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Commercially available agricultural machines are not matching with standards which affect the performances. Many times, commercially available rigid cultivator tines used in tractor drawn cultivator do not match in dimensions as given in respective BIS code. A study conducted in Udaipur, Rajasthan revealed that out of four such tines only one tine T 1 fulfilled the requirement of BIS code 7565:1975 whereas maximum deviation was observed for tine T 2 .

This article presents the kinematic analysis of the tine motion of a rotary harrow. In particular, it analyses the trajectories that the tines describe when they are pulled by the motion of the tractor and rotated by the rotors. This analysis, has led to the identification of the parameters that influence the motion of the tines and how these parameters intervene in the secondary tillage. The interaction between the tines and the soil is evaluated considering a plastic soil, i.e. without any cleavage and its propagation. With this hypothesis, the dimensions of the soil clods created by the passage of the tines in the soil have been analysed. The trajectories described by the tines of the machine, and therefore the dimensions of the portions of worked or unworked soil, are influenced by the operating parameters of the soil tillage process, such as the tractor speed and the angular speed of the tines themselves. Furthermore, a contribution is also given by the geometric parameters of the machine, such as the rotor radius and the geometric configuration of the rotary harrow in terms of rotor arrangement. This study is based on the creation of a mathematical model of the trajectories of the tines of a rotary harrow during soil tillage. The model is parametric and makes it possible to simulate and optimise the tillage process. The approach adopted also makes it possible to visualise the trajectories in graphic form for an easy visual interpretation of the results.

One of the main challenges in tribology of agricultural tools is establishing a relationship between lab-scale testing and real applications. Nevertheless, the wear micro-mechanism stands as an effective mediator amid different test scales. In this research, different scale of testing (1) in-field testing of agricultural tines (real scale), (2) intermediate test using ASTM G132 tester (macro scale/multi-asperity test) and (3) single asperity testing using scratch tester (micro-scale) were performed. A relationship was established between different scales based on the qualitative output (wear micro-mechanism) and validated using the quantitative data (degree of penetration (Dp) using 3D profiles and wear). Test variables such as particle geometry/nose radius (22 µm − 200 µm), attack angle (90°–120°) and normal force (4.5–24.2 N) were adapted to achieve various micro-mechanisms. From real scale tests, co-existing micro-mechanisms were observed, amongst which micro-cutting was the dominant mechanism responsible for material removal. Dp value 0.4 representing micro-cutting at the cutting edge contributes significantly to the reduction in service life of the tines. Dp corresponding to micro-cutting was prevalent in the intermediate test, and in the single asperity test micro-cutting was experienced with samples tested at 25 µm nose radius. The cross-sectional analysis revealed the tribo-layer formation in the test material for both real scale and multi-asperity testing. The in-situ vision observations on single asperity testing elucidate the transition in micro-mechanism. Considering the three scales of testing, it is evident that the degree of penetration, wear micro-mechanism and wear rate are in-line with each other. This novel approach in linking different scales can be extended to other abrasion prone applications such as mining, drilling, etc for material selection.

Forklifts are one of the most common types of material handling equipment used in warehouses and distribution centers. Vibration generated by forklifts may have an effect on the performance of unit loads and product damage rates. Historical research projects have focused predominantly on the measurement of vibration for over-the-road transportation. Thus, there is still a lack of understanding of the level of vibration caused by forklifts. The goal of this study was to understand how the vibration that is experienced by unit loads while being transported by forklifts is affected by factors such as speed, road condition, unit load weight, type of forklift, and sensor location. For this study, power spectral density (PSD) measurements were collected using a Lansmont Saver 9X30 data logger. Vibration levels were measured for three different industrial forklifts on two different surface types. The forklifts were driven at two different speeds while carrying two different unit load weights. For all of these conditions, the vibration levels were measured at the forklift carriage, at the back of the fork tine heel, and at the fork tine tips. The results obtained show that the highest vibrational intensity occurred at 3–4 Hz, while the highest overall Grms value observed was 0.145 G2/Hz (between 1–200 Hz). An increase in the forklift speed caused an increase in vibration intensity. In contrast, an increase in the unit load weight carried by the forklift caused a decrease in vibration intensity. Among the three forklifts studied, the gas-powered forklift had the highest vibration intensity, and all forklifts, when driven on asphalt, experienced more vibration. Published version

As leadless pacing (LP) use is expected to increase, it becomes increasingly essential that operators become familiar with the tools and techniques needed to retrieve an LP successfully. The purpose of this review is to describe a stepwise approach for the successful retrieval of tine-based LP devices, including ways to minimize complications.

During an earthquake, structures are generally excited to multiple ground motion components: two orthogonal horizontal components and one vertical component. However, the interaction of the deformations along two principal orthogonal directions in the presence of various levels of axial force in columns in post elastic range can be successfully captured if nonlinear dynamic analysis can be carried out using the bidirectional hysteresis model. On the other hand, the seismic codes prescribed simple combination rules to capture this effect in an equivalent sense even without consideration of axial force in columns. Though these rules may be valid in the elastic range, they may not be applicable in the post-elastic range as mentioned in a few seismic codes. Surprisingly, these codes did not specify any user-friendly provision needed by design offices. Hence, the applicability and efficacy of these rules in the post-elastic range is needed to be compared with that obtained from detailed nonlinear tine history analysis under orthogonal pair of bidirectional ground motions obtained from a number of chosen seismic acceleration data for performance-based design. In this study, idealized low-rise buildings with small, medium, and long periods were investigated, considering the presence of axial force in columns. Most of the current design codes and standards suggest that the addition of response of 30% of ground motion in other direction if added to the response of unidirectional ground motion in the considered direction of analysis or the resultant responses obtained by square root of sum of square from the unidirectional analyses carried out separately in both principal directions (referred as SRSS response) may predict the response with reasonable accuracy. The results obtained from the current study makes an attempt to exhibit the trends of post elastic range response for the structures. Further, it shows that seismic codes options significantly underestimate the post-elastic range seismic demand though they are proved to be adequate to predict elastic range response. This paper may prove helpful in improving code provisions.

