Kyle Reed | University of South Florida (original) (raw)

Papers by Kyle Reed

IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004, 2004

Often two people must work together physically on a common task, such as lifting and positioning ... more Often two people must work together physically on a common task, such as lifting and positioning a long board, or, in our model experimental system, turning a two-handled crank. Such tasks involve communication between the people, mediated by the task kinematics and dynamics: each person feels forces and motions produced by the other and derives some meaning from them. Tasks may include a degree of competition: the two people may not have exactly the same goal in mind, and must negotiate a compromise. Understanding human-human communication is important in designing robots for interaction with humans, and for robots that provide powered assistance for human-human tasks (such as physical therapy).

9th International Conference on Rehabilitation Robotics, 2005. ICORR 2005., 2005

In physical and occupational therapy two people interact through force and motion. Other common e... more In physical and occupational therapy two people interact through force and motion. Other common examples of this interaction include lifting and moving a bulky object, teaching manual skills, dancing, and handing off a baton or a drinking glass. These tasks involve kinesthetic interaction, a communication channel distinct from spoken language and gestures. Understanding kinesthetic interaction should be important in designing robots to assist with physical and occupational therapy.

IEEE Transactions on Haptics, 2008

Human partners working on a target acquisition task perform faster than do individuals on the sam... more Human partners working on a target acquisition task perform faster than do individuals on the same task, even though the partners consider each other to be an impediment. We recorded the force profile of each partner during the task, revealing an emergent specialization of roles that could only have been negotiated through a haptic channel. With this understanding of human haptic communication, we attempted a "Haptic Turing Test," replicating human behaviors in a robot partner. Human participants consciously and incorrectly believed their partner was human. However, force profiles did not show specialization of roles in the human partner, nor enhanced dyadic performance, suggesting that haptic interaction holds a greater subconscious subtlety. We further report observations of a nonzero dyadic steady-state force perhaps analogous to cocontraction within the limb of an individual, where it contributes to limb stiffness and disturbance rejection. We present results on disturbance rejection in a dyad, showing lack of an effective dyadic strategy for brief events.

IEEE Transactions on Haptics, 2012

When teaching physical skills, experts or robotic assistants commonly move a novice through a tas... more When teaching physical skills, experts or robotic assistants commonly move a novice through a task. However, this guiding motion is only partially effective at portraying the full experience because the guided person is only performing the task passively and the guidance and task forces can become ambiguously intertwined. The interaction evaluated in this paper separates the task and guidance forces by guiding one hand so the user can actively recreate the motion with their other hand that receives task-related forces. This method is based on the ability of humans to easily move their hands through similar paths, such as drawing circles, compared to the difficulty of simultaneously drawing a square with one hand and a circle with the other. Several experiments were first performed to characterize the reference frames, interaction stiffnesses, and trajectories that humans can recreate. Visual Symmetry and Joint-Space Symmetry proved to be easier than Point Mirror Symmetry and participants' recreated motions typically lagged by approximately 50-100 ms. Based on these results, participants used bimanual guidance to identify the orientation of a hard rod embedded in a soft material. The results show that participants could identify the orientation of the rod equally well when working independently compared to being bimanually guided through a desired motion.

2009 IEEE International Conference on Robotics and Automation, 2009

The asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted i... more The asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted into soft tissue. In this study we present a mechanics-based model that calculates the deflection of the needle embedded in an elastic medium. Microscopic observations for several needle- gel interactions were used to characterize the interactions at the bevel tip and along the needle

Journal of Rehabilitation Robotics, 2013

IEEE International Conference on Robotics and Automation : ICRA : [proceedings] IEEE International Conference on Robotics and Automation, Jan 12, 2009

A flexible needle can be accurately steered by robotically controlling the orientation of the bev... more A flexible needle can be accurately steered by robotically controlling the orientation of the bevel tip as the needle is inserted into tissue. Here, we demonstrate the significant effect of friction between the long, flexible needle shaft and the tissue, which can cause a significant discrepancy between the orientation of the needle tip and the orientation of the base where the needle is controlled. Our experiments show that several common phantom tissues used in needle steering experiments impart substantial frictional forces to the needle shaft, resulting in a lag of over 45° for a 10 cm insertion depth in some phantoms; clinical studies have reported torques large enough to could cause similar errors during needle insertions. Such angle discrepancies will result in poor performance or failure of path planners and image-guided controllers, since the needles used in percutaneous procedures are too small for state-of-the-art imaging to accurately measure the tip angle. To compensate...

Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2009

Needles with asymmetric bevel tips naturally bend when they are inserted into soft tissue. In thi... more Needles with asymmetric bevel tips naturally bend when they are inserted into soft tissue. In this study, we present an analytical model for the loads developed at the bevel tip during needle-tissue interaction. The model calculates the loads based on the geometry of the bevel edge and gel material properties. The modeled transverse force developed at the tip is compared to forces measured experimentally. The analytical model explains the trends observed in the experiments. In addition to macroscopic studies, we also present microscopic observations of needle-tissue interactions. These results contribute to a mechanics-based model of robotic needle steering, extending previous work on kinematic models.

IEEE ... International Conference on Rehabilitation Robotics : [proceedings], 2011

Bimanual rehabilitation devices show promise for use in low cost trainers for home use. To gain a... more Bimanual rehabilitation devices show promise for use in low cost trainers for home use. To gain a better understanding of the symmetry modes and coupling stiffnesses that would be beneficial for home use bimanual trainers, we conducted a haptic tracking task. Participants used one hand to recreate the trajectory applied by a robot to the other hand using three bimanual symmetry modes. The participants recreated visual symmetry and joint space (mirror) symmetry more easily than point mirror symmetry. Joint space symmetry was the easiest mode when the trajectory was an increasing chirp frequency function. The stiffness between the robot and one hand affected the coordination between both hands and stiffnesses of 200-700 N/m enabled better tracking than 50 N/m.

IEEE robotics & automation magazine / IEEE Robotics & Automation Society, Jan 8, 2011

Needle insertion is a critical aspect of many medical treatments, diagnostic methods, and scienti... more Needle insertion is a critical aspect of many medical treatments, diagnostic methods, and scientific studies, and is considered to be one of the simplest and most minimally invasive medical procedures. Robot-assisted needle steering has the potential to improve the effectiveness of existing medical procedures and enable new ones by allowing increased accuracy through more dexterous control of the needle tip path and acquisition of targets not accessible by straight-line trajectories. In this article, we describe a robot-assisted needle steering system that uses three integrated controllers: a motion planner concerned with guiding the needle around obstacles to a target in a desired plane, a planar controller that maintains the needle in the desired plane, and a torsion compensator that controls the needle tip orientation about the axis of the needle shaft. Experimental results from steering an asymmetric-tip needle in artificial tissue demonstrate the effectiveness of the system and...

2006 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2006

Haptic interaction between people and machines might benefit from an understanding of haptic comm... more Haptic interaction between people and machines might benefit from an understanding of haptic communication between one person and another. We recently reported results showing that two people performing a physically shared dyadic task can outperform either person alone, even when the perception of each participant is that the other is a hindrance [1]. Evidently a dyad quickly negotiates a more efficient motion strategy than is available to individuals. This negotiation must take place through a haptic channel of communication, and it is apparently at a level below the awareness of the participants. Here we report results on the motion strategy that emerged. By recording forces and motions we show that the dyads "specialized" temporally such that one member took on early parts of the motion and the other late parts. Tests in which one participant's contribution was surreptitiously replaced by a motor did not elicit a similar cooperative response from the remaining human participant, showing that the language of haptic communication between people must be rather subtle.

2012 4th IEEE RAS & EMBS International Conference on Biomedical Robotics and Biomechatronics (BioRob), 2012

Abstract—This paper presents a theoretical design of a transfemoral prosthesis based on physical ... more Abstract—This paper presents a theoretical design of a transfemoral prosthesis based on physical asymmetries. Breaking the mold of current prostheses, we propose a general prosthetic leg design in which the knee location is shifted off its traditional knee line. The ...

