• Journal of the Korean Society of Physical Medicine
• /
• v.8 no.4
• /
• pp.567-571
• /
• 2013

PURPOSE: This study find out the effect of torque and power through various solidity of mouth guard on shoulder flexion and extension. METHODS: This study was conducted with healthy adults in their 20s Korean. Cybex system was used to measure the torque and power fo shoulder joint flexion/extension during isokinetic contraction when the various solidity mouth guard was used and no mouth guard was used. RESULT: The results of this study were summarized as follows: relative torque and average power was showed significantly difference between non applying mouth guard and applying hard type mouth guard during shoulder flexion and extension at isokinetic contraction. CONCLUSION: The application of hard type mouth guard was increased torque and power in joint of body. which may be clinically useful.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.10a
• /
• pp.203-204
• /
• 2012

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.3
• /
• pp.385-392
• /
• 1997

The joint design and manufacture of the composite structure have become an important research area because the structural efficiency of the composite structure is often determined by its joint not by its basic structure. The co-cured joint is an efficient joint technique because both curing and jointing for composite structures are achieved simultaneously. In this paper, the torque capacities of the co-cured tubular lap joint with and without knurling of the pyamid type were experimentally measure. From the experimental resuts, it was found that the excess resin played a role as an adhesive in the co-cured tubular lap joint whose steel adherends were not knurled. Also, it was found that the torque capacity of the co-cured joint was increased as the knurling size of the pyramid type on the surface of the steel adherend was increased.

• The Journal of Korean Academy of Prosthodontics
• /
• v.47 no.2
• /
• pp.125-135
• /
• 2009

Statement of problem: Loosening or fracture of the abutment screw is one of the common problems related to the dental implant. Generally, in order to make the screw joint stable, the preload generated by tightening torque needs to be increased within the elastic limit of the screw. However, additional tensile forces can produce the plastic deformation of abutment screw when functional loads are superimposed on preload stresses, and they can elicit loosening or fracture of the abutment screw. Therefore, it is necessary to find the optimum tightening torque that maximizes a fatigue life and simultaneously offer a reasonable degree of protection against loosening. Purpose: The purpose of this study was to present the influence of tightening torque on the implant-abutment screw joint stability with the 3 dimensional finite element analysis. Material and methods: In this study, the finite element model of the implant system with external butt joint connection was designed and verified by comparison with additional theoretical and experimental results. Four different amount of tightening torques(10, 20, 30 and 40 Ncm) and the external loading(250 N, $30^{\circ}$) were applied to the model, and the equivalent stress distributions and the gap distances were calculated according to each tightening torque and the result was analyzed. Results: Within the limitation of this study, the following results were drawn; 1) There was the proportional relation between the tightening torque and the preload. 2) In case of applying only the tightening torque, the maximum stress was found at the screw neck. 3) The maximum stress was also shown at the screw neck under the external loading condition. However in case of applying 10 Ncm tightening torque, it was found at the undersurface of the screw head. 4) The joint opening was observed under the external loading in case of applying 10 Ncm and 20 Ncm of tightening torque. 5) When the tightening torque was applied at 40 Ncm, under the external loading the maximum stress exceeded the allowable stress value of the titanium alloy. Conclusion: Implant abutment screw must have a proper tightening torque that will be able to maintain joint stability of fixture and abutment.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.2248-2253
• /
• 2005

Although the progress in bipedal walking is impressive in recent years, biped robots still require very high torque and can walk only for a short time interval with their internal batteries. Therefore, further research needs to be carried out to enhance walking efficiency of these robots. In order to achieve this goal, we attempt to imitate human walking with pelvis and waist joint rotations in the frontal plane. In order to investigate the effect of the pelvis and waist joint rotations in the frontal plane motion, we study the frontal plane model with a triangular structure made up of a waist joint and two hip joints. Through simulation, we show that the pelvis rotation can reduce the maximum torque and the control effort, and the waist joint rotation can reduce the trunk sway caused by the pelvis rotation. The combination of these two rotations makes the bipedal walking in the frontal plane more efficient.