Background Today, there is no manufacturer-supplied retrieval tool for the Micra™ pacemaker (Medtronic, Minneapolis, MN, USA); therefore, off-the-shelf catheters have been employed for retrievals. The proximal retrieval feature of the Micra™ can be snared and the device is then retracted from the myocardium, pulling the device through the tricuspid valve. This study characterizes the potential risks of Micra™ nitinol tine engagement with the tricuspid sub-valvular apparatus. Methods Fresh human hearts nonviable for transplant (n = 10) were obtained from our regional organ procurement agency (LifeSource, Minneapolis, MN, USA). Micra™ fixation tines were affixed to a linear force transducer. Tines were then engaged in tricuspid chordae tendineae to conduct a constant velocity tensile test. Each test was run until tines disengaged from the chordae tendineae or until they released from the valve apparatus. Subsequently, biomechanical failure properties of the valve apparatus and isolated chordae tendineae were determined using a series of uniaxial tensile tests. Results There were no chordal ruptures observed during our Micra™ tine extraction testing. Chordal failure required 15.0 times the force of extracting a single engaged tine, and 9.0 times the force of extracting two engaged tines. The uniaxial stresses required for isolated chordal failure averaged 17.4 N/mm2 ; failure strains exceeded 150% resting chordal length. Conclusions The forces required to rupture tricuspid chordae tendineae significantly exceeded the forces potentially imposed on the chordae during Micra™ device retrievals. We conclude that the fixation tines of the Micra™ device are unlikely to damage the tricuspid apparatus during either implant or retrieval.

To determine whether the position of the medial clamp tine during syndesmotic reduction affected reduction accuracy.Prospective cohort.Urban Level 1 trauma center.Seventy-two patients with operatively treated syndesmotic injuries.Patients underwent operative fixation of their ankle syndesmotic injuries using reduction forceps. The position of the medial clamp tine was then recorded with intraoperative fluoroscopy. Malreduction rates were then assessed with bilateral ankle computerized tomography.Fibular position within the incisura was measured with respect to the uninjured side to determine whether a malreduction had occurred. Malreductions were then analyzed for associations with injury pattern, patient demographics, and the location of the medial clamp tine.A statistically significant association was found between medial clamp position and sagittal plane syndesmosis malreduction. In reference to anterior fibular translation, there was a 0% malreduction rate in the 18 patients where the clamp tine was placed in the anterior third, a 19.4% malreduction rate in the middle third, and 60% malreduction rate in the posterior third (P = 0.006). In reference to posterior fibular translation, there was a 11.1% malreduction when clamp placement was in the anterior third, a 16.1% malreduction rate in the middle third, and 60% malreduction rate in the posterior third (P = 0.062). There were no significant associations between medial clamp position and coronal plane malreductions (overcompression or undercompression) (P = 1).When using reduction forceps for syndesmotic reduction, the position of the medial clamp tine can be highly variable. The angle created with off-axis syndesmotic clamping is likely a major culprit in iatrogenic malreduction. Sagittal plane malreduction appears to be highly sensitive to clamp obliquity, which is directly related to the medial clamp tine placement. Based on these data, we recommend placing the medial clamp tine in the anterior third of the tibial line on the lateral view to minimize malreduction risk.Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: The management of complex proximal humerus fractures (Neer’s type III, IV and fracture dislocation) is complicated. There are various treatment modalities available for proximal humerus fractures. We have designed and indigenously manufactured new plate called “SINGLE TINE PROXIMAL HUMERAL T-PLATE (3.5 mm)” for fractures of proximal humerus .The aim of this study was to examine the clinical outcome of complex proximal humeral fractures treated surgically with single tine T-plate. Materials and Methods: This is retrospective observational study included 25 patients who underwent open reduction and internal fixation with single tine T plate for proximal humerus fractures in between 2010 and 2013. . All patients were evaluated using point system of Neer’s shoulder evaluation system. Results: Mean age of the patient 47.12 years (range 22-60 years). All the fractures united with a mean duration of 14 weeks (range 10 weeks to 18 weeks). As per Neer‟s score we achieved excellent or satisfactory results in 21 out of 25 i.e. 84%. The mean Neer‟s score was 85.2 (range 64-94). We had unsatisfactory to poor result in 4 out of 25 cases (16%). (Table 1) Complications were seen in 3 cases (12%). One case of superficial wound infection and two cases of screw loosening. Conclusion: Single tine T-plate is a good alternative implant for treating complex fracture and fracture dislocation of proximal humerus .It is cost effective, and easy to use. The single tine T-plate offers good support against varus mal-reduction. Primary bone grafting is a powerful tool in managing complex fractures/ fracture-dislocation of proximal humerus.

Inferior vena cava filters are important tools used to help prevent life-threatening pulmonary embolisms in hospitalized patients with contraindications to pharmacological prophylactic anticoagulation. This is a case report of a patient who had an inferior vena cava filter placed after a traumatic subdural hematoma. He made a complete recovery but was lost to follow-up until he presented 1825 days after filter deployment with abdominal pain discovered to be from penetration of the filter tines outside the lumen and into adjacent structures. We describe a case complicated by fibrotic tine entrapment with penetration to surrounding structures and discuss the technical approach used to free and eventually remove the long-standing filter.

