Patrick Riley - Academia.edu (original) (raw)

Papers by Patrick Riley

Annals of advances in automotive medicine / Annual Scientific Conference ... Association for the Advancement of Automotive Medicine. Association for the Advancement of Automotive Medicine. Scientific Conference, 2011

A growing body of literature points out the relevance of the thoracic spine dynamics in understan... more A growing body of literature points out the relevance of the thoracic spine dynamics in understanding the thoraxrestraint interaction as well as in determining the kinematics of the head and cervical spine. This study characterizes the dynamic response in bending of eight human spinal specimens (4 pediatric: ages 7 and 15 years, 4 adult: ages 48 and 52 years) from two sections along the thoracic spine (T2-T4 and T7-T9). Each specimen consisted of three vertebral bodies connected by the corresponding intervertebral discs. All ligaments were preserved in the preparation with the exception of the inter-transverse ligament. Specimens were exposed to a series of five dynamic bending ramp-and-hold tests with varying amplitudes at a nominal rate of 2 rad/s. After this battery of tests, failure experiments were conducted. The 7-year-old specimen showed the lowest tolerance to a moment (T2-T4: 12.1 Nm; T7-T9: 11.6 Nm) with no significant reduction of the relative rotation between the vertebrae. The 15-year-old failure tolerance was comparable to that of the adult specimens. Failure of the adult specimens occurred within a wide range at the T2-T4 thoracic section (23.3 Nm-53.0 Nm) while it was circumscribed to the interval 48.3 Nm-52.5 Nm for the T7-T9 section. The series of dynamic ramp-and-hold were used to assess two different scaling methods (mass scaling and SAE scaling). Neither method was able to capture the stiffness, peak moment and relaxation characteristics exhibited by the pediatric specimens.

Physical Therapy

This article describes the sit-to-stand movement in nine healthy elderly adults, ages 61 to 74 ye... more This article describes the sit-to-stand movement in nine healthy elderly adults, ages 61 to 74 years, and comparespeak joint angles, torques, and velocities of 11 body segments with data collected from nine young women, ages 25 to 3 6 years. The subjects in this study rose from a chair under a controlled protocol. An optoelectronic; system, two force plates, and two computers were used for data collection and processing. The data are described in relationship to three phases of the task previously described for the young subjects' data. Percentages of d@erence were cak:ulated for the torques and the velocities. Independent t tests were conducted on maximum angles achieved and total joint excursions. Com'stency between groups was demonstrated in the duration of each phase, as well as the baiy kin'ematics and kinetics occurring within each phase. There was little dzfference in rnuximum torques or velocities. Maximum angles of head-to-trunk extension, head-to-groundfexion, head-to-trunk excursion, and trunk-to-pelvisflexion were s2gttiJicantly different between groups. The dtfferences in head position demonstrated between these two groups may have clinical implications for loss of balance during this task in older patients. [Ikeda ER, Schenkman ML, Riley PO, Hodge EN. Influence of age on dynamics of nkingfrom a chair. Phys Ther. 1991; 71:473481.] The ability to rise unassisted from a ence. We believe that, without a chair is a prerequisite to many activ-quantitative description of what conities of daily living. In teaching pa-stitutes normal rising, there can be tients this activity, therapists have no demonstration of the efficacy of previously relied on qualitative con-using clinical models. ceptual models and clinical experi-Because of the complexity of testing and analyzing the task of rising, several studies have focused on specific aspects of the sit-to-stand movement. Several investigators1-4 examined only the kinematics of rising, and others5-l4 studied only the lower-extremity dynamics. Consequently, there is a need for greater knowledge concerning integrated upper-body and lower-extremity kinematics and kinetics. Describing total-body kinematics of geriatric subjects in rising from a chair is necessary to further delineate differences between young and elderly subjects and provides data for future comparisons with kinematic data of elderly persons with pathology and dysfunction.

Physical Therapy

Rising to a standing position from a sitting position is one of the most important activities of ... more Rising to a standing position from a sitting position is one of the most important activities of daily life. We present a total-body analysis of rising from a chair as performed by nine healthy individuals under controlled conditions. We describe four phases of this activity. Phase I is a flexion-momentum phase used to generate the initial momentum for rising. Phase II begins as the individual leaves the chair seat and ends at maximal ankle dorsiflexion. Forward momentum of the upper body is transferred to forward and upward momentum of the total body. Phase III is an extension phase during which the body rises to its full upright position. Phase IV is a stabilization phase. Kinetics and kinematics of the phases are analyzed. The phases are differentiated in terms of momentum and stability characteristics. Clinical implications of the mechanics of rising are discussed.

