Electric Ducted Fan (EDF) Rocket Attitude Telemetry Using 2.4 GHz Radio Frequency

On a rocket, control requires monitoring to determine its position and attitude. Rocket stance includes roll, pitch, and yaw angles. Monitoring can be done manually without the help of tools while the object’s position is still within reach. It is difficult to carry out monitoring when the object is moving far and beyond the reach of the operator. This observation requires a monitoring system to monitor the object further. This research applies a telemetry system to a target tracking rocket. The measurement results from the IMU and GPS sensors on the rocket body will be processed by the ATMega 2560 microcontroller and sent via a 2.4 GHz RF signal. to Ground Control Station. The rocket telemetry data that has been sent to the GCS can be viewed by the operator through the GUI system in a computer program using the C# language in Visual Studio. Tests on latitude and longitude are carried out by tracking the trajectory of objects while testing for roll, pitch, and yaw angles is carried out by placing objects according to the reference angle. The results of the position obtained the values of altitude, latitude, and longitude of 0.5364 m, 0.000012°, and 0.000023°, respectively. An attitude tests for roll position, pitch, and compass heading have values of 0.35°, 0.07, and 2.90°, respectively. The telemetry data transmission distance test is still well-received at a distance of 200 with a test speed of 70 KM/hour.

Characterization of Blend PA6 +EPDM (60/40) by Tensile Tests

This paper presents a characterization of PA6 and the blend PA6+EPDM (60/40) by tensile tests in order to evaluate several mechanical properties for impact resistance applications. Results were found to be dependend on test rate (10 mm/min, 250 mm/min and 1000 mm/mm). SEM investigation point out a homogenous structure. The blend has better value of energy at break, for the higher test speed: for v=250 mm/min this characteristic has the value of energy at break 29.7 J and the blend has 76.3 J. At 1000 mm/min, PA6 has this charcateristic of 20 J, but for the blend, it is almost insensitive for the two higher test speeds (76.3 J at 250 mm/min and 72.4 J at 1000 mm/min, respectively) as compared to the neat polymer that decreases this feature when thr test spee increases. At the lowest teste speed, the values of energy at break for the materials in this study are close (90.2 J for PA6 and 87.7 J for the blend). The results from tensile tests pointed out that the formulated blend is recommended for impact resistance applications.

Effect of artificial aging on the tribological properties of an Al-25Zn-1Mg alloy

The tribological properties of aluminum based Al-25Zn-1Mg alloy was experimentally investigated in an MSc thesis, and the results are presented in this study. To this purpose, Al-25Zn-1Mg was commercially produced by casting. The prepared samples were divided into seven groups: no-process, solution treatment, and artificial aging for 1, 3, 6, 12 and 24 hours. Aged and untreated samples were subjected to tribological experiments under conditions of dry friction under 5 N and 10 N loads at speed of 200 rpm, 400 rpm and 800 rpm for a distance of 500 m. As a result of the tests, it was found that hardness increases in all samples depending on the aging process. It was also found that when the test speed was kept constant, the coefficient of friction increased with increasing load.

Application of Lightweight Convolutional Neural Network for Damage Detection of Conveyor Belt

Aiming at the problem that mining conveyor belts are easily damaged under severe working conditions, the paper proposed a deep learning-based conveyor belt damage detection method. To further explore the possibility of the application of lightweight CNNs in the detection of conveyor belt damage, the paper deeply integrates the MobileNet and Yolov4 network to achieve the lightweight of Yolov4, and performs a test on the exiting conveyor belt damage dataset containing 3000 images. The test results show that the lightweight network can effectively detect the damage of the conveyor belt, with the fastest test speed 70.26 FPS, and the highest test accuracy 93.22%. Compared with the original Yolov4, the accuracy increased by 3.5% with the speed increased by 188%. By comparing other existing detection methods, the strong generalization ability of the model is verified, which provides technical support and empirical reference for the visual monitoring and intelligent development of belt conveyors.