The goal of this article is to experimentally study how the vibrational acceleration spreads along the branch shaken by PVC tine, steel tine, and nylon tine for citrus canopy shaking harvesting and to compare the difference. PVC tine and steel tine have potential to be used as shaking rod for citrus canopy shaking harvesting. Nylon tine is a commonly used shaking rod. A tractor-mounted canopy shaker was developed to do the trial. The shaking frequency was set at 2.5 and 5 Hz. Experimental results showed that the vibrational acceleration at the shaking spot is not the highest. Spreading from shaking spot to the stem, it increases evidently. When spreading from stems of the outside subbranch to stems of the nearest inside subbranch, its average decrease percentage is 42%. The overall vibrational acceleration of shaking at 5 Hz is 1.85 times as high as shaking at 2.5 Hz. The overall vibrational acceleration exerted by straight PVC tine and steel tine is 1.77 and 1.97 times as high as that exerted by straight nylon tine, respectively. It is indicated that replacing nylon tine with steel tine or PVC tine helps remove the fruits inside the canopy. Replacing with steel tine is more effective than with PVC tine.

The objective of this work was to assess the influence of the row cleaner attack angle, the gap between discs, the working depth of a narrow tine and the strip tillage machine's working speed on tractor fuel consumption and on greenhouse effect-related CO2 gas emissions into the environment. This research was carried out by changing the row cleaner disc attack angle from 10.0° to 22.5°, the gap between discs from 105 to 135 mm, the working depth from 0 to 200 mm, and the working speed from 1.4 to 3.1 m s−1 in 44 different scenarios. The working speed of the strip tillage machine and the working depth of the narrow tine had the greatest influence on the hourly fuel consumption. The results indicate that increasing the working depth from 0 to 200 mm increases the hourly tractor fuel consumption from 10.3 to 24.3% depending on the working speed. An analysis of the experimental scenarios indicates that the lowest fuel consumption and CO2 emissions per hectare were achieved at a working speed of 2.5 m s−1. The greenhouse effect-related CO2 gas emissions were highest in scenarios with a working speed of 1.4 m s−1. CO2 emissions from tractors increased approximately 20% on average with a working depth increase from 0 to 200 mm. The attack angle of row cleaner discs 10.0°, gap between row cleaner discs 105 mm, working speed 2.5 m s−1, strip width 135 mm were the most optimal parameters for lowest fuel consumption and CO2 emissions from tractor not depending on the working depth of narrow tine.

The Discrete Elements Method has been used for several years in the simulation of agricultural tillage operations. Topics are for example the calculation of resulting tool forces, resulting furrow shapes or mixing effects. This contribution gives an example for the applicability and the quality of the results by means of current software and common model approaches. The evaluation takes place on the basis of real measurement results of a measuring tine. The validation is not only based on the total forces acting on the tool, but also on the measured load profile on the tool surface.

Mechanization of fruit and nut harvesting is becoming increasingly important because of a significant rise in the cost of manual harvesting. This work proposes a progressive analytical approach for the design and optimization of a citrus canopy shaker harvesting machine. The approach was formulated using finite element (FE) methods to find the optimum design parameters of the machine. The design parameters were defined in terms of a configuration (or stiffness) of shaking rods and two operating parameters: shaking frequency and shaking amplitude. The formulated methodology consists of determining the properties of wood, statistical modeling of the tree limbs, developing mechanistic models, and performing optimization using FE simulations. The proposed methodology employs the response surface methodology or surrogate models to quantify the objective functions, and Pareto-optimal search techniques to find the optimum designs. Three sets of machine parameters were proposed in this study to minimize tree damage and maximize fruit removal. These optimal parameters were proposed based on the configuration and distribution of limbs and fruits in a medium-size citrus tree. The optimized tine configuration of the middle and bottom section of the canopy shaker consists of a solid rod made of polyamide reinforced with 50% long glass fibers and a hollow tube made of hardened steel in a 3:1 ratio by length. These tines, when vibrating at a high frequency of 7.8 Hz and low amplitude of 3.81 to 5.08 cm (1.5 to 2 in.) and a low frequency of 3 to 3.5Â Hz and high amplitude of 13.9 to 15.2 cm (5.5 to 6 in.), provide a 25% to 30% reduction in damage to the tree limbs in the bottom and middle zones of the tree. Similarly, changes to the top sections of the canopy shaker with another set of optimized tine configurations resulted in a 40% to 45% reduction in the damage to the limbs of the top section of the tree canopy. The optimized tine configuration, thus proposed for the top section of the canopy shaker, is made of a solid rod of polyamide reinforced with 60% long glass fibers and vibrates at a frequency of 6.5 to 7.5 Hz with an amplitude of 7.6 to 8.9 cm (3 to 3.5 in.).

The paper presents research results on the effect of cutting depth and speed on the resultant force tilt angle and location of its application point on a flexible tine ended with a cultivator point. The studies were carried out in field conditions in sandy clay with the gravimetric moisture of 11.2% and volumetric density of 1470 kg·m−3. Tines whose flexibility coefficient was 0.0061; 0.0711; 0.0953 and 0.1406 m·kN−1 were used. It was found out that that the resultant force tilt angle raises at the increase of the cutting speed and drops at the increase of depth but this angle and its gradient at the increase of the cutting depth grow along with the decrease of the flexibility coefficient of tines. The increase of the cutting speed and depth causes the decrease of both the distance of the resultant force application point on the tool from the bottom of a furrow and a proportion of this parameter to the cutting depth. The courses of the distance of the resultant force application point on the tool from the bottom of a furrow and courses of proportion of this parameter to the cutting depth as the function of cutting do not differ significantly for tines with higher flexibility coefficients while for the most rigid tine values of these parameters and their gradients are higher. All obtained courses of the analysed values as a function of depth and cutting speed were described with regression equations.