2013 IEEE 13th International Conference on Rehabilitation Robotics (ICORR), 2013

Bimanual rehabilitation allows an individual with hemiparesis to use their sound arm to help reha... more Bimanual rehabilitation allows an individual with hemiparesis to use their sound arm to help rehabilitate their impaired arm and shows promise as a means of low cost home use rehabilitation. However, few studies have attempted to determine the best combination of bimanual symmetry modes and coupling stiffnesses. To examine the effects of stiffness and symmetry type, we have developed a compliant bimanual rehabilitation device (CBRD) that allows the two hands to be coupled in a variety of symmetry modes and coupling stiffnesses so that their efficacy may be tested. Preliminary analysis has shown that the CBRD can couple the motions of two healthy individuals, which we are using to simulate an individual with a hemiparesis, and improves bimanual task performance of a single individual. The results also show that a higher coupling stiffness reduces the coupling error and that some tasks were easier to complete in visual symmetry.

Trends in Augmentation of Human Performance, 2014

World Haptics 2009 - Third Joint EuroHaptics conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems, 2009

Individuals with certain types of central nervous system damage, such as stroke, have an asymmetr... more Individuals with certain types of central nervous system damage, such as stroke, have an asymmetric walking gait. Using a splitbelt treadmill, where each leg walks at a different speed, has been shown to help rehabilitate walking impaired individuals, but there is one distinct drawback; the corrected gait does not transfer well to walking over ground. To increase the gait transference to another environment, we designed and built a passive shoe that admits a motion similar to that felt when walking on a split-belt treadmill. Our gait enhancing mobile shoe (GEMS) alters the wearer's gait by causing one foot to move backward during the stance phase while walking over ground. No external power is required since the shoe mechanically converts the wearers downward and horizontal forces into a backward motion. This shoe would allow a patient to walk over ground while experiencing the same gait altering effects as felt on a split-belt treadmill, which should aid in transferring the corrected gait to walking in natural environments.

Paladyn, 2011

Hemiparesis is a frequent and disabling consequence of stroke and can lead to asymmetric and inef... more Hemiparesis is a frequent and disabling consequence of stroke and can lead to asymmetric and inefficient walking patterns. Training on a split-belt treadmill, which has two separate treads driving each leg at a different speed, can correct such asymmetries post-stroke. However, the effects of split-belt treadmill training only partially transfer to everyday walking over ground and extended training sessions are required to achieve long-lasting effects. Our aim is to develop an alternative device, the Gait Enhancing Mobile Shoe (GEMS), that mimics the actions of the split-belt treadmill, but can be used during overground walking and in one's own home, thus enabling long-term training. The GEMS does not require any external power and is completely passive; all necessary forces are redirected from the natural forces present during walking. Three healthy subjects walked on the shoes for twenty minutes during which one GEMS generated a backward motion and the other GEMS generated a forward motion. Our preliminary experiments suggest that wearing the GEMS did cause subjects to modify coordination between the legs and these changes persisted when subjects returned to normal over-ground walking. The largest effects were observed in measures of temporal coordination (e.g., duration of double-support). These results suggest that the GEMS is capable of altering overground walking coordination in healthy controls and could potentially be used to correct gait asymmetries post-stroke.