Pigment Cell Research

It has been shown previously that the initial product of mushroom tyrosinase-catalysed oxidation ... more It has been shown previously that the initial product of mushroom tyrosinase-catalysed oxidation of the monophenol &hydroxyanisole (4HA) is 4-methoxy ortho benzoquinone (4-MOB). This study presents evidence that 4-MOB is primarily responsible for the cytotoxicity of 4HA oxidation products in vitro. Equivalent toxicity in a model system was produced by products of tyrosinase catalysed oxidation of 4HA and by synthetic 4-MOB. Cytotoxicity was estimated both by a blebbing assay and by plating efficiency of exposed cells. HPLC analysis of the reaction mixture revealed a positive correlation between cytotoxicity and 4-MOB concentration.

Microcirculation, endothelium, and lymphatics

The regional distribution of mast cells and the microvascular pattern in the stomach of Wistar ra... more The regional distribution of mast cells and the microvascular pattern in the stomach of Wistar rats fed on an ulcerogenic diet were compared with those of control animals. Mounts of the distended stomach were made and stained for blood vessels and mast cells in the subserosal layer. Measurements made under dark ground illumination in 12 operationally defined regions of the serosa demonstrated that the stomach wall in the region around the oesophagus is more richly vascularised and possesses a greater number of mast cells (60 cells per mm2) than other regions. Changes in the mast cells and microvasculature were observed in rats fed an ulcerogenic diet, notably in the zone around the oesophagus, where more than 30% mast cells were degranulated and the mean vascular diameter increased by 26%. The severity of the vascular changes correlated with the location of the ulcers of which 50% were in the zone surrounding the oesophagus.

Stapp car crash journal, 2014

The objective of the current study was to characterize the whole-body kinematic response of restr... more The objective of the current study was to characterize the whole-body kinematic response of restrained PMHS in controlled laboratory rollover tests. A dynamic rollover test system (DRoTS) and a parametric vehicle buck were used to conduct 36 rollover tests on four adult male PMHS with varied test conditions to study occupant kinematics during the rollover event. The DRoTS was used to drop/catch and rotate the test buck, which replicated the occupant compartment of a typical mid-sized SUV, around its center of gravity without roof-to-ground contact. The studied test conditions included a quasi-static inversion (4 tests), an inverted drop and catch that produced a 3 g vertical deceleration (4 tests), a pure dynamic roll at 360 degrees/second (11 tests), and a roll with a superimposed drop and catch produced vertical deceleration (17 tests). Each PMHS was restrained with a three-point belt and was tested in both leading-side and trailing-side front-row seating positions. Whole-body kin...

Stapp car crash journal, 2014

Rollover crashes are a serious public health problem in United States, with one third of traffic ... more Rollover crashes are a serious public health problem in United States, with one third of traffic fatalities occurring in crashes where rollover occurred. While it has been shown that occupant kinematics affect the injury risk in rollover crashes, no anthropomorphic test device (ATD) has yet demonstrated kinematic biofidelity in rollover crashes. Therefore, the primary goal of this study was to assess the kinematic response biofidelity of six ATDs (Hybrid III, Hybrid III Pedestrian, Hybrid III with Pedestrian Pelvis, WorldSID, Polar II and THOR) by comparing them to post mortem human surrogate (PMHS) kinematic response targets published concurrently; and the secondary goal was to evaluate and compare the kinematic response differences among these ATDs. Trajectories (head, T1, T4, T10, L1 and sacrum), spinal segment (head-to-T1, T1-to-T4, T4-T10, T10-L1, and L1-to-sacrum) rotations relative to the rollover buck, and spinal segment extension/compression were calculated from the collect...

Journal of Biological Chemistry

We have observed the formation of free radicals during the oxidation of the melanocytotoxic agent... more We have observed the formation of free radicals during the oxidation of the melanocytotoxic agent 4-hydroxyanisole with the enzyme tyrosinase as a catalyst. The first free radical to form is identified as the 4-methoxy-1,2-benzosemiquinone radical anion. The peak concentration of this radical increases with tyrosinase concentration; a minimum concentration of 50 micrograms/ml of tyrosinase was needed to observe this radical. The peak concentration of this radical is independent of 4-hydroxyanisole concentration. This radical is produced by reverse dismutation of the primary product, 4-methoxy-1,2-benzoquinone and 4-methoxycatechol produced indirectly.