Weed management is one of the tedious operations in vegetable production. Because of labor costs, time and tedium, manual weeding is unfavorable. The introduction of chemical weed control methods has alleviated these undesirable factors. However, the emergence of herbicide-resistant weeds, environmental impact and increasing demand for chemical free foods has led to investigations of alternative methods of weed control. Most implements employing mechanical cultivation cannot perform weed control close to the crops, and existing intra-row weeders have limitations. A mechanical weeding actuation system was designed, and a prototype was constructed. This actuator was developed to mechanically control intra-row weed plants. The mechanical weeding actuator consisted of a belt drive system powered by an integrated servo motor and a rotating tine weeding mechanism powered by a brushless dc motor. One of the major challenges in this project was to properly design the actuator and its weeding mechanism for effective intra-row weed control. A prototype actuator was manufactured and a series of tests was conducted to determine actuator efficacy and the corresponding force and speed requirements of the actuator. The actuator would be combined with a machine vision system for detecting crop plant locations and guiding the weeding actuator to execute mechanical weeding operations without damaging crops. In the first field experiment, the performance of the first version of the intra-row weeder was investigated across three factors: working depth, travel speed and tine mechanism rotational speed. There was evidence of differences in weed control efficacy across travel speeds. Using least square means, the slowest travel speed of 0.8 km/h had an average reduction in weed canopy area of 58.2% with standard error of 2.7% compared with the medium travel speed of 1.6 km/h with an average reduction in weed canopy area of 52.6% with standard error of 2.7%. The fastest travel speed of 2.4 km/h had an average reduction in weed canopy area of 42.4% with standard error of 2.7%.There was no statistical evidence of differences in power consumption across working depth, travel speed, or rotational speed. With increasing working depths, reduction in weed canopy area and power consumption tended to increase. With a revised version of the rotating tine weeding mechanism, a second field experiment was also conducted using three factors; tine shape, travel speed and rotational speeds. The results showed that there was no significant difference in reduction in weed canopy area across tine shapes. However, there was some indication that weed control efficacy decreased as travel speed increased. There was evidence of differences in power consumption across rotational speeds. The fastest rotation speed, 536 rpm, had a mean power consumption of 182 W and standard error of 9.4 W. The lowest rotation speed, 350 rpm, had the lowest mean power consumption of 123.5 W and a standard error of 9.4W.

Goal: The purpose of this paper was to evaluate a nitinol tine fixation design for a transcatheter pacemaker in order to determine if the tines could be easily deployed and safely removed from the myocardium, enable low, stable pacing thresholds, and minimize the potential for dislodgment. Methods: The penetration properties of 13 human hearts were compared to the deployment and fixation energy of the tines to determine if the tines could be easily deployed and removed from the myocardium. The safety factor for dislodgement was calculated by comparing the kinetic energy of the device to the fixation energy of the tines. The fixation stability was tested in 113 chronic implants across 89 animals via pacing threshold measurements or evidence of dislodgement at necropsy. Results: Based on the tine fixation and tissue energy analysis, the tines can easily penetrate the heart. The tines can be safely removed from the myocardium based on the increased tine surface area during retraction. There were no dislodgements observed in the animals and the mean pacing threshold at implant was 0.59 +/− 0.21 V and at termination was 0.65 +/− 0.36 V. The safety factor for dislodgement was determined to be 15X during simulated exercise conditions. Conclusion: The nitinol tine fixation design enabled the implant of a self-contained pacemaker within the right ventricle and was effective in meeting the design requirements. Significance: This fixation technology provides a novel solution to enable the attachment of a transcatheter pacemaker directly within the heart.

INTRODUCTI ON : Cerebellopontine angle tumors are a surgical challenge to many neurosurgeons who want to operate in this space. Although most of these tumors are benign, they are a challenge because of the complex anatomy and important neurovascular structures that traver se this space. Most common cerebellopontine angle tumor is vestibular schwannoma. The management of these cases is essentially surgical. There has been a change in the surgical strategy over the years from simple intratumoral decompression to complete micr osurgical excision, to facial nerve preservation and hearing preservation. AIMS AND OBJECTIVES: To study the clinical and radiological characteristics, know the pathological types and determine the surgical resectability and outcome of cerebellopontine ang le tumor. MATERIALS AND METHOD : It is a prospective study done in the department of Neurosurgery, King George Hospital, Visakhapatnam, Andhra Pradesh. It is a Tertiary Care Hospital. 50 patients diagnosed with cerebellopontine angle tumor were recruited in to the study and were managed. RESULTS : 50 cases of cerebellopontine angle tumors accounting for 11% of all intracranial space occupying lesions, of which vestibular schwannoma alone constituted 10%. Most of the tumors were large or giant tumors. Total resection was done in 74% of vestibular sch wannoma and 50% of meningiomas. Anatomical preservation of facial nerve was achieved in 67% of patients. CONCLUSION : C erebellopontine angle tumors show high incidence from 3 rd to 5 th decade with common symptoms being hearing loss and ataxia. Most of the pa tients presented at a delayed stage with large to giant tumors with no useful hearing. Complete excision of tumor preserving facial and lower cranial nerve function is the goal. Postoperative cerebrospinal fluid leak can be managed effectively with conserv ative therapy

We compared the displacement sensitivity between the first two symmetrical flexural resonant modes of a tuning fork crystal oscillator. An optical chopping method was employed to detect the vibrational modes of the tuning fork. Displacement sensitivities for the first two modes were extracted by applying a sinusoidal excitation voltage to the tuning fork crystal oscillator and detecting the oscillating amplitude of the focused laser beam chopped by the vibrating tine of the oscillator. We found that the ratio of the second mode sensitivity to the first one was 0.0113, in reasonable agreement with the theoretical value of 0.0131.