2012 IEEE Haptics Symposium (HAPTICS), 2012

Previous studies analyzing the effects of incongruent visual and haptic feedback have found diffe... more Previous studies analyzing the effects of incongruent visual and haptic feedback have found differences in the perceived stiffness of an object depending on what modality was delayed. These studies required only unilateral performance of the individual and did not measure functional task completion. Our study evaluated the effects of incongruent visual and haptic feedback during a bimanual pick and place

2010 IEEE International Conference on Robotics and Automation, 2010

Flexible needles with bevel tips are being developed as useful tools for minimally invasive surge... more Flexible needles with bevel tips are being developed as useful tools for minimally invasive surgery and percutaneous therapy. When such a needle is inserted into soft tissue, it bends due to the asymmetric geometry of the bevel tip. This insertion with bending is not completely repeatable. We characterize the deviations in needle tip pose (position and orientation) by performing repeated needle insertions into artificial tissue. The base of the needle is pushed at a constant speed without rotating, and the covariance of the distribution of the needle tip pose is computed from experimental data. We develop the closed-form equations to describe how the covariance varies with different model parameters. We estimate the model parameters by matching the closed-form covariance and the experimentally obtained covariance. In this work, we use a needle model modified from a previously developed model with two noise parameters. The modified needle model uses three noise parameters to better capture the stochastic behavior of the needle insertion. The modified needle model provides an improvement of the covariance error from 26.1% to 6.55%.

2012 IEEE Haptics Symposium (HAPTICS), 2012

In the sport of combat robotics, there is a strong incentive to produce machines with high power-... more In the sport of combat robotics, there is a strong incentive to produce machines with high power-to-weight ratios. To produce more power, electric motors in these machines are operated well above their rated specifications, leading to a shortened working life and the risk of over-temperature failure. This paper discusses the design of a system to haptically display the instantaneous current

IEEE ... International Conference on Rehabilitation Robotics : [proceedings], 2013

Diminished balance control while walking is a main concern for people with stroke. An appropriate... more Diminished balance control while walking is a main concern for people with stroke. An appropriate training method would help improve their balance during walking. In this study, we examined if a novel robot-assisted balance training (RABT) program could change human gait patterns. Five healthy individuals underwent a RABT program with either stepping or standing movements. An external perturbation using a force field was applied to the lower trunk to alter weight distribution patterns during training. The results showed that people who had a RABT with stepping movements demonstrated a greater change in gait patterns compared to those who had the RABT with standing movements. This suggests that the RABT program with stepping movements can be used as a rehabilitation approach to facilitate an adaptation of a new balance control pattern in human beings.

IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004, 2004

Often two people must work together physically on a common task, such as lifting and positioning ... more Often two people must work together physically on a common task, such as lifting and positioning a long board, or, in our model experimental system, turning a two-handled crank. Such tasks involve communication between the people, mediated by the task kinematics and dynamics: each person feels forces and motions produced by the other and derives some meaning from them. Tasks may include a degree of competition: the two people may not have exactly the same goal in mind, and must negotiate a compromise. Understanding human-human communication is important in designing robots for interaction with humans, and for robots that provide powered assistance for human-human tasks (such as physical therapy).

9th International Conference on Rehabilitation Robotics, 2005. ICORR 2005., 2005

In physical and occupational therapy two people interact through force and motion. Other common e... more In physical and occupational therapy two people interact through force and motion. Other common examples of this interaction include lifting and moving a bulky object, teaching manual skills, dancing, and handing off a baton or a drinking glass. These tasks involve kinesthetic interaction, a communication channel distinct from spoken language and gestures. Understanding kinesthetic interaction should be important in designing robots to assist with physical and occupational therapy.

IEEE Transactions on Haptics, 2008

Human partners working on a target acquisition task perform faster than do individuals on the sam... more Human partners working on a target acquisition task perform faster than do individuals on the same task, even though the partners consider each other to be an impediment. We recorded the force profile of each partner during the task, revealing an emergent specialization of roles that could only have been negotiated through a haptic channel. With this understanding of human haptic communication, we attempted a "Haptic Turing Test," replicating human behaviors in a robot partner. Human participants consciously and incorrectly believed their partner was human. However, force profiles did not show specialization of roles in the human partner, nor enhanced dyadic performance, suggesting that haptic interaction holds a greater subconscious subtlety. We further report observations of a nonzero dyadic steady-state force perhaps analogous to cocontraction within the limb of an individual, where it contributes to limb stiffness and disturbance rejection. We present results on disturbance rejection in a dyad, showing lack of an effective dyadic strategy for brief events.

