A GAIT CONTROLLED MOBILITY DEVICE
A mobility device comprising a motorized shoe to be worn by a user to increase the speed of walking. The motorized shoe has a plurality of wheels, with at least one wheel driven by an electric motor through a geartrain. On onboard controller gathers data from at least one of an inertial measurement unit, an ultrasonic sensor, and a vision system to generate a command speed to the electric motor. A user wearing a pair of the mobility devices, one on each foot, is able to walk with a normal gait, but at an increased speed.
1 . A method of controlling a mobility device, the method comprising:
receiving, using a processor, inertial data from an inertial measurement unit, wherein the inertial data comprises a plurality of data vectors;
determining, based on the inertial data, an estimated orientation of the mobility device;
transforming, using the processor, at least one of the plurality of data vectors from a local frame to a world frame;
identifying, based on the transformed data vector, at least one phase of a gait cycle;
determining, based on the at least one phase, a stride length; and
generating, based on the determined stride length, an output stride length.
2 . The method of claim 1 , further comprising: predicting, based on the inertial data, an estimated stride length before the end of a gait cycle using a machine learning module.
3 . The method of claim 1 , further comprising:
obtaining, from an ultrasonic sensor, ultrasonic data; and
modifying, based on the inertial data and the ultrasonic data, the stride length.
4 . The method of claim 1 , further comprising obtaining, using a de-drifting technique, a calibrated stride length.
5 . The method of claim 1 , further comprising mapping the stride length to a command speed.
6 . The method of claim 5 , further comprising:
obtaining, from a vision system, one or more images;
identifying, based on the one or more images, one or more obstacles, wherein the one or more obstacles are selected from the group consisting of: a static obstacle and a dynamic obstacle;
generating, based on the one or more obstacles, a response strategy; and
applying, based on the response strategy, an offset to the command speed of the mobility device.
7 . A mobility device adapted to be worn on the foot of a user comprising:
a rear chassis comprising:
a middle set of wheels; and
a rear set of wheels connected to an electric motor through a geartrain;
a front chassis comprising
a front set of wheels,
wherein the front chassis is connected to the rear chassis by a pivoting member; and
a control system configured to control the electric motor in response to an input from the user.
8 . The mobility device of claim 7 , wherein the control system comprises:
an inertial measurement unit and a processor.
9 . The mobility device of claim 7 , wherein the control system is housed in the rear chassis.
10 . The mobility device of claim 7 , wherein the middle set of wheels is connected by an axle, the axle having a width wider than a width of a user's foot.
11 . The mobility device of claim 10 , wherein the rear set of wheels is connected by an axle having a width smaller than the width of the axle connecting the middle set of wheels.
12 . The mobility device of claim 11 , wherein the front set of wheels is connected by an axle having a width smaller than the width of the axle connecting the rear set of wheels.
13 . The mobility device of claim 7 , further comprising one or more anti-reverse bearings associated with the front set of wheels.
14 . The mobility device of claim 7 , wherein the middle set of wheels and the rear set of wheels have a height greater than the height of the rear chassis.
15 . The mobility device of claim 7 , further comprising a mechanical brake connected to at least one of the front set of wheels, the middle set of wheels, or the rear set of wheels.
16 . The mobility device of claim 15 , wherein the mechanical brake is controlled by the control system.
17 . The mobility device of claim 15 , wherein the mechanical brake is controlled manually by a user.
18 . The mobility device of claim 7 , wherein the front chassis further comprises a rigid toe-cap.
19 . The mobility device of claim 7 , wherein the front chassis further comprises a semi-rigid toe-cap.