Tracking System and Its Application in Unmanned Automobile Navigation Based on Sparse Photoelectric Sensor Network

2020 ◽  
Vol 15 (7) ◽  
pp. 799-809
Author(s):  
Yuanfei Xue
Keyword(s):  
Obstacle Avoidance ◽  
Motion Tracking ◽  
Tracking System ◽  
Control Circuit ◽  
Sensor Nodes ◽  
Infrared Sensor ◽  
Short Term ◽  
Short Term Test ◽  
Photoelectric Sensor

Sensor tracking technology has broad prospects of application in the fields of smart home and environmental protection. The passive motion tracking method of sensor networks can realize the perception of location, temperature and other information without carrying sensor nodes. A sparse network tracking system based on infrared sensor nodes is proposed in this study, which can control the running automobiles with unmanned navigation. On the basis of the theory of diffraction, the way of spreading for wireless received signal strength (RSS) can be divided into "scattered waves" and "diffracted waves," which can be regarded as two components of infrared sensing wireless signals so as to further propose the RSS indicators of "long-term testing value" and "short-term test value." Based on these indicators, a measurement model based on diffraction effects and scattering effects is proposed, and an improved particle filter algorithm is used to update the motion tracking. The hardware design of each module in an unmanned vehicle includes the main controller, tracking circuit, serial port circuit, motor control circuit and infrared sensor control circuit of the car. In the experiment, the measurement accuracy of the tracking system based on the sparse infrared photoelectric sensor was first tested. In the simulation experiment, the long-term test value, the short-term test value and the actual measurement value were compared respectively. The test results show that the theoretical RSS value and the actual test result can be matched. Moreover, the infrared photoelectric tracking system is used to design the navigation control system of unmanned cars, helping the car to drive automatically through obstacle avoidance test and tracking obstacle avoidance test.

scholarly journals Pembelajaran Kosa Kata Bahasa Arab Secara Aturan Kluster Semantik dan Aturan Kluster Bebas

2014 ◽  
Vol 67 (1) ◽  
Author(s):  
Nik Mohd Rahimi ◽  
Zahriah Hussin ◽  
Wan Normeza
Keyword(s):  
Arabic Language ◽  
The Other ◽  
Short Term ◽  
Test Analysis ◽  
Semantic Clustering ◽  
Short Term Test ◽  
Post Test ◽  
Quasi Experimental ◽  
Short And Long Term

Many Arabic language books use semantic clustering in presenting their vocabularies. However, some language experts suggest the use of semantically unrelated clustering due to a higher contribution in memorizing vocabularies among students. This study aims to investigate on which clustering has a higher contribution in memorizing vocabularies among students. The specific objectives of this study are; (a) to identify the level of students’ achievement in memorizing vocabularies using both techniques in a long-term test and a short-term test; and (b) to identify students’ achievement differences using both techniques in both tests. This study is a quasi-experimental study which using a short term and a long term post-test. This group of students was exposed to vocabularies using semantic clustering and semantically unrelated clustering. The short term post test was administered after the students were exposed with both techniques, while the long term post-test was used after seven days of the exposure. This study found that students’ achievement using semantic clustering was moderate for both tests. Meanwhile, students’ achievement using semantically unrelated clustering was very good in the short term test and good in the long term test. On the other hand, the t-test analysis showed that there are significant differences between both techniques, which students’ achievement using semantically unrelated clustering is statistically and significantly higher than students’ achievement using semantic clustering for both short and long term post-tests. Therefore, this study suggests that the semantically unrelated clustering technique needs to be used in learning Arabic vocabularies among students. 

