Motor optimization process for lower limb exoskeleton
Introduction
Method that defines how to determine and apply the torque provided by the motorized joints of an exoskeleton of the lower limbs, during the various phases of walking of a subject with locomotor deficiency, helping his rehabilitation exercises. The gait analysis consist by measuring the distance along the sagittal plane between the patient’s feet through the motorized joints.

Technical features
Exoskeletons can be a valuable tool compared to traditional rehabilitation, allowing the patient to walk independently, for longer periods of time and following correct trajectories. There are several exoskeletons on the market that plan to develop assistive control strategies with different approaches, methods and outcomes. However, state-of-the-art systems generally do not provide assistance to the oscillating leg, applying a control so that the presence of joints has no effect, neither assisting nor hindering the patient’s walking. This invention achieves the above-mentioned purposes by realizing a method in which the determination of the state of walk is performed by measuring the distance between the patient’s feet on the basis of a projection of the position of the feet on the sagittal axis, to identify a foot in the front position, a foot in the back position or feet in aligned position. In addition, the motorized articulations of the exoskeleton are configured to detect the distance, along the sagittal plane, between the subject’s feet. TRL=7.
Possible Applications
- Enhancement of neurorehabilitation outcome of patients affected by neurological diseases with motor deficits, especially in post-stroke patients
- Optimization of existing lower limb exoskeletons
Advantages
- Use of a single parameter for the identification of the three phases of walk, which also prevents incorrect identification of the phases themselves
- Simple but comprehensive approach for gait analysis
- No additional sensor required (in addition to angular encoders, already present in motorized joints)
- Adequate care for patients, making walking safer, even in case of possible trajectory changes during different walking phases