Wearable device and method of operating the same

Abstract

A wearable device can include a motor, a motor driver circuit, a frame connected to the motor, a processor, and a sensor, wherein the frame is worn on a user's body to support the body, the processor is configured to generate a control signal for controlling electrical connections in the motor driver circuit, and the sensor is configured to sense a body motion of the user. The processor is further configured to provide an exercise load through the frame according to a speed of the sensed body motion by controlling a rate of each change between a first control state and a second control state based on the speed of the body motion, wherein the electrical connections in the motor driver circuit are closed-loop in the first control state and open-loop in the second control state.

Description

TECHNICAL FIELD

[0001] At least one example embodiment relates to a wearable device worn on a user's body to provide an exercise function and / or an operating method of the wearable device. BACKGROUND

[0002] In general, a walking assistance device refers to a mechanism or device that helps a patient who cannot walk autonomously due to various diseases, accidents, etc. to perform a walking exercise for rehabilitation treatment. As the aging society has recently intensified, more and more people experience inconvenience in walking or have difficulty in normal walking due to joint dysfunction problems, and interest in a walking assistance device is increasing. The walking assistance device is worn on a user's body to assist the user in walking by providing a desired (or optionally, necessary) muscle power, and to induce the user to walk in a normal walking pattern. SUMMARY

[0003] Some example embodiments relate to a wearable device for providing an exercise load to a user when worn on the user's body.

[0004] In some example embodiments, the wearable device includes a frame configured to be worn on a user's body to support the body, a motor configured to be attached to the frame, a motor driver circuit connected to the motor, a sensor configured to sense a body motion of the user, and a processor configured to generate a control signal for controlling an electrical connection in the motor driver circuit to provide the exercise load through the frame according to a speed of the body motion by controlling a ratio of each change between a first control state and a second control state based on the control signal, wherein the first control state is a state in which the electrical connection in the motor driver circuit is closed, and the second control state is a state in which the electrical connection in the motor driver circuit is open.

[0005] In some example embodiments, the processor is further configured to periodically and alternately repeat switching between the first control state and the second control state based on the ratio of each change.

[0006] In some example embodiments, the processor is further configured to determine the speed of the body motion based on the body motion, and adjust the ratio of each change between a duration of the first control state and a duration of the second control state based on the determined speed.

[0007] In some example embodiments, the processor is further configured to adjust the ratio of each change to correspond to a second speed if the speed of the body motion changes from a first speed to the second speed.

[0008] In some example embodiments, the processor is further configured to adjust the rate of change per time if the second speed is greater than the first speed by decreasing a duration of the first control state and increasing a duration of the second control state.

[0009] In some example embodiments, the processor is further configured to adjust the rate of change per time if the second speed is less than the first speed by increasing a duration of the first control state and decreasing a duration of the second control state.

[0010] In some example embodiments, the processor is further configured to adjust the rate of change per time based on the target exercise load and a speed of the body motion.

[0011] In some example embodiments, the processor is configured to receive an input of the target exercise load from a user.

[0012] In some example embodiments, the processor is further configured to generate the exercise load by forming a closed loop in the first control state without driving the motor using power of a battery.

[0013] In some example embodiments, the processor is further configured to control the motor to generate a torque in a direction that hinders the body motion by supplying power of a battery to the motor, and to generate the exercise load by controlling a change between the first control state and the second control state.

[0014] In some example embodiments, the motor driver circuit includes a plurality of switches configured to control electrical connections in the motor driver circuit based on the control signal output from the processor.

[0015] In some example embodiments, the wearable device is configured to be worn on a lower body of a user to provide resistance to the lower body of the user.

[0016] Other example embodiments relate to a method of operating a wearable device for providing an exercise load to a user when worn on a body of the user.

[0017] In some example embodiments, the method can include sensing a body motion of the user via a sensor, and generating a control signal for controlling electrical connections in a motor driver circuit of the wearable device based on a speed of the body motion to provide the exercise load through the frame according to the speed of the body motion by controlling a rate of change per time between a first control state and a second control state based on the control signal, wherein the first control state is a state in which the electrical connections in the motor driver circuit are closed, and the second control state is a state in which the electrical connections in the motor driver circuit are open.

[0018] In some example embodiments, the step of generating the control signal comprises generating a control signal for periodically and alternately repeating switching between the first control state and the second control state.

[0019] In some example embodiments, the step of generating the control signal comprises determining a velocity of the body motion based on the body motion, and generating a control signal for adjusting the change ratio between the duration of the first control state and the duration of the second control state based on the velocity of the body motion.

[0020] In some example embodiments, the step of generating the control signal comprises generating a control signal referencing adjusting the change ratio to a second velocity in response to the velocity of the body motion changing from a first velocity to the second velocity.

[0021] In some example embodiments, the step of generating the control signal comprises generating a control signal for adjusting the change ratio by decreasing the duration of the first control state and increasing the duration of the second control state in response to the second velocity being greater than the first velocity.

[0022] In some example embodiments, the step of generating the control signal comprises generating a control signal for adjusting the change ratio by increasing the duration of the first control state and decreasing the duration of the second control state in response to the second velocity being less than the first velocity.

[0023] Some example embodiments relate to a non-transitory computer readable storage medium storing instructions that, when executed by a processor, cause the processor to perform an operational method of a wearable device for providing an exercise load to a user when worn on the user's body.

[0024] Additional aspects of example embodiments will be set forth in part in the description that follows, and in part will be apparent from the description, or can be learned by practice of the disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0025] These and / or other aspects will become apparent and more readily appreciated from the following description of example embodiments, taken in conjunction with the accompanying drawings in which:

[0026] Figure 1 A wearable device worn on a user's body according to an example embodiment is shown;

[0027] Figure 2 An external structure of a wearable device according to an example embodiment is shown;

[0028] Figure 3A configuration of a wearable device according to an example embodiment is illustrated;

[0029] Figure 4 Operation of a motor driver circuit according to an example embodiment is illustrated;

[0030] Figure 5 Control operation of a processor according to an example embodiment is illustrated;

[0031] Figure 6A , Figure 6B and Figure 6C Control operation of a processor according to an example embodiment is illustrated;

[0032] Figure 7 and Figure 8 Control operation of a wearable device according to an example embodiment is illustrated;

[0033] Figure 9 is a flowchart illustrating an operation method of a wearable device according to an example embodiment. DETAILED DESCRIPTION

[0034] The following detailed description includes specific details for the purpose of providing a thorough understanding of the technical concepts. However, it will be apparent to those skilled in the art that the example embodiments can be practiced without these specific details. In some instances, well-known structures and functions have not been described in detail in order to avoid obscuring the understanding of the example embodiments.