We investigated the head stabilization reference frame and whether normal stabilization differs f... more We investigated the head stabilization reference frame and whether normal stabilization differs from that of subjects with bilateral vestibular hypofunction (BVH). Head and trunk translational and angular motion, velocity and acceleration were obtained in global (gravity) coordinates, as well as from head with respect to trunk. Ten subjects with BVH and ten age and sex matched healthy control humans, 28 to 80 y.o. were studied during preferred speed rising from a chair with visual guidance (eyes open). BVH patients had absent caloric responses and VOR gains of less than 0.1 at 0.5 Hz during sinusoidal rotation. Head-trunk kinematics were measured by a SELSPOT II active marker system at 150 Hz sampling frequency. Time derivatives of the motion were numerically derived by a Kalman estimator. The experimental data show that the head is stabilized in attitude with respect to the gravity frame (floating platform guidance) in both groups. The peak angular rates for normal subjects are app...

[1990] Proceedings of the Twelfth Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1990

Ten subjects were studied performing a constrained chair rise task Each subject performed at leas... more Ten subjects were studied performing a constrained chair rise task Each subject performed at least two chair rise trials at hidher own chosen speed as well as at least two trials in which the maneuver was paced. The effect of pacing on the whole body center of mass (COM) linear kinetic energy curves was accessed. The reproducibility of the curves was measured using the coefficient of multiple determination Pacing was found to make the curves of the 5 young and 5 elder subjects more similar. However, the curves for the paced trials differed from those of the free speed trials. Thus, the decision to constrain the task must be made with due consideration of the purpose of the testing. Constraining pace may be necessary to permit intergroup comparisons. but may preclude observation of normal performance

Stapp car crash journal

In far-side impacts, head contact with interior components is a key injury mechanism. Restraint c... more In far-side impacts, head contact with interior components is a key injury mechanism. Restraint characteristics have a pronounced influence on head motion and injury risk. This study performed a parametric examination of restraint, positioning, and collision factors affecting shoulder belt retention and occupant kinematics in far-side lateral and oblique sled tests with post mortem human subjects (PMHS). Seven PMHS were subjected to repeated tests varying the D-ring position, arm position, pelvis restraint, pre-tensioning, and impact severity. Each PMHS was subjected to four low-severity tests (6.6 g sled acceleration pulse) in which the restraint or position parameters were varied and then a single higher-severity test (14 g) with a chosen restraint configuration (total of 36 tests). Three PMHS were tested in a purely lateral (90° from frontal) impact direction; 4 were tested in an oblique impact (60° from frontal). All subjects were restrained by a 3-point seatbelt. Occupant motio...

Stapp car crash journal

The objective of the current study was to provide a comprehensive characterization of human biome... more The objective of the current study was to provide a comprehensive characterization of human biomechanical response to whole-body, lateral impact. Three approximately 50th-percentile adult male PMHS were subjected to right-side pure lateral impacts at 4.3 ± 0.1 m/s using a rigid wall mounted to a rail-mounted sled. Each subject was positioned on a rigid seat and held stationary by a system of tethers until immediately prior to being impacted by the moving wall with 100 mm pelvic offset. Displacement data were obtained using an optoelectronic stereophotogrammetric system that was used to track the 3D motions of the impacting wall sled; seat sled, and reflective targets secured to the head, spine, extremities, ribcage, and shoulder complex of each subject. Kinematic data were also recorded using 3-axis accelerometer cubes secured to the head, pelvis, and spine at the levels of T1, T6, T11, and L3. Chest deformation in the transverse plane was recorded using a single chestband. Followin...

Proceedings of the 2004 IEEE International Conference on Control Applications, 2004., 2004

Abstract This study is concerned with the control system design using Labview real time module an... more Abstract This study is concerned with the control system design using Labview real time module and Matlab/Simulink combined system for an application to the partial body weight support (PBWS) system for human gait training actuated by a linear motor moving in ...

