<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7VGhpZ2gmcXVvdDsiIG9yaWdpbmFsX3ZhbHVlPSImcXVvdDtUaGlnaCZxdW90OyIgLz48L2ZpbHRlcnM+PHJhbmdlcyAvPjxzb3J0cz48c29ydCBmaWVsZD0icHVibGlzaGVkIiBvcmRlcj0iZGVzYyIgLz48L3NvcnRzPjxwZXJzaXN0cz48cGVyc2lzdCBuYW1lPSJyYW5nZXR5cGUiIHZhbHVlPSJwdWJsaXNoZWRkYXRlIiAvPjwvcGVyc2lzdHM+PC9zZWFyY2g+" rel="self" type="application/rss+xml" />
    <description></description>
    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>Comfortable Automotive Seat Design and Big Data Analytics: a Study in Thigh Support</title>
      <link>https://trid.trb.org/View/1571014</link>
      <description><![CDATA[This study demonstrates how big data analytics can improve automotive seat design practices pertaining to thigh support and cushion length, a consistent customer complaint across the automotive seating industry. The method featured an analysis of survey feedback (complaint and self-reported anthropometry) obtained from 92,258 buyers of new vehicles in the North American market. Driver seat three dimensional scans from 139 vehicles (representing 12 manufacturers) provided metrics related to cushion length allowing for determination of the percentage of an average occupant's thigh supported by an automotive seat cushion in relation to customer complaints. The range determined to provide thigh support leading to minimal complaints for overall cushion length is 83.46%–88.49% and for cushion length to trim prominence is 73.63%–80.60%. A specific vehicle program was used to confirm the targets established using big data analytics were effective in minimizing customer issues related to thigh support and cushion length.]]></description>
      <pubDate>Mon, 28 Jan 2019 17:11:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1571014</guid>
    </item>
    <item>
      <title>Numerical Investigation of Knee–Thigh–Hip Injuries in Frontal Vehicle Collisions</title>
      <link>https://trid.trb.org/View/1218121</link>
      <description><![CDATA[Recent improvements to occupant restraint systems, such as seat belts and airbags, have caused a shift in the injury profile that results from vehicle collisions from primarily upper body to primarily lower extremity injuries. Injuries of the knee–thigh–hip (KTH) region have been shown to be some of the most debilitating. This project used a finite element model of the KTH region to study injury. A parametric investigation was conducted; the finite element KTH was simulated as a vehicle occupant positioned to a range of precrash driving postures. Results indicated that timing between a significant rise in foot–floor and knee–bolster contact force affected knee kinematics and axial force absorbed by the KTH region. Findings also suggest that introducing a lag time between the respective contacts may decrease the likelihood of KTH bone injury.]]></description>
      <pubDate>Wed, 31 Oct 2012 16:53:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1218121</guid>
    </item>
    <item>
      <title>Vibrotactile “On-Thigh” Alerting System in the Cockpit</title>
      <link>https://trid.trb.org/View/1107788</link>
      <description><![CDATA[Tactile alerts can be a way to direct pilot attention in a way that is easily recognized and difficult to ignore.  This study examined the pilot’s thigh as a placement for vibrotactile display in the cockpit. The authors report initial findings concerning the loci and properties of the display, evaluate the added value of tactile cuing with respect to the existing audio-visual alerting system, and discuss whether the cue should display “flight” or “fight” orienting. Two experiments were conducted.  The first evaluated whether vibrotactile stimulation on the thigh can produce the notion of direction in the vertical plane for a seated operator.  Localization with different burst durations and pulse repetitions were also investigated.  The second experiment examined the added value of vibrotactile directional cues and the effect of the message expressed by the vibrotactile cue: compatible, i.e., fight (toward vibrotactile cue) and inverse, i.e., flight (away from vibrotactile cue).  Results show that vertical directional orienting can be achieved by a vibrotactile display assembled on the thigh. The four-tactor display mode produced more accurate results.  Findings also show that vibrotactile cues should be compatible with the visual alerts and direct the operator toward the way to avoid the hazard.]]></description>
      <pubDate>Fri, 29 Jul 2011 07:45:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1107788</guid>
    </item>
    <item>
      <title>Evaluation of the Field Relevance of Several Injury Risk Functions.</title>
      <link>https://trid.trb.org/View/1104341</link>