[0035] Terms such as first, second, etc. can be used in this document to describe components. Each of these terms is not intended to define a nature, order or sequence of the corresponding component, but is only used to distinguish the corresponding component from other components. It should be noted that if it is described that one component is "connected", "coupled" or "joined" to another component, although the first component can be directly connected, coupled or joined to the second component, a third component can be "connected", "coupled" and "joined" between the first component and the second component.

[0036] The singular form is intended to include the plural form unless the context clearly indicates otherwise. It will be further understood that the terms "comprise" and / or "include" as used herein specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0037] Unless otherwise defined herein, all terms (including technical or scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in a generally used dictionary should be interpreted as having a meaning that is consistent with its meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0038] Hereinafter, example embodiments will be described in detail with reference to the accompanying drawings. When example embodiments are described with reference to the accompanying drawings, like reference numerals refer to like components, and repetitive description thereof will be omitted.

[0039] Figure 1 A wearable device according to an example embodiment is shown worn on a user.

[0040] Referring to Figure 1 The wearable device 110 is a device worn on the body of the user 100 to assist the user 100 in exercising. The wearable device 110 can be worn on the lower body (legs, ankles, knees, etc.), the upper body (torso, arms, wrists, etc.), or the waist of the user 100 to provide resistance to the body movement of the user 100, thereby enhancing the exercise effect of the user 100. The resistance is provided to impede the movement of the user 100 or to provide the resistance against the movement of the user 100, and the resistance can be a force acting in a direction opposite to the direction of the movement of the user 100 when the user 100 moves. Hereinafter, the resistance can also be referred to as "exercise load". The wearable device 110 can further enhance the exercise effect of the user 100 by providing the exercise load to the body of the user 100 when worn on the legs. The user 100 can perform a walking movement while wearing the wearable device 110 to exercise. In this case, the wearable device 110 can apply the exercise load to the legs of the user 100 during the walking movement of the user 100. Hereinafter, the wearable device 110 worn on the lower body (legs) will be described as an example. However, as described above, the wearable device 110 can be worn on a body part other than the lower body, and its shape and configuration can vary according to the body part on which the wearable device 110 is worn. In the following description, "legs" can be replaced with another body part.

[0041] In addition to assisting the user 100 in exercising as described above, the wearable device 110 can be used to assist the user 100 in walking. For example, the wearable device 110 can help the user 100 to walk by assisting one or each leg of the user 100. The wearable device 110 can enable the user 100 to walk independently or for a long time by providing a force required for the user 100 to walk, thereby extending the walking ability of the user 100. The force provided to assist the user to walk can be in a direction opposite to the resistance provided to impede the movement of the user 100. Alternatively, the wearable device 110 can improve the abnormal walking habit or walking posture of the user.

[0042] Figure 2 An external structure of a wearable device according to an example embodiment is illustrated.

[0043] Referring to Figure 2 The wearable device 110 includes a frame configured to secure the wearable device 110 to the body of the user 100 and to support the body when the wearable device 110 is worn on the body of the user 100. The frame can include, for example, a waist-worn frame configured to secure the wearable device 110 to the waist of the user 100 and a leg-worn frame worn on the leg of the user 100 to secure a portion of the wearable device 110 to the leg of the user 100. Depending on the implementation form of the wearable device 110, the shape or configuration of the frame can be modified to suit the implementation form.

[0044] In an example embodiment, a main circuit (or alternatively, a controller) 230 can be placed behind the lower back of the user 100, in which a processor, a memory, etc. are provided in the main circuit 230 for controlling the operation of the wearable device 110. In the vicinity of each of the left hip joint 220L and the right hip joint 220R of the user 100, a motor controlled by the processor and a sensor configured to sense the body movement of the user 100 can be provided.

[0045] When power is supplied to the motor near each of the left hip joint 220L and the right hip joint 220R, the motor operates. In this case, the force output from the motor is transmitted to each leg-wearable frame through each of the left transmission part 240L and the right transmission part 240R, and the force transmitted to the leg-wearable frame is applied to the leg of the user 100. If the user moves the left leg, the leg-wearable frame worn on the left leg moves together, and the movement of the leg-wearable frame can be sensed by the sensor provided near the left hip joint 220L through the left transmission part 240L. For example, an encoder can be provided near the left hip joint 220L to measure the rotational position or rotational speed of the movement of the left transmission part 240L corresponding to the movement of the left leg. If the user moves the right leg, the leg-wearable frame worn on the right leg moves together, and the movement of the leg-wearable frame can be sensed by the sensor (such as an encoder) provided near the right hip joint 220R through the right transmission part 240R. The encoder can measure the rotational position or rotational speed of the movement of the right transmission part 240R corresponding to the movement of the right leg.

[0046] When the wearable device 110 operates in the exercise mode, the wearable device 110 can generate a target exercise load by controlling the electrical connection in the motor driver circuit without driving the motor included in the wearable device 110 by supplying power to the motor. In this case, the exercise load acting in the opposite direction of the body movement of the user 100 is generated by the motor of the wearable device 110, and is transmitted to the body of the user 100 through the leg-wearable frame through each of the left transmission part 240L and the right transmission part 240R. Meanwhile, the wearable device 110 can control the electrical connection in the motor driver circuit to adapt to the body movement speed of the user 100, thereby stably generating the target exercise load even if the body movement speed of the user 100 changes. Hereinafter, the configuration and operation of the wearable device 110 will be further described with reference to the accompanying drawings.

[0047] Figure 3 A configuration of a wearable device according to an example embodiment is illustrated.