The experimental studies on aero thermodynamic environments of the interaction area between the wing and its baseboard (the arc board) were conducted in the arc wind tunnel. In the experiments, the angle between the fluid from the nozzle and the board- wing was 15 degrees and the coming Mach numbers were5.1 and 5.8. Some cold wall heat fluxes on the board near the wing foot and the forepart of the wing tine were measured. The results showed, for the board near the wing foot, the cold wall heat fluxes first increased and then reduced after increasing to the biggest along the flow field as the attack angle increased; For the forepart of the wing tine, the cold wall heat flux was smaller whether the attack angle increased, which meant that the down dream wing had no influence on the cold wall heat flux. Meanwhile, the cold wall fluxes on the board near the wing foot increased along with the increase of the attack angle of the board-wing. That is to say that the interaction area was more close to the wing root. In addition, the heat flux suddenly decreased and then increased when the total enthalpy was less than 6000 kJ/kg.

This paper presents a method to calculate the theoretical stress concentration factor of spatial helix gears, combined with the numerical method by ANSYS FEA package and analytic method. The formula of theoretical stress concentration factor of driving tine is fitted numerically, which suits for the general application situation. Effects of the main parameters on theoretical stress concentration factor are analyzed respectively.

Active magnetic bearing (AMB) system is a complex integrated system including mechanics, electronic and magnetism. In order to research for the basic dynamic characteristic of rotor supported by AMB, it is necessary to present mathematics method. The dynamics formula of AMB is established using theory means of dynamics of rotator and mechanics of vibrations. At the same tine, the running stability of rotor is analyzed and the example is presented in detail.

In this study, the ability of adaptive neuro-fuzzy inference system (ANFIS) and response surface methodology (RSM) approaches for predicting the draft force of subsoiling tines was assessed. Results of ANFIS and RSM approaches were compared with the results of regression models, too. The draft force was evaluated as affected by the tines at three levels (subsoiler, paraplow, and bentleg), forward speed at four levels (1.8, 2.3, 2.9 and 3.5 km/h), depth at three levels (30, 40 and 50 cm) and wing width at two levels (with wing = 30 cm and no-wing = 0 cm) at four replications. Test results show that tine types, speed, depth, and wing width were significant on the draft force but quadruplet interaction effect of them. Moreover, the increment of forwarding speed, tillage depth and adding wing increased the draft force of all tine types. Field data were applied for the development of the regression, ANFIS and RSM models. The results of ANFIS part showed that Gaussian membership function (gaussmf) configuration was found to denote MSE of 0.0156 and R 2 of 0.998, consequently, it was the best ANFIS model. The RSM and best regression models had a high correlation (R 2 = 0.9927 and 0.9968, respectively), too while ANFIS model was the better than them to predict the draft force of subsoiling tines with higher accuracy. The RSM graphs showed the changes of the output variable (draft force) caused by changes of input variables (tine type, speed, depth and wing width) better than ANFIS graphs for their surfaces with higher pixels. Moreover, the optimization process for prediction of the draft force was obtained 4.22 kN for depth of 35.19 cm, the forward speed of 1.9 km/h and wing width of 26.97 cm using the RSM approach.

At present, the efficiency of the automatic foam extinguishing systems is less than 60% due to the low expansion rate of the produced foam. In order to solve this problem the influence of the geometric parameters of the sprinkler frame arm and deflector on the foam expansion rate was studied. A collapsible sprinkler design with the ability to replace its elements was developed to reduce the cost of the research. For the manufacture of elements of such sprinkler the optimal 3D printing technological parameters (FDM) were determined in order to provide the necessary strength and stiffness of the design. The obtained experimental dependences of the foam expansion rate on the frame arm length, the outer deflector diameter, the inner deflector diameter, the deflector tine spacing angle, the deflector ledges height and the deflector taper angle are also presented in the article. Moreover, the model for predicting the foam expansion rate values depending on the geometrical parameters of the sprinkler was developed. Using the «Desirability profiles » module in STATISTICA the sprinkler design was optimized to produce the foam with the highest expansion rate value.

In this paper, a new type of skew gear mechanism named as space curve meshing skew gear mechanism (SCMSGM) is proposed. Fundamental design equations are deduced for SCMSGM with an arbitrary alternate angle within 0°–180°. Space curve meshing equations of SCMSGM are established firstly. Then the equations of the driving contact curve and driven contact curve are deduced. And the equations of the driving tine center curve and driven tine center curve are subsequently derived. According to these fundamental design equations, an example is illustrated in detail and simulated in Pro/E software. The prototype samples with a 135° alternate angle were fabricated of 316L stainless steel by selective laser melting technology and an experiment was carried out to test their kinematic performance. The experimental result shows that the SCMSGM designed by the deduced fundamental equations in this paper is capable of committing a transmission with a precise transmission ratio between two skew axes at an arbitrary alternate angle.

We present an optical detection method for the fundamental vibrational mode of a tuning fork crystal oscillator in air. A focused He/ Ne laser beam is directed onto the edge of one vibrating tine of the tuning fork; its vibrating motion chops the incoming laser beam and modulates the intensity. The beam with modulated intensity is then detected and converted to an electrical signal by a high-speed photo-detector. This electrical signal is a sinusoid at the resonant frequency of the tuning fork vibration, which is 32.76 kHz. Our scheme is robust enough that the sinusoidal signal is detectable at up to 40° of rotation of the tuning fork.

