Recently, diseases in gastro-intestinal tract have drastically increased. As a result, endoscopic technologies are being developed to diagnose and treat these diseases. Biomaterial property is essential information to develop endoscopic devices especially capsule type endoscope. For the past decades, experiments to obtain material property of gastro-intestinal tract are performed on in-vitro state. Therefore, material properties of digestive organs are not in-vivo test result but in-vitro result. In this research, we design, develop, and fabricate a bio-material property measurement (BMPM) system. The measuring system consists of a probing device, tendon device and suction part. The probe measures the force transmitted from the biomaterial as the sensing module protrudes based on the tendon controls, while the suction device seizes the organ. By using the system, we can measure the local deformation force and the piercing force. The measured deformation and piercing force data can be used for the locomotive and clamping mechanism design of the capsule type endoscope. In order to evaluate the validity of the BMPM, we perform the operation in an esophagus, stomach and colon of a pig. In conclusion, we could measure each organ's material properties under in-vitro state without dissection of digestive organs. Some in-vivo test results are expected to design endoscopic devices using the proposed BMPM system.

There is a growing tendency to use the Internet as the transmission medium of the telerobotic system since the Internet is inexpensive and available all over the world. However, the bilateral real-time teleoperation can be unstable due to the random time delays of the Internet. The event-based teleoperation is one of the fine approaches to overcome the ransom time delays. Since the event based control uses a non-time action reference, the stability and response performance of the system are affected by the time, which an event is held for. This study introduces the variable holding time to secure stability and response performance at once. The proper holding time for each event is obtained depending on the characteristics of the task through the fuzzy logic. The proposed control scheme was implemented on a robot arm over the Internet to show its effectiveness.

Sliding control guarantees system performance in the presence of modeling uncertainties and parameter inaccuracies. However this is obtained at the price of high control activity that may exacerbate chattering. As one way to alleviate this problem a continuation method using a boundary layer around switching is usually used. In this case selecting the control bandwidth and boundary layer thickness is a crucial problem for the trade-off between sliding performance and chattering. The parameter tuning is usually done by trial-and-errors in practice causing significant effort and time. An auto-tuning method based on fuzzy rules is suggested. To this end, the tracking error index and chattering index are defined first and then the fuzzy rules are designed to compromise the error and chattering indices. To demonstrate the efficiency of the proposed method a robotic control system is simulated and tested. It is shown that the proposed algorithm is effective to facilitate the parameter tuning for sliding mode controllers.

Optimal task sequence planning using a simulated annealing technique is developed for a high throughput chip placement machine. To minimize tact time, chips are mounted by multiple robots on moving PC boards being transferred by a precision conveyer. To avoid both geometric and dynamic interferences among multiple robots, while minimizing the tact time, the sequence of operations as well as the allocation of the multiple robots are optimized by using simulated annealing. The optimization problem is a type of traveling salesman problem, but is highly complicated because the target destinations for placing individual chips keep moving together with the PC board. First, the configuration of the new chip placement system is described. The task sequence optimization problem is then formulated, followed by the application of simulated annealing to solving the problem. An efficient algorithm for perturbing a task sequence is developed and applied to practical chip placement tasks.>

An integrated approach to the concurrent design of arm structure and control is presented. To achieve high-speed positioning, a technique is developed in which comprehensive design parameters describing arm link geometry, actuator locations, and feedback gains are optimized with respect to the settling time of the system. First, a two-link, nonrigid arm is analyzed, and a simple dynamic model representing rapid positioning processes is obtained. A PD control system is designed for the dynamic model. Optimal feedback gains minimizing the settling time are obtained as functions of structural parameters involved in the dynamic model. The structural parameters are then optimized by using an optimization technique in order to obtain an overall optimal performance. The resultant arm design shows an outstanding performance, which is unattainable if the structure and control are designed separately.>

The integrated structure/control design of flexible robot arms is presented. The open loop, poles, and zeros are relocated by modifying the geometry and the structure of the arm. To determine the geometry and structure in a systematic manner, an inverse mapping method based on finite-element modeling and sensitivity analysis is applied to the flexible arm design. Using this method, a beam geometry that allows for a significantly high natural frequency is obtained. In order to relocate zeros, the torque transmission technique is applied. It makes it possible to remove nonminimum-phase zeros and make the endpoint control robustly stable. Based on the theoretical analysis and computation, a prototype arm was designed and built, and its performance was evaluated.>

A flexible arm with a special transmission mechanism is analyzed, and a method for integrated design of the arm structure and controller is presented. Control of flexible arms is a difficult problem because of the complicated dynamic coupled with the nonminimum-phase nature which is due to the noncollocated construction of sensor and actuator. The transmission mechanism developed relocates the torque-actuation point on the arm and modifies the flexible arm to a minimum-phase system. The resulting flexible arm is analyzed in terms of poles and zeros that are changed by relocating the torque-actuation point. A simple prototype arm is designed and compared with a nonminimum-phase arm. The effectiveness of the special transmission is discussed with regard to control performance, and an integrated structure/control design methodology is proposed.>