      <description><![CDATA[This paper conducted an evaluation of the four injury risk curves proposed in the National Highway Traffic Safety Administration’s New Car Assessment Program (NHTSA NCAP) that are used for estimating the risk of abbreviated injury score (AIS)>= 3 injuries to the head, neck, chest and AIS>=2 injury to the Knee-Thigh-Hip (KTH). As represented in the National Automotive Sampling System (NASS), the predicted injury risk to the four body regions based on driver dummy responses in over 300 frontal NCAP tests were compared against those to drivers involved in real-world crashes of similar severity.  The results described in this paper show that the predicted injury risks to the head and chest were slightly below those in NASS, and the predicted risk for the knee-thigh-hip complex was substantially below that observed in the NASS. The predicted risk for the neck by the Nij curve was greater than the observed risk in NASS by an order of magnitude due to the Nij risk curve predicting a non-zero risk when Nij = 0. An alternative and published Nte risk curve produced a risk estimate consistent with the NASS estimate of neck injury. Similarly, an alternative and published chest injury risk curve produced a risk estimate that was within the bounds of the NASS estimates. No published risk curve for femur compressive load could be found that would give risk estimates consistent with the range of the NASS estimates. This paper recommends that additional work on developing a femur compressive load risk curve be conducted in the future.]]></description>
      <pubDate>Thu, 23 Jun 2011 09:06:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/1104341</guid>
    </item>
    <item>
      <title>Predicting the Effects of Muscle Activation on Knee, Thigh, and Hip Injuries in Frontal Crashes Using a Finite-Element Model with Muscle Forces from Subject Testing and Musculoskeletal Modeling</title>
      <link>https://trid.trb.org/View/1089282</link>
      <description><![CDATA[The authors conducted a previous study and reported on the development of a finite-element model of the midsize male pelvis and lower extremities with lower-extremity musculature that was validated using PMHS knee-impact response data. Knee-impact simulations with this model were performed using forces from four muscles in the lower extremities associated with two-foot bracing reported in the literature to provide preliminary estimates of the effects of lower-extremity muscle activation on knee-thigh-hip injury potential in frontal impacts. In the current study the authors addresses a major limitation of these preliminary simulations by using the AnyBody three-dimensional musculoskeletal model to estimate muscle forces produced in 35 muscles in each lower extremity during emergency one-foot braking. To check the predictions of the AnyBody Model, activation levels of twelve major muscles in the hip and lower extremities were measured using surface EMG electrodes on 12 midsize-male subjects performing simulated maximum and 50% of maximum braking in a laboratory seating buck. Comparisons between test results and the predictions of the AnyBody Model when it was used to simulate these same braking tests suggest that the AnyBody model appropriately predicts agonistic muscle activations but under predicts antagonistic muscle activations. Simulations of knee-to-knee-bolster impacts were performed by impacting the knees of the lower-extremity finite element model with and without the muscle forces predicted by the validated AnyBody Model. Results of these simulations confirm previous findings that muscle tension increases knee-impact force by increasing the effective mass of the KTH complex due to tighter coupling of muscle mass to bone. They also indicate that muscle activation preferentially couples mass distal to the hip, thereby accentuating the decrease in femur force from the knee to the hip. However, the reduction in force transmitted from the knee to the hip is offset by the increased force at the knee and by increased compressive forces at the hip due to activation of lower-extremity muscles. As a result, approximately 45% to 60% and 50% to 65% of the force applied to the knee is applied to the hip in the simulations without and with muscle tension, respectively. The simulation results suggest that lower-extremity muscle tension has little effect on the risk of hip injuries, but it increases the bending moments in the femoral shaft, thereby increasing the risk of femoral shaft fractures by 20%-40%. However, these findings may be affected by the inability of the AnyBody Model to appropriately predict antagonistic muscle forces.]]></description>
      <pubDate>Thu, 20 Jan 2011 11:22:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1089282</guid>
    </item>
    <item>
      <title>Validation of a Biofidelic LS-DYNA Model and Comparison vs. a Traditional ATD Finite Element Model for Assessing Knee-thigh-hip Injuries</title>
