Vibro-tactile Haptic Guidance for Human-Robot Interaction and Cooperation tasks
Evaluation of a predictive approach in steering the human locomotion via haptic feedback
2015 IEEE/RSJ International Conference Intelligent Robots and Systems
In this paper, we present a haptic guidance policy to steer the user along predefined paths, and we evaluate a predictive approach to compensate actuation delays that humans have when they are guided along a given trajectory via sensory stimuli. The proposed navigation policy exploits the nonholonomic nature of human locomotion in goal directed paths, which leads to a very simple guidance mechanism. The proposed method has been evaluated in a real scenario where seven human subjects were asked to walk along a set of predefined paths, and were guided via vibrotactile cues. Their poses as well as the related distances from the path have been recorded using an accurate optical tracking system. Results revealed that an average error of 0.24 m is achieved by using the proposed haptic policy, and that the predictive approach does not bring significant improvements to the path following problem for what concerns the distance error. On the contrary, the predictive approach achieved a definitely lower activation time of the haptic interfaces.
Author = {Aggravi, M. and Scheggi, S. and Prattichizzo, D.},
Title = {Evaluation of a predictive approach in steering the human locomotion via haptic feedback},
BookTitle = {{Proc. IEEE/RSJ Int. Conf. Intelligent Robots and Systems}},
Address = {Hamburg, Germany},
Year = {2015}
Pages = {597--602},
Doi = {}, }
Haptic Wrist Guidance Using Vibrations for Human-Robot Teams
2016 IEEE International Symposium on Robot and Human Interactive Communication
Human-Robot teams can efficiently operate in several scenarios including Urban Search and Rescue (USAR). Robots can access areas too small or deep for a person, can begin surveying larger areas that people are not permitted to enter and can carry sensors and instruments. One important aspect in this cooperative framework is the way robots and humans can communicate during rescue operation. Vision and audio modalities may result not efficient in case of reduced visibility or high noise. A promising way to guarantee effective communications between robot and human in a team is the exploitation of haptic signals. In this work, we present a possible solution to let a robot guide the position of a human operator’s hand by using vibrations. We demonstrate that an armband embedding four vibrating motors is enough to guide the wrist of an operator along a predefined path or in a target location. The results proposed can be exploited in human-robot teams. For instance, when the robot detects the position of a sensible target, it can guide the wrist of the operator in such position following an optimal path.
Author = {Aggravi, M. and Salvietti, G. and Prattichizzo, D.},
BookTitle = {{Proc. IEEE International Symposium on Robot and Human Interactive Communication (Ro-Man)}},
Title = {{Haptic Wrist Guidance Using Vibrations for Human-Robot Teams}},
Address = {New York, USA},
Year = {2016},}
Cooperative human-robot haptic navigation
2014 IEEE International Conference on Robotics and Automation
This paper proposes a novel use of haptic feedback for human navigation with a mobile robot. Assuming that a path-planner has provided a mobile robot with an obstacle- free trajectory, the vehicle must steer the human from an initial to a desired target position by only interacting with him/her via a custom-designed vibro-tactile bracelet. The subject is free to decide his/her own pace and a warning vibrational signal is generated by the bracelet only when a large deviation with respect to the planned trajectory is detected by the vision sensor on-board the robot. This leads to a cooperative navigation system that is less intrusive, more flexible and easy-to-use than the ones existing in literature. The effectiveness of the proposed system is demonstrated via extensive real-world experiments.
Author = {Scheggi, S. and Aggravi, M. and Morbidi, F. and Prattichizzo, D.},
BookTitle = {{IEEE International Conference on Robotics and Automation (ICRA)}},
Title = {Cooperative human-robot haptic navigation},
Address = {Hong Kong, China},
Year = {2014},
Pages = {2693--2698}
Doi = {},}
Wearable Robotics and Assistive Devices
A remote vibrotactile guidance system for blind and visually impaired
2016, submitted to Transactions on Haptics.
Trained guide dogs and white canes still remain the primary mobility aids for visually impaired. However, they are limited in guiding the user toward a desired location, especially in unknown domains. In this paper we present a remote guidance system which provides the visually impaired with vibrotactile directional cues to properly move in environments in which they are not familiar with. The user is equipped with a webcam, two vibrotactile bracelets and a white cane which is used to avoid potential obstacles. The video captured by the webcam is streamed to a remote operator who can properly guide the impaired person by activating the vibrotactile stimulations. The proposed approach has been validated on a group of blind subjects in an outdoor urban scenario. Experimental results revealed that the proposed system can be an effective solution in terms of intuitiveness and acceptability.