IEEE Transactions on Haptics, 2012

When teaching physical skills, experts or robotic assistants commonly move a novice through a tas... more When teaching physical skills, experts or robotic assistants commonly move a novice through a task. However, this guiding motion is only partially effective at portraying the full experience because the guided person is only performing the task passively and the guidance and task forces can become ambiguously intertwined. The interaction evaluated in this paper separates the task and guidance forces by guiding one hand so the user can actively recreate the motion with their other hand that receives task-related forces. This method is based on the ability of humans to easily move their hands through similar paths, such as drawing circles, compared to the difficulty of simultaneously drawing a square with one hand and a circle with the other. Several experiments were first performed to characterize the reference frames, interaction stiffnesses, and trajectories that humans can recreate. Visual Symmetry and Joint-Space Symmetry proved to be easier than Point Mirror Symmetry and participants' recreated motions typically lagged by approximately 50-100 ms. Based on these results, participants used bimanual guidance to identify the orientation of a hard rod embedded in a soft material. The results show that participants could identify the orientation of the rod equally well when working independently compared to being bimanually guided through a desired motion.

2009 IEEE International Conference on Robotics and Automation, 2009

The asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted i... more The asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted into soft tissue. In this study we present a mechanics-based model that calculates the deflection of the needle embedded in an elastic medium. Microscopic observations for several needle- gel interactions were used to characterize the interactions at the bevel tip and along the needle

Journal of Rehabilitation Robotics, 2013

IEEE International Conference on Robotics and Automation : ICRA : [proceedings] IEEE International Conference on Robotics and Automation, Jan 12, 2009

A flexible needle can be accurately steered by robotically controlling the orientation of the bev... more A flexible needle can be accurately steered by robotically controlling the orientation of the bevel tip as the needle is inserted into tissue. Here, we demonstrate the significant effect of friction between the long, flexible needle shaft and the tissue, which can cause a significant discrepancy between the orientation of the needle tip and the orientation of the base where the needle is controlled. Our experiments show that several common phantom tissues used in needle steering experiments impart substantial frictional forces to the needle shaft, resulting in a lag of over 45° for a 10 cm insertion depth in some phantoms; clinical studies have reported torques large enough to could cause similar errors during needle insertions. Such angle discrepancies will result in poor performance or failure of path planners and image-guided controllers, since the needles used in percutaneous procedures are too small for state-of-the-art imaging to accurately measure the tip angle. To compensate...

Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2009

Needles with asymmetric bevel tips naturally bend when they are inserted into soft tissue. In thi... more Needles with asymmetric bevel tips naturally bend when they are inserted into soft tissue. In this study, we present an analytical model for the loads developed at the bevel tip during needle-tissue interaction. The model calculates the loads based on the geometry of the bevel edge and gel material properties. The modeled transverse force developed at the tip is compared to forces measured experimentally. The analytical model explains the trends observed in the experiments. In addition to macroscopic studies, we also present microscopic observations of needle-tissue interactions. These results contribute to a mechanics-based model of robotic needle steering, extending previous work on kinematic models.

IEEE ... International Conference on Rehabilitation Robotics : [proceedings], 2011

Bimanual rehabilitation devices show promise for use in low cost trainers for home use. To gain a... more Bimanual rehabilitation devices show promise for use in low cost trainers for home use. To gain a better understanding of the symmetry modes and coupling stiffnesses that would be beneficial for home use bimanual trainers, we conducted a haptic tracking task. Participants used one hand to recreate the trajectory applied by a robot to the other hand using three bimanual symmetry modes. The participants recreated visual symmetry and joint space (mirror) symmetry more easily than point mirror symmetry. Joint space symmetry was the easiest mode when the trajectory was an increasing chirp frequency function. The stiffness between the robot and one hand affected the coordination between both hands and stiffnesses of 200-700 N/m enabled better tracking than 50 N/m.

