Pied (anatomie humaine) | EPFL Graph Search

Le pied est la partie distale du membre inférieur de l'être humain. Il est relié à la jambe par l'articulation de la cheville. Il supporte le poids du corps en position debout et permet la locomotion. Premier élément au contact avec le sol , Il assure un rôle essentiel dans l'équilibre, l'amortissement et la propulsion. Le pied adulte comprend , , assurant leur protection et limitant la mobilité, qui permettent leur mouvement. Une des spécialités paramédicales s'occupant du pied est la podologie, les praticiens sont appelés pédicures-podologues(ils réalisent notamment les semelles orthopédiques), orthopédistes-orthésistes (réalisent les semelles orthopédiques, les orthèses sur mesure et les orthoplasties) ou podo-orthésistes (réalisent l'appareillage : chaussures orthopédiques, semelles orthopédiques, orthoplasties, etc.). Les médecins spécialisés sont les podiatres (Canada et États-Unis), les rhumatologues, ou encore les chirurgiens orthopédistes et traumatologues. Origin

Foot-Interfaces Control and Human-Robot Interaction in Four-Handed Manipulation

Jacob Hernandez Sanchez

Humans have a great capacity to perform complex manipulations. However, there are many tasks for which two hands are not enough, such as in surgery. For such tasks, a dyad of people is required. However, when not used to work together, a dyad collaboration can be intermittent, slow and prone to misunderstandings if relied solely on verbal cues. The current PhD thesis report concerns the design and control of foot interfaces to enable solo four-handed manipulations. In the first part, we present the platform design in five DoF, with position mapping and haptic force feedback. We tackle the known issue of fatigue when using position mapping, by partially compensating for the dynamics of the leg. Finally, we perform a series of feasibility validations on bipedal teleoperation in 3 and 4 and 5 DoF. In the second part, a behavioural study investigates a symmetric bipedal holding and transport of an object while working on it with the hands. This study sheds light to the human capacity to use the redundancy given by augmentation with the feet, to assist the task of the hands. We investigate the effect of shared-control for lower limb teleoperation. Two modalities are used: 1. synergistic control of two robotic arms with one foot, 2. force assistance. We evaluate these strategies in terms of objective and subjective metrics, such as physical and cognitive workload and fluency.Aiming at enabling individualized foot dexterous control, in the third part of the thesis, we addressed the problem of bio-mechanical coupling of foot rotations. This is done by detecting intention to grasp, and selectively easing this action while haptically constraining the foot gestures for tool alignment. A user study was conducted to evaluate our proposed approach in a surgical laparoscopic gripper.In the fourth and final part, we focus on investigating more demanding tasks for the feet, as well as the coordinated control of four hands, during hybrid-robotic laparoscopic surgery. One foot controls a camera, while the other one performs a grasping task. Noteworthy is that all four-arms can be controlled simultaneously. For easing the solo surgical task, we design haptic assistance, for autonomous grasping operated by the foot. Finally, we perform a systematic behavioural study to understand the effect of our haptic-shared-control, along with an assistance modality for camera tool-tracking. We cover uni-pedal, bipedal and four-handed task scenarios. Our main conclusion is that foot gestures can be conditioned with haptic feedback, to effectively control multiple degrees of freedom of a supernumerary robotic arm. Thereby enabling four-arm simultaneous manipulations. This is done specifically by leveraging 1. a foot kinesthetic haptic platform that allows for the use of two feet, 2. leg compensation, and virtual assistive impedance, which are useful to increase comfort and alleviate fatigue. 3. Hybridization of control mappings for foot gestures, with limited range of motion and oblique axes of rotation, 4. Haptic shared-control strategies for prehensile force assistance, coordination assistance, and DoF-individuation assistance. We found that robotic assistance is highly appreciated, and has an important role in simplifying four-handed tasks. Indeed, these are instrumental considerations to enable a more fluent, less demanding, and more performant interaction, in tasks where the feet are supplementing the task of hands.

EPFL2022

Towards a Passive Adaptive Planar Foot with Ground Orientation and Contact Force Sensing for Legged Robots

Klajd Lika, Laura Isabel Paez Coy

Adapting to the ground enables stable footholds in legged locomotion by exploiting the structure of the terrain. On that account, we present a passive adaptive planar foot with three rotational degrees of freedom that is lightweight and thus suited for highly dynamic legged robots. Its low laying pivot joint provides high stability towards kinking. Information about the relative foot sole pose, and accordingly, the ground orientation is gathered by inertial measurement units (IMUs) placed on the foot sole and the shank. A complementary filter is presented that fuses these orientation estimates with an angular encoder to obtain a drift-free relative foot sole pose. The passive adaptive planar foot has been tested and compared to the classical point foot design on a variety of terrains and shows superior traction performance, especially on compressible soils. Being mounted on the quadrupedal robot ANYmal, the foot provides a reliable contact detection based on the fusion of the built-in 6-axis force/torque transducer and the IMUs. This allows to walk and trot on uneven terrain, loose soils, as well as climbing up a ramp and stairs while keeping the entire foot sole in ground contact all the time.

2019

Sensory feedback restoration in leg amputees improves walking speed, metabolic cost and phantom pain

Federica Barberi, Dario Bortolotti, Silvestro Micera, Francesco Maria Petrini, Stanisa Raspopovic, Giacomo Valle

Conventional leg prostheses do not convey sensory information about motion or interaction with the ground to aboveknee amputees, thereby reducing confidence and walking speed in the users that is associated with high mental and physical fatigue(1-4). The lack of physiological feedback from the remaining extremity to the brain also contributes to the generation of phantom limb pain from the missing legs(5,)(6). To determine whether neural sensory feedback restoration addresses these issues, we conducted a study with two transfemoral amputees, implanted with four intraneural stimulation electrodes' in the remaining tibial nerve (ClinicalTrials. gov identifier NCT03350061). Participants were evaluated while using a neuroprosthetic device consisting of a prosthetic leg equipped with foot and knee sensors. These sensors drive neural stimulation, which elicits sensations of knee motion and the sole of the foot touching the ground. We found that walking speed and self-reported confidence increased while mental and physical fatigue decreased for both participants during neural sensory feedback compared to the no stimulation trials. Furthermore, participants exhibited reduced phantom limb pain with neural sensory feedback. The results from these proof-of-concept cases provide the rationale for larger population studies investigating the clinical utility of neuroprostheses that restore sensory feedback.

2019

Foot-Interfaces Control and Human-Robot Interaction in Four-Handed Manipulation

Jacob Hernandez Sanchez

EPFL2022