Kinematic Displacement Analysis of a Double-Cardan-Joint Driveline

1987 ◽  
Author(s):  
I. S. Fischer ◽  
R. N. Paul
Keyword(s):  
Phase Angle ◽  
Relative Phase ◽  
Front Wheel ◽  
Constant Input ◽  
Computer Data ◽  
Output Displacement ◽  
Wheel Drive ◽  
In Series ◽  
The Difference ◽  
Cardan Joint

Abstract The input-output displacement relations of two Cardan joints arranged in series on a driveline has been investigated in detail, including the effects of unequal joints angles, the phase angle between the two Cardan joints and also such manufacturing tolerance errors as non-rigth angle link lengths and offset joint axes. A combined Newton-Raphson and Davidson-Fletcher-Powell optimization algorithm using dual-number coordinate-transformation matrices was employed to perform the analysis. An experiment was conducted to validate the results of the analysis. The apparatus consisted of a double-Cardan-joint driveline whose rotations were measured by optical shaft encoders that were sampled by a computer data-acquisition system. The equipment was arranged so that the phase angle between the joints and the offset angles between the shafts at each of the two joints could be readily varied. The “relative phase angle”, the difference between the phase angle of the two joints and the angle between the planes defined by the input and intermediate and the intermediate and output shafts, was found to be the significant factor. If the offset angles at both Cardan joints are equal, the double-Cardan-joint driveline function as a constant-velocity coupling when the magnitude of the relative phase angle is zero. If the offset angles at the two Cardan joints are unequal, a condition prevailing in the important front-wheel-drive automobile steering column, then fluctuation in output velocity for a constant input velocity is minimized although not eliminated for zero relative phase angle.

Kinematic Displacement Analysis of a Double-Cardan-Joint Driveline

1991 ◽  
Vol 113 (3) ◽  
pp. 263-271 ◽  
Author(s):  
I. S. Fischer ◽  
R. N. Paul
Keyword(s):  
Phase Angle ◽  
Relative Phase ◽  
Front Wheel ◽  
Constant Input ◽  
Computer Data ◽  
Output Displacement ◽  
Wheel Drive ◽  
In Series ◽  
The Difference ◽  
Cardan Joint

The input-output displacement relations of two Cardan joints arranged in series on a driveline has been investigated in detail, including the effects of unequal joint angles, the phase angle between the two Cardan joints and also such manufacturing tolerance errors as nonright angle moving link lengths and offset joint axes. A combined Newton-Raphson method and Davidon-Fletcher-Powell optimization algorithm using dual-number coordinate-transformation matrices was employed to perform the analysis. An experiment was conducted to validate the results of the analysis. The apparatus consisted of a double-Cardan-joint driveline whose rotations were measured by optical shaft encoders that were sampled by a computer data-acquisition system. The equipment was arranged so that the phase angle between the joints and the offset angles between the shafts at each of the two joints could be readily varied. The “relative phase angle,” the difference between the phase angle of the two joints and the angle between the planes defined by the input and intermediate and the intermediate and output shafts, was found to be the significant factor. If the offset angles at both Cardan joints are equal, the double-Cardan-joint driveline functions as a constant-velocity coupling when the magnitude of the relative phase angle is zero. If the offset angles at the two Cardan joints are unequal, a condition prevailing in the important front-wheel-drive automobile steering-column application, then fluctuation in output velocity for a constant input velocity is minimized although not eliminated for zero relative phase angle.

Slip Calculation and Analysis for Four-wheel Drive Tractors

2005 ◽  
Vol 1 (1) ◽  
pp. 7-31 ◽  
Author(s):  
Márk Szente
Keyword(s):  
Rear Wheel ◽  
Front Wheel ◽  
Wheel Slip ◽  
Wheel Load ◽  
Low Profile ◽  
Wheel Drive ◽  
The Difference ◽  
Special Respect ◽  
Four Wheel Drive ◽  
Drawbar Pull

The objective of the research of tires was to determine the dynamic rolling radius and to apply it to wheel slip calculations with special respect to vertical wheel load and to tire inflation pressure. It is typical of mechanical four-wheel drive tractors that there is a definite additional power in the tractor power chain. This additional power is dependent on the difference between the front wheel and rear wheel peripheral speeds. Further-more, the purpose was to determine the effect of additional slip on four-wheel drive tractors operated without drawbar pull. Experiments were performed on asphalt surfaces and fields. A new measurement method was developed, and a device was constructed for the implementation of three tractor wheel drive operational modes (four-wheel drive, rear-wheel drive and front-wheel drive). As the result of the experiments, a relationship was found to describe the dynamic rolling radius for low-profile radial tires tested on rigid road surfaces. On this basis, the classical slip calculation method was modified. This phenomenon appears only on hard roads and soil surfaces with high adhesion coefficients and only within the low drawbar pull range.