DALI: A Smart Walking Assistant for Safe Navigation in Complex Indoor Environments
Book chapter Ambient Assisted Living, Volume 11 of the series Biosystems & Biorobotics
Indoor navigation can be a challenging issue for people afflicted by cognitive impairments. The project Devices for Assisted Living (DALi) is a research initiative sponsored by the European Commission under the FP7 programme with the goal of developing a robotic wheeled walker assisting disabled people in indoor scenarios where crowd, obstacles and multiple points of interest may confuse or in- timidate the users. The walking assistant, called c-Walker, is designed to monitor the environment, to detect possible hazards and to decide the best path across the space, thus guiding the user safely towards the wanted destination.
Author = {Aggravi, M. and Colombo, A. and Fontanelli, D. and Giannitrapani, A. and Macii, D. and Moro, F. and Nazemzadeh, P. and Palopoli, L. and Passerone, R. and Prattichizzo, D. and Rizano, T. and Rizzon, L. and Scheggi, S.},
Title = {A Smart Walking Assistant for Safe Navigation in Complex Indoor Environments},
BookTitle = {Ambient Assisted Living},
Pages = {487--497},
Publisher = {Springer International Publishing},
Year = {2015}
Robotic Manipulation
Object motion-decoupled internal force control for a compliant multifingered hand
2012 IEEE International Conference on Robotics and Automation
Compliance in multifingered hand improves grasp stability and effectiveness of the manipulation tasks. Compliance of robotic hands depends mainly on the joint control parameters, on the mechanical design of the hand, as joint passive springs, and on the contact properties. In object grasping the primary task of the robotic hand is the control of internal forces which allows to satisfy the contact constraints and consequently to guarantee a stable grasp of the object. When compliance is an essential element of the multifingered hand, and the control of the internal forces is not designed to be decoupled from the object motion, it happens that a change in the internal forces causes the object trajectory to deviate from the planned path with consequent performance degradation. This paper studies the structural conditions to design an internal force controller decoupled from object motions. The analysis is constructive and a controller of internal forces is proposed. We will refer to this controller as object motion- decoupled control of internal forces. The force controller has been successfully tested on a realistic model of the DLR Hand II. This controller provides a trajectory interface allowing to vary the internal forces (and to specify object motions) of an underactuated hand, which can be used by higher-level modules, e.g. planning tools.
Author = {Prattichizzo, D. and Malvezzi, M. and Aggravi, M. and Wimboeck, T.},
BookTitle = {{IEEE International Conference on Robotics and Automation (ICRA)}},
Title = {Object motion-decoupled internal force control for a compliant multifingered hand},
Address = {St. Paul, MN, USA},
Year = {2012},
Pages = {1508--1513}
Medical Applications
Hand-Tool-Tissue Interaction Forces in Neurosurgery for Haptic Rendering
2015, Medical & Biomedical Computing & Engineering
Haptics provides sensory stimuli displaying the interaction with virtual or tele-manipulated objects. The haptic feedback can be provided to the user via tactile information and via kinesthetic feedback. Here we focused on measuring the interaction forces during neurosurgical tasks performed on a brain phantom, with the aim of understanding which could be the best haptic feedback in a real tele-operation scenario. We instrumented three neurosurgical tools using Force Sensitive Resistors, for measuring the contact forces exerted by surgeons to tools. A load cell placed under a brain phantom measured the tool-tissue forces. Three neurosurgeons were asked to perform typical actions on the phantom. The measured surgeon-tool contact forces ranges, i.e., 0.01 - 3.49 N for the thumb and 0.01 - 6.6 N for index and middle fingers, fit the range of the cutaneous sensitivity of the human finger pad. The measured tool-tissue interaction forces were from six to eleven times lower with respect to the contact forces, i.e., 0.01 - 0.59 N. Eventually, we believe that convey only the cutaneous component of the haptic feedback would transmit a sensation comparable to that present when both cutaneous and kinesthetic feedback are given. Additionally, this approach does not compromise the stability of the haptic feedback loop.
Author = {Aggravi, M. and De Momi, E and DiMeco, F. and Cardinale, F. and Casaceli, G. and Riva, M. and Ferrigno, G. and Prattichizzo, D.},
Title = {Hand-Tool-Tissue Interaction Forces in Neurosurgery for Haptic Rendering},
Journal = {Medical & Biological Engineering & Computing},
Publisher = {Springer},
url = {},
doi = {10.1007/s11517-015-1439-8},
issn = {0140-0118},
Year = {2015}