• Korean Journal of Applied Biomechanics
• /
• v.17 no.1
• /
• pp.61-68
• /
• 2007

The purpose of this study was to analyze the shoulder joint torque and muscle pattern performing as Tennis serve by Isokinetic motions on Isomed 2000. The subject, who was 5 males Korean national high school tennis players. By analyzing the flexion/extension of the shoulder, the peak torque of the internal/external rotation motion(at 60,180 and 300 degree/sec) at peak torque degree, the weight, peak torque, and power. combined with the timing of the electrode of the attached trapezius and posterior deltoid at the three part. From the data analysis & discussion the following conclusions were drawn. When doing a shoulder extension, the peak torque can be widely seen at 60degree per second. However the degree may be different depending on angular velocity. When doing an internal rotation at 90degree abduction, peak torque per weight was seen at 60degree per second. The degree of peak torque was at 31.6-44.2 and peak power was faster when angular velocity was increased. The aspect of muscle pattern was seen more at the internal rotation in the 90degree abduction rather than the shoulder extension. However the angular velocity was not influenced by muscle mobilization(in order of anterior deltoid, posterior deltoid and trapezius. To properly apply the above conclusion, when tennis players serve it is better the elbow be impacted by the extension. when doing isokinetic motion it is better to increase angular velocity and improve muscle power. also the anterior deltoid amongst the shoulder muscle should be improved to develop serve speed.

• Proceedings of the KIEE Conference
• /
• 1989.11a
• /
• pp.445-449
• /
• 1989

Achievement of a straight line motion in the Cartesian space has a matter of great importance. Minimization of task execution time with linear interpolation in the joint space, accomplishing of a approximation of straight line motion in the Cartesian coordinate is considered as the prespecified task. Such determination yields minimum time joint-trajectory subject to input torque constraints. The applications of these results for joint-trajectory planning of a two-link manipulator with revolute joints are demonstrated by computer simulations.

• Proceedings of the KIEE Conference
• /
• 2004.07d
• /
• pp.2420-2422
• /
• 2004

In this paper, we developed a miniaturized humanoid having the new joint mechanism. In general, the high torque actuator and the joint mechanism having three coincided axes are important in development of the miniaturized humanoid. By using the swash plate, which is generally used in three axes rotor mechanism, we developed a new three-coincided-axes joint mechanism and a miniaturized humanoid having the joint mechanism at its hip and ankle joints. Since the joint mechanism has a pair of parallel drive motors for each axis, the driving torque of the joint mechanism is very high. Futhermore, thanks to the three-coincided-axes mechanism, the solution of the inverse kinematics is simple and computationally efficient, and the resulting walking behavior of the humanoid becomes natural.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.1
• /
• pp.53-67
• /
• 1996

The dynamic characteristics of mechanical structure are strongly affected by the properties of joint parameters. In this study, the test structures are constructed with two beams which are clamped by bolts, and a bolted joint which is modelled as a lumped stiffness element. To idientify the dynamic joint parameters with variance of clamping torque of bolts, the sensitivity analysis and the mode energy analysis methods are investigated experimentally. As a reult of these two methods, stiffnesses of bolted joint are experimentally found to increase as the clamping torque increases. These stiffnesses identified from the sensitivity analysis and the mode energy analysis method have some difference.

• International Journal of Control, Automation, and Systems
• /
• v.6 no.2
• /
• pp.234-242
• /
• 2008

The purpose of this paper is to verify the practical effectiveness of an interphalangeal coordination-based joint motion planning method for humanoid finger operations. For the purpose, several experiments have been performed and comparative experimental results are shown. Through the experimental works, it is confirmed that according to the employed joint motion planning method, the joint configurations for a finger's trajectory can be planned stably or not, and consequently the actual joint torque command for controlling the finger can be made moderately or not. Finally, this paper analyzes that the interphalangeal coordination-based joint motion planning method is practically useful for implementing a stable finger manipulation. It is remarkably noted that the torque pattern by the method is well-balanced. Therefore, it is expected that the control performance of humanoid or prosthetic fingers can be enhanced by the method.