Understanding propulsion and adaptation to speed requirements is important in determining appropr... more Understanding propulsion and adaptation to speed requirements is important in determining appropriate therapies for gait disorders. We hypothesize that adaptations for changing speed requirements occur primarily at the hip. The slow, normal and fast gait of 24 healthy young subjects was analyzed. The linear power was analyzed at the hip joint. The anterior}posterior and vertical induced accelerations of the hip

Annals of advances in automotive medicine / Annual Scientific Conference ... Association for the Advancement of Automotive Medicine. Association for the Advancement of Automotive Medicine. Scientific Conference, 2011

A growing body of literature points out the relevance of the thoracic spine dynamics in understan... more A growing body of literature points out the relevance of the thoracic spine dynamics in understanding the thoraxrestraint interaction as well as in determining the kinematics of the head and cervical spine. This study characterizes the dynamic response in bending of eight human spinal specimens (4 pediatric: ages 7 and 15 years, 4 adult: ages 48 and 52 years) from two sections along the thoracic spine (T2-T4 and T7-T9). Each specimen consisted of three vertebral bodies connected by the corresponding intervertebral discs. All ligaments were preserved in the preparation with the exception of the inter-transverse ligament. Specimens were exposed to a series of five dynamic bending ramp-and-hold tests with varying amplitudes at a nominal rate of 2 rad/s. After this battery of tests, failure experiments were conducted. The 7-year-old specimen showed the lowest tolerance to a moment (T2-T4: 12.1 Nm; T7-T9: 11.6 Nm) with no significant reduction of the relative rotation between the vertebrae. The 15-year-old failure tolerance was comparable to that of the adult specimens. Failure of the adult specimens occurred within a wide range at the T2-T4 thoracic section (23.3 Nm-53.0 Nm) while it was circumscribed to the interval 48.3 Nm-52.5 Nm for the T7-T9 section. The series of dynamic ramp-and-hold were used to assess two different scaling methods (mass scaling and SAE scaling). Neither method was able to capture the stiffness, peak moment and relaxation characteristics exhibited by the pediatric specimens.

Physical Therapy

This article describes the sit-to-stand movement in nine healthy elderly adults, ages 61 to 74 ye... more This article describes the sit-to-stand movement in nine healthy elderly adults, ages 61 to 74 years, and comparespeak joint angles, torques, and velocities of 11 body segments with data collected from nine young women, ages 25 to 3 6 years. The subjects in this study rose from a chair under a controlled protocol. An optoelectronic; system, two force plates, and two computers were used for data collection and processing. The data are described in relationship to three phases of the task previously described for the young subjects' data. Percentages of d@erence were cak:ulated for the torques and the velocities. Independent t tests were conducted on maximum angles achieved and total joint excursions. Com'stency between groups was demonstrated in the duration of each phase, as well as the baiy kin'ematics and kinetics occurring within each phase. There was little dzfference in rnuximum torques or velocities. Maximum angles of head-to-trunk extension, head-to-groundfexion, head-to-trunk excursion, and trunk-to-pelvisflexion were s2gttiJicantly different between groups. The dtfferences in head position demonstrated between these two groups may have clinical implications for loss of balance during this task in older patients. [Ikeda ER, Schenkman ML, Riley PO, Hodge EN. Influence of age on dynamics of nkingfrom a chair. Phys Ther. 1991; 71:473481.] The ability to rise unassisted from a ence. We believe that, without a chair is a prerequisite to many activ-quantitative description of what conities of daily living. In teaching pa-stitutes normal rising, there can be tients this activity, therapists have no demonstration of the efficacy of previously relied on qualitative con-using clinical models. ceptual models and clinical experi-Because of the complexity of testing and analyzing the task of rising, several studies have focused on specific aspects of the sit-to-stand movement. Several investigators1-4 examined only the kinematics of rising, and others5-l4 studied only the lower-extremity dynamics. Consequently, there is a need for greater knowledge concerning integrated upper-body and lower-extremity kinematics and kinetics. Describing total-body kinematics of geriatric subjects in rising from a chair is necessary to further delineate differences between young and elderly subjects and provides data for future comparisons with kinematic data of elderly persons with pathology and dysfunction.

Physical Therapy

Rising to a standing position from a sitting position is one of the most important activities of ... more Rising to a standing position from a sitting position is one of the most important activities of daily life. We present a total-body analysis of rising from a chair as performed by nine healthy individuals under controlled conditions. We describe four phases of this activity. Phase I is a flexion-momentum phase used to generate the initial momentum for rising. Phase II begins as the individual leaves the chair seat and ends at maximal ankle dorsiflexion. Forward momentum of the upper body is transferred to forward and upward momentum of the total body. Phase III is an extension phase during which the body rises to its full upright position. Phase IV is a stabilization phase. Kinetics and kinematics of the phases are analyzed. The phases are differentiated in terms of momentum and stability characteristics. Clinical implications of the mechanics of rising are discussed.

