• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.446-449
• /
• 2002

Quadruped walking robot requires dynamic control to keep its stability in high speed walking. To keep its walking stability by control of only legs' Joint angle lowers energy efficiency. It is known that an animal or a human use the moving of the mass center of one's upper body to keep the stability. We have developed a quadruped walking robot with weight balancing oscillator that have high energy efficiency. In this study, walking tests are performed for the robot to verify the validity of the weight balancing oscillator.

• Journal of Veterinary Clinics
• /
• v.35 no.5
• /
• pp.247-249
• /
• 2018

A 3-year-old black Thoroughbred colt weighing 500 kg was admitted to the Equine Hospital of Korea Racing Authority (KRA) due to the chronic gait abnormality of the hindlimbs. The history revealed that the patient had run and fallen onto the fence of the farm about at the age of 1 year old and the lameness had been worsening insidiously since the accident. The degree of lameness was 2/5 in accordance with the AAEP lameness grading system in both hindlimbs at hand walking and trot. The lameness was exacerbated at lunging clockwise and counterclockwise on both hindlimbs. The definitive diagnosis of the bilateral osteoarthritis of coxofemoral joint was established using radiography under general inhalation anesthesia. The prognosis was considered to be poor with low expectancy for racing and the colt was expelled from the racecourse eventually. The clinicians are required to consider the possibility of osteoarthritis of coxofemoral joint presented with chronic hindlimb lameness although it is rare. This is the first report on the bilateral osteoarthritis coxofemoral joint in Republic of Korea.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.8
• /
• pp.264-273
• /
• 2013

The importance of the robots has emerged as the means of minimizing the casualties in the future war, and, thus, the biomimetic robots mimicking the optimized organisms has been actively studied. The robot inspired lizard is suitable for reconnaissance and the surveillance in narrow areas. In this paper, we analyzed the locomotion of a lizard by motion capture system using the infrared markers. We attached 21 markers to the joints of the lizard. By considering the measured data, we analyzed the walking motion of the lizard which trots in a sprawled posture. Moreover, we proposed the 25 dof kinematic model which was able to reproduce the gait of the lizard faithfully. The model was verified by simulations.

• The Journal of Korea Robotics Society
• /
• v.18 no.2
• /
• pp.172-181
• /
• 2023

This paper presents research on the stability of control for a quadruped robot with two different leg structure designs. The focus of the research is on the design and analysis of the leg structures in terms of their impact on the stability and robustness of the robot's motion. First, a static analysis was performed in the simulation to compare the structural strength of the legs when the same force was applied. Secondly, two quadruped robots were built, each equipped with differently designed legs, and performed trot gait walking in the real world. And the states of the robots and the torques of each joint were analyzed and compared. In conclusion, based on the results of structural analysis in simulation and the actual walking experiments with the robots, it was demonstrated that the legs designed to be structurally robust improved the control stability of the quadruped robot.

• Journal of Veterinary Clinics
• /
• v.22 no.1
• /
• pp.21-25
• /
• 2005

This study was performed to assess therapeutic effect of the tibial plateau leveling osteotomy (TPLO) in dogs with experimentally transected cranial cruciate ligaments (CrCL). Nine healthy adult Beagle dogs were transected left CrCL under general anesthesia. The dogs were assigned to TPLO and non-TPLO control groups. The TPLO procedures for correcting the CrCL rupture in the left stifle of dogs were performed under sterile conditions. Before TPLO procedures, all dogs were screened by orthopedic and radiographic examinations. Dogs were lameness free for the previous three months, and when examined at the walk and trot on a hard surface, in a straight line and on a circle. Lateral and craniocaudal radiographs were done to confirm the soundness of the both knee joint in dogs and not detectable lesions were diagnosed. The dogs were intravenously injected with a 10 mci/kg of 99mTechnetium-methylene diphosphonate (99mTc-MDP) under general anesthesia. Scintigraphs were obtained using a large field of view gamma camera equipped a parallel-hole, low-energy about 3 hours after intravenous injection of 99mTc-MDP. Before CrCL transection and 4, 8, and 12 weeks after the procedures, scintigraphy were conducted. Bone uptake of the left stifle joint increased after the procedures in all dogs. When the bone uptake from the TPLO procedure was compared with that of the control, there was a significant difference (p < 0.05). At 12 weeks after the TPLO procedure, the dogs showed normal anatomical posture and gait. It is concluded that TPLO procedure was effective in reconstruct of the stifle joint in dogs with CrCL rupture.