[0048] Referring to Figure 3The wearable device 300 can be a block diagram of electronic elements included in the wearable device 300. The wearable device 300 can generate an exercise load by repeatedly controlling the switching connection in the motor driver circuit 320 without driving the motor 310 by supplying power to the motor 310. Through this control, an exercise load can be generated without providing power of a battery that supplies power to the wearable device 300 to the motor 310. Accordingly, power consumption of the battery can be relatively reduced, which can lead to an increase in the operating time of the wearable device 300. Further, since the motor 310 is not directly driven by receiving power, relatively less noise can be generated for an exercise load compared to the case of driving the motor 310. In addition, the wearable device 300 can provide an exercise load of a desired or predetermined size (or intensity) to a user by monitoring the user's motion and adaptively controlling the switching connection in the motor driver circuit 320 according to the user's motion. Hereinafter, the operation of the wearable device 300 will be described in more detail based on components of the wearable device 300.

[0049] The wearable device 300 includes a motor 310, a motor driver circuit 320, a sensor 330, a processor 340, and a memory 350. Further, as shown in Figure 4 The wearable device 300 can further include a battery 450, as shown.

[0050] In some example embodiments, the battery 450 can be a rechargeable battery such as a lithium ion battery, for example, a lithium iron phosphate (LiFePO4) battery, and the wearable device 300 can include a battery management system (BMS) that displays a remaining battery power to a user to intelligently control the wearable device 300 to save and / or generate power.

[0051] When the motor 310 is driven by receiving power, the motor 310 can provide a force to assist or impede a leg motion of a user. The motor 310 can include at least two motors, and when the user wears the wearable device 300, the motors can be located near each of the user's hip joints. In this case, the motor located near the right hip joint can provide a force to assist and / or impede a motion of the right leg, and the motor located near the left hip joint can provide a force to assist and / or impede a motion of the left leg.

[0052] In some example embodiments, the processor 340 can determine whether to drive power to provide a force to assist and / or impede a leg motion of a user based on a remaining battery power. For example, when the remaining battery power is lower than a threshold value, the processor 340 can attempt to save battery power and not provide an additional force to impede a leg motion of the user.

[0053] The wearable device 300 can operate in a walking assistance mode for assisting a user in walking, or in an exercise mode for impeding a leg movement of the user to increase an exercise effect of the user. In the walking assistance mode, the motor 310 can output an assistance force to assist the user in walking. In the exercise mode, as described above, the motor 310 can generate an exercise load by controlling a switch connection in the motor driver circuit 320 without supplying power to the motor 310. Alternatively, the motor 310 can generate an artificial force impeding the leg movement of the user based on the power supplied to the motor 310 and the control of the switch connection in the motor driver circuit 320. For example, when it is difficult to generate a target exercise load only by controlling the switch connection in the motor driver circuit 320, the motor 310 can be additionally driven to generate a force impeding the body movement of the user.

[0054] The motor driver circuit 320 is a circuit that controls the operation of the motor 310 under the control of the processor 340, and can control a path of a current supplied to the motor 310 or an electrical connection around the motor 310. The motor driver circuit 320 can drive the motor 310 or stop driving the motor 310 based on a control signal received from the processor 340. The motor driver circuit 320 can include a plurality of switches for controlling the electrical connection around the motor 310, and can control the switches of the motor driver circuit 320 based on a control signal received from the processor 340. The motor driver circuit 320 can include a separate internal processor configured to control the switches. In this case, the internal processor can receive a control signal from the processor 340 and control the switches based on the received control signal.

[0055] In an example embodiment, the motor driver circuit 320 can include a control circuit, such as an H-bridge circuit, for controlling the electrical connection around the motor 310. The H-bridge circuit is a circuit capable of switching the polarity of the voltage applied to a load, such as the motor 310. Figure 4 An example of the H-bridge circuit is shown in the middle.

[0056] Figure 4 An operation of the motor driver circuit according to an example embodiment is shown.

[0057] Referring to Figure 4The H-bridge circuit controls the electrical connections around the motor 310 through a plurality of switches 410, 420, 430, and 440. The switches 410, 420, 430, and 440 can be implemented as semiconductor devices, such as metal-oxide-semiconductor field-effect transistors (MOSFETs). When the first switch 410 and the fourth switch 440 are turned on (or shorted) and the second switch 420 and the third switch 430 are turned off (or opened) under the control of the processor 340, the motor 310 can be powered from the battery 450. Alternatively, when the second switch 420 and the third switch 430 are turned on and the first switch 410 and the fourth switch 440 are turned off under the control of the processor 340, the motor 310 can be powered from the battery 450. When both the third switch 430 and the fourth switch 440 are turned off, the motor 310 is not powered from the battery 450.

[0058] Referring again to FIG. 1, Figure 3 The sensor 330 can sense a leg movement as a body movement of the user, and transmit information about the sensed leg movement to the processor 340. The sensor 330 can include one or more sensors configured to sense a hip joint angle, a leg movement speed or acceleration, and a leg movement direction of the user, e.g., an encoder, an acceleration sensor, an inertial sensor, a gyro sensor, etc. When the sensor 330 includes an encoder, the encoder can detect a rotation speed and a rotation position of an encoder shaft according to a leg movement of the user. The rotation angle of the encoder shaft can correspond to the joint angle of the user. The encoder can transmit a bit value corresponding to the rotation position of the shaft to the processor 340, and the processor 340 can calculate the rotation angle of the shaft based on the received bit value. The processor 340 can calculate the rotation speed (angular velocity) or the change in the rotation angle of the shaft during a corresponding period of time based on the difference between the bit values received at different times. In this document, the "speed of a body movement" can refer to such a rotation speed (angular velocity) or change in the rotation angle.

[0059] The processor 340 controls the overall operation of the wearable device 300. The processor 340 can be a part of a controller, which can include processing circuitry such as hardware including logic circuitry; a hardware / software combination such as a processor executing software; or a combination thereof. For example, the processing circuitry can include, without limitation, a central processing unit (CPU), an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a programmable logic unit, a microprocessor, an application specific integrated circuit (ASIC), etc.

[0060] The processor 340 can include one or more dedicated processors that stably generate a target exercise pattern by controlling the electrical connections in the motor driver circuit 320 based on the speed of the body movement of the user 100.

