TWI382834B - Digital goniometer - Google Patents

Description

Digital protractor

The present invention relates to a device for measuring joint mobility. It is especially suitable for joint activity testing of rehabilitation patients.

The tool commonly used for physical therapy to evaluate the joint mobility of the extremities is the universal goniometer. The evaluator must follow the standard test procedures (such as the specific placement of the patient and the joint, the axis of the joint scale, and the arms at both ends must be aligned with the specified part). And, as the activity progresses to the final angle, the evaluator must give overpressure to assess the end feels of the tissue.

However, in the clinical implementation of this assessment, often encountered patients with weakness, poor control of movement, excessive muscle tone, or patients with weight or body size far greater than the evaluator. It is often impossible to perform this assessment independently. If it is barely implemented, it may cause too much error. At the same time, the judgment of the nervous end of the hand is easy to make a mistake, which leads to the correctness of the data, and successively affects subsequent clinical decisions.

Therefore, if there is a digital protractor that automatically displays data (appears like a watch), it is fixed to the distal end of the test joint limb, and the performer only needs to help support the patient's limb and determine that the patient is doing the correct action. In addition, it is easier to give the weight to evaluate the terminal feel at the end of the action; start and stop The angle can be read directly on the digital protractor. In this way, the evaluator does not have to pay attention to the correct position of the fixed-angle square while being busy supporting the patient's limb, and there is no trouble that the hand cannot be given heavy pressure.

Therefore, the digital angle display makes the clinical evaluation of limb joint mobility easier and more accurate. The correctness of the data obtained is guaranteed to help the use of medical decisions

An apparatus for measuring joint mobility, comprising: (a) a housing; (b) an instruction input device on a surface of the housing; (c) a control device that accepts an instruction of the input device; (d) An acceleration measuring device, wherein the acceleration analog signal is output to the control device and accepts a measurement start command of the control device; and (e) a fastening device that connects the outer casing to the limb of the subject. The acceleration measuring device is an inertial sensor for detecting joint activity. The command input device is a measurement start, stop and result button.

The invention further comprises a display device or a voltage stabilizing circuit device, wherein the display device can be an LED with a function of voice reading, and the device of the voltage stabilizing circuit is used for voltage regulation of 3.3 volts. The fastening device is secured to the limb with a magic felt.

Function description of each device: The design of the present invention is as shown in FIG. 1 , and is driven by a command input device 20 , a control device 30 , an acceleration measuring device 40 , a display device 50 , a voltage stabilizing circuit device 60 , and a fastening device . The device 70 is composed, and the realization diagram is as shown in Fig. 2. Each device is responsible for the following work: Display device: The device is composed of a four-segment and seven-segment display, and its function is to display the joint angle and provide the user with an evaluation record. The device can also be changed to the speaker 80 to perform the measurement result reading by voice.

Command input device: The device is composed of three buttons or other components in the form of switches, and is mainly responsible for receiving user control commands. The three buttons of the device are Offset key 90, Start key 100, Stop key 110; Offset key is the measurement zero reset setting, Start key measurement start setting, and Stop key is the measurement stop setting. The input device of this instruction can also be controlled by voice control by using a microphone.

Acceleration measuring device: The device is composed of three mutually orthogonal accelerometers, which mainly use the three sensors to detect the gravitational acceleration of gravity, as a reference for the angle of the object to be tested in space. According to the measurement principle, as shown in Fig. 3, the angle between the acceleration gauge and the gravity is θ, and tan θ=a/b, then θ=tan ^-1 (a/b) can be obtained.

Control device: The device is composed of a microcomputer controller, and its function is divided into three parts, 1) receiving the control command of the control input device, and 2) performing the three-axis acceleration variation provided by the joint angle measuring device. The calculation of the movement angle of the joint to be tested, and 3) controlling the display output of the numerical display device to provide the user with a range of angles of the joint movement. 4 is a flow chart showing the operation of the control device of the present invention.

Regulator circuit device: used for 3.3 volt voltage regulation.

Fastening device: The invention is applied to the limb with a magic felt.

Steps

The proximal limb 120 (such as the arm), the joint 130, and the limb 140 to be tested (such as the forearm) remain stationary at the measurement starting point, as shown in Figure 5:

1. Turn on the power of the present invention.

Second, the invention is first attached to the limb to be tested.

3. Place the limb to be tested at the measurement starting position.

4. Press the Offset key to set the current joint angle position to zero.

5. Press the Start button to start the measurement. The numerical display device of the present invention also exhibits a corresponding angular change as the angle of the joint to be tested changes.

6. When the limb to be tested is placed at the maximum joint movement angle, pressing the Stop button, the present invention stops the measurement and displays the last measured angle value on the display device to provide the user with the record.

7. To measure the joint activity of the same limb but in different directions, repeat steps 3-8 to move the limb toward the other direction.

8. To measure the joint activities of different limbs, first remove the invention from the previous limbs and repeat the two to six steps.

10‧‧‧Design of the invention

20‧‧‧Key input device

30‧‧‧Control device

40‧‧‧Acceleration measuring device

50‧‧‧ display device

60‧‧‧Variable circuit device

70‧‧‧ fastening device

80‧‧‧Speakers

90‧‧‧Offset key

100‧‧‧Start button

110‧‧‧Stop button

120‧‧‧ proximal limb

130‧‧‧ limbs to be tested

140‧‧‧ joint

Figure 1 is a plan view of the present invention.

Figure 2 The entity of the invention.

Figure 3 shows the principle of the invention, (a) is before projection; (b) is a projection.

Figure 4 is a flow chart showing the operation of the present invention.

Figure 5 Use of the invention, (a) is the test starting point; (b) is the test end point.

10‧‧‧Design of the invention

20‧‧‧Key input device

30‧‧‧Control device

40‧‧‧Acceleration measuring device

50‧‧‧ display device

60‧‧‧Variable circuit device

70‧‧‧ fastening device

Claims (10)

A device for measuring an angle of joint movement, comprising: (a) a housing; (b) a fastening device coupled to the housing to secure the integral device to one of the subject's limbs; (c) an instruction input a device on the surface of the outer casing for receiving instructions for starting, stopping, and returning to zero; (d) a control device that accepts commands from the command input device; and (e) an acceleration measuring device Receiving a start command generated by the control device, and generating a three-axis acceleration analog signal for output to the control device; wherein the control device calculates an angle between the acceleration measuring device and the gravitational acceleration according to the three-axis acceleration signal The angle is the first angle between the limb and the gravity in the first position; when the limb moves to the second position, the control device calculates the second angle of the limb with the gravity in the second position And further calculating the movement angle of the joint where the limb is located by the first angle and the second angle. The device according to item 1 of the application scope further comprises a display device. According to the device of the second aspect of the application, the display device is an LED. According to the device of the first aspect of the application, the device further comprises a voltage stabilizing circuit. The device of claim 1, wherein the fastening device is secured to the limb by a magic felt. The device of claim 2, wherein the display device is attachable to a voice reading function. The device of claim 1, wherein the acceleration measuring device is an inertial sensor. The device of claim 1, wherein the command input device is a button group including a start button, a stop button, and a zero button. The device according to item 4 of the application scope, wherein the device of the voltage stabilizing circuit is used for voltage regulation of 3.3 volts. The device of claim 1, wherein the command input device is a microphone, and the command input of starting, stopping, and returning to zero is performed in a voice-activated manner.