated.
[0024]
[Test results]
1) FIG. 10 shows a part of the collation measurement result with the video motion analysis system. From this figure, it is clear that the measured values by both methods are almost the same.
2) FIG. 11 shows a part of the measurement result of the presence / absence of interference with the bending operation. From this figure, it is clear that the bending and stretching operations have little effect on the measured values.
[0025]
【The invention's effect】
As described above, according to the human body joint twist angle measuring apparatus of the present invention, the following effects can be obtained.
[0026]
(1) According to the invention the twist angle measuring apparatus of the human body joint according to according to claim 1, the first fastening means provided on the outer periphery of body surface comprising one of skeletal across the body of the joint, the joint The second fixing means is also provided on the outer periphery of the body surface including the other skeleton sandwiched, and the rotation angle sensor is attached to the first fixing means so that the rotation axis is along the longitudinal direction of the skeleton , and the rotation is performed. the sensor operating body from the axis of rotation of the angle sensor extending along the longitudinal direction of the skeleton attached to the second fastening means, the rotation of the first fixing means which is measured by the angle sensor and the second fixed Based on the relative rotation angle in the tangential direction with the means, the twist angle of the skeleton, which is the center of rotation, and its temporal change were measured, so joint flexion, extension, abduction, adduction Without being affected by each movement of the drawing circle, The relative rotation angle between multiple skeletons around the axis of the skeleton's long axis can be measured accurately, simply, quickly, and easily. By grasping changes, it is possible to contribute to occupational safety and work comfort.
[0027]
( 2 ) According to the apparatus for measuring a twist angle of a human body joint according to the invention described in claim 2, since the coil spring is interposed in the middle of the sensor operating body, the sensor operating body is a coil spring even when the joint is bent. Therefore, there is a margin, and it is not caught or the operation is not significantly restricted. In this case, even if the coil spring expands and contracts, the deformation around the rotation axis is in a very small range.
[0028]
(3) According to the twist angle measuring apparatus of the human body joints according to the invention of claim 3, wherein, as the flexible shaft of the sensor actuating member, the rotation angle sensor in the display device, since the connecting recording apparatus, the device itself It is durable, and measurement data can be checked and recorded immediately.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of bending and twisting operations of each joint of the entire body.
FIG. 2 is a schematic diagram of the principle of measuring twisting motion.
FIG. 3 is a schematic diagram of a device for measuring a twist angle of a human body joint according to the present invention.
FIG. 4 is a schematic diagram of another embodiment of the measurement apparatus.
FIG. 5 is an example of attaching the measuring device to the elbow joint.
FIG. 6 is an example of attaching the measuring device to the trunk.
FIG. 7 is an example in which a measuring device with a sensor attached to a side surface is attached to the trunk to the lower limbs.
FIG. 8 is an example in which a measuring device is mounted on the trunk when a sensor cannot be attached to the side surface.
FIG. 9 is an example in which the measuring device is attached to two or more joints of the elbow-shoulder joint.
FIG. 10 is a graph showing a sitting position and a twist of 40 cycles / minute.
FIG. 11 is a graph showing measurement results in a sitting position.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fixing jig (band): 1st fixing means 2, 2a, 2b Fixing jig (band): 2nd fixing means 3 Rotation angle sensor 4 Flexible shaft 5 Display, recording device 6 Coil spring α Twist angle ○ Twist angle sensor And fixing position of flexible shaft

Claims (3)

A first fixing means is provided on the outer periphery of the body surface including one skeleton across the joint of the human body,
A second fixing means is also provided on the outer periphery of the body surface including the other skeleton sandwiching the joint,
A rotation angle sensor is attached to the first fixing means so that the rotation axis is along the long axis direction of the skeleton ,
A sensor actuating body extending along the long axis direction of the skeleton from the rotation axis of the rotation angle sensor is attached to the second fixing means,
Based on the relative rotation angle in the tangential direction between the first fixing means and the second fixing means measured by the rotation angle sensor, the twist angle of the skeleton serving as the rotation center and its temporal A device for measuring a twist angle of a human joint characterized by measuring changes. 2. The apparatus for measuring a twist angle of a human joint according to claim 1 , wherein a coil spring is interposed between the sensor operating bodies . The upper xenon capacitors operating body as a flexible shaft, the rotation angle sensor in the display device, the twist angle measuring apparatus of the human body joint of claim 1 or 2, wherein the connected recording device.

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