• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.459-466
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• 2001

The floor vibration aspect for building structures which are in need of large open space are influenced by the interrelation between natural frequency and working loads. Structures with a long span and low natural frequency have a higher possibility of experiencing excessive vibration induced by dynamic excitation such as human activities. These excessive vibrations make the residents uncomfortable and the serviceability deterioration. Need formulation of loads data through actual measurement to apply walking loads that is form of dynamic load in structure analysis. The loads induced by human activities were classified into two types. First type is in place loads. the other type is moving loads. A series of laboratories experiments had been conducted to study the dynamic loads induced by human activities. The earlier works were mainly concerned to parameters study of dynamic loads. In this Paper, the walking loads have been directly measured by using the measuring plate in which two load cells were placed, the parameters, the load-time history of walking loads, and the dynamic load factors have been analyzed. Moreover, the shape of the harmonic loads which were gotten by decomposition the walking loads have been analyzed , and the walking loads modeling have been carried out by composition these harmonic loads derived by functional relation.

• Korean Journal of Applied Biomechanics
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• v.31 no.1
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• pp.50-58
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• 2021

Objective: This study aimed to determine the effect of wrist and trunk weight loading using sandbags in stroke patients in order to provide the quantitative data for enhancement of gait movement. Method: Twelve stroke patients, who have been diagnosed with hemiplegia over a year ago, were participated in this study. All subjects were asked to perform normal walking [N], wrist sandbag walking [W], wrist & trunk sandbag walking [WT], and both wrist sandbag walking [B] and both wrist & trunk sandbag walking [BT], respectively. Eight infrared cameras were used to collect the raw data. Gait parameters, arm swing, shoulder-pelvic kinematics, and lower extremity joint angle were calculated to examine the differences during walking. Results: As a result, there were no significant differences in the gait parameters, shoulder-pelvis, and lower extremities joint angles, but significant differences were found in the range of motion and the anteversion in arm swing. Conclusion: Wrist and trunk weight loading using sandbags affected the movement of the upper extremities only while it did not affect the movement of the lower extremities. It implies that it can reduce the risk of falling caused by a sudden movement change in lower extremities. In addition, the wrist and trunk weight loading using sandbags can induce changes in movement of the upper extremities independently and contribute to functional rehabilitation through resistance training.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.4
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• pp.446-454
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• 2011

In terms of the anatomy and mechanics of the human foot, a flexible robot foot with toes and heel joints is designed for a bipedal walking robot. We suggest three design considerations in determining foot design parameters which are critical for walking stability. Those include the position of the frontal toe, the stiffness of toes and heels, and the position of the ankle joint. Compared with the conventional foot with flat sale, the proposed foot is advantageous for human-like walking due to the inherent structural flexibility and the reasonable parameter values. Simulation results are provided to determine the design parameters and also show that the proposed foot enables smaller energy consumption.

• The Korean Journal of Physiology
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• v.5 no.2
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• pp.29-40
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• 1971

Oxygen consumption, pulmonary ventilation, heart rate, and breathing frequency were measured on 8 men walking on a treadmill carrying load of 9 kg on hand, back, or head. Besides measurements were made on subjects carrying loads of 2.6 kg each on both feet. The speed of level walking was 4, 5, and 5.5km/hr and a fixed speed off km/hr with grades of 0, 3, 6, and 9%. Comparisons were made between free walking without load and walking with various types of loads. The following results were obtained. 1. In level or uphill walking the changes in oxygen consumption, pulmonary ventilation, breathing frequency and heart rate were smallest in back load walking, and largest in hand load walking. The method of back load was most efficient and hand load was the least efficient. The energy cost in head load walking was smaller than that of in hand load walking. It was assumed that foot load costed more energy than hand load. 2. In level walking the measured parameters increased abruptly at the speed of 5.5 km/hr. Oxygen consumption in a free walking at 4 km/hr was 11.4ml/kg b.wt., and 13.1 ml/kg b.wt. 5.5 km/hr, and in a hand load walking at 4 km/hr was 13.9, and 18.8 ml/kg b. wt. at 5.5 km/hr. 3. In uphill walking oxygen consumption and other parameters increased abruptly at the grade of 6%. Oxygen consumption at 4 km/hr and 0% grade was 11.4 ml/kg b. wt., 13.6 at 6% grade, and 16.21/kg b. wt. at 9% grade in a free walking. In back load walking oxygen consumption at 4km/hr and 0% grade was 12.3 ml/kg b.wt.,14.9 at 6% grade, and 18.7 ml/kg b.wt. In hand load walking the oxygen consumption was the greatest, namely, 13.9 at 0% grade, 17.9 at 6%, and 20.0 ml/kg b. wt. at 9% grade. 4. Both in level and uphill walking the changes in pulmonary ventilation and heart rate paralleled with oxygen consumption. 5. The changes in heart rate and breathing frequency in hand load were characteristic. Both in level and uphill walk breathing frequency increased to 30 per minute when a load was held on hand and showed a small increase as the exercise became severe. In the other method of load carrying the Peak value of breathing frequency was less than 30 Per minute. Heart rate showed 106 beats/minute even at a speed of 4 km/hr when a load was held on hand, whereas, heart rate was between, 53 and 100 beats/minute in the other types of load carriage. 6. Number of strides per minute in level walking increased as the speed increased. At the speed floater than 5 km/hr number of strides per minute of load carrying walk was greater than that of free walking. In uphill walk number of strides per minute decreased as the grade increased. Number of strides in hand load walk was greatest and back load walk showed the same number of strides as the free walk.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.5
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• pp.548-552
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• 2015

