Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Aerosol Particle (1)
- Brushless DC motors (1)
- DC motors (1)
- Differential Kinematic Map (1)
- Direct-drive inverted pendulum (1)
-
- High-performance applications (1)
- Hygroscopic Fraction (1)
- Kinematics (1)
- Machine control (1)
- Magnetic saturation (1)
- Manipulator Jacobian (1)
- Motion control systems (1)
- Nonlinear control (1)
- Nonlinear control systems (1)
- Nonlinear systems (1)
- Reluctance variation (1)
- Robot Manipulators (1)
- Robots (1)
- Singularities (1)
- Smooth Manifolds (1)
- Spectra (1)
- Three-Joint Positioning Robots (1)
- Three-Joint Robots (1)
- Tracking control (1)
- Trajectory tracking control (1)
- Transformation theory (1)
Articles 1 - 7 of 7
Full-Text Articles in Aerospace Engineering
Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood
Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The relation between dry diameter (X0) and critical supersaturation (Sc) for atmospheric submicron aerosol particles is investigated using a long term air sampling program at Rolla, Missouri. The particles are passed through an electrostatic aerosol size classifier, and then through an isothermal haze chamber. Results are reported in terms of an apparent volume fraction of soluble material, εv defined such that for particles composed only of ammonium sulfate and water insoluble compounds, εv is the actual volume fraction of soluble material. The probability distribution of εv is found to be approximately Gaussian in …
Nonlinear Tracking Control Of Brushless Dc Motors For High-Performance Applications, N. Hemati, Ming-Chuan Leu
Nonlinear Tracking Control Of Brushless Dc Motors For High-Performance Applications, N. Hemati, Ming-Chuan Leu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The tracking control problem associated with brushless DC motors (BLDCMs) for high-performance applications is considered. To guarantee their high-dynamic-performance operation in motion control systems, the magnetic saturation and reluctance variation effects are accounted for in the BLDCM mathematical model. The trajectory tracking control problem is addressed in the context of the transformation theory of nonlinear systems. A nonlinear control law is implemented and shown to compensate for the nonlinearities of a BLDCM. A case study is presented in which a direct-drive inverted pendulum actuated by a BLDCM is used to investigate the effectiveness of the control law. The effectiveness of …
Generic Singularities Of Robot Manipulators, Ming-Chuan Leu, D. K. Pai
Generic Singularities Of Robot Manipulators, Ming-Chuan Leu, D. K. Pai
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The singularities of the differential kinematic map, i.e. of the manipulator Jacobian, are considered. The authors first examine the notion of a generic kinematic map, whose singularities form smooth manifolds of prescribed dimension in the joint space of the manipulator. For three-joint robots, an equivalent condition for genericity using determinants is derived. The condition lends itself to symbolic computation and is sufficient for the study of decoupled manipulators, i.e. manipulators that an be separated into a three-joint translating part and a three-joint orienting part. The results are illustrated by analyzing the singularities of two classes of three-joint positioning robots.
Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood
Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The Relation between Dry Diameter (Xo) and Critical Supersaturation (Sc) for Atmospheric Submicron Aerosol Particles is Investigated. the Particles Are Passed through an Electrostatic Aerosol Size Classifier, and Then through an Isothermal Haze Chamber. Results Are Reported in Terms of an Apparent Volume Fraction of Soluble Material, Εv, Defined Such that for Particles Composed Only of Ammonium Sulfate and Water Insoluble Compounds, Εv is the Actual Volume Fraction of Soluble Material. the Probability Distribution of Εv is Found to Be Approximately Gaussian in the Εv Range 0.2 to 1.3. the Mean Εv is 0.5, for Electrostatic Aerosol Classifier Settings of …
Axisymmetric Vibrations Of Reinforced Orthotropic Shallow Spherical Caps, Victor Birman, George J. Simitses
Axisymmetric Vibrations Of Reinforced Orthotropic Shallow Spherical Caps, Victor Birman, George J. Simitses
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Axisymmetric vibrations of reinforced shallow, spherical caps manufactured from orthotropic materials are considered. The closed form solution is obtained for the natural frequency of the cap with a clamped and immovable circular edge by assuming that the motion component parallel to the cap boundary plane (in plane) is negligible. Parametric studies are performed to assess the effect of various geometric and structural parameters on the natural frequency of the cap and, most importantly, to identify the most influencing parameters of the problem. From the generated data, it is concluded that the national frequency increases with increasing extensional stiffness and eccentricity …
Optimal Design Rules Applied To The Design Of High-Speed Mechanisms Under Deflection And Stress Constraints, Frank W. Liou, Jenny Liu
Optimal Design Rules Applied To The Design Of High-Speed Mechanisms Under Deflection And Stress Constraints, Frank W. Liou, Jenny Liu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Presented in this paper are two approaches for the design of flexible mechanisms under stress and deflection constraints. Based on the optimality conditions derived in this paper, two procedures are developed to design the minimum weight of mechanisms subject to stress and deflection limitations. The first procedure is the improvement of Thornton's design process r 17), and the second procedure is based on the interpolation technique. Several design examples are also presented to demonstrate these methods.
Adiabatic Shear Banding In Plane Strain Problems, R. C. Batra, De Shin Liu
Adiabatic Shear Banding In Plane Strain Problems, R. C. Batra, De Shin Liu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Plane strain thermomechanical deformations of a viscoplastic body are studied with the objective of analyzing the localization of deformation into narrow bands of intense straining. Two different loadings, namely, the top and bottom surfaces subjected to a prescribed tangential velocity, and these two surfaces subjected to a preassigned normal velocity, are considered. In each case a material defect, flaw, or inhomogeneity is modeled by introducing a temperature bump at the center of the specimen. The solution of the initial boundary value problem by the Galerkin-Adams method reveals that the deformation eventually localizes into a narrow band aligned along the direction …