IEEE robotics & automation magazine / IEEE Robotics & Automation Society, Jan 8, 2011

Needle insertion is a critical aspect of many medical treatments, diagnostic methods, and scienti... more Needle insertion is a critical aspect of many medical treatments, diagnostic methods, and scientific studies, and is considered to be one of the simplest and most minimally invasive medical procedures. Robot-assisted needle steering has the potential to improve the effectiveness of existing medical procedures and enable new ones by allowing increased accuracy through more dexterous control of the needle tip path and acquisition of targets not accessible by straight-line trajectories. In this article, we describe a robot-assisted needle steering system that uses three integrated controllers: a motion planner concerned with guiding the needle around obstacles to a target in a desired plane, a planar controller that maintains the needle in the desired plane, and a torsion compensator that controls the needle tip orientation about the axis of the needle shaft. Experimental results from steering an asymmetric-tip needle in artificial tissue demonstrate the effectiveness of the system and...

2006 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2006

Haptic interaction between people and machines might benefit from an understanding of haptic comm... more Haptic interaction between people and machines might benefit from an understanding of haptic communication between one person and another. We recently reported results showing that two people performing a physically shared dyadic task can outperform either person alone, even when the perception of each participant is that the other is a hindrance [1]. Evidently a dyad quickly negotiates a more efficient motion strategy than is available to individuals. This negotiation must take place through a haptic channel of communication, and it is apparently at a level below the awareness of the participants. Here we report results on the motion strategy that emerged. By recording forces and motions we show that the dyads "specialized" temporally such that one member took on early parts of the motion and the other late parts. Tests in which one participant's contribution was surreptitiously replaced by a motor did not elicit a similar cooperative response from the remaining human participant, showing that the language of haptic communication between people must be rather subtle.

2012 4th IEEE RAS & EMBS International Conference on Biomedical Robotics and Biomechatronics (BioRob), 2012

Abstract—This paper presents a theoretical design of a transfemoral prosthesis based on physical ... more Abstract—This paper presents a theoretical design of a transfemoral prosthesis based on physical asymmetries. Breaking the mold of current prostheses, we propose a general prosthetic leg design in which the knee location is shifted off its traditional knee line. The ...

2013 IEEE 13th International Conference on Rehabilitation Robotics (ICORR), 2013

Bimanual rehabilitation allows an individual with hemiparesis to use their sound arm to help reha... more Bimanual rehabilitation allows an individual with hemiparesis to use their sound arm to help rehabilitate their impaired arm and shows promise as a means of low cost home use rehabilitation. However, few studies have attempted to determine the best combination of bimanual symmetry modes and coupling stiffnesses. To examine the effects of stiffness and symmetry type, we have developed a compliant bimanual rehabilitation device (CBRD) that allows the two hands to be coupled in a variety of symmetry modes and coupling stiffnesses so that their efficacy may be tested. Preliminary analysis has shown that the CBRD can couple the motions of two healthy individuals, which we are using to simulate an individual with a hemiparesis, and improves bimanual task performance of a single individual. The results also show that a higher coupling stiffness reduces the coupling error and that some tasks were easier to complete in visual symmetry.

Trends in Augmentation of Human Performance, 2014

World Haptics 2009 - Third Joint EuroHaptics conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems, 2009

Individuals with certain types of central nervous system damage, such as stroke, have an asymmetr... more Individuals with certain types of central nervous system damage, such as stroke, have an asymmetric walking gait. Using a splitbelt treadmill, where each leg walks at a different speed, has been shown to help rehabilitate walking impaired individuals, but there is one distinct drawback; the corrected gait does not transfer well to walking over ground. To increase the gait transference to another environment, we designed and built a passive shoe that admits a motion similar to that felt when walking on a split-belt treadmill. Our gait enhancing mobile shoe (GEMS) alters the wearer's gait by causing one foot to move backward during the stance phase while walking over ground. No external power is required since the shoe mechanically converts the wearers downward and horizontal forces into a backward motion. This shoe would allow a patient to walk over ground while experiencing the same gait altering effects as felt on a split-belt treadmill, which should aid in transferring the corrected gait to walking in natural environments.