The micro-irrigation flow regulator markedly improved the uniformity of micro-irrigation systems by adjusting flow with internal elastomers. Meanwhile, the relatively wide flow path and the ability to self-clean ensure the high anti-clogging performance of the regulators and reduce clogging risk in the irrigation system. Hence the ability to work under various pressures or poor water supply conditions became the advantage of the micro-irrigation flow regulator. In this paper, a large eddy simulation (LES) model was established to simulate the fluid–structure interaction (FSI) of micro-irrigation flow regulators, and its feasibility was proven through a hydraulic performance experiment. The internal flow fields and elastomers were then studied and optimized by adopting this model. The results showed that for the internal elastomer, maximal displacement of the elastic diaphragm occurred in the centre of the circle. When the elastic diaphragm thickness or elastic modulus decreased, the flow regime indexes declined as a whole. Such a decrement indicated performance improvement of the flow regulators. But when both the thickness and elastic modulus of elastic diaphragm reach their minimums (0.3 mm and 3.0 MPa), the diaphragm itself started to oscillate, or drop dramatically in area of flow cross-section, due to oversized deformation, resulting in deterioration of irrigation uniformity. As for the flow path, its energy dissipation effect was significantly improved by adopting the fractal flow path for optimization.Finally, a new micro-irrigation flow regulator (tooth tine angle of fractal flow path: 60°, thickness of elastomer: 0.3 mm, elastic modulus of elastomer: 3.5 MPa) was designed, and its flow regime index was reduced to 0.08, representing a good and steady performance in flow regulation. Copyright © 2013 John Wiley & Sons, Ltd.

This paper presents two models for predicting the frequency response of micro-scale oscillatory probes. These probes are manufactured by attaching a thin fiber to the free end of one tine of a quartz tuning fork oscillator. In these studies, the attached fibers were either 75 μm diameter tungsten or 7 μm diameter carbon with lengths ranging from around 1 to 15 mm. The oscillators used in these studies were commercial 32.7 kHz quartz tuning forks. The first theoretical model considers lateral vibration of two beams serially connected and provides a characteristic equation from which the roots (eigenvalues) are extracted to determine the natural frequencies of the probe. A second, lumped model approximation is used to derive an approximate frequency response function for prediction of tine displacements as a function of a modal force excitation corresponding to the first mode of the tine in the absence of a fiber. These models are used to evaluate the effect of changes in both length and diameter of the attached fibers. Theoretical values of the natural frequencies of different modes show an asymptotic relationship with the length and a linear relationship with the diameter of the attached fiber. Similar results are observed from experiment, one with a tungsten probe having an initial fiber length of 14.11 mm incrementally etched down to 0.83 mm, and another tungsten probe of length 8.16 mm incrementally etched in diameter, in both cases using chronocoulometry to determine incremental volumetric material removal. The lumped model is used to provide a frequency response again reveals poles and zeros that are consistent with experimental measurements. Finite element analysis shows mode shapes similar to experimental microscope observations of the resonating carbon probes. This model provides a means of interpreting measured responses in terms of the relative motion of the tine and attached fibers. Of particular relevance is that, when a “zero” is observed in the response of the tine, one mode of the fiber is matched to the tine frequency and is acting as an absorber. This represents an optimal condition for contact sensing and for transferring energy to the fiber for fluid mixing, touch sensing, and surface modification applications.

In some recent papers a new gear mechanism named Space-Curve Meshing-Wheel (SCMW) has been proposed by the present authors. However the research there presented was limited in the equal tine radius case. This paper presents a method to solve the SCMW design with unequal tine radii. As a consequence, with a pair of contact curves, the tine radii of the driving and driven wheels can be selected independently according to actual need. A design example is illustrated in detail and testified in both simulation and practical experiment. This method provides a design fundamental for the SCMWs to optimize the tine shapes according to strength conditions, and therefore it can extend their application in industrial.

In this study, equations of the maximum bending stress (MBS) on the root of driving tine of the space-curve meshing-wheel (SCMW) are deduced. Four factors have an impact on stress concentration of the driving tines, the helix angle, the fillet, the diameter of driving tines and the radius of the spiral curve for driving tine. They have been studied by Finite Element Method (FEM). Results show the former two factors have great impact on stress concentration while the last two could be ignored. Then the method to gain the stress concentration factor is proposed. It makes the theoretical result of the MBS on the root of driving tine match the actual result.

Mechanical harvesting is increasingly being employed in the citrus industry of Florida because of the faster and efficient harvesting it provides with comparatively lower cost when compared to manual harvesting. Continuous canopy shakers are the only mechanical harvesters commercially used in Florida. The main concerns regarding the use of these machines are damage to tree and detrimental effect on next year yield. Because of these concerns, only a very low percentage (6-7%) of the acreage is being harvested mechanically. To improve these machines and address the growers' concerns, experiments were conducted to study the force and acceleration distribution on the tree branches and fruits. The acceleration was measured at different locations in the canopy using tri-axis accelerometers attached to the branch and data was recorded using ZigBee^(R) transceivers. The distribution of force and acceleration along an individual branch in trees of two different sizes were studied at three different tine angles and frequencies of the shaker. Both distributions were modeled using the Curve Fitting Toolbox(TM) of Matlab^(R). The results suggested that the force was higher for the fruits inside the canopy than the ones at the edges. It was also observed that the maximum force required to remove the fruit mechanically was only 18% of the traditionally measured fruit detachment force. The force along the branch was found to be Gaussian in nature and the acceleration along the branch was found to be exponential.

