Hybrid terrain-adaptive lower-extremity systems

A method for discriminating between properties of terrain underlying a lower extremity prosthetic, orthotic, or exoskeleton apparatus to be worn by a wearer, the apparatus to comprise a foot member, a lower leg member, and an ankle joint for connecting the foot member to the lower leg member, the method comprising:

• determining an inertial pose trajectory, based on a wearer intent, of at least one location on or coupled to the apparatus within a swing phase of a gait cycle prior to foot strike, the inertial pose trajectory defined as a matrix comprising at least two of:
• an orientation component of the at least one location on or coupled to the apparatus, a translation component of the at least one location on or coupled to the apparatus, or a velocity component of the at least one location on or coupled to the apparatus;
• determining a foot slope based on the inertial pose trajectory;
• estimating a velocity vector attack angle of a portion of the apparatus during the same swing phase of the gait cycle prior to foot strike based at least in part on the inertial pose trajectory;
• determining whether the velocity vector attack angle lies within a predetermined range;
• determining a property of an underlying terrain based on:
• a determination that the velocity vector attack angle lies within the predetermined range, and
• the foot slope;
• adjusting at least one of joint impedance or ankle angle equilibrium during the same swing phase of the gait cycle prior to foot strike based on the property;
• and
• adjusting at least one of the impedance or the ankle angle equilibrium to minimize a projected force imparted on the lower leg member during a period of time between when the foot member strikes the underlying terrain to when the foot member is positioned in a flat-foot position relative to the underlying terrain.

A method for controlling at least one of joint impedance, position or torque of a lower extremity prosthetic, orthotic, or exoskeleton apparatus to be worn by a wearer, the apparatus to comprise a foot member, a lower leg member, and an ankle joint for connecting the foot member to the lower leg member, the method comprising:

• determining an inertial pose trajectory, based on a wearer intent, of at least one location on or coupled to the apparatus within a swing phase of a gait cycle prior to foot strike, the inertial pose trajectory defined as a matrix comprising at least two of:
• an orientation component of the at least one location on or coupled to the apparatus, a translation component of the at least one location on or coupled to the apparatus, or a velocity component of the at least one location on or coupled to the apparatus;
• determining a foot slope based on the inertial pose trajectory;
• estimating a velocity vector attack angle of a portion of the apparatus during the same swing phase of the gait cycle prior to foot strike based at least in part on the inertial pose trajectory;
• determining whether the velocity vector attack angle lies within a predefined range;
• adjusting a joint position of the foot member or an ankle angle of the apparatus within the same swing phase of the gait cycle prior to foot strike to a toe down position based on:
• a determination that the velocity vector attack angle lies within a predefined range;
• and
• the foot slope;
• and
• adjusting at least one of an impedance or an ankle angle equilibrium of the apparatus to minimize a projected force imparted on the lower leg member during a period of time between when the foot member strikes the underlying terrain to when the foot member is positioned in a flat-foot position relative to the underlying terrain.

A method for discriminating between properties of terrain underlying a lower extremity prosthetic, orthotic, or exoskeleton apparatus to be worn by a wearer, the apparatus to comprise a foot member, a lower leg member, and an ankle joint for connecting the foot member to the lower leg member, the method comprising:

• determining an inertial pose trajectory, based on a wearer intent, of at least one location on or coupled to the apparatus within a swing phase of a gait cycle prior to foot strike, the inertial pose trajectory defined as a matrix comprising at least two of:
• an orientation component of the at least one location on or coupled to the apparatus, a translation component of the at least one location on or coupled to the apparatus, or a velocity component of the at least one location on or coupled to the apparatus;
• determining a foot slope based on the inertial pose trajectory;
• estimating a velocity vector attack angle of a portion of the apparatus during the same swing phase of the gait cycle prior to foot strike based at least in part on the inertial pose trajectory;
• determining whether the velocity vector attack angle lies within a predetermined range;
• determining a property of an underlying terrain based on:
• a determination that the velocity vector attack angle lies within the predetermined range, and
• the foot slope;
• controlling at least one of joint impedance, ankle angle equilibrium or joint torque of the apparatus during the same swing phase of the gait cycle prior to foot strike based on the property;
• and
• adjusting at least one of the joint impedance or the ankle angle equilibrium of the apparatus to minimize a projected force imparted on the lower leg member during a period of time between when the foot member strikes the underlying terrain to when the foot member is positioned in a flat-foot position relative to the underlying terrain.