[0061] The memory 350 stores information or data required for the processor 340 to perform processing operations. For example, the memory 350 can store instructions to be executed by the processor 340. The memory 350 can include a random access memory (RAM), a dynamic random access memory (DRAM), a static random access memory (SRAM), or another type of nonvolatile memory known in the art.

[0062] The control operation of the wearable device 300 can be implemented by a control signal output from the processor 340. The processor 340 can generate a control signal for controlling the electrical connection in the motor driver circuit 320. When the wearable device 300 operates in the exercise mode, the processor 340 can control the switch connection in the motor driver circuit 320 based on the speed of the user's leg movement sensed by the sensor 330 to provide an exercise load to the user.

[0063] The control state of the switch connection in the motor driver circuit 320 can include a first control state in which the electrical connection in the motor driver circuit 320 is closed and a second control state in which the electrical connection in the motor driver circuit 320 is open. The processor 340 can provide an exercise load through the frame of the wearable device 300 according to the speed of the user's leg movement by controlling the ratio of each change between the first control state and the second control state. To form an exercise load, the processor 340 can control the control state of the motor driver circuit 320 so that the first control state and the second control state are periodically and alternately repeated. The first control state is a state in which the motor 310 is not connected to the battery 450 and the circuit including the motor 310, the switch 410, and the switch 420 forms an electrical closed loop. In the first control state, both terminals of the motor 310 are connected to each other so that the resistance in the closed loop including the motor 310, the switch 410, and the switch 420 is very low. (Since the voltage at both terminals of the motor 310 is the same, according to Ohm's law, the resistance in the closed loop can theoretically be "0".) In this circuit state, the characteristic of maintaining a very low resistance in the closed loop induces a force in a direction that does not generate an electromotive force even if the electromotive force is small. Here, the electromotive force is a voltage generated in the motor 310 when the motor 310 rotates. Therefore, a large rotational resistance can be generated to hinder the rotation of the motor 310. When the frame of the wearable device 300 moves by the body movement of the user wearing the wearable device 300, the movement of the frame is transmitted to the motor 310, and an electromotive force is generated in the motor 310. In this example, the motor driver circuit 320 is in a closed loop state so that a rotational resistance that is a resistance or a force that counteracts the electromotive force from the motor 310 is generated.

[0064] The outer frame of the wearable device 300 is worn on the user's body (e.g., leg) and moves in the same direction as the user's body, and the outer frame provides the user's body with a rotational resistance received from the motor 310. As described above, in the first control state, a great rotational resistance is generated in response to the user's body motion. When the user tries to move the body wearing the outer frame in this case, the rotational resistance acts on the body through the outer frame, and the user feels a strong resistance. The second control state is a state in which the connection in the circuit including the motor 310 is disconnected, and thus there is no electrical connection for the motor 310. In the second control state, no power or rotational resistance is generated, and thus the user feels minimal resistance.

[0065] The processor 340 can generate an exercise load by controlling the ratio of each change between the first control state and the second control state without driving the motor 310 using the power of the battery. In another example embodiment, in addition to generating an exercise load by controlling the ratio of each change between the first control state and the second control state, the processor 340 can control the motor 310 to generate a torque in a direction that hinders the user's leg motion by supplying power of the battery to the motor 310. In response to the determination that it is difficult to achieve a target exercise load due to the rotational resistance caused by controlling the electrical connection in the motor driver circuit 320, the processor 340 can drive the motor 310 to generate a torque to hinder the leg motion.

[0066] The processor 340 can control the size of the exercise load by adjusting the control ratio between the duration of the first control state and the duration of the second control state in one repetition cycle. The control signal for adjusting the control ratio can be implemented, for example, in the form of a pulse width modulation (PWM) signal, which is a signal that can determine the control state according to the duty ratio of the signal pulse width. In this case, the high level value of the PWM signal can correspond to the first control state, and the low level value of the PWM signal can correspond to the second control state. In general, the exercise load applied to the user increases as the proportion of the first control state to the second control state in a single cycle increases. In addition, the exercise load increases as the speed of the user's leg motion increases.

[0067] When the user exercises while moving his leg, the user's leg movement speed can vary over time. Even without considering the electrical connection in the motor driver circuit 320, the user can feel different exercise loads according to the leg movement speed when the leg movement speed varies over time. For example, in the case where the ratio between the first control state and the second control state is fixed, the user can feel a relatively large exercise load when the user's leg movement speed increases. A large change in the leg movement speed can cause a sharp change in the exercise load, which can cause discomfort to the user. In controlling the motor driver circuit 320 in which the motor driver circuit 320 controls the electrical connection around the motor 310, the processor 340 can suppress (or optionally, prevent) the generation of an unintended size of the exercise load according to the leg movement speed by adjusting the ratio between the duration of the first control state and the duration of the second state, taking into account the user's leg movement.

[0068] In an example embodiment, the processor 340 can determine the speed of the user's leg movement based on the angular velocity information of the leg movement received from the sensor 330, and control the motor driver circuit 320 based on the target exercise load to be provided to the user and the determined speed of the leg movement. The electrical connection in the motor driver circuit 320 can be adjusted according to the change in the speed of the leg movement over time. In order to provide the same exercise load to the user, the control ratio, which is the ratio between the duration of the first control state and the duration of the second control state after the first control state, can be adjusted according to the leg movement speed. For example, if the speed of the user's leg movement changes from a first speed to a second speed, the processor 340 can adjust the ratio between the duration of the first control state and the duration of the second control state to correspond to the second speed. If the second speed is greater than the first speed (i.e., if the speed of the leg movement is faster than before), the processor 340 can adjust the control ratio by reducing the duration of the first control state and increasing the duration of the second control state. Conversely, if the second speed is less than the first speed (i.e., if the speed of the leg movement is slower than before), the processor 340 can adjust the control ratio by increasing the duration of the first control state and reducing the duration of the second control state.

