DEVICES, SYSTEMS, AND METHODS TO MONITOR AND CHARACTERIZE THE MOTIONS OF A USER VIA FLEXIBLE CIRCUITS

1 . (canceled)

2 . A system configured to control a robotic device based on motions of a user, the system comprising:

a wearable article configured to be worn about a body portion of the user, the body portion comprising a joint or appendage, the wearable article comprising:

a tubular body comprising a resilient material; and

a flexible circuit coupled with the tubular body, the flexible circuit comprising a fluid-phase conductor configured to deform in response to a motion of the body portion and to generate a first signal that varies based on deformation of the fluid-phase conductor;

a communication interface configured to communicate with the robotic device; and

a processor communicably coupled to the flexible circuit and the communication interface, wherein the processor is configured to:

receive the first signal from the flexible circuit;

determine a first electrical parameter associated with the flexible circuit based on the first signal;

correlate the first electrical parameter to a first physical parameter associated with the flexible circuit or the body portion;

determine, based at least in part on the correlation, a real-time motion representation of the joint or appendage, the real-time motion representation

comprising at least one of a real-time position, a real-time angle, a rate of movement, or a motion trajectory of the joint or appendage; and

transmit, via the communication interface, a control signal configured to cause at least one movable portion of the robotic device to assume an actuated position or follow a motion trajectory corresponding to the real-time motion representation.

3 . The system of claim 2 , wherein the wearable article is configured as a joint monitoring sleeve.

4 . The system of claim 2 , further comprising the robotic device, wherein the robotic device is communicably coupled to the communication interface and configured to actuate the at least one movable portion in response to receiving the control signal, and wherein the at least one movable portion is configured as an artificial reproduction of the joint or appendage of the user.

5 . The system of claim 2 , wherein the robotic device comprises a robotic appendage or a prosthetic device.

6 . The system of claim 2 , wherein the joint or appendage comprises one of a knee, an elbow, a shoulder, a wrist, an ankle, a hip, an arm, a leg, a finger, a toe, a neck, a back, a hand, or a foot.

7 . The system of claim 2 , wherein the fluid-phase conductor comprises a conductive gel comprising a eutectic gallium alloy and a gallium oxide.

8 . The system of claim 7 , wherein the eutectic gallium alloy comprises gallium and indium, or gallium, indium, and tin.

9 . The system of claim 2 , wherein the first electrical parameter comprises at least one of a resistance, an impedance, an inductance, a capacitance, a voltage drop, or an electromagnetic field, and wherein the first physical parameter comprises at least one of a strain, a stress, a pressure, a dimension, a position, an angle, or a rate of movement.

10 . The system of claim 2 , wherein the flexible circuit comprises a plurality of traces formed of the fluid-phase conductor, the plurality of traces extending between one or more reference points and one or more anchor points on a medium of the flexible circuit, and wherein the processor is configured to determine a relative position of at least one reference point of the one or more reference points based on changes in the first electrical parameter across at least two traces of the plurality of traces.

11 . The system of claim 10 , wherein the processor is configured to repeatedly determine the relative position of each of a plurality of reference points to generate at least one of real-time motion capture data or a three-dimensional model of the body portion, and wherein the control signal is generated based at least in part on the real-time motion capture data or the three-dimensional model.

12 . The system of claim 2 , wherein the wearable article further comprises an inertial measurement unit (“IMU”) coupled to the resilient material and configured to generate a second signal, and wherein the processor is further configured to:

receive the second signal from the IMU;

determine a second electrical parameter associated with the IMU based on the second signal;

correlate the first electrical parameter to the second electrical parameter; and

modify a spatial position inferred from the second electrical parameter based on the correlation of the first electrical parameter to the second electrical parameter to correct drift in IMU-dependent information;

wherein the real-time motion representation is determined based at least in part on the modified spatial position.

13 . The system of claim 12 , wherein the IMU is a first IMU, the system further comprising a second IMU coupled to the resilient material, and wherein the flexible circuit is configured to extend across the joint between the first IMU and the second IMU.

14 . The system of claim 2 , wherein the wearable article further comprises a pressure sensor comprising a fluid-phase conductor and configured to generate a pressure signal, and wherein the processor is configured to generate the control signal based at least in part on the pressure signal to cause the robotic device to reproduce a contact state, a force state, or an object-interaction state represented by the pressure signal.

