A Low-Cost Head Supported Eye Tracker with High Precision

2013 ◽  
Vol 772 ◽  
pp. 455-460
Author(s):  
Jie Chun Chen ◽  
Shi Quan Ma ◽  
Li Ping Zhao

This paper discusses a low cost head-supported eye tracker. To measure the coordinates associated with a subjects gaze point fallen on a monitor, the subject places his head on a head support and keeps his head fixed. Meanwhile, a camera is used to capture images of the subjects left or right eye. The subjects gaze point fallen on a monitor can be determined according to the relative position of the pupil and glint in an eye image. This paper presents not only the principle of this eye tracker, but also the methods used to detect the pupil and glint in an eye image. At last, this paper presents some experimental results, and the experimental results show that the maximal average error of the experimental apparatus is 15 pixels or 0.4 in degrees.

2011 ◽  
Vol 105-107 ◽  
pp. 1951-1956
Author(s):  
Dong Qing Shen ◽  
Jian Yong Chen ◽  
Wan Cai Li ◽  
Hong Jiang ◽  
Zhen Yu Li

The purpose of a time discriminator is to decide when the input is something you are interested in. It does this by putting out a logic pulse when the input signal meets an adjustable threshold value. A low cost high performance constant fraction discriminator (CFD) for laser rangefinder using pulsed TOF (time of flight) is proposed with the accuracy been improved. The theory of CFD is deduced and discussed and a distance measuring system has been established and experimental evidence is presented to show the feasibility of solving the time walking error problem to amend the precision and improving the environmental applicability, the distance error of +/-0.5mm was observed in the lab condition. The advantages of this instrument are highlighted and the experimental results are presented.


2012 ◽  
Vol 591-593 ◽  
pp. 1231-1235 ◽  
Author(s):  
Yi Fan Zeng ◽  
Fang Fang Jiang

An error compensation method for the single pair-pole encoder has been discussed in this paper. This article analyzed offset, sensitivity error, quadrature error and ferromagnetic interference error of single-pole magnetic encoder to obtain the expression of each error. In order to facilitate error compensation, the common expression for describing the error has been summed up. The process for formatting the error can be assumed as the process of changing from circle to ellipse. Therefore the inverse of this process is the same as the process of error compensation. The experimental results show that the accuracy of magnetic encoder which used this method could reach ±1, thus the error compensation effect is obvious. The magnetic encoder which applied this method has the advantages of low-cost, high-precision and convenient to use.


2013 ◽  
Vol 748 ◽  
pp. 619-623 ◽  
Author(s):  
Yan Liang ◽  
Ye Hua Sheng ◽  
Ka Zhang

The object of this research is to reconstruct 3D dense point cloud of geographical scene. With the technology and method of computer vision , first affine invariant features are extracted and matched, then cameras parameters and 3D dense point cloud are recovered and united under geographical reference. The experimental results show that this method with low cost and high precision of centimeters can satisfy the requirements of measurement, modeling and virtual reality.


2020 ◽  
Vol 2020 (15) ◽  
pp. 350-1-350-10
Author(s):  
Yin Wang ◽  
Baekdu Choi ◽  
Davi He ◽  
Zillion Lin ◽  
George Chiu ◽  
...  

In this paper, we will introduce a novel low-cost, small size, portable nail printer. The usage of this system is to print any desired pattern on a finger nail in just a few minutes. The detailed pre-processing procedures will be described in this paper. These include image processing to find the correct printing zone, and color management to match the patterns’ color. In each phase, a novel algorithm will be introduced to refine the result. The paper will state the mathematical principles behind each phase, and show the experimental results, which illustrate the algorithms’ capabilities to handle the task.


Electronics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 741
Author(s):  
Yuseok Ban ◽  
Kyungjae Lee

Many researchers have suggested improving the retention of a user in the digital platform using a recommender system. Recent studies show that there are many potential ways to assist users to find interesting items, other than high-precision rating predictions. In this paper, we study how the diverse types of information suggested to a user can influence their behavior. The types have been divided into visual information, evaluative information, categorial information, and narrational information. Based on our experimental results, we analyze how different types of supplementary information affect the performance of a recommender in terms of encouraging users to click more items or spend more time in the digital platform.


Healthcare ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 10
Author(s):  
Chong-Bin Tsai ◽  
Wei-Yu Hung ◽  
Wei-Yen Hsu

Optokinetic nystagmus (OKN) is an involuntary eye movement induced by motion of a large proportion of the visual field. It consists of a “slow phase (SP)” with eye movements in the same direction as the movement of the pattern and a “fast phase (FP)” with saccadic eye movements in the opposite direction. Study of OKN can reveal valuable information in ophthalmology, neurology and psychology. However, the current commercially available high-resolution and research-grade eye tracker is usually expensive. Methods & Results: We developed a novel fast and effective system combined with a low-cost eye tracking device to accurately quantitatively measure OKN eye movement. Conclusions: The experimental results indicate that the proposed method achieves fast and promising results in comparisons with several traditional approaches.


2003 ◽  
Vol 474 ◽  
pp. 275-298 ◽  
Author(s):  
P. D. HOWELL ◽  
C. J. W. BREWARD

The overflowing cylinder (OFC) is an experimental apparatus designed to generate a controlled straining flow at a free surface, whose dynamic properties may then be investigated. Surfactant solution is pumped up slowly through a vertical cylinder. On reaching the top, the liquid forms a flat free surface which expands radially before over flowing down the side of the cylinder. The velocity, surface tension and surfactant concentration on the expanding free surface are measured using a variety of non-invasive techniques.A mathematical model for the OFC has been previously derived by Breward et al. (2001) and shown to give satisfactory agreement with experimental results. However, a puzzling indeterminacy in the model renders it unable to predict one scalar parameter (e.g. the surfactant concentration at the centre of the cylinder), which must be therefore be taken from the experiments.In this paper we analyse the OFC model asymptotically and numerically. We show that solutions typically develop one of two possible singularities. In the first, the surface concentration of surfactant reaches zero a finite distance from the cylinder axis, while the surface velocity tends to infinity there. In the second, the surfactant concentration is exponentially large and a stagnation point forms just inside the rim of the cylinder. We propose a criterion for selecting the free parameter, based on the elimination of both singularities, and show that it leads to good agreement with experimental results.


Sign in / Sign up

Export Citation Format

Share Document