EVALUATION OF BLOOD OXYGEN SATURATION OF HIGH JUMPERS BASED ON ISOKINETIC TEST

ABSTRACT Introduction: An isokinetic test refers to the test of the force of a muscle or muscle group during centripetal and centrifugal movements at a constant speed in the whole range of joint motion by means of a isokinetic force tester. Objective: To explore the application of the knee centripetal flexor and extensor muscle groups in the blood oxygen saturation of high jumpers. Methods: Eighteen teenage female high jumper athletes above level 2 in a city sports school were selected. Their ages was 16.89±1.02 years old; height, 168.31±6.32cm; weight, 55.36±6.75kg. Results: At 60° S and 120° S test speed, the peak moment of the extensor muscle group on the same side of the knee was significantly greater than that of the flexor muscle group (P<0.05), while at 240° S test speed, it was the opposite. There was a significant difference in the peak moment of the flexor muscle group on the left and right side of the knee (P<0.01). Conclusions: The function of the dynamic muscle strength test system is one of the methods of studying the human muscle function. and can be used to test and evaluate the general strength of athletes. Level of evidence II; Therapeutic studies - investigation of treatment results.

Theoretical Estimation of Evaporation Heat in Paper Drying Process Based on Drying Curve

At present, the theoretical estimation of paper web’s evaporation heat is based on sorption isothermals. The measuring conditions are harsh, and the test speed is slow. This paper attempts to explore a theoretical method which can quickly determine the evaporation heat of paper web. During the new method, based on the measurement of the paper drying curve, the theoretical estimation model of paper evaporation heat was obtained by deducing the mechanism of heat and mass transfer. Compared with the traditional method based on sorption isothermals, the new model based on the drying curve has some advantages in measurement speed and easy access to basic data. Finally, the paper verifies the reliability of the model from two application scenarios of the laboratory and production line.

Technological Evaluation of High Fiber And Gluten-Free Breads Made With Teff (Eragrostis tef) and Associated Flours

Objectives This study aimed to evaluate technological parameters of high fiber and gluten-free breads made with teff (Eragrostis tef) and associated flours. Methods Four formulations were evaluated: T1, without teff (100% wheat flour- standard); T2, with 100% teff flour; T3, with 75% teff flour, 12.5% rice flour, and 12.5% cassava starch, and T4, with 50% teff flour, 25% rice flour, and 25% cassava starch. Hardness was verified using a texturometer TA.XT plus and a cylindrical probe with a 36 mm radius, by compressions performed on 12 slices of 2 cm thick and three replicates. The maximum force was determined in the first compression cycle and defined from the following conditions: cylindrical texturometer, maximum test speed of 4.0 mm/s; minimum test speed of 0.01 mm/s; rupture distance of 0.001 mm. The other rheological parameters such as: elasticity, cohesiveness, resilience, chewiness and gumminess were calculated. The results were evaluated through analysis of variance, followed by Tukey test, 5%, SPSS Statistics, version 21.0. Results The crust hardness in T1 was significantly (F = 33.09; p &lt; 0.0001) higher (188g, force) than the other samples: T2 (48 g, force), T3 (40g, force) and T4 (59g, force), which were comparable to each other. Regarding crumb hardness it was observed that T1 showed significant (F = 6.20; p &lt; 0.05) higher hardness compared to T3 (1681 g, force) and T4 (1716 g, force) and was comparable to T2 (2188g, force). The crumb elasticity was significantly (F = 27.0, p &lt; 0.0001) higher in T2 (1.10 mm), T3 (1.10 mm) and T4 (1.10 mm) compared to T1 (1.07 mm). Cohesiveness was the unique rheological parameter that it was observed to change among the breads made with teff. The crumb resilience, chewiness and gumminess were significantly higher in T1 (F = 16.31, p &lt; 0.05; F = 25.69, p &lt; 0.0001; F = 29.04, p &lt; 0.0001, respectively) than bread samples with teff. In relation to pH results it can be observed that T1 (5.8) was significantly more acid (F = 95.4, p &lt; 0.0001), than the other samples. Conclusions Teff has shown promising behavior as a new ingredient in food formulation in order to face the worldwide increasing celiac disease. The results suggest that it is possible to develop new gluten-free bakery products using teff flour without decreasing technological quality. Funding Sources We are grateful to UFRGS, CNPq and CAPES for providing scholarship to our researchers.