Characterizing Suitability of Wearable Sensors for Movement Analysis Using a Programmed Robotic Motion

2013 ◽  
Author(s):  
Amanda L. Martori ◽  
Stephanie L. Carey ◽  
Redwan Alqasemi ◽  
Daniel Ashley ◽  
Rajiv V. Dubey
Keyword(s):  
Motion Tracking ◽  
Tracking System ◽  
Wearable Sensors ◽  
Robotic Arm ◽  
Joint Angles ◽  
Optical Motion ◽  
Optical Motion Tracking ◽  
Motion Tracking System ◽  
Insight Into

Wearable sensor systems have the potential to offer advancements in the study of motion disorders, particularly outside of a laboratory setting during activities of daily living or on a football field. Advantages like portability and the capability to gather real-world data have resulted in the rapid adoption of these sensors in various studies for gait analysis, balance control evaluation, physical activity recognition and fall prevention. However, before using wearable sensors in long-term acquisition studies, it is necessary to quantify and analyze errors and determine their sources. In this study, the accuracy of joint angles and velocities measured with the wearable inertial measurement unit (IMU) sensors were compared to both measurements from an optical motion-tracking system and from encoders on a robotic arm while it completed various predetermined paths. The robotic arm uses incremental encoders at each joint to measure and calculate its Cartesian motion relative to a reference frame using inverse kinematics. Motion profiles of the robotic arm were tracked using the onboard encoders, an eight-camera Vicon (Oxford, UK) motion-tracking system with passive retro-reflective markers, and four wearable IMUs by APDM (Portland, OR). In order to better isolate various types of contributing errors, linear, planar, and 3-dimensional robot motions were used. Data were collected from the sensors over several hours, which provided insight into time-based effects as well as management of large amounts of data for future long-term tracking applications. In addition, the authors have previously seen acquisition errors with high-speed gaits, thus robotic arm trajectories of varying velocities were used to provide further insight into these rate-based effects. Angular velocity and joint angles were compared for all three systems and used to investigate the hysteresis, drift and time-based effects on the IMUs as well as their accuracy during motion tracking. Effects on IMU performance due to the application of filtering algorithms were not investigated. The results show that the IMUs were able to calculate the joint angles within a clinically acceptable range of the gold standard optical motion-tracking system. The IMUs also provided accurate trajectory recognition and angular velocity measurements relative to the known motion input of the robotic arm. Future work will include the development of algorithms to detect gait abnormalities such as those seen in patients with mild traumatic brain injury (mTBI). To complement human subject testing with gait pathology, controlled introduction of gait deviations into this robotic testing framework will allow for well-characterized unit testing, providing more robust algorithm development.

scholarly journals A Long Term Shear Test for Orthotropic Composites

1993 ◽  
Vol 2 (5) ◽  
pp. 096369359300200
Author(s):  
A Yoosefinejad ◽  
P J Hogg
Keyword(s):  
Shear Test ◽  
Test Method ◽  
Test Results ◽  
Initial Test ◽  
Short Term ◽  
Shear Creep ◽  
Orthotropic Composites ◽  
Short Term Test ◽  
Properties Of Composites

A new test method is presented that is considered suitable for measuring the long term mechanical properties of composites loaded in shear. The test method is assessed for its reproducibility and accuracy and compared to conventional Iosipescu tests for short term test results. Some initial test data for long term shear creep are also presented

Methodologies for Interpretation of Short-Term Test Results which may Allow Reduction in the use of Animals in Carcinogenicity Testing

1988 ◽  
Vol 4 (2) ◽  
pp. 137-149 ◽  
Author(s):  
Fanny K. Ennever ◽  
Herbert S. Rosenkranz
Keyword(s):  
Test Results ◽  
Experimental Exposure ◽  
Short Term ◽  
Chemical Substances ◽  
Short Term Test

Assessment of the risk to humans posed by chemical substances currently relies primarily on experimental exposure of animals in lifetime feeding studies. Short-term tests for genotoxicity are much less costly and use fewer or no animals, but have not replaced the long-term animal bioassay because their results do not coincide completely. We have developed methodologies for interpretation of short-term tests which improve the usefulness of their results, and may allow them to replace the long-term animal bioassay in some circumstances.

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

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