• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.1097-1102
• /
• 2007

This paper describes the development of 6-axis force/moment sensor for an intelligent robot's foot. In order to walk on uneven terrain safely, the foot should perceive the applied forces Fx, Fy, Fz and moments Mx, My, Mz to itself. The applied forces and moments should be measured from a 6-axis force/moment sensor attached to a humanoid robot's foot(ankle). They in the published paper already have some disadvantage in the size of the sensor, the rated output and so on. The rated output of each component sensor (6-axis force/moment sensor) is very important to design the 6-axis force/moment sensor for precision measurement. Therefore, each sensor should be designed to be gotten similar the rated output under each rated load. So, the sensing elements of the 6-axis force/moment sensor should get lots of design variables. Also, the size of 6- axis force/moment sensor is very important for mounting to robot's foot. In this paper, a 6-axis force/moment sensor for perceiving forces and moments in a humanoid robot's foot was developed using many PPBs (parallel plate-beams). The structure of the sensor was newly modeled, and the sensing elements (plate-beams) of the sensor were designed using FEM (Finite Element Method) analysis. Then, the 6-axis force/moment sensor was fabricated by attaching strain-gages on the sensing elements, and the characteristic test of the developed sensor was carried out. The rated outputs from FEM analysis agree well with that from the characteristic test.

• Journal of the Korean Society for Precision Engineering
• /
• v.32 no.4
• /
• pp.359-367
• /
• 2015

The forces and moments exerted on humanoid robot foot are important information for controlling or monitoring the robot. Multi-axis force/moment sensor can be installed under humanoid robot foot to measure forces and moments. The sensor should have large stiffness to support the robot weight and small size not to disturb the motion of the robot. In this paper, we designed a 6-aixs force/moment sensor which has good accuracy, large measuring range, and new compact structure. In addition, the proposed sensor is evaluated using analytical method and FEM(Finite Elements Method) method. Finally, it turned out that it has good performance.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.11a
• /
• pp.161-162
• /
• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.11a
• /
• pp.159-160
• /
• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2009.10a
• /
• pp.297-298
• /
• 2009

• Journal of the Korean Society of Mechanical Technology
• /
• v.20 no.6
• /
• pp.912-916
• /
• 2018

Crawling robots are advantageous in overcoming obstacles. These robots have characteristics such as light weight and outstanding mobility. In case of large robots, they have difficulties passing narrow gaps or entering the cave. In this paper, we propose a milli-scale hexapedal robot using 4-bar linkages. Two conditions are necessary to enable efficient walking. In short, the trajectory of the foot must be elliptical, and the lowest point of the foot should be the same. These conditions are satisfied with a novel leg design. The robot has a pair of three legs and the legs are coupled to operate simultaneously. Each set of the legs are installed to robot's both sides and the legs satisfy the equal lowest foot point and elliptical trajectory. As a result, this hexapedal robot can crawl with 0.56m/s speed.

• Proceeding of EDISON Challenge
• /
• 2016.03a
• /
• pp.424-428
• /
• 2016

This paper presents the kinematics of a walking robot leg based on Jansen mechanism. By using simple mathematics, all trajectories of walking robot leg links can be calculated. A foot point trajectory is used to evaluate the performance of a walking robot leg. Trial and Error method is used to find a best combination of link lengths under certain restrictions. All simulations are performed by Matlab. Ground score, drag score, step size, foot lift, instant speed, and average speed of foot point trajectories are used for selecting the best one.

• Journal of the Korean Society for Precision Engineering
• /
• v.24 no.7 s.196
• /
• pp.90-97
• /
• 2007

This paper describes the development of 6-axis force/moment sensor considered adult weight far an intelligent foot of humanoid robot. In order to walk on uneven terrain safely, the foot should perceive the applied forces Fx, Fy, Fz and moments Mx, My, Mz to itself and control the foot using the forces and moments. The applied forces and moments should be measured from a 6-axis force/moment sensor attached to the foot, which is composed of Fx sensor, Fy sensor, Fz sensor, Mx sensor, My sensor and Mz sensor in a body. Each sensor should get the deferent rated load, because the applied forces and moments to foot in walking are deferent. Therefore, one of the important things in the sensor is to design each sensor with the deferent rated load and the same rated output. In this paper, a 6-axis force/moment sensor (rated load of Fx and Fy are 500Nm and Fz sensor is 1000N, and those of Mx and My are 18Nm, Mz sensor is 8Nm) for perceiving forces and moments in a humanoid robot's foot was developed using many PPBs (parallel plate-beams). The structure of the sensor was newly modeled, and the sensing elements (plate-beams) of the sensor were designed using by ANSYS software (FEM (Finite Element Method) program). Then, a 6-axis force/moment sensor was fabricated by attaching strain-gages on the sensing elements, and the characteristic test of the developed sensor was carried out. The rated outputs from FEM analysis agree well with that from the characteristic test.

• Physical Therapy Rehabilitation Science
• /
• v.11 no.2
• /
• pp.235-244
• /
• 2022

Objective: The aim of this study was to investigate of the foot plantar pressure and usability after gait training using the ExoAtlet wearable exoskeleton robot in an incomplete spinal cord injury (SCI) patient. Design: A case study Methods: Six participants with an asymmetry in motor and sensory function completed the gait training using ExoAtlet wearable exoskeleton robot for 15 sessions, five per weeks, 3weeks. They were divided into two groups (low and high strength group) and group differences were evaluated about session at stating of gait, gait distance at final session and foot plantar pressures and useability after training. Results: Low strength group was faster than high strength group on adaptation of robot gait. And high strength group increased faster than low strength group on the gait distance during training. In standing and gait, weaker leg was higher than stronger leg on mean foot plantar pressure in low strength group. And stronger leg was higher than weaker leg on foot plantar pressure in high strength group. The length of the anterior-posterior trajectory of the center of pressure during gait was similar in low strength group, but different in high strength group. useability was positive about ExoAtlet wearable exoskeleton gait after training. Conclusions: ExoAtlet wearable exoskeleton robot gait training was positive about improving gait in all participants regardless of differences in severity of symptoms and gait abnormalities.

• Journal of Sensor Science and Technology
• /
• v.16 no.3
• /
• pp.211-219
• /
• 2007

This paper describes the development of 6-axis force/moment sensor for a humanoid robot. In order to walk on uneven terrain safely, the robot's foot should perceive the applied forces Fx, Fy, Fz and moments Mx, My, Mz to itself, and be controlled by the foot using the forces and moments. Also, in order to grasp unknown object safely, the robot's hand should perceive the weight of the object using the mounted 6-axis force/moment sensor to its wrist, and be controlled by the hand using the forces and moments. Therefore, 6-axis force/moment sensor should be necessary for a humanoid robot's hand and foot. In this paper, 6-axis force/moment sensor for a humanoid robot was developed using many PPBs (parallel plate-beams). The structure of the sensor was newly modeled, and the sensing element of the sensor was designed using theoretical analysis. Then, 6-axis force/moment sensor was fabricated by attaching strain-gages on the sensing elements, and the characteristic test of the developed sensor was carried out. The rated outputs from theoretical analysis agree well with the results from the experiments.