Mechanical Characterization of Two Blends PP+PA6+EPDM. Part 2. Results of Tensile Tests

This paper presents the values of several mechanical characteristics for two blends: H (60% PP + 12% PA6 + 8% EPDM + 20% Polybond 3200) and G (20% PP + 42% PA6 + 28% EPDM + 10% Polybond 3200) (%wt), comparing them to those of PP (polypropylene) and PA6 (polyamide 6). The adding of EPDM (ethylene propylene diene monomer rubber) and Polybond 3200 help reducing the disadvantages of simple blends made of PP+PA6, when the PA6 concentration allows for having a PA6 matrix with droplets of PP. SEM analysis helps for understanding the performance of material G as compared to the neat polymers. EDX analysis proved that there was a matrix inversion, material H having a PP matrix and material G a matrix made of PA6 with droplets of PP. Strain at break for PP and material H were proved to be insensitive to test speed, but materials G and PA6 had large value for strain at break and energy at break for v = 10 mm/min. Taking at basis the values for polyamide 6 (PA6), material G has greater values for energy at break: with 97.8% for v = 10 mm/min, with 29.5% for v= 250 mm/min and with 98% for 1000 mm/min, without exhibiting the micro and macro cavitation of PA6. This means that the recipe, the technology and the mechanical characteristics make material G a potential candidate for applications where a low and moderate impact resistant material is required.

Mechanical stress and deformation in the rotors of a high-speed PMSM and IM

High-speed electric machines are gaining importance in the field of traction drives and aviation due to their high power density. The evaluation of the mechanical stress in the rotor is one crucial part in the design process for this type of machines. The mechanical stress cannot be measured directly. Accordingly, a validation of the calculated mechanical stress is difficult and normally not performed. Instead of the mechanical stress, the deformation at the rotor surface can be measured using a spin test machine with distance sensors. The deformation can then be used to validate the calculation results.In this paper, the mechanical load exerted on an IM rotor for a $60\,\text{kW}/20000\,\frac{1}{\text{min}}$ 60 kW / 20000 1 min high-speed electric machine and an PMSM rotor for a $75~\text{kW}/25000\,\frac{1}{\text{min}}$ 75 kW / 25000 1 min high-speed electric machine is analysed in detail. The mechanical stress and the deformation are calculated and analysed using a FEM simulation model. Then, a spin test is performed on the two rotors. First, the burst speed is determined by operating two rotor samples above their defined test speed. Then, the deformation is measured at the rotor surface for different operating speeds and the defined test speed. The measurement and the simulation results are compared and discussed.It can be shown that the two designs do not exceed the maximum mechanical stress for the defined operating range. In the deformation measurement of the IM rotor, a plastic deformation up to $\varepsilon _{\text{IM, pl}} = 8$ ε IM, pl = 8 μm and elastic deformation up to $\varepsilon _{\text{IM, el}}=22$ ε IM, el = 22 μm can be seen. In regards to plastics, PMSM rotor expands up to $\varepsilon _{\text{PMSM, pl}}= 5$ ε PMSM, pl = 5 μm. The maximum elastic deformation of the PMSM rotor is $\varepsilon _{\text{PMSM, el}}=40$ ε PMSM, el = 40 μm. The comparison of the calculated and the measured elastic deformation shows good accordance for the two rotor types. Both models are capable of describing the deformation and the state of stress in the rotors. In burst tests, both rotors withstand rotational speeds far above the defined test speed.