The Shikani HME: A New Tracheostomy Heat and Moisture Exchanger

2020 ◽  
Vol 63 (9) ◽  
pp. 2921-2929
Author(s):  
Alan H. Shikani ◽  
Elamin M. Elamin ◽  
Andrew C. Miller
Keyword(s):  
Ex Vivo ◽  
Moisture Loss ◽  
Speaking Valve ◽  
Time Zero ◽  
In Series ◽  
Turbulent Airflow ◽  
The Difference ◽  
Loss Efficiency ◽  
Heat And Moisture ◽  
Lung Simulation

Purpose Tracheostomy patients face many adversities including loss of phonation and essential airway functions including air filtering, warming, and humidification. Heat and moisture exchangers (HMEs) facilitate humidification and filtering of inspired air. The Shikani HME (S-HME) is a novel turbulent airflow HME that may be used in-line with the Shikani Speaking Valve (SSV), allowing for uniquely preserved phonation during humidification. The aims of this study were to (a) compare the airflow resistance ( R airflow ) and humidification efficiency of the S-HME and the Mallinckrodt Tracheolife II tracheostomy HME (M-HME) when dry (time zero) and wet (after 24 hr) and (b) determine if in-line application of the S-HME with a tracheostomy speaking valve significantly increases R airflow over a tracheostomy speaking valve alone (whether SSV or Passy Muir Valve [PMV]). Method A prospective observational ex vivo study was conducted using a pneumotachometer lung simulation unit to measure airflow ( Q ) amplitude and R airflow , as indicated by a pressure drop ( P Drop ) across the device (S-HME, M-HME, SSV + S-HME, and PMV). Additionally, P Drop was studied for the S-HME and M-HME when dry at time zero (T 0 ) and after 24 hr of moisture testing (T 24 ) at Q of 0.5, 1, and 1.5 L/s. Results R airflow was significantly less for the S-HME than M-HME (T 0 and T 24 ). R airflow of the SSV + S-HME in series did not significant increase R airflow over the SSV or PMV alone. Moisture loss efficiency trended toward greater efficiency for the S-HME; however, the difference was not statistically significant. Conclusions The turbulent flow S-HME provides heat and moisture exchange with similar or greater efficacy than the widely used laminar airflow M-HME, but with significantly lower resistance. The S-HME also allows the innovative advantage of in-line use with the SSV, hence allowing concurrent humidification and phonation during application, without having to manipulate either device.

Regular perturbations to the motion of a three-wheeled mobile robot with the front-wheel drive under restricted state variables*

2020 ◽  
Author(s):  
Roman Chertovskih ◽  
Anna Daryina ◽  
Askhat Diveev ◽  
Dmitry Karamzin ◽  
Fernando L. Pereira ◽  
...  
Keyword(s):  
Mobile Robot ◽  
Front Wheel ◽  
Wheeled Mobile Robot ◽  
State Variables ◽  
Wheel Drive

Mathematical models of Gauss – Kruger projection for calculation of meridians conversion on the plane and scale of the image

2018 ◽  
Vol 934 (4) ◽  
pp. 2-7
Author(s):  
P.A. Medvedev ◽  
M.V. Novgorodskaya
Keyword(s):  
Mathematical Models ◽  
Analytical Methods ◽  
Theoretical Studies ◽  
Spherical Trigonometry ◽  
Cylindrical Projection ◽  
Rectangular Coordinates ◽  
In Series ◽  
Observational Errors ◽  
The Difference

This work contains continued research carried out on improving mathematical models of the Gauss-Krueger projection in accordance with the parameters of any ellipsoid with the removal of points from the axial meridian to l ≤ 6° . In terms of formulae earlier derived by the authors with improved convergence for the calculation of planar rectangular coordinates by geodesic coordinates, the algorithms for determining the convergence of meridians on the plane and the scale of the image are obtained. The improvement of the formulae represented in the form of series in powers of the difference in longitudes was accomplished by separating spherical terms in series and then replacing their approximate sums by exact expressions using the formulae of spherical trigonometry. As in previous works published in this journal [7, 8], determining the sums of the spherical terms was carried out according to the laws of the transverse-cylindrical projection of the sphere on the plane. Theoretical studies are given and formulae are proposed for estimating the observational errors in the results of the derived algorithms. The maximum of observational errors of convergence of meridians and scale, proceeding from the specified accuracy of the determined quantities was established through analytical methods.

Synthesis and characterization of a series of 1-methyl-4-[2-aryl-1-diazenyl]piperazines and a series of ethyl 4-[2-aryl-1-diazenyl]-1-piperazinecarboxylates

2004 ◽  
Vol 82 (8) ◽  
pp. 1294-1303 ◽  
Author(s):  
Vanessa Renée Little ◽  
Keith Vaughan
Keyword(s):  
Free Energy ◽  
Chemical Shifts ◽  
Linear Free Energy Relationship ◽  
Piperazine Ring ◽  
Linear Free Energy ◽  
In Series ◽  
Methylene Groups ◽  
Diazonium Coupling ◽  
The Difference