[0069] Assuming that the control signal is implemented in the form of a PWM signal, and the wearable device 300 aims to apply the same size of exercise load to the user's body over time, if the speed of the user's leg movement is faster than before, the processor 340 can decrease the ratio of the value maintained at the high level and increase the ratio of the value maintained at the low level within each cycle of the PWM signal. Conversely, if the speed of the user's leg movement is slower than before, the processor 340 can increase the ratio of the value maintained at the high level and decrease the ratio of the value maintained at the low level within each cycle of the PWM signal.

[0070] The relationship between the leg movement speed of the user, the control ratio between the duration of the first control state and the duration of the second control state, and the magnitude (or intensity) of the exercise load can be determined (or alternatively, predetermined) by a control model. Information about the control model can be stored in the memory 350.

[0071] In advance, a torque value corresponding to the exercise load can be measured by a torque sensor configured to measure the torque at a given desired (or alternatively, predetermined) control ratio applied to the motor driver circuit 320 and a desired (or alternatively, predetermined) rotational speed corresponding to various leg movement speeds of the user. By performing this measurement process for various rotational speeds and various control ratios, data about the exercise load level for each rotational speed and control ratio can be collected. A control model for defining the relationship between the leg movement speed, the control ratio, and the magnitude of the exercise load can be generated based on the collected data, and the control model can output a value of the control ratio that needs to be set for generating the target exercise load at a given speed of the current leg movement. The ratio between the duration of the first control state and the duration of the second control state can be determined from the output value. The control model can be defined by, for example, a mapping table or a relational expression. For example, the value of the control ratio set according to each defined leg movement speed and the magnitude (or intensity) of the exercise load can be determined in advance and defined in the form of a mapping table. The relationship between the corresponding desired (or alternatively, predetermined) values of the leg movement speed, the control ratio, and the target exercise load can be defined by the mapping table, and other values can be determined by a proportional expression. For example, the mapping table can be defined as shown in Table 1 below.

[0072] [Table 1]

[0073]

[0074]

[0075] In Table 1, V1, V2, …, Vn correspond to different leg movement speeds, and T1, T2, …, Tn correspond to different target exercise loads. P1, P2, …, Pn are values of the control ratio (the ratio between the duration of the first control state and the duration of the second control state) set for the user to feel the target exercise load when given the leg movement speed and the target exercise load.

[0076] As another example, a relational expression in which the leg movement speed and the magnitude (or strength) of the exercise load are independent variables and the value of the control ratio is a dependent variable can be defined in advance. When the target exercise load and the leg movement speed are input to the relational expression, the relational expression can provide the value of the control ratio (the ratio between the duration of the first control state and the duration of the second control state) that needs to be set for the user to feel the target exercise load.

[0077] The processor 340 can determine the ratio between the duration of the first control state and the duration of the second control state to be applied to the motor driver circuit 320 based on the target exercise load to be provided to the user and the leg movement speed of the user based on the control model described above. The magnitude (or intensity) of the target exercise load can be set by the user, or can be set in real time according to the user's exercise state or a time determined (or optionally, predetermined) by the processor 340 executing software configured to manage an exercise program (a program configured to adjust the exercise intensity according to the type and time of exercise) for assisting the user in exercising in the middle of the exercise. The processor 340 can control the electrical connection in the motor driver circuit 320 based on the determined control ratio, thereby providing the user with the target exercise load of the originally intended magnitude regardless of the current leg movement speed of the user.

[0078] Figure 5 A control operation of a processor according to an example embodiment is illustrated.

[0079] Referring to Figure 5 , the processor 340 can control the motor driver circuit 320 based on the control signals. In this example, it is assumed that the motor driver circuit 320 includes an H-bridge circuit configured to control the electrical connection through a plurality of switches 410, 420, 430, and 440. The processor 340 can control the states (on or off) of the first switch 410, the second switch 420, the third switch 430, and the fourth switch 440 based on the first control signal, the second control signal, the third control signal, and the fourth control signal, respectively.

[0080] The processor 340 can generate an exercise load by controlling the electrical connections in the motor driver circuit 320 without supplying power from the battery 450 to the motor 310. The processor 340 can disconnect the electrical connection between the battery 450 and the motor 310 by turning off the third switch 430 and the fourth switch 440 via the third control signal and the fourth control signal, and continuously maintain the disconnected state. In the state where the electrical connection between the battery 450 and the motor 310 is disconnected by turning off the third switch 430 and the fourth switch 440, the processor 340 can generate an exercise load by controlling the first control state 510 and the second control state 520 to be repeatedly alternated for the motor driver circuit 320. In the first control state 510, the first switch 410 and the second switch 420 are turned on by the first control signal and the second control signal, whereby the electrical connections in the motor driver circuit 320 form a closed loop. In the second control state 520, the first switch 410 and the second switch 420 are turned off by the first control signal and the second control signal, whereby the electrical connections in the motor driver circuit 320 form an open loop. As described above, in the first control state 510, a large rotational resistance is generated in the motor 310, so that the user feels a large resistance in the direction opposite to the direction of the leg. In the second control state 520, no power or rotational resistance is generated, so that the user feels a minimum resistance.

[0081] The processor 340 can adjust the magnitude of the resistance by adjusting the ratio between the duration of the first control state 510 and the duration of the second control state 520. For example, the magnitude of the resistance felt by the user can increase as the proportion of the duration of the first control state 510 within each repetition time period increases. Conversely, the magnitude of the resistance felt by the user can decrease as the proportion of the duration of the second control state 520 increases.

[0082] Figure 6A 、 Figure 6B and Figure 6C shows a control operation of a processor according to leg movement of a user according to an example embodiment.

[0083] The processor 340 can adaptively perform the control operation described with reference to Figure 5 to the leg movement of a user wearing the wearable device 600. Figure 6A and Figure 6B is an example of control of the wearable device 600 for the left leg 610, and Figure 6C is an example of control of the wearable device 600 for the right leg 650. For ease of description, it is assumed that the leg movement speed of the user is relatively fast in the example of Figure 6A and Figure 6C , and the leg movement speed of the user is relatively slow in the example of Figure 6B . In addition, in the examples of Figure 6A andFigure 6B In the example of FIG. 6, assume that the wearable device 600 is intended to provide the same size of target exercise load to the user.

