Computer topography (CT) imaging is one of the powerful-tools for nondestructive observation technique. In this paper, we present observation of bone from mice by scanning electron microscope (SEM)-CT system using env...
详细信息
Computer topography (CT) imaging is one of the powerful-tools for nondestructive observation technique. In this paper, we present observation of bone from mice by scanning electron microscope (SEM)-CT system using environmental- SEM (E-SEM). The advantage of this SEM-CT system is able to image in high-resolution with less than 400 nm resolution. We investigated the effects of X-ray wavelengths and intensities to improve the imaging contrast for SEM-CT observation. From experimental results, a porous structures were observed inside the bone sample with approximately 10 μm pores.
This paper describes the identification of the humanoid robot TORO using two methods: the classical joint torque based identification, and the more recent base-link approach. In our past research we have developed an ...
详细信息
This paper describes the identification of the humanoid robot TORO using two methods: the classical joint torque based identification, and the more recent base-link approach. In our past research we have developed an identification method for dynamics identification of humanoids using only the external forces because most humanoid robots are not equipped with torque sensors, and using the motor current requires a precise model of the transmission. With TORO it is now possible to measure the pure joint torque and thus to compare the efficiency of both methods for humanoid robots. This paper compares the joint torque measured by the torque sensor and the joints torque predicted by the inverse dynamics, using the identified dynamic parameters as well as the contact forces measured with the ankle force torque sensors and the predicted one using the dynamics model and the identified parameters. We discuss how the identified parameters differs using each method both with direct validation and cross validation.
Path planning in unknown environments is one of the most challenging research areas in robotics. In this class of path planning, the robot acquires the information from its sensory system. Sampling-based path planning...
Path planning in unknown environments is one of the most challenging research areas in robotics. In this class of path planning, the robot acquires the information from its sensory system. Sampling-based path planning is one of the famous approaches with low memory and computational requirements that has been studied by many researchers during the past few decades. We propose a sampling-based algorithm for path planning in unknown environments using Tabu search. The Tabu search component of the proposed method guides the sampling to find the samples in the most promising areas and makes the sampling procedure more intelligent. The simulation results show the efficient performance of the proposed approach in different types of environments. We also compare the performance of the algorithm with some of the well-known path planning approaches, including Bug1, Bug2, PRM, RRT and the Visibility Graph. The comparison results support the claim of superiority of the proposed algorithm.
Recent technological advancements in cardiovascular surgery such as transapical transcatheter aortic valve implantation (TA-TAVI) enabled treatment to elderly that were initially declined surgery. However, valve malpo...
详细信息
Recent technological advancements in cardiovascular surgery such as transapical transcatheter aortic valve implantation (TA-TAVI) enabled treatment to elderly that were initially declined surgery. However, valve malpositioning during TA-TAVI have been reported in several cases. In this preliminary study, we present a novel approach in which a Robotically-Actuated Delivery Sheath (RADS) is used to potentially facilitate valve positioning. A model is developed that describes the shape and articulating tip position of the RADS. We developed a two-dimensional ultrasound tracking method that evaluates the tip position of the RADS in ultrasound images. Both modeling and ultrasound tracking are combined into an integrated system that facilitates closed-loop control of the articulating tip of the RADS. Experiments are performed in order to evaluate the tracking accuracy of the RADS. Experiments show mean positioning errors of approximately 2 mm along the x- and y-axes. Our study demonstrates that the RADS can potentially provide compensation for beating heart and respiratory motions during valve positioning and deployment in TA-TAVI.
In this paper, an electrodeposition method was applied to construct cell patterning structures by an alginate hydrogel. The liver cells (RLC-18) were trapped selectively within alginate structures on the micro-pattern...
详细信息
In this paper, an electrodeposition method was applied to construct cell patterning structures by an alginate hydrogel. The liver cells (RLC-18) were trapped selectively within alginate structures on the micro-patterning electrodes, which were fabricated by a photo-lithography process in circular, ring, and triangle structures. The living conditions of RLC-18 cells were confirmed until 3 days. These results indicate that biological cells were entrapped inside arbitrary shape hydrogel structures in living conditions. The fabricated 2D biological structures are important to be applied for 3D assembly of biological cells for tissue engineering applications.
There are millions of lethal land-mines that have been left in many countries after conflicts. They represent a particularly acute problem in developing countries and nations already economically hard hit by war. The ...
详细信息
In this paper, the energy stability level concept is used for examining the stable state of field robot under effects of swing motion, at some particular postures of manipulator and terrain conditions. The energy stab...
详细信息
In this paper, the energy stability level concept is used for examining the stable state of field robot under effects of swing motion, at some particular postures of manipulator and terrain conditions. The energy stability level is calculated by using the dynamic models of field robot, subject to the concept of equilibrium plane and support boundary. The results are simulated by using Matlab/Simulink for estimating the stability of field robot to supply useful predictions of stability analysis to designers and operators..
With the emergence of PCBN cutting tools, hard turning technology was used more and more widely in the difficult-to-cut materials. Therefore, it is particularly important to study the tool wear mechanism of ultrasonic...
详细信息
ISBN:
(纸本)9781479939800
With the emergence of PCBN cutting tools, hard turning technology was used more and more widely in the difficult-to-cut materials. Therefore, it is particularly important to study the tool wear mechanism of ultrasonic hard cutting and intelligent monitoring technology of tool wear. Then, a multisignal intelligent monitoring test platform of tool wear was established through Kistler9257B resistance dynamometer, the INV306DF east vibration isolation system and Japan Roy keane and high-speed microscopic photography system. The test was designed about GCr15 hardened bearing steel machined by PCBN under ultrasonic vibration and tool wear mechanism was analyzed. A special characterization and the influence of cutting conditions on tool wear are obtained under the conditions of ultrasonic cutting. Because the sensor signal information Obtained from can't be directly used to identify the tool wear state a variety of signals collected in different processing time were analyzed and disposed in this paper. And the vibration signal were analyzed by wavelet transform. Then characteristics of the tool wear state were obtained.
Energy conservation is more and more important in the iron and steel industry. We propose a method on Case-based reasoning to analyze energy consumption during the steel processes. The innovation of the proposed metho...
详细信息
In following paper control algorithms used for MIMO vibration control were presented and investigated with regard to application in modal analysis. Implementation of existing control algorithms was presented for verif...
详细信息
In following paper control algorithms used for MIMO vibration control were presented and investigated with regard to application in modal analysis. Implementation of existing control algorithms was presented for verification of its operation and development of new method combining several older methods. Objective of implementation of new method was increasing performance and quality of calculations and closer look in to development of SINE SWEEP and TIME WAVEFOR REPLICATION. Comparison of simulation and measurement data is presented in two cases of control with six degree of freedom system.
暂无评论