Pigment Cell Research

It has been shown previously that the initial product of mushroom tyrosinase-catalysed oxidation ... more It has been shown previously that the initial product of mushroom tyrosinase-catalysed oxidation of the monophenol &hydroxyanisole (4HA) is 4-methoxy ortho benzoquinone (4-MOB). This study presents evidence that 4-MOB is primarily responsible for the cytotoxicity of 4HA oxidation products in vitro. Equivalent toxicity in a model system was produced by products of tyrosinase catalysed oxidation of 4HA and by synthetic 4-MOB. Cytotoxicity was estimated both by a blebbing assay and by plating efficiency of exposed cells. HPLC analysis of the reaction mixture revealed a positive correlation between cytotoxicity and 4-MOB concentration.

Microcirculation, endothelium, and lymphatics

The regional distribution of mast cells and the microvascular pattern in the stomach of Wistar ra... more The regional distribution of mast cells and the microvascular pattern in the stomach of Wistar rats fed on an ulcerogenic diet were compared with those of control animals. Mounts of the distended stomach were made and stained for blood vessels and mast cells in the subserosal layer. Measurements made under dark ground illumination in 12 operationally defined regions of the serosa demonstrated that the stomach wall in the region around the oesophagus is more richly vascularised and possesses a greater number of mast cells (60 cells per mm2) than other regions. Changes in the mast cells and microvasculature were observed in rats fed an ulcerogenic diet, notably in the zone around the oesophagus, where more than 30% mast cells were degranulated and the mean vascular diameter increased by 26%. The severity of the vascular changes correlated with the location of the ulcers of which 50% were in the zone surrounding the oesophagus.

Stapp car crash journal, 2014

The objective of the current study was to characterize the whole-body kinematic response of restr... more The objective of the current study was to characterize the whole-body kinematic response of restrained PMHS in controlled laboratory rollover tests. A dynamic rollover test system (DRoTS) and a parametric vehicle buck were used to conduct 36 rollover tests on four adult male PMHS with varied test conditions to study occupant kinematics during the rollover event. The DRoTS was used to drop/catch and rotate the test buck, which replicated the occupant compartment of a typical mid-sized SUV, around its center of gravity without roof-to-ground contact. The studied test conditions included a quasi-static inversion (4 tests), an inverted drop and catch that produced a 3 g vertical deceleration (4 tests), a pure dynamic roll at 360 degrees/second (11 tests), and a roll with a superimposed drop and catch produced vertical deceleration (17 tests). Each PMHS was restrained with a three-point belt and was tested in both leading-side and trailing-side front-row seating positions. Whole-body kin...

Stapp car crash journal, 2014

Rollover crashes are a serious public health problem in United States, with one third of traffic ... more Rollover crashes are a serious public health problem in United States, with one third of traffic fatalities occurring in crashes where rollover occurred. While it has been shown that occupant kinematics affect the injury risk in rollover crashes, no anthropomorphic test device (ATD) has yet demonstrated kinematic biofidelity in rollover crashes. Therefore, the primary goal of this study was to assess the kinematic response biofidelity of six ATDs (Hybrid III, Hybrid III Pedestrian, Hybrid III with Pedestrian Pelvis, WorldSID, Polar II and THOR) by comparing them to post mortem human surrogate (PMHS) kinematic response targets published concurrently; and the secondary goal was to evaluate and compare the kinematic response differences among these ATDs. Trajectories (head, T1, T4, T10, L1 and sacrum), spinal segment (head-to-T1, T1-to-T4, T4-T10, T10-L1, and L1-to-sacrum) rotations relative to the rollover buck, and spinal segment extension/compression were calculated from the collect...

Journal of Biological Chemistry

We have observed the formation of free radicals during the oxidation of the melanocytotoxic agent... more We have observed the formation of free radicals during the oxidation of the melanocytotoxic agent 4-hydroxyanisole with the enzyme tyrosinase as a catalyst. The first free radical to form is identified as the 4-methoxy-1,2-benzosemiquinone radical anion. The peak concentration of this radical increases with tyrosinase concentration; a minimum concentration of 50 micrograms/ml of tyrosinase was needed to observe this radical. The peak concentration of this radical is independent of 4-hydroxyanisole concentration. This radical is produced by reverse dismutation of the primary product, 4-methoxy-1,2-benzoquinone and 4-methoxycatechol produced indirectly.