15 . The system of claim 14 , wherein the fluid-phase conductor of the pressure sensor is configured as an inductive pressure sensor.

16 . The system of claim 2 , wherein the communication interface comprises a wireless transmitter, and wherein the control signal is transmitted to the robotic device wirelessly.

17 . The system of claim 2 , wherein the processor is further configured to generate the control signal based at least in part on a stored correlation between a reference electrical parameter generated by the flexible circuit during a reference motion of the body portion and reference motion data associated with the reference motion.

18 . A method of controlling a robotic device based on motion of a user wearing a wearable article comprising a flexible circuit, the flexible circuit comprising a fluid-phase conductor, the method comprising:

obtaining, from the flexible circuit during performance of a first motion by a body portion of the user, a first electrical parameter associated with deformation of the fluid-phase conductor caused by the first motion;

obtaining reference data associated with performance of the first motion, the reference data comprising at least one of motion-capture data or a physical parameter associated with the first motion;

correlating, by a processor, the first electrical parameter with the reference data to generate a stored correlation;

storing the stored correlation in a memory communicably coupled to the processor; obtaining, from the flexible circuit during performance of a subsequent motion by the body portion, a subsequent electrical parameter associated with deformation of the fluid-phase conductor caused by the subsequent motion;

determining, based at least in part on the stored correlation and the subsequent electrical parameter, a real-time motion representation of the body portion; and

generating and transmitting, based at least in part on the real-time motion representation, a control signal to the robotic device, wherein the control signal is configured to cause the robotic device to replicate at least a portion of the subsequent motion.

19 . The method of claim 18 , wherein the reference data comprises motion-capture data generated by a camera or motion-capture device during the performance of the first motion.

20 . The method of claim 18 , wherein the reference data comprises a physical parameter associated with the first motion, the physical parameter comprising at least one of a strain, a stress, a pressure, a dimension, a position, an angle, or a rate of movement.

21 . The method of claim 18 , further comprising repeating the obtaining, correlating, and storing steps for a plurality of motions to generate a plurality of stored correlations corresponding to a range of motion of the body portion.

22 . The method of claim 18 , further comprising:

receiving inertial-measurement-unit (“IMU”) data from an IMU coupled with the wearable article;

correlating the IMU data with the subsequent electrical parameter; and

generating corrected IMU-dependent information based on the correlation;

wherein the control signal is generated based at least in part on the corrected IMU-dependent information.

23 . The method of claim 18 , further comprising receiving pressure-sensor data from a pressure sensor coupled with the wearable article and comprising a fluid-phase conductor, wherein generating the control signal comprises generating the control signal based at least in part on the pressure-sensor data to cause the robotic device to reproduce a contact state, a force state, or an object-interaction state represented by the pressure-sensor data.

24 . A wearable article configured to control a robotic device based on motions of a user, the wearable article comprising:

a tubular body comprising a resilient material, the tubular body configured to be worn about a body portion of the user comprising a joint or appendage;

a flexible circuit coupled with the tubular body, the flexible circuit comprising a fluid-phase conductor configured to deform in response to a motion of the body portion and to generate a first signal that varies based on deformation of the fluid-phase conductor;

an inertial measurement unit (“IMU”) coupled to the resilient material and configured to generate a second signal; and

a communication interface configured to communicate with the robotic device, wherein the flexible circuit and the IMU are communicably coupled to a processor via a plurality of conductive traces comprising the fluid-phase conductor, the processor coupled to the communication interface and configured to:

determine a first electrical parameter associated with the flexible circuit based on the first signal;

determine a second electrical parameter associated with the IMU based on the second signal;

correlate the first electrical parameter to a physical parameter;

determine, based at least in part on the correlation, a real-time motion representation of the joint or appendage; and

transmit, via the communication interface, a control signal configured to cause the robotic device to assume an actuated position or follow a motion trajectory corresponding to the real-time motion representation.

25 . The wearable article of claim 24 , further comprising a pressure sensor comprising a fluid-phase conductor, wherein the fluid-phase conductor of the pressure sensor is configured as an inductive pressure sensor.