A two-tine oscillatory subsoiler was developed at the University of South Australia for fracturing the compacted soil layers between grapevines using small tractors. As the soil forces exerted on the tines were unbalanced, the tillage forces, torque peaks through the power-take-off and the inertia of the tines transferred vibrations to the tractor and its driver. These vibrations currently prevent the commercial use of soil loosening settings that require the lowest engine power to be used.A simulation model is presented that calculates the dynamic behaviour of the tractor oscillating subsoiler system with the focus being on the vibrations at the tractor driver’s seat. The model considers the three oscillatory tillage phases of soil cutting, backing-off and catching-up, with positive and negative oscillation angles; tine inertia and the various tyre stiffness and damping parameters.The results of the simulation were compared to field measurements and a good correlation of both the magnitude of root mean square (RMS) acceleration and the response to change in the oscillatory tillage parameters of amplitude, frequency and oscillation angle were obtained. Refereed/Peer-reviewed

This paper presents a manipulation system consisting of a coarse/fine XY positioning system and an out-of-plane manipulator. The object of the system is to conduct tine positioning and manipulation of micro parts. The fine stage and the out-of-plane manipulator have compliant mechanisms with flexure hinges, which are driven by stack-type piezoelectric elements. In the fine stage, the compliant mechanism plays the roles of motion guide and displacement amplification. The out-of-plane manipulator contains three piezo-driven compliant mechanisms for large working range and fine resolution. For large displacement, the compliant mechanism is implemented by a two-step displacement amplification mechanism. The compliant mechanisms are manufactured by wire electro-discharge machining for flexure hinges. Experiments demonstrate that the developed system is applicable to a fine positioning and fine manipulation of micro parts.

Injection of animal slurry into the soil for a growing crop can reduce the impact on the environment and the surroundings. However, yield can be adversely affected due to crop damage caused by the injection operation. This study focused on developing and testing tines for injecting the liquid fraction of separated slurry into soil. The aim was to design a shallow tine combining soil opening and pressurized injection. The analysis focuses on draft force requirements. Three pressurized injection tines with nozzles pointing forward, downward, and rearward were developed for injecting separated slurry into soil for growing crops. The horizontal and vertical force requirements for each of the nozzle configurations were measured. Using pressurized injection with jets pointing rearward reduced the horizontal draft force by approximately 20% compared to operating the tine without jets. The energy saved for driving the tine is more than counterbalanced by the increased energy consumption to build up the pressure in the tine. However, this extra energy has to be delivered through the tractor power take-off, which in some cases can be a more effective means of energy transfer than the driving wheels.

A deep working oscillatory subsoiler was developed at the University of South Australia to be towed by a tractor (3 t and 70 kW) in a semi-mounted configuration. During use, the soil-tool interaction forces transferred too much vibration to the tractor when operating at the desired subsoiler settings. In order to reduce the tractor vibrations, the source of vibration was studied using the power spectral density method to correlate the tractor seat vibrations to machine operating parameters. It was found that tyre lug engagement and the engine speed did not have significant effect on tractor vibration. The soil-tool interaction of both soil cutting and compaction during the oscillating motion of the tine, combined with the torque peaks on the driveline from the power take-off to the tines, had the dominant effect on vibration.

Taguchi' design of experiment method and statistical F-test were used to optimize design of tuning forks for use in Qualcomm® mobile station modem (MSM)-3000TM series central processing unit chips of code division multiple access, personal communication system, and global system for mobile communication systems. Design parameters for motional capacitance C1 was further optimized after much trial and error so that as-fabricated resonance frequency values of a tuning fork blank remain almost the same prior to final frequency adjustment plating of the mounted crystals, regardless of packaging pressure change from ambient to designated 6 × 10– 5 Torr. Finite element method modeling was used in conjunction with Taguchi' design of experiment method and, after much trial and error, this enabled selection of essential design parameters to effectively manufacture tuning fork test samples using photolithography with subsequent photoresist spray coating. The tuning fork test samples thus fabricated were characterized and analyzed using Taguchi' method and statistical F-test to evaluate sensitivity of motional capacitance C1 and as-fabricated resonance frequency for various design parameters at ambient to designated packaging pressure of 6 × 10– 5 Torr. Motional capacitance C1 is most sensitive to tine width and tine surface electrode width. Unlike as-fabricated resonance frequency values, motional capacitance values do change with vacuum level of the package. However, tine width asymmetry, electrode thickness and tine tip electrode thickness could be freely adjusted for crystal impedance level without affecting resonance frequency and motional capacitance value. Other design parameters could be adjusted to best suit the manufacturing process.

This paper carried on mechanics analysis and the research to the Curved Rake Tine Frame and Headstock of film recycling machine which could cut cotton stalk and recycle the used film simultaneously. This machine was developed by the Institute of Agriculture Machine Xingjiang Academy of Agricultural Sciences. This paper used servile methods to identify the structural deficiencies such as Visualization Virtual Design, Finite Element Method and Testing Method. These data provided a theoretical basis for the design of the Curved Rake Tine Frame and Headstock.

This paper presents a finite element (FE) brush modelling study with respect to facilitating automation of road sweeping process. Achieving efficient road sweeping was difficult in the past, partly because the fundamental characteristics of sweeping brushes were not known. This study uses a FE model to analyze the deformation of metal-tine sweeping brushes as they are compressed and rotated on the road. The brush tines are regarded as slender cantilever beams and modelled by commercial FE software package ANSYS. Using this model, some important brush characteristics such as force-deformation relationship, contact pattern, and rotational torque have been obtained. The effect of different tine geometry on the brush characteristics has also been analyzed using this model.

We describe Lamello, an approach for creating tangible in- put components that recognize user interaction via passive acoustic sensing. Lamello employs comb-like structures with varying-length tines at interaction points (e.g., along slider paths). Moving a component generates tine strikes; a real- time audio processing pipeline analyzes the resultant sounds and emits high-level interaction events. Our main contributions are in the co-design of the tine structures, information encoding schemes, and audio analysis. We demonstrate 3D printed Lamello-powered buttons, sliders, and dials.