1-Methylpiperazine was coupled with a series of diazonium salts to afford the 1-methyl-4-[2-aryl-1-diazenyl]piperazines (2), a new series of triazenes, which have been characterized by 1H and 13C NMR spectroscopy, IR spectroscopy, and elemental analysis. Assignment of the chemical shifts to specific protons and carbons in the piperazine ring was facilitated by comparison with the chemical shifts in the model compounds piperazine and 1-methylpiperazine and by a HETCOR experiment with the p-tolyl derivative (2i). A DEPT experiment with 1-methylpiperazine (6) was necessary to distinguish the methyl and methylene groups in 6, and a HETCOR spectrum of 6 enabled the correlation of proton and carbon chemical shifts. Line broadening of the signals from the ring methylene protons is attributed to restricted rotation around the N2-N3 bond of the triazene moiety in 2. The second series of triazenes, the ethyl 4-[2-phenyl-1-diazenyl]-1-piperazinecarboxylates (3), have been prepared by similar diazonium coupling to ethyl 1-piperazinecarboxylate and were similarly characterized. The chemical shifts of the piperazine ring protons are much closer together in series 3 than in series 2, resulting in distortion of the multiplets for these methylenes. It was noticed that the difference between these chemical shifts in 3 exhibited a linear free energy relationship with the Hammett substituent constants for the substituents in the aryl ring. Key words: triazene, piperazine, diazonium coupling, NMR, HETCOR, linear free energy relationship.

scholarly journals Ground maneuver for front-wheel drive aircraft via deep reinforcement learning

2021 ◽  
Author(s):  
Hao Zhang ◽  
Zongxia Jiao ◽  
Yaoxing Shang ◽  
Xiaochao Liu ◽  
Pengyuan Qi ◽  
...  
Keyword(s):  
Reinforcement Learning ◽  
Front Wheel ◽  
Wheel Drive

Design Considerations for Full-Size, Front-Wheel-Drive Vehicles

1975 ◽  
Author(s):  
Donald L. Nordeen ◽  
Richard C. Manwaring ◽  
Dennis E. Condon
Keyword(s):  
Front Wheel ◽  
Full Size ◽  
Design Considerations ◽  
Wheel Drive

Modeling of nonlinear torsional vibration of the automotive powertrain

2016 ◽  
Vol 24 (9) ◽  
pp. 1774-1786 ◽  
Author(s):  
Sérgio J Idehara ◽  
Fernando L Flach ◽  
Douglas Lemes
Keyword(s):  
Natural Frequency ◽  
Torsional Vibration ◽  
Degrees Of Freedom ◽  
Front Wheel ◽  
Torsional Stiffness ◽  
Bench Test ◽  
Passenger Car ◽  
Engine Torque ◽  
Friction Moment ◽  
Wheel Drive

A vibration model of the powertrain can be used to predict its dynamic behavior when excited by fluctuations in the engine torque and speed. The torsional vibration resulting from torque and speed fluctuations increases the rattle noise in the gearbox and it should be controlled or minimized in order to gain acceptance by clients and manufactures. The fact that the proprieties of the torsional damper integrated into the clutch disc alter the dynamic characteristic of the system is important in the automotive industry for design purposes. In this study, bench test results for the characteristics of a torsional damper for a clutch system (torsional stiffness and friction moment) and powertrain torsional vibration measurements taken in a passenger car were used to verify and calibrate the model. The adjusted model estimates the driveline natural frequency and the time response vibration. The analysis uses order tracking signal processing to isolate the response from the engine excitation (second-order). It is shown that a decrease in the stiffness of the clutch disc torsional damper lowers the natural frequency and an increase in the friction moment reduces the peak amplitude of the gearbox torsional vibration. The formulation and model adjustment showed that a nonlinear model with three degrees of freedom can represent satisfactorily the powertrain dynamics of a front-wheel drive passenger car.

Synchronization of cardiac-related discharges of sympathetic nerves with inputs from widely separated spinal segments

1995 ◽  
Vol 268 (6) ◽  
pp. R1472-R1483 ◽  
Author(s):  
G. L. Gebber ◽  
S. Zhong ◽  
S. M. Barman
Keyword(s):  
Phase Angle ◽  
Cervical Spinal Cord ◽  
Sympathetic Nerves ◽  
Time Interval ◽  
Renal Nerve ◽  
Cardiac Nerve ◽  
Spinal Segments ◽  
The Difference ◽  
Decerebrate Cats ◽  
Inferior Cardiac Nerve

We used phase spectral analysis to study the relationships between the cardiac-related discharges of pairs of postganglionic sympathetic nerves in urethan-anesthetized or decerebrate cats. Phase angle when converted to a time interval should equal the difference in conduction times from the brain to the nerves (i.e., transportation lag) if their cardiac-related discharges have a common central source. Transportation lag was estimated as the difference in the onset latencies of activation of the nerves by electrical stimulation of the medulla or cervical spinal cord. The phase angle for the cardiac-related discharges of two nerves was not always equivalent in time to the transportation lag. For example, in some cases the cardiac-related discharges of the renal nerve were coincident with or led those of the inferior cardiac nerve. In contrast, the electrically evoked responses of the renal nerve lagged those of the inferior cardiac nerve by > or = 32 ms. These observations are consistent with a model of multiple and dynamically coupled brain stem generators of the cardiac-related rhythm, each controlling a different sympathetic nerve or exerting nonuniform influences on different portions of the spinal sympathetic outflow.

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