In this paper, we describe the quadruped walking-control algorithm of the complete full-size humanoid DARPA Robotics Challenge-HUBO (DRC-HUBO) robot. Although DRC-HUBO is a biped robot, we require a quadruped walking function using two legs and two arms to overcome uneven terrains in the DRC. We design a wave-type quadruped walking pattern as a feedforward control using several walking parameters, and we design zero moment point (ZMP) controllers to maintain stable walking using an inverted pendulum model and an observed-state feedback control scheme. In particular, we propose a switching algorithm for ZMP controllers using supporting value and weighting factors in order to maintain the ZMP control performance during foot switching. Finally, we verify the proposed algorithm by performing quadruped walking experiments using DRC-HUBO.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.10a
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• pp.273-280
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• 2000

Building structures which are in need of large open space make the damping effect of the structures decrease greatly. Assembly and office buildings with a lower natural frequency have a higher possibility of experiencing excessive vibration induced by human activities. These excessive vibration make the residents uncomfortable and the serviceability deterioration. The loads induced by human activities were classified into two types. First type is in place loads as like jumping, foot stamping and body bouncing. The other type is moving loads as like walking, running and dancing. A series of laboratories experiments had been conducted to study the dynamic loads induced by human activities, The earlier works were mainly concerned to parameters study of dynamic loads as like activity type, weight, sex, surface condition of structure and etc. In this paper, we have measured directly the walking loads by using the platform. And we have evaluated and analyzed load-time history of walking loads. One of the most important parameter is pacing rate (walking speed) in the walking loads. The difference between the maximum value and minimum value of walking loads depends on the walking speed.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.75-76
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• 2008

In oder for the robot to walk with stability, trajectory generation method for the biped robot is important. In this paper proposed the genetic algorithm to optimize biped robot motion parameters. Because most of trajectory generation, the walking parameters determined arbitrarily. Formulating the constraints of the motion parameters, and the trajectory is derived by cubic spline function. Finally walking patterns are described through simulation studies. When the ZMP(zero moment point) and DSM(dynamic stability margin) are satisfied, the walking pattern is chosen.

• Transactions of Materials Processing
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• v.24 no.3
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• pp.167-175
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• 2015

In the current study, the design methodology has been developed to produce shoe mold for a suitable walking shoes of the general Korean using ANN (Artificial Neural Network). To design the suitable and comfortable shoes for the Korean, the shapes of foots were measured for 513 people. In this research, the foot length, breadth and ankle were considered as design parameters. In order to find the optimal foot shape for the average value of design parameters, the average value of design parameters and the other measurements were used as input and output to the ANN. After training, the various foot measurements were predicted by ANN. Base on the ANN results, the walking shoes were manufactured by considering these measurements and designing a shoe mold. From the results, the proposed method could give a more systematic and feasible means for manufacturing walking shoes with greater usefulness and better generality.

• Korean Journal of Applied Biomechanics
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• v.20 no.4
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• pp.365-372
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• 2010

The purpose of this study were to analyze the changes in kinematic and kinetic parameters and to find biomechanical benefits of Nordic Walking and normal gait performed under the same velocity. Nine participants(age: $26.73{\pm}3.28$ year, height: $182.45{\pm}4.62\;cm$, weight: $76.59{\pm}6.84\;kg$) was chosen. The velocity of gait was set by 5.75 km/h which was made by a Nordic Walking professional. The data were collected by using VICON with 8 cameras to analyze kinematic variables with 200 Hz and force platform to analyze kinetic variables with 2000 Hz. The results of this study were as follows. First, when compared with Normal gait, Nordic Walking group showed decreased Plantarflexion angle and ROM. Second, Nordic Walking group showed decreased knee flexion angle and ROM. Third, Nordic Walking group showed increased hip joint movement. Fourth, Nordic Walking group showed higher active GRF but decreased loading rate from delayed Peak Vertical GRF time and increased impulse. Fifth, Nordic Walking group showed longer ground contact time. Through this study, we found that Nordic Walking showed higher stability and efficiency during gait than normal gait and that Nordic Walking may help people who have walking difficulties.

• Journal of Drive and Control
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• v.13 no.4
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• pp.52-58
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• 2016

The mechanical design for biped walking of a humanoid robot doing the Argentina Tango is presented in this paper. Biped walking has long been studied in the area of robotic locomotion. The aim of this paper is to implement an Argentina Tango dancer-like walking motion with a humanoid robot by using a trajectory generation scheme. To that end, this paper uses blending polynominals whose parameters are determined based on PSO (Particle Swarm Optimization) according to conditions that make the most of the Argentina Tango's characteristics. For the stability of biped walking, the ZMP (Zero Moment Point) control method is used. The feasibility of the proposed scheme is evaluated by simulating biped walking with the 3D Simscape robot model. The simulation results show the validity and effectiveness of the proposed method.