CALIBRATION PROCEDURE AND UNCERTAINTY ANALYSIS OF AN ELECTRONIC SCALE BASED ON TWO-CURRENT SOURCE SUPPLIED CIRCUIT
Original scientific paper The article presents the prototype version of an original weight scale in which a non-conventional supplying circuit of strain gauge load cells is applied. The paper discusses construction of an electrical circuit, the way of strain gauge transducer connection and the measuring procedure. As far as the authors know, this novel electrical circuit and its application in a weight scale system have never been mentioned in literature. The specifications for directreading weight scales typically include readability, repeatability, linearity and eccentricity. The values of these parameters were estimated and used for calculation of the weight measurement uncertainty in the tested measuring range of the designed device.
Nonlinear calibration of resistance strain type electronic balance and its application in industrial sorting system
The measuring error in high precision electronic balance mainly results from the nonlinear error of weighting sensor. To deal with this problem, a novel adaptive segmenting best-fitting method is proposed in this paper to reduce the nonlinear error in the weighting sensor. A resistance strain type electronic balance manufactured by Shanghai Jing Tian Electronic Instrument Co., Ltd is used as the testing platform. The measuring results show that electronic balance can achieve the accuracy of 1 milligram within the temperature range from -10□ to 40□. And the measuring error is significantly reduced by this approach. Moreover, the improved electronic balance is applied to industrial sorting. And the design of a badminton ball head sorting system with a high sorting accuracy is accomplished and illustrated in this paper.
Influence of filler addition, storage medium and evaluation time on biaxial flexure strength and modulus of adhesive systems
Abstract Objective. This study evaluated the effects of filler addition, storage medium and time on biaxial flexural strength and flexural modulus of six adhesive systems. Materials and methods. The adhesives were either unfilled resins: Single Bond, Prime&Bond 2.1 and One-Step; or filled resins: Single Bond Plus, Prime&Bond NT and One-Step Plus. Resin discs of each product (0.5 mm thick × 6.0 mm diameter) were prepared using silicon molds (n = 10). The discs were stored dry, in water, mineral oil or ethanol for 1 week or 3 months before biaxial flexural testing. Data were statistically analyzed by 3-way ANOVA and Tukey's post-hoc test (α = 0.05). The specimens were tested in a universal testing machine at 1.27 mm/min until failure occurred. Results. In general, the storage in ethanol led to significantly lower flexural strength and flexural modulus values than the other storage conditions for all adhesives in both storage periods. Filler addition increased flexural strength and flexural modulus for Prime&Bond NT, when it was stored dry or in water for 1 week. For Single Bond Plus, the filler addition resulted in higher flexural modulus, when it was stored for 1 week in oil and in ethanol. No significant differences in flexural modulus were observed between One-Step and One-Step Plus in any storage medium. Conclusions. Results suggested that filler addition does not necessarily have to increase the flexural strength and flexural modulus. Ethanol and oil storages tended to yield opposite effects.