Robot Modeling and Simulation
Soft and Flexible Robot
1. Simulation of Walking with Walking Assistant Machine (2006~2008):
The bipedal humanoid robot WABIAN-2R was developed to be used as a human motion simulator. One of its purposes is to be used in testing assistive devices instead of using real human. WABIAN-2R was successfully been used to perform walking with Walking Assistant Machine. However, the assistant machine was not active, which enable the robot to push the device without facing any resistance in terms of reaction force. Therefore, this research is conducted to check the effect of external forces on the robot walking motion.
The research was conducted in a simulation based through developing a dynamic simulation to analyze the robot walking with the walking assistance machine. The research resulted in development of a control method for the walking device. Moreover, the walking behavior was realized when the robot push the walking assistant machine.
2. Semi-Passive Dynamic Walking (2008~2015):
The bipedal robot requires high energy consumption in order to perform walking locomotion. One of the reasons for the high energy consumption is the use of large drivable gear system in the leg joints, which makes the leg weight very high. Moreover, large gear mechanisms reduce the output power due to the power lost during motion. In order to reduce energy consumption we propose to simplified joint mechanism with some elastic elements. Developing some techniques the robot will be able to perform walking locomotion with passive rotational motion in the ankle pitch joint. This help to reduce the energy used during the walking motion. After a successful test for performing bipedal walking with less energy consumption on computer simulation, we are currently developing a new mechanical design for the ankle pitch joint. The newly developed mechanism have the capability to provide active and passive motion. Using this mechanism the robot will be able to perform passive dynamic walking as well as active walking in case fully control of the leg is needed.
3. Bipedal locomotion on different gravity (2009~2013):
The aim of the research is to check the effect of the gravity on the biped locomotion, and developing some methods to overcome the problems that might be face when walking on different gravity than earth gravity. In case of low gravity the walking gait could not be fully applicable for locomotion;therefore, developing of running gait locomotion is needed. Some simulation experiments of robot walking on moon gravity were conducted . The simulation result shows the walking motion become unstable due to low gravity. When the walking velocity is decrease the stability of walking motion increases.
4. Development of a Robotic Hand System for Surgical Application (2015 ~ now):
The objective of the research is to develop a robotic hand system that can be used in surgical applications. Laparoscopic surgery has been widely used in many surgical operations. It has many advantages over traditional surgical techniques in terms of smaller cut that leads to shorter recovery periods. However, there are some limitations to this technique such as the absence of the tactile sense, and the difficulty of eye-hand coordination. Therefore, HALS (Hand Assisted Laparoscopic Surgery) was developed to overcome those limitations. HALS is performed by inserting one hand into the patient's body. There are some risks when using HALS such as causing injury to the patient of suffering from fatigue due to holding the arm posture for a long time. The proposed system is aiming to replace the surgeon's hand with a robot hand mechanism that can be controlled by the user from outside. Moreover, the robot hand is equipped with force sensors that will transfer the tactile sensations to the user's hand throw a haptic device.