An investigation was carried out to predict the draught requirements of commonly used tillage implements in any field condition from the knowledge of : (i) the draught requirements of reference tillage tools in a reference soil condition; and (ii) the scale factors related to soil properties and implement geometry. In the first step, the draught requirements of three different reference tillage tools: (1) a plough with a width of cut of 0·1 m; (2) a tine with a width of cut of 0·075 m and (3) a disc with a diameter of 0·3 m were verified in the soil bin by operating in a reference soil condition (sandy clay loam soil with average cone penetration resistance of 472 kPa and bulk density of 1170±20 kg/m3) at three depths (0·05, 0·075 and 0·1 m) and four speeds (1·2, 2·2, 3·2 and 4·2 km/h). In the second step, the draught requirements of six different scale-model implements: two mouldboard ploughs (0·15 and 0·25 m width); two cultivators (2 and 3 tine); and two disc gangs (0·34 and 0·37 m width) were measured in the same soil with five different soil conditions (average cone penetration resistance and the corresponding bulk density varied from 470 to 1420 kPa and 1170 to 1680 kg/m3, respectively) at particular depth (0·075 m) and speed of operation (3·2 km/h). The empirical equations for draught requirements of reference tillage tools and hence, scale-model implements were developed using orthogonal and multiple regression techniques. The developed empirical equations were verified in the laboratory as well as in the field conditions. A good general agreement between observed and predicted draught values was found with the average absolute variations of 7·0%, 6·2% and 7·5% in the laboratory as compared to 10·6%, 10·2% and 13·2% in the field for the mouldboard plough, cultivator and offset disc harrow respectively. This methodology produced sufficiently accurate results to enable the draught prediction of tillage implements in different soil conditions by testing only the reference tillage tool in the desired soil type at reference soil condition.

There are many models describing the work of rotary tillers, including torque evaluation. However, the work of a rotary subsoiler is different from that of a rotary tiller, which cuts the soil into pieces and throws them behind the machine. The rotary subsoiler acts on the soil with pressure similar to passive narrow tines. However, the existing models of forces acting on passive implements refer only to their linear movement. In this paper, a hypothesis has been made that the methods used in predicting the forces on soil cutting narrow tines may be applied to a rotary subsoiler, taking into consideration the subsequent positions of the working element in soil and including some corrections connected to the rotary movement of such a tine. On this basis a new mathematical model for predicting torque for a rotary subsoiler in different soils has been developed. Because no theoretical models describing the work of rotary subsoilers can be found, the prediction of the torque requirement may be very important for designers, as well as for other experts applying such machines in the field operations. After development the model was verified in experiments performed in a soil bin, which proved the model to be reliable.

We investigated the dissociation of polyethylene liner from the Harris-Galante II metal shell inarthritis patients with rheumatoid arthritis. A total of 41 total hip arthroplasties using Harris-Galante II cup in 34 patients were reviewed retrospectively. There were three cases with dissociation of the polyethylene liner and locking tine breakage of metal shell, and one case with locking tine breakage without dissociation of the polyethylene liner. In three cases with dissociation of the polyethylene liner, two cups had been placed relatively horizontally while the third had been placed relatively vertically. In general, high activity, heavy body weight, and young age are thought to be risk factors for polyethylene liner dissociation, but these patients generally have lower activity and lighter body weight compared to patients with osteoarthritis or avascular necrosis of the femoral head. The use of small femoral heads and either horizontal or vertical cup placement may have allowed impingement and tine damage, contributing to liner dissociation in these relatively inactive patients.

Understanding the mechanical actions of weeding with a spring-tine harrow at different tine settings is necessary to achieve optimal weed control. The mechanical actions of a tine harrow in two different soils at two different locations on the harrow were investigated, pointing out the effects of varied implement settings and operational conditions on the tine weeding performance. A commercially available flexible harrow tine was investigated in sandy and sandy clay loam soils. The tine was pulled in soil bins without plants in order to avoid biological variances. Tine movements and forces acting on the tine were measured with strain gauges and analysed as the mean backward and upward tine torsion, the variation of the tine location around the mean position in sideward and upward direction and the properties of the vibrational frequency in sideward and upward direction during working. In addition, a high-speed camera was used to provide visible description of tine mechanical actions. Results showed that different tine settings and operational conditions and their interaction with soil type and tine location have different responses on certain weeding and tine parameters. High selectivity requires minimising the tine upward and lateral movements, preserving a constant penetration depth and a constant distance from crops. This could be ensured by a low speed, a thin tine and a trailing or vertical tine orientation for a constant depth and trailing or leading tine orientation for constant distance from crops. However, effective weed uprooting would require a high speed, a deep penetration, standard thick tine and a leading tine orientation. As the high selectivity and high effectivity requirement need different tine settings, optimisation of the weed harrow depends on intended effects.

Resonance frequency of a quartz tuning fork crystal for use in chips of code division multiple access, personal communication system, and a global system for mobile communication was comprehensively analyzed by an analytical method, Sezawa's approximations and the finite element method. A comparison was also made in a more detailed and comprehensive manner among resonance frequencies calculated by the Sezawa's approximations. From the finite element method analysis results, actual tuning fork crystals were fabricated using mass-production capable positive (subtractive) photolithography, selective etching and subsequent positive (subtractive) photoresist spray coating method. A target resonance frequency of 32.768 kHz + 544 Hz was aimed at and a general scheme of commercially available 32.768 kHz tuning fork resonators was also followed in designing tuning fork geometry, tine electrode pattern and thickness. Comprehensive comparison was made among the modeled and experimentally measured resonance frequencies and the discrepancy explained and discussed. Finite element method analysis results quite closely agreed with the experimentally measured resonance frequencies (32.676–32.933 kHz) of the fabricated tuning fork samples measured at a vacuum level of 10 −5 Torr. The difference between modeling and experimentally measured resonance frequency is attributed to the error in exactly manufacturing tuning fork tine width by photolithography. However, the tuning fork design using finite element method modeling must be modified comprehensively to optimize various design parameters affecting both the resonance frequency and other crystal parameters, most importantly crystal impedance (series resistance).