[0084] In Figure 6A In the example of FIG. 6, the processor 340 can control the switch 410 and the switch 420 included in the motor driver circuit 320 based on the control signal 620 in the form of a PWM signal. The control signal 620 having the same signal waveform can be provided to the switch 410 and the switch 420. The switch 410 and the switch 420 are turned on at a high level value 622 of the control signal 620 and turned off at a low level value 624 of the control signal 620. During this control operation, the switch 430 and the switch 440 remain turned off. When the control signal 620 has the high level value 622, the electrical connection in the motor driver circuit 320 forms the first control state 510 of a closed loop is activated. When the control signal 620 has the low level value 624, the electrical connection in the motor driver circuit 320 forms the second control state 520 of an open loop is activated. The value of the control signal 620 is periodically and repeatedly changed. Accordingly, the first control state 510 and the second control state 520 are alternately repeated at a desired (or optionally, predetermined) interval. The control signal 620 in the form of a PWM signal has a period that is repeated in units of hertz (Hz). As an example, the control signal 620 can control the change between the first control state 510 and the second control state 520 at a frequency of 40 kHz.

[0085] In Figure 6B In the example of FIG. 6, the processor 340 can control the switch 410 and the switch 420 included in the motor driver circuit 320 based on the control signal 640. The control signal 640 having the same signal waveform is provided to the switch 410 and the switch 420. The switch 410 and the switch 420 are turned on at a high level value 642 of the control signal 640 and turned off at a low level value 644 of the control signal 640. Similar to Figure 6A In the example of FIG. 6, the value of the control signal 620 is periodically and repeatedly changed such that the first control state 510 and the second control state 520 are alternately repeated at a desired (or optionally, predetermined) interval.

[0086] As described above, if the speed of the user's leg movement becomes relatively slow, the user feels a relatively small exercise load. Accordingly, in order to maintain the exercise load at the intended size, it is necessary to increase Figure 6AThe ratio of the durations of the first control state 510 and the second control state 520 is such that the user can feel a relatively large exercise load. In consideration of the relationship in which the size of the exercise load felt by the user varies according to the ratio of the durations of each of the first control state 510 and the second control state 520, by appropriately adjusting the duration of each of the first control state 510 and the second control state 520 according to the speed of the leg movement of the user, a desired (or alternatively, predetermined) size of exercise load can be provided to the user.

[0087] Assuming that the sensor 330 configured to sense the leg movement in the wearable device 600 is an encoder, the sensor 330 can sense a change in the rotation angle of the leg over time and transmit the sensed information as a bit value to the processor 340. The processor 340 can estimate the rotation angle of the leg movement based on the received bit value, and estimate the speed of the leg movement based on the change in the rotation angle over time. The processor 340 can provide a desired (or alternatively, predetermined) size of exercise load to the user by adjusting the ratio of the durations of the first control state 510 based on the estimated speed of the leg movement. For example, assuming that the speed of the leg movement of the user is relatively fast at the start, as in the example of Figure 6A , then becomes slower, as in the example of Figure 6B , the processor 340 can adjust the control signal from the signal waveform as in the first control signal 620 to the signal waveform as in the second control signal 640, so that the ratio of the durations of the first control state 510 and the second control state 520 can relatively increase. If the desired (or alternatively, predetermined) control operation is not performed as the speed of the leg movement of the user decreases, the size of the exercise load felt by the user can decrease. However, in this case, the processor 340 can compensate for the decrease in the size of the exercise load that the user can feel by controlling the ratio of the durations of the first control state 510 to increase, so that the user can feel a desired (or alternatively, predetermined) size of exercise load.

[0088] As another example, when the speed of the leg movement of the user is relatively slow at the start, as in the example of Figure 6B , then becomes faster, as in the example of Figure 6A , if the user targets Figure 6B(The processor 340 can adjust the control signal from a waveform such as the second control signal 640 to a waveform such as the first control signal 620, so that the ratio of the duration of the first control state 510 to the duration of the second control state 520 can be relatively reduced. If the desired (or optionally, predetermined) control operation is not performed when the speed of the user's leg movement increases, the magnitude of the exercise load perceived by the user may unintentionally increase. However, in this case, the processor 340 can compensate for the possible increase in the magnitude of the exercise load perceived by the user by controlling the reduction of the ratio of the duration of the first control state 510, so that the user perceives a predetermined magnitude of exercise load.)

[0089] Reference Figure 6C For example, the processor 340 can be controlled separately for the user's left leg 610 and right leg 650 to provide exercise load. Therefore, the magnitude of the exercise load applied to the right leg 650 and the control signal may differ from the magnitude of the exercise load applied to the left leg 610 and the control signal (first control signal 620). In the third control signal 660 for providing exercise load to the right leg 650, the ratio between the duration of the state with a high level value 662 and the duration of the state with a low level value 664 may differ from the ratio in the control signal (first control signal 620) for providing exercise load to the left leg 610.

[0090] Figure 7 and Figure 8 The variation in control operation of a wearable device according to an example embodiment of the change in leg movement speed is illustrated.

[0091] Figure 7 The variation of the exercise load based on the user's leg movement speed and control ratio is described, where the control ratio is the ratio between the duration of the first control state 510 and the duration of the second control state 520. Waveforms 710, 720, 730, and 740 correspond to different leg movement speeds, which are fixed values. The leg movement speed increases in the order of the first waveform 710, the second waveform 720, the third waveform 730, and the fourth waveform 740.

[0092] The control ratio can be expressed as a percentage. For example, a control ratio of 70% indicates that the duration of the first control state 510, in which the electrical connections in the motor driver circuit 320 form a closed loop, is 70% of the total duration, and the duration of the second control state 520, in which the electrical connections in the motor driver circuit 320 form an open loop, is 30% of the total duration.

[0093] Assuming the value of the control ratio remains the same, e.g., assuming the value of the control ratio is "A", it can be seen that the magnitude of the exercise load increases as the speed of the leg movement increases. Thus, if the user increases the walking speed while wearing the wearable device in an environment having a fixed control ratio, the magnitude of the exercise load felt by the user increases. Conversely, if the user decreases the walking speed in an environment having a fixed control ratio, the magnitude of the exercise load felt by the user decreases. In the case where the user desires a fixed target exercise load, changes in the walking speed of the user can result in changes in the exercise load, which can cause the user to feel uncomfortable.