      <link>https://trid.trb.org/View/1082070</link>
      <description><![CDATA[This article presents an enhanced Finite Element (FE) model of the human Knee-Thigh-Hip (KTH) as a reliable mean for the prediction of bone failure mechanism for a frontal knee impact. Improvements made to the original model are reported and the model is validated against a cadaver sled test. An identical finite element impact event was replicated with use of the Livermore Software Technology Corporation (LSTC) dummy. The main terms of comparison were the axial femur force and the possibility of locating a potential bone fracture in the lower extremity. The KTH model gave more reliable results than the dummy model in terms of fracture prediction.]]></description>
      <pubDate>Mon, 29 Nov 2010 07:39:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/1082070</guid>
    </item>
    <item>
      <title>Injury patterns in frontal crashes: The association between knee-thigh-hip (KTH) and serious intra-abdominal injury</title>
      <link>https://trid.trb.org/View/906422</link>
      <description><![CDATA[Safety belts protect occupants in frontal impacts by reducing occupant deceleration and preventing the occupant from hitting interior vehicle components likely to cause injury. However, occupants moving forward during the impact may contact the safety belt webbing across their chest and abdomen. We hypothesized that if the occupant loaded their knee-thigh-hip (KTH) region with enough force to result in injury to this region--it might prevent compression (and injury) of their abdomen by the safety belt. Crash Injury Research and Engineering Network (CIREN) data were used to test the association between KTH and intra-abdominal injury related to safety belts. Odds ratios with 95% confidence limits (CL) and logistic regression models were used to assess statistical significance. Analyses were based on 706 CIREN adult, front seat occupants using their safety belt and injured in frontal crashes. Occupants with KTH injury were four times less likely (adjusted odds ratio = 0.25, 95% CL 0.10, 0.62) to have concomitant serious intra-abdominal injury caused by the safety belt. Although safety belts save lives and prevent serious injury, some occupants may sustain serious intra-abdominal injury when the abdomen is loaded by the safety belt during a frontal impact. These results may be useful to motor vehicle manufacturers and others who design and test motor vehicle safety systems.]]></description>
      <pubDate>Tue, 22 Dec 2009 08:57:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/906422</guid>
    </item>
    <item>
      <title>Development of a finite element model of the knee-thigh-hip of a 50th percentile male including ligaments and muscles</title>
      <link>https://trid.trb.org/View/896238</link>
      <description><![CDATA[An LSDYNA finite element model of the knee-thigh-hip (KTH) of a 50th percentile male was developed for exploring mechanics of injuries to the KTH during frontal crashes. This includes a model of the geometry of bones and also discrete element representations of ligaments and muscles of the KTH. The model was validated using physical tests obtained from the National Highway Traffic and Safety Administration's (NHTSA) test database. Validation of individual components like the upper femur, femoral condyles and pelvis were performed and compared to similar physical tests. The results were used to verify geometry, material properties and failure mechanisms of bone materials. Validations were also performed against a whole-body cadaver test to verify contributions of passive muscle and ligament forces. Failure mechanisms in the tests and simulations were compared to ensure the model provides a useful tool for exploring fractures in the KTH resulting from frontal vehicle crashes.]]></description>
      <pubDate>Thu, 30 Jul 2009 13:48:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/896238</guid>
    </item>
    <item>
      <title>Development of a Finite Element Model to Study the Effects of Muscle Forces on Knee-Thigh-Hip Injuries in Frontal Crashes</title>
      <link>https://trid.trb.org/View/888273</link>
