Walk and roll robot

A mobile robotic unit features a main body, a plurality of legs for supporting the main body on and moving the main body in forward and reverse directions about a base surface, and a drive assembly. According to an exemplary embodiment each leg includes a respective pivotal hip joint, a pivotal knee joint, and a wheeled foot adapted to roll along the base surface. Also according to an exemplary embodiments the drive assembly includes a motor operatively associated with the hip and knee joints and the wheeled foot for independently driving pivotal movement of the hip joint and the knee joint and rolling motion of the wheeled foot. The hip joint may include a ball-and-socket-type joint interconnecting top portion of the leg to the main body, such that the hip joint is adapted to pivot said leg in a direction transverse to a forward-and-reverse direction

Joint assembly

A joint assembly is provided which includes a drive assembly and a swivel mechanism. The drive assembly features a motor operatively associated with a plurality of drive shafts for driving auxiliary elements, and a plurality of swivel shafts for pivoting the drive assembly. The swivel mechanism engages the swivel shafts and has a fixable element that may be attached to a foundation. The swivel mechanism is adapted to cooperate with the swivel shafts to pivot the drive assembly with at least two degrees of freedom relative to the foundation. The joint assembly allows for all components to remain encased in a tight, compact, and sealed package, making it ideal for space, exploratory, and commercial applications

Directed flux motor

A directed flux motor described utilizes the directed magnetic flux of at least one magnet through ferrous material to drive different planetary gear sets to achieve capabilities in six actuated shafts that are grouped three to a side of the motor. The flux motor also utilizes an interwoven magnet configuration which reduces the overall size of the motor. The motor allows for simple changes to modify the torque to speed ratio of the gearing contained within the motor as well as simple configurations for any number of output shafts up to six. The changes allow for improved manufacturability and reliability within the design

Development of a Human Machine Interface for a Wearable Exoskeleton for Users with Spinal Cord Injury

For millions of individuals, a spinal cord injury has taken away their ability to walk. While wheelchairs and leg braces offer mobility options, none offer a means to stand up and walk. For these individuals, secondary injuries can be prevalent, and special care must be taken to avoid the pain and cost of pressure sores, urinary tract infections, and other such ailments. Furthermore, there is an emotional benefit to being able to stand and walk. Events such as choosing your own seat at the theater or sports game, walking your daughter down the aisle at her wedding, reaching the pasta on the top shelf at the grocery store, or checking out of a hotel at the main counter, are taken for granted by those who can walk, but for those who use a wheelchair for mobility, these are stark reminders of the limitations of the chair. Exoskeletons provide a means by which these individuals can get up again and walk. They offer power joints and a support for the body so that a user with a spinal cord injury can rely on the robot's power to replace what their body no longer provides. While the architecture and design of such an exoskeleton is complex, the control of the exoskeleton offers numerous challenges. This thesis presents the development and testing of a method to allow the user to communicate his desired motion to the robot. For an exoskeleton to truly provide freedom for the user, the user must be able to operate the exoskeleton independently. To do this, the exoskeleton must know what the user wants to do and when and then decide if that maneuver is safe. The user communicates his desired action to the exoskeleton using the Human Machine Interface (HMI). This thesis describes development of the hardware and software for the HMI beginning with the conception of the structure of the HMI based on end-user surveys and observations of users. The hardware was then developed to determine the state transitions and the software was written to determine desired state changes. The Human Machine Interface was then verified using a mockup to test and then was tested on the eLEGS exoskeleton. The software was verified through experiments and theoretically using classifiers. The Human Machine Interface was tested by subjects with a wide range of injuries and abilities to ensure that it performed safely for all users. Based on experience with the Human Machine Interface, improvements in robustness and usability were made. This thesis also presents the development of some of the continuous controllers used to achieve the sitting and standing motions. While traditional control strategies rely on models, control of exoskeletons includes a human in the loop, which can be a sizeable disturbance. Therefore, the controller development must be robust to this disturbance and also take into account the comfort and safety of the user.The results presented here show numerous spinal cord injury patients of varying levels and completeness able to ambulate independently using the HMI developed for eLEGS. They are able to walk, sit, and stand naturally, thus providing wheelchair users a viable means of walking again

Experimental Protocol to Assess Neuromuscular Plasticity Induced by an Exoskeleton Training Session

Exoskeleton gait rehabilitation is an emerging area of research, with potential applications in the elderly and in people with central nervous system lesions, e.g., stroke, traumatic brain/spinal cord injury. However, adaptability of such technologies to the user is still an unmet goal. Despite important technological advances, these robotic systems still lack the fine tuning necessary to adapt to the physiological modification of the user and are not yet capable of a proper human-machine interaction. Interfaces based on physiological signals, e.g., recorded by electroencephalography (EEG) and/or electromyography (EMG), could contribute to solving this technological challenge. This protocol aims to: (1) quantify neuro-muscular plasticity induced by a single training session with a robotic exoskeleton on post-stroke people and on a group of age and sex-matched controls; (2) test the feasibility of predicting lower limb motor trajectory from physiological signals for future use as control signal for the robot. An active exoskeleton that can be set in full mode (i.e., the robot fully replaces and drives the user motion), adaptive mode (i.e., assistance to the user can be tuned according to his/her needs), and free mode (i.e., the robot completely follows the user movements) will be used. Participants will undergo a preparation session, i.e., EMG sensors and EEG cap placement and inertial sensors attachment to measure, respectively, muscular and cortical activity, and motion. They will then be asked to walk in a 15 m corridor: (i) self-paced without the exoskeleton (pre-training session); (ii) wearing the exoskeleton and walking with the three modes of use; (iii) self-paced without the exoskeleton (post-training session). From this dataset, we will: (1) quantitatively estimate short-term neuroplasticity of brain connectivity in chronic stroke survivors after a single session of gait training; (2) compare muscle activation patterns during exoskeleton-gait between stroke survivors and age and sex-matched controls; and (3) perform a feasibility analysis on the use of physiological signals to decode gait intentions