Paladyn, 2011

Hemiparesis is a frequent and disabling consequence of stroke and can lead to asymmetric and inef... more Hemiparesis is a frequent and disabling consequence of stroke and can lead to asymmetric and inefficient walking patterns. Training on a split-belt treadmill, which has two separate treads driving each leg at a different speed, can correct such asymmetries post-stroke. However, the effects of split-belt treadmill training only partially transfer to everyday walking over ground and extended training sessions are required to achieve long-lasting effects. Our aim is to develop an alternative device, the Gait Enhancing Mobile Shoe (GEMS), that mimics the actions of the split-belt treadmill, but can be used during overground walking and in one's own home, thus enabling long-term training. The GEMS does not require any external power and is completely passive; all necessary forces are redirected from the natural forces present during walking. Three healthy subjects walked on the shoes for twenty minutes during which one GEMS generated a backward motion and the other GEMS generated a forward motion. Our preliminary experiments suggest that wearing the GEMS did cause subjects to modify coordination between the legs and these changes persisted when subjects returned to normal over-ground walking. The largest effects were observed in measures of temporal coordination (e.g., duration of double-support). These results suggest that the GEMS is capable of altering overground walking coordination in healthy controls and could potentially be used to correct gait asymmetries post-stroke.

2012 IEEE Haptics Symposium (HAPTICS), 2012

Previous studies analyzing the effects of incongruent visual and haptic feedback have found diffe... more Previous studies analyzing the effects of incongruent visual and haptic feedback have found differences in the perceived stiffness of an object depending on what modality was delayed. These studies required only unilateral performance of the individual and did not measure functional task completion. Our study evaluated the effects of incongruent visual and haptic feedback during a bimanual pick and place

2010 IEEE International Conference on Robotics and Automation, 2010

Flexible needles with bevel tips are being developed as useful tools for minimally invasive surge... more Flexible needles with bevel tips are being developed as useful tools for minimally invasive surgery and percutaneous therapy. When such a needle is inserted into soft tissue, it bends due to the asymmetric geometry of the bevel tip. This insertion with bending is not completely repeatable. We characterize the deviations in needle tip pose (position and orientation) by performing repeated needle insertions into artificial tissue. The base of the needle is pushed at a constant speed without rotating, and the covariance of the distribution of the needle tip pose is computed from experimental data. We develop the closed-form equations to describe how the covariance varies with different model parameters. We estimate the model parameters by matching the closed-form covariance and the experimentally obtained covariance. In this work, we use a needle model modified from a previously developed model with two noise parameters. The modified needle model uses three noise parameters to better capture the stochastic behavior of the needle insertion. The modified needle model provides an improvement of the covariance error from 26.1% to 6.55%.

2012 IEEE Haptics Symposium (HAPTICS), 2012

In the sport of combat robotics, there is a strong incentive to produce machines with high power-... more In the sport of combat robotics, there is a strong incentive to produce machines with high power-to-weight ratios. To produce more power, electric motors in these machines are operated well above their rated specifications, leading to a shortened working life and the risk of over-temperature failure. This paper discusses the design of a system to haptically display the instantaneous current

IEEE ... International Conference on Rehabilitation Robotics : [proceedings], 2013

Diminished balance control while walking is a main concern for people with stroke. An appropriate... more Diminished balance control while walking is a main concern for people with stroke. An appropriate training method would help improve their balance during walking. In this study, we examined if a novel robot-assisted balance training (RABT) program could change human gait patterns. Five healthy individuals underwent a RABT program with either stepping or standing movements. An external perturbation using a force field was applied to the lower trunk to alter weight distribution patterns during training. The results showed that people who had a RABT with stepping movements demonstrated a greater change in gait patterns compared to those who had the RABT with standing movements. This suggests that the RABT program with stepping movements can be used as a rehabilitation approach to facilitate an adaptation of a new balance control pattern in human beings.