      <description><![CDATA[To study the potential effects of muscle tension on knee-thigh-hip (KTH) injuries due to knee bolster loadings in frontal crashes, a finite element (FE) model with KTH and lower-extremity muscles has been developed.  This model was developed by remeshing the MADYMO human lower-extremity FE model to account for regional differences in cortical bone thickness, trabecular bone, cortical bone with directionally dependent mechanical properties and Tsai-Wu failure criteria, and articular cartilage.  The model includes 35 Hill-type muscles in each lower extremity with masses based on muscle volume.  The skeletal response of the model was validated by simulating biomechanical tests without muscle tension, including cadaver skeletal segment impact tests documented in the literature as well as recent tests of seated whole cadavers that were impacted using knee-loading conditions similar to those produced in Federal Motor Vehicle Safety Standard (FMVSS) 208 testing.  Simulations of knee-to-knee-bolster impacts conducted with and without different levels of lower-extremity muscle activation reported in the literature for braking/bracing suggest that muscle tension has the potential to decrease the externally applied force required to cause KTH fracture, and the potential to increase the likelihood of femoral shaft fracture relative to hip fracture by increasing bending moments in the femoral shaft.  More reliable and complete data are needed to confirm this effect of muscle tension and before the overall effects of muscle tension on KTH injury can be determined.]]></description>
      <pubDate>Mon, 04 May 2009 10:43:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/888273</guid>
    </item>
    <item>
      <title>Impact Response and Biomechanical Analysis of the Knee-Thigh-Hip Complex in Frontal Impacts with a Full Human Body Finite Element Model</title>
      <link>https://trid.trb.org/View/888274</link>
      <description><![CDATA[A finite element model (FEM) of the human body was used to simulate occupant knee impacts experienced in frontal crashes.  The model includes detailed anatomical features of the head, neck, shoulder, chest, thoracic and lumbar spine, abdomen, pelvis, and lower and upper extremities.  The material properties used in the model for each anatomic part of the human body were obtained from test data reported in the literature.  The model used in the current study has been previously validated in frontal and side impacts, and was further validated with cadaver knee-thigh-hip (KTH) impact tests in the current study.  This FEM was used to study the effects of impactor configuration and flexion angle of the knee on biomechanical impact responses of the KTH complex.  The study showed that the knee flexion angle and the impact direction and shape of the impactors affected the injury outcomes of the KTH complex significantly.  The 60-degree flexed knee impact showed the least impact force, knee pressure, femoral von Mises stress, and pelvic von Mises stress but largest relative displacements of the Posterior Cruciate Ligament (PCL) and Anterior Cruciate Ligament (ACL).  The 90-degree flexed knee impact resulted in a higher impact force, knee pressure, femoral von Mises stress, and pelvic von Mises stress; but smaller PCL and ACL displacements.  Stress distributions of the patella, femur, and pelvis were also given for all the simulated conditions.]]></description>
      <pubDate>Mon, 04 May 2009 10:43:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/888274</guid>
    </item>
    <item>
      <title>Characterization of Knee-Thigh-Hip Response in Frontal Impacts Using Biomechanical Testing and Computational Simulations</title>
      <link>https://trid.trb.org/View/888267</link>
      <description><![CDATA[Knowledge of the force transmitted from the knee to the hip under knee impact loading is required to develop and validate crash test dummies and computational models that are capable of predicting the risk of injury to all parts of the knee-thigh-hip (KTH) complex in frontal impacts.  Knee impact responses of whole and segmented cadavers were measured over a wide range of knee loading conditions.  These data were used to develop and help validate a computation model, which was used to estimate force transmitted to the cadaver hip.]]></description>
      <pubDate>Mon, 04 May 2009 10:43:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/888267</guid>
    </item>
    <item>
      <title>Development of a Finite Element Model for Flex-PLI</title>
      <link>https://trid.trb.org/View/815211</link>
      <description><![CDATA[A finite Element (FE) model of the next-generation flexible pedestrian leg-form impactor (Flex-PLI) developed by the Japan Automobile Manufacturers Association (JAMA) and Japan Automobile Research Institute (JARI) was developed in this study. The Flex-PLI is intended to be used in evaluating safety of car front structures against the lower limbs of pedestrians. A 3D geometry of each part was reproduced in PAM-CRASHTM based on drawings of the Flex-PLI. For material characterization, the stress-strain characteristics were determined from the results of the material tests on each individual component, with the strain rate dependency of the material taken into account. The results of the dynamic 3-point bending test for the thigh and leg and the dynamic 4-point bending test for the knee joint performed by JARI were used to validate the model. The validation results showed that the computer simulation results for the force-deflection response of the thigh and leg as well as the moment-angle response of the knee joint agreed well with the test results. Impact tests against vehicles at 40 km/h were reproduced using the model, and the results were compared with the test results. The results of the comparison showed that the kinematics of the Flex-PLI could be reproduced by the computer simulation. It was also found that the bending moment of the thigh and leg as well as the elongation of the ligament cables of the knee joint could be accurately reproduced.]]></description>