[0094] Referring to Figure 8 , the processor 340 can appropriately adjust the control ratio according to changes in the speed of the leg movement of the user. The sensor 330 of the wearable device 110 can measure the leg movement of the user, and the processor 340 can estimate the speed of the leg movement (e.g., the rotational speed or angular velocity of the joint movement) based on the measured leg movement. The processor 340 can determine how to adjust the control ratio to provide the target exercise load using the control model stored in the memory 350 according to changes in the estimated speed of the leg movement. When a target exercise load is given and the speed of the leg movement is input into the control model, the control model can provide the control ratio for the motor driver circuit 320 to achieve the target exercise load.

[0095] Assuming that the value of the control ratio for providing the target exercise load is "B" when the speed of the leg movement of the user at a previous point in time is the speed 810 corresponding to the fourth waveform 740. Thereafter, if the speed of the leg movement of the user decreases to the speed 820 corresponding to the third waveform 730, the electromotive force of the motor 310 decreases in response to the speed 820, and the rotational resistance also decreases, so that the user feels an exercise load smaller than the target exercise load set for the speed 810 previously. In order to provide the same target exercise load as before to the user, the value of the control ratio should be increased to "C". The processor 340 can automatically increase the control ratio according to the decreased speed of the leg movement, thereby maintaining the target exercise load at a desired (or optionally, predetermined) magnitude. For example, in the example of FIG. 7, assuming that the speed of the leg movement of the user corresponds to the speed 810, and the processor 340 controls the motor driver circuit 320 based on the control signal 620. Thereafter, if the speed of the leg movement of the user decreases to the speed 820 slower than the previous speed 810, the processor 340 can change the control signal for the motor driver circuit 320 to the control signal 640 by increasing the ratio of the duration of the first control state 510 to the second control state 520 in the previous control signal 620. By this change in the control signal, the user can feel the same magnitude of the exercise load even when the speed of the leg movement of the user decreases. Figure 6A ​

[0096] Figure 9 FIG. 9 is a flowchart illustrating an operation method of a wearable device according to an example embodiment.

[0097] Referring to Figure 9 At operation 910, the sensor 330 senses a body motion of a user. Information about the body motion sensed by the sensor 330 can be transmitted to the processor 340, and the processor 340 can determine a speed of the body motion based on the information about the body motion. For example, information about a change in a rotational position and a rotational angle according to a leg motion of the user can be transmitted from the sensor 330 to the processor 340, and the processor 340 can calculate the speed of the body motion by processing the information received from the sensor 330.

[0098] At operation 920, the processor 340 sets a target exercise load to be provided to the user. The target exercise load can have a fixed or time-varying value. The target exercise load can be determined, for example, based on an exercise intensity selected by the user, or can be determined by the processor 340 executing software configured to adjust the size of the exercise load over time by an algorithm. Operations 910 and 920 can be performed in parallel, or can be sequentially performed in any order.

[0099] In some example embodiments, the wearable device 300 can further include a communicator configured to communicate with an external device (e.g., a remote controller). The remote controller can provide a user interface (UI) that enables operation or manipulation of the wearable device 300, and the user can control the functions and operations of the wearable device 300 through the UI. The remote controller can be controlled by the user, where the user can be a wearer of the wearable device 300 or a third party such as a therapist or a doctor. The user can set or adjust the target exercise load through the remote controller.

[0100] At operation 930, the processor 340 can generate a control signal for controlling the motor driver circuit 320 of the wearable device based on the speed of the sensed body motion. The processor 340 can determine the speed of the body motion based on the sensed body motion, and generate a control signal for adjusting a control ratio based on the determined speed, where the control ratio is a ratio between a duration of a first control state in which electrical connections in the motor driver circuit 320 are closed-loop and a duration of a second control state in which the electrical connections in the motor driver circuit 320 are open-loop. The control ratio can correspond to each change ratio between the first control state and the second control state. When the speed of the body motion changes, the processor 340 can generate a control signal for adjusting the control ratio to correspond to the changed speed of the body motion to provide the intended target exercise load.

[0101] As the speed of the body motion increases, the processor 340 can generate control signals to adjust the control ratio by reducing the duration of the first control state and increasing the duration of the second control state. Conversely, as the speed of the body motion decreases, the processor 340 can generate control signals to adjust the control ratio by increasing the duration of the first control state and reducing the duration of the second control state.

[0102] At operation 940, the processor 340 can control the electrical connections in the motor driver circuit 320 based on the control signals. The processor 340 can control the change between the first control state, in which the electrical connections in the motor driver circuit 320 are closed loop, and the second control state, in which the electrical connections in the motor driver circuit 320 are open loop. The processor 340 can control the electrical connections in the motor driver circuit 320 such that the first control state and the second control state can be repeated periodically and alternately, thereby providing an exercise load according to the speed of the body motion of the user through the frame connected to the motor 310.

[0103] In some example embodiments, the wearable device 300 can operate in a hybrid mode, in which the wearable device 300 automatically switches between controlling the motor 310 to provide resistance (as described above) and providing an assistive force to assist the user in walking. For example, in some example embodiments, the user can enter a particular muscle or exercise that the user wishes to focus on, and the processor 340 can selectively provide an exercise load during certain portions of the gait cycle corresponding to the muscle desired to be exercised to increase muscle strength or to recover the desired muscle, and can selectively provide an assistive force during other portions of the gait cycle to assist the user. For example, the hip muscles behind the user's knee and the hamstring muscles and the quadriceps muscles in front of the knee can be activated differently based on the gait phase, and the wearable device 300 can provide an exercise load during portions of the gait phase corresponding to the desired muscles.

[0104] The units described herein can be implemented using hardware components, software components, and / or combinations thereof. Processing devices can be implemented using one or more general-purpose or special purpose computers such as, for example, processors, controllers and arithmetic logic units (ALUs), DSPs, microcomputers, FPGAs, programmable logic units (PLUs), microprocessors, or any other device capable of responding to and executing instructions in a defined manner. Processing devices can run an operating system (OS) and one or more software applications running on the OS. Processing devices can also access, store, manipulate, process, and create data in response to the execution of software. For simplicity, the processing devices are described singularly; however, one skilled in the art will appreciate that the processing devices can include a plurality of processing elements and a plurality of types of processing elements. For example, the processing devices can include a plurality of processors or a processor and a controller. Additionally, different processing configurations are possible, such as parallel processors.

