scholarly journals A Comparison of Low Cost Structure-borne Sound Measurement and Acceleration Measurement for Detection of Workpiece Vibrations in 5-axis Simultaneous Machining

Procedia CIRP ◽  
2013 ◽  
Vol 12 ◽  
pp. 91-96 ◽  
Author(s):  
D. Biermann ◽  
A. Zabel ◽  
T. Brüggemann ◽  
A. Barthelmey
Keyword(s):  
Low Cost ◽  
Cost Structure ◽  
Acceleration Measurement ◽  
Sound Measurement

Small Footbridges: 2 Contexts, 2 Responses

2021 ◽  
Author(s):  
Vincent Servais ◽  
Christophe Peigneux
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
Low Cost ◽  
Cost Structure ◽  
Urban Site ◽  
Weathering Steel ◽  
Fibre Reinforced Concrete ◽  
Design Technique ◽  
High Performance Fibre ◽  
Minimalist Conception

<p>This paper presents the design of two small footbridges in two different sites and economical contexts. The first footbridge, located in an urban site, is an arch made of Ultra-High-Performance Fibre-Reinforced Concrete (UHPFRC). The design technique combines the use of a contemporary material with the reappropriation of ancestral methods. The second footbridge, located in a remarkable natural site and made of weathering steel, presents both a tie-arch and truss structure. This minimalist conception leads to a “low- cost” structure.</p>

scholarly journals Viaxl: A Solution of a Low-Cost Real-Time Visual Accelerometer Based on Laser Speckle Optical Flow Detection

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7033
Author(s):  
Zhitian Li ◽  
Wuhao Yang ◽  
Xingyin Xiong ◽  
Zheng Wang ◽  
Xudong Zou
Keyword(s):  
Optical Flow ◽  
Real Time ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Laser System ◽  
Laser Speckle ◽  
Vibration Monitoring ◽  
Acceleration Measurement ◽  
Wide Range ◽  
Flow Detection

Non-contact and non-destructive acceleration measurement is receiving considerable attention due to their low cost, flexibility, and simplicity of implementation, as well as their excellent performance in some emerging applications such as medical electronics applications, vibration monitoring, and some other special scenarios. In this paper, a visual accelerometer system based on laser speckle optical flow detection named Viaxl is proposed. Compared with the conventional non-contact acceleration measurement method based on a laser system, Viaxl has moderate and stable performance with the advantages of low cost and simplicity of implementation. Experiment results demonstrate that Viaxl, which consists of a commercial camera and a low-cost laser pointer, can achieve real-time, non-contact acceleration measurement, and confirm the basic system performance of Viaxl: a measurement nonlinearity better than 1.3%, up to 31 dB signal-to-noise ratio, and 1150 Hz theoretic bandwidth; this demonstrates the huge potential of Viaxl in a wide range of applications, and provides a new possible technical method for non-contact acceleration detection.

Tensile and Shear Properties of Stitched Laminates in Hygrothermal Environment

2006 ◽  
Vol 326-328 ◽  
pp. 1753-1756
Author(s):  
Tao Huang ◽  
Gui Qiong Jiao ◽  
Ting Ting Xu
Keyword(s):  
Composite Laminates ◽  
Room Temperature ◽  
Damage Tolerance ◽  
Low Cost ◽  
Initial Crack ◽  
Cost Structure ◽  
National Standards ◽  
Temperature Environment ◽  
Fracture Appearance ◽  
Hygrothermal Environment

Stitched laminates is a low-cost structure panels with carbon fiber face sheets, and through-the-thickness Kevlar stitching. Through-the thickness stitching is proposed to increase the interlaminar strength and damage tolerance of composite laminates. Tensile and shear experiment of stitched laminates at room temperature and in hygrothermal environment was carried out according to corresponding national standards. Experiment results indicate that the tensile and shear modulus and strength were much reduced by the stitching, especially in hygrothermal environment. Micrographs of fracture appearance showed that the exist of resin-rich area is the source of crack both in normal room temperature environment and hygrothermal environment. It is concluded that hygrothermal environment and initial crack in resin-rich area were prime reason for performance lost of stitched laminates.

scholarly journals Monitoring of Cow Location in a Barn by an Open-Source, Low-Cost, Low-Energy Bluetooth Tag System

Sensors ◽  
2020 ◽  
Vol 20 (14) ◽  
pp. 3841
Author(s):  
Victor Bloch ◽  
Matti Pastell
Keyword(s):  
Open Space ◽  
Indoor Localization ◽  
Low Cost ◽  
Farm Management ◽  
Propagation Model ◽  
Low Energy ◽  
Long Distance ◽  
Acceleration Measurement ◽  
Localization Accuracy ◽  
Cost System

Indoor localization of dairy cows is important for cow behavior recognition and effective farm management. In this paper, we propose a low-cost system for low-accuracy cow localization based on the reception of signals sent by an acceleration measurement system using the Bluetooth Low Energy protocol. The system consists of low-cost tags and receiving stations. The tag specifications and the localization accuracy of the system were studied experimentally. The received signal strength propagation model and dependence on the tag orientation was studied in an open-space and a barn environment. Two experiments for the evaluation of localization accuracy were conducted with 35 and 19 cows for two days. The localization reference was achieved from feeding stations, a milking robot and videos of cows decoded manually. The localization accuracy (mean ± standard deviation) was 3.27 ± 2.11 m for the entire barn (10 × 40 m2) and 1.9 ± 0.67 m for a smaller area (4 × 5 m2). The system can be used for recognizing long-distance walking, crowded areas in the barn, e.g., queues to milking robots, and cow’s preferable locations. The estimated system cost was 500 + 20 × (cow number) € for one barn. The system has open-access software and detailed instructions for its installation and usage.

Sign in / Sign up

Export Citation Format

Share Document