      <pubDate>Wed, 12 Sep 2007 16:31:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/815211</guid>
    </item>
    <item>
      <title>Development of a Biofidelic Flexible Pedestrian Legform Impactor</title>
      <link>https://trid.trb.org/View/809101</link>
      <description><![CDATA[This paper describes the results of biofidelity evaluation for the leg, thigh, and knee joint of the Biofidelic Flexible Pedestrian Legform Impactor (Flex-PLI) and reports on the detailed measurement systems and specifications of the Flex-PLI.  The Flex-PLI simulates human knee joint stiffness and human bone flexibility correctly.  The Flex-PLI is developed in this study, as an aid in the assessment of vehicle measures used to protect the lower extremities of pedestrians during a pedestrian accident.]]></description>
      <pubDate>Fri, 25 May 2007 10:36:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/809101</guid>
    </item>
    <item>
      <title>Derivation and Theoretical Assessment of a Set of Biomechanics-Based, AIS2+ Risk Equations for the Knee-Thigh-Hip Complex</title>
      <link>https://trid.trb.org/View/806202</link>
      <description><![CDATA[The probability of sustaining a moderate-to-serious knee-thigh-hip complex (KTH) injury in a frontal crash was estimated using a specially derived set of risk equations in a four-part study. After literature with data on knee-loaded, whole-body, post-mortem human subjects (PMHS) was collected, normalization of attendant response data (such as axial compressive load knee applications) to those of a mid-sized male occurred. A set of risk equations for adults of varying genders and ages was derived using numerous mathematical constructs and statistical analyses. Analysis of National Automotive Sampling System field data occurred for purposes of comparison. Resulting risk equation set fidelity assessment transformed axial compressive femur loads into event risks from simulated, full-engagement frontal crashes. Field-based injury rates were compared with resulting model-based injury rates, with promising results. The average model-based injury rate was 1.10% and the field-based rate was 1.30% in towaway frontal crashes involving unbelted drivers in 1985-1997 model year passenger cars with less than 58 km/h speed changes. The model confirmed some field trends, such as higher rates of KTH injuries in males than females. Better fidelity for lower-speed crashes than higher-speed were demonstrated through risk equations.]]></description>
      <pubDate>Thu, 19 Apr 2007 15:55:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/806202</guid>
    </item>
    <item>
      <title>Influence of Age-Related Stature on the Frequency of Body Region Injury and Overall Injury Severity in Child Pedestrian Casualties</title>
      <link>https://trid.trb.org/View/793083</link>
      <description><![CDATA[This article describes research examining the frequency of body region injury and overall severity of injury in children, based on age-related stature. The authors examined trauma registry data, including coded injuries, for 1,590 child pedestrians aged from 1- to 15-years-old. The injured children, all treated at a level-one trauma center, were categorized by stature relative to age (1-3, 4-6, 7-9, 10-12, 13-15 years) and body region (head and face, neck, thorax, abdomen and pelvic content, thoracic and lumbar spine, upper extremities, pelvis, and lower extremities). Lower extremities were sub-divided into three sub-structures (thigh, leg, and knee). Child pedestrian injuries, for each age group and body region, were placed in a severity level on the Abbreviated Injury Scale (AIS) and compared between age groups using appropriate significance tests. The authors concluded that while child pedestrian injuries appeared to be relatively constant across age and stature ranges, height seemed to influence the frequency of injury to individual body regions, including the thorax and lower extremities.]]></description>
      <pubDate>Fri, 10 Nov 2006 12:01:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/793083</guid>
    </item>
  </channel>
</rss>