We investigated the head stabilization reference frame and whether normal stabilization differs f... more We investigated the head stabilization reference frame and whether normal stabilization differs from that of subjects with bilateral vestibular hypofunction (BVH). Head and trunk translational and angular motion, velocity and acceleration were obtained in global (gravity) coordinates, as well as from head with respect to trunk. Ten subjects with BVH and ten age and sex matched healthy control humans, 28 to 80 y.o. were studied during preferred speed rising from a chair with visual guidance (eyes open). BVH patients had absent caloric responses and VOR gains of less than 0.1 at 0.5 Hz during sinusoidal rotation. Head-trunk kinematics were measured by a SELSPOT II active marker system at 150 Hz sampling frequency. Time derivatives of the motion were numerically derived by a Kalman estimator. The experimental data show that the head is stabilized in attitude with respect to the gravity frame (floating platform guidance) in both groups. The peak angular rates for normal subjects are app...

[1990] Proceedings of the Twelfth Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1990

Ten subjects were studied performing a constrained chair rise task Each subject performed at leas... more Ten subjects were studied performing a constrained chair rise task Each subject performed at least two chair rise trials at hidher own chosen speed as well as at least two trials in which the maneuver was paced. The effect of pacing on the whole body center of mass (COM) linear kinetic energy curves was accessed. The reproducibility of the curves was measured using the coefficient of multiple determination Pacing was found to make the curves of the 5 young and 5 elder subjects more similar. However, the curves for the paced trials differed from those of the free speed trials. Thus, the decision to constrain the task must be made with due consideration of the purpose of the testing. Constraining pace may be necessary to permit intergroup comparisons. but may preclude observation of normal performance

Stapp car crash journal

In far-side impacts, head contact with interior components is a key injury mechanism. Restraint c... more In far-side impacts, head contact with interior components is a key injury mechanism. Restraint characteristics have a pronounced influence on head motion and injury risk. This study performed a parametric examination of restraint, positioning, and collision factors affecting shoulder belt retention and occupant kinematics in far-side lateral and oblique sled tests with post mortem human subjects (PMHS). Seven PMHS were subjected to repeated tests varying the D-ring position, arm position, pelvis restraint, pre-tensioning, and impact severity. Each PMHS was subjected to four low-severity tests (6.6 g sled acceleration pulse) in which the restraint or position parameters were varied and then a single higher-severity test (14 g) with a chosen restraint configuration (total of 36 tests). Three PMHS were tested in a purely lateral (90° from frontal) impact direction; 4 were tested in an oblique impact (60° from frontal). All subjects were restrained by a 3-point seatbelt. Occupant motio...

Stapp car crash journal

The objective of the current study was to provide a comprehensive characterization of human biome... more The objective of the current study was to provide a comprehensive characterization of human biomechanical response to whole-body, lateral impact. Three approximately 50th-percentile adult male PMHS were subjected to right-side pure lateral impacts at 4.3 ± 0.1 m/s using a rigid wall mounted to a rail-mounted sled. Each subject was positioned on a rigid seat and held stationary by a system of tethers until immediately prior to being impacted by the moving wall with 100 mm pelvic offset. Displacement data were obtained using an optoelectronic stereophotogrammetric system that was used to track the 3D motions of the impacting wall sled; seat sled, and reflective targets secured to the head, spine, extremities, ribcage, and shoulder complex of each subject. Kinematic data were also recorded using 3-axis accelerometer cubes secured to the head, pelvis, and spine at the levels of T1, T6, T11, and L3. Chest deformation in the transverse plane was recorded using a single chestband. Followin...

Proceedings of the 2004 IEEE International Conference on Control Applications, 2004., 2004

Abstract This study is concerned with the control system design using Labview real time module an... more Abstract This study is concerned with the control system design using Labview real time module and Matlab/Simulink combined system for an application to the partial body weight support (PBWS) system for human gait training actuated by a linear motor moving in ...

Understanding propulsion and adaptation to speed requirements is important in determining appropr... more Understanding propulsion and adaptation to speed requirements is important in determining appropriate therapies for gait disorders. We hypothesize that adaptations for changing speed requirements occur primarily at the hip. The slow, normal and fast gait of 24 healthy young subjects was analyzed. The linear power was analyzed at the hip joint. The anterior}posterior and vertical induced accelerations of the hip