[0105] Software can include a computer program, a piece of code, an instruction, or some combination thereof, for independently or collectively instructing or configuring a processing device to operate as desired. Software and data can be embodied permanently or temporarily in any type of machine, component, physical or virtual equipment, computer storage medium or device, or spread across multiple entities. Software can also be distributed over network coupled computer systems so that software stored locally is executed remotely, or software stored remotely is executed locally, and / or any combination thereof. Software and data can be stored on one or more non-transitory computer-readable recording mediums.

[0106] The methods according to the above-described example embodiments can be recorded in non-transitory computer-readable media including program instructions to implement various operations of the above-described example embodiments. The non-transitory computer-readable media can further include, alone or in combination with the program instructions, data files, data structures, and the like. The program instructions recorded on the non-transitory computer-readable media can be specially designed and configured for the purposes of the example embodiments, or they can be of the kind well known and available to those having ordinary skill in the computer software field. Examples of non-transitory computer-readable media include magnetic media, such as hard disks, floppy disks, and magnetic tapes; optical media such as CD-ROM disks, DVDs, and / or Blu-ray disks; magneto-optical media, such as optical disks; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory (e.g., a USB flash drive, memory cards, a memory stick, and the like). Examples of program instructions include both machine code, such as produced by a compiler, and files containing a high-level code that can be executed by the computer using an interpreter. The above-described apparatus can be configured to function as one or more software modules in order to perform the operations of the above-described examples, and vice versa.

[0107] A number of example embodiments have been described. Nevertheless, it will be understood that various modifications can be made to the example embodiments. For example, suitable results can be achieved if the described techniques are performed in a different order and / or if components in the described systems, architectures, devices, or circuits are combined in a different manner and / or replaced or supplemented by other components or their equivalents.

[0108] Accordingly, other embodiments are within the scope of the following claims.

Claims

1. A wearable device configured to provide an exercise load to a user when worn on the user's body, the wearable device comprising: a frame configured to be worn on the user's body to support the body; a motor configured to be attached to the frame; a motor driver circuit connected to the motor; a sensor configured to sense a body motion of the user; and a processor configured to generate a control signal for controlling electrical connections in the motor driver circuit to provide the exercise load through the frame according to a speed of the body motion by controlling a ratio of each change between a first control state and a second control state based on the control signal, wherein the first control state is a state in which the electrical connections in the motor driver circuit are a closed loop in which two terminals of the motor are connected to each other, and the second control state is a state in which the electrical connections in the motor driver circuit are an open loop in which the connection of the motor is disconnected. The processor is further configured to periodically and alternately repeat switching between the first control state and the second control state based on the ratio of each change.

2. The wearable device of claim 1, wherein, The processor is further configured to, 3. The wearable device of claim 1, wherein, determine the speed of the body motion based on the body motion, and adjust the ratio of each change based on the speed of the body motion by adjusting the ratio of each change between a duration of the first control state and a duration of the second control state to correspond to a second speed if the speed of the body motion changes from a first speed to the second speed. The processor is further configured to adjust the ratio of each change by:

4. The wearable device of claim 3, wherein, decreasing the duration of the first control state and increasing the duration of the second control state if the second speed is greater than the first speed, and increasing the duration of the first control state and decreasing the duration of the second control state if the second speed is less than the first speed. The processor is further configured to, 5. The wearable device of claim 3, wherein, receive an input of a target exercise load from the user, and adjust the ratio of each change based on the target exercise load and the speed of the body motion. The processor is further configured to generate the exercise load by driving the motor without using power of a battery by forming a closed loop in the first control state.

6. The wearable device of claim 1, wherein, The processor is further configured to control the motor to generate a torque in a direction that hinders the body motion by supplying power of a battery to the motor, and to generate the exercise load by controlling a change between the first control state and the second control state.

7. The wearable device of claim 1, wherein, The motor driver circuit comprises:

8. The wearable device of claim 1, wherein, a plurality of switches configured to control electrical connections in the motor driver circuit based on the control signal. The wearable device is configured to be worn on a lower body of the user to provide resistance to the lower body of the user.

9. The wearable device of claim 1, wherein, 10.A method of operating a wearable device configured to provide an exercise load to a user when worn on the user's body, the wearable device comprising a frame configured to be worn on the user's body and a motor configured to be attached to the frame, the method comprising: ​ sensing a body motion of the user via a sensor; and generating a control signal for controlling an electrical connection in a motor driver circuit of the wearable device based on a speed of the body motion to provide the exercise load through the frame according to the speed of the body motion by controlling a change ratio per time between a first control state and a second control state based on the control signal, wherein the first control state is a state in which the electrical connection in the motor driver circuit is a closed loop in which both terminals of the motor are connected to each other, and the second control state is a state in which the electrical connection in the motor driver circuit is an open loop in which the connection of the motor is disconnected.

11. The method of claim 10, wherein, The generating the control signal includes generating a control signal for periodically and alternately repeating switching between the first control state and the second control state.

12. The method of claim 10, wherein, The generating the control signal includes: determining the speed of the body motion based on the body motion; and in response to the speed of the body motion changing from a first speed to a second speed, generating a control signal for adjusting the change ratio per time based on the speed of the body motion by adjusting the change ratio per time between a duration of the first control state and a duration of the second control state to correspond to the second speed.

13. The method of claim 12, wherein, The generating the control signal includes, in response to the second speed being greater than the first speed, generating a control signal for adjusting the change ratio per time by decreasing the duration of the first control state and increasing the duration of the second control state.

14. The method of claim 12, wherein, The generating the control signal includes, in response to the second speed being less than the first speed, generating a control signal for adjusting the change ratio per time by increasing the duration of the first control state and decreasing the duration of the second control state. 15.A non-transitory computer-readable storage medium storing instructions which, when executed by a processor, cause the processor to perform the method of claim 10.

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