Systems and methods for adding or subtracting energy to body motion

A method of making a phase oscillating device, comprising:

• providing a sensor;
• measuring a physical state of a primary body of a user using the sensor;
• determining a phase angle of the primary body of the user based on the physical state;
• filtering the phase angle of the primary body of the user;
• and
• triggering an actuator based on the phase angle of the primary body of the user to oscillate a force or a torque applied to the primary body of the user.

A phase oscillating device, comprising:

• a primary body of a user;
• a sensor coupled to the primary body of the user;
• a controller coupled to the sensor to determine a phase angle of the primary body of the user;
• and
• an actuator coupled to the controller to oscillate a signal to the actuator based on a trigonometric function of the phase angle of the primary body of the user.

A method of making a phase oscillating device, comprising:

• providing a sensor;
• measuring a physical state of a primary body of a user using the sensor;
• determining a phase angle of the primary body of the user based on the physical state;
• coupling an actuator to the primary body of the user;
• and
• triggering the actuator based on a trigonometric function of the phase angle of the primary body of the user to provide a force or a torque to assist movement of the primary body of the user.

A method of making a phase oscillating device, comprising:

• providing a sensor;
• measuring a physical state of a primary body of a user using the sensor;
• determining a phase angle of the primary body of the user based on the physical state;
• filtering the phase angle using a trigonometric function;
• producing a signal based on the filtered phase angle;
• and
• controlling an actuator based on the signal.