Effect of frequency difference on sensitivity of beats perception

Two vibrations with slightly different frequencies induce the beats phenomenon. In tactile perception, when two pins of different frequencies stimulate the fingertips, an individual perceives a beats caused by a summation stimulus of the two vibrations. The present study demonstrates experimentally that humans can perceive another vibration based on the beats phenomenon when two tactile stimuli with slightly different frequencies are stimulated on the finger pad with a small contactor in different locations at the same time. Moreover, we examined the amplitude of the detection threshold to be able to perceive beats phenomenon on the index finger with 5 carrier frequency (63.1, 100, 158.5, 251.2, and 398.1 Hz) and 4 beats frequency (2.5, 3.98, 6.31, and 10 Hz) when two stimuli 1 mm distance apart are vibrated at a slightly different frequency. From the experiments, it is concluded that the amplitude threshold to be able to perceive beats decreases as the standard frequency increases under 398 Hz. Furthermore, from comparing the absolute detection threshold and beats detection threshold, as the carrier frequency increases, the required amplitude at two pins for the detection of beats decreases compared to absolute vibration

Improving Mesh Quality of Extracted Surfaces using SurfaceNets

Finite-element modelling is a standard way for simulation of soft tissue deformation. For proper modelling, triangular surface models must fulfil requirements of accuracy, smoothness, and conciseness. Several techniques proposed in the literature do not meet these requirements. In this paper we extend a new technique called SurfaceNets, which can create a globally smooth triangle mesh that retains fine detail

Using and Validating Airborne Ultrasound as a Tactile Interface within Medical Training Simulators

We have developed a system called UltraSendo that creates a force field in space using an array of ultrasonic transducers cooperatively emitting ultrasonic waves to a focal point. UltraSendo is the first application of this technology in the context of medical training simulators. A face validation study was carried out at a Catheter Laboratory in a major regional hospital

Improving Triangle Mesh Quality with SurfaceNets

Simulation of soft tissue deformation is a critical part of surgical simulation. An important method for this is finite element (FE) analysis. Models for FE analysis are typically derived by extraction of triangular surface meshes from CT or MRI image data. These meshes must fulfill requirements of accuracy, smoothness, compactness, and triangle quality. In this paper we propose new techniques for improving mesh triangle quality, based on the SurfaceNets method. Our results show that the meshes created are smooth and accurate, have good triangle quality, and fine detail is retained