INTEGRATING SPUR GEAR TEETH DESIGN AND ITS ANALYSIS WITH G2 PARAMETRIC BÉZIER-LIKE CUBIC TRANSITION AND SPIRAL CURVES

An involute curve (or known as an approximated curve) is mostly used in designing the gear teeth (profile) especially in spur gear. Conversely, this study has the intention to redesign the spur gear teeth using the transition (S transition and C spiral) curves (also known as the exact curves) with curvature continuity (G2) as the degree of smoothness. Method of designing the transition curves is adapted from the circle to circle templates. The applicability of the new teeth model with the chosen material, Stainless Steel Grade 304 is determined using Linear Static Analysis, Fatigue Analysis and Design Efficiency (DE). Several concepts and the related examples are shown throughout this study

G2 Bézier-Like Cubic as the S-Transition and C-Spiral Curves and Its Application in Designing a Spur Gear Tooth

Many of the researchers or designers are mostly used the involute curves (known as one of the approximation curves) to design the profile of gears. This study intends to develop the transition (S transition and C spiral) curves using Bézier–like cubic curve function with G2 (curvature) continuity as the degree of smoothness. Method of designing the transition curves is adapted by using circle to circle templates. While the transition curves are completely finished, it will be applied in redesigning the profile of spur gear. The mathematical proofs and simple models are also shown

The Development Of Planar Curves With High Aesthetic Value

Penyelidikan terhadap lengkung satah bagi menghasilkan suatu produk yang can- tik dan pengubahsuaian lengkung bagi bidang tertentu telah dibangunkan sejak tahun 70-an. Pola penyelidikan dalam bidang ini boleh dibahagikan kepada lima cabang utama iaitu pembangungan algoritma adil, pembangunan lengkung satah melalui kaedah sintesis lengkung, pembangunan algoritma baru bagi mengubahsuai lingkaran asli untuk kegua- naan reka bentuk, pengubahsuaian lengkung °eksibel (B¶ezier dan NURBS) supaya pro¯l kelengkungan adalah monoton dan akhirnya, pembangungan algoritma dalam proses pe- myuaian dan penghampiran terhadap lingkaran asli menerusi lengkung °eksibel. The research on developing planar curves to produce visually pleasing products and modifying planar curves for special purposes has been progressing since the 1970s. The pattern of research in this ¯eld of study has branched to ¯ve major groups; the devel- opment of fairing algorithms; the development of planar curves via curve synthesis, the development of algorithms to modify natural spirals to suit design intent, the modi¯cation of °exible curves (B¶ezier and NURBS) so that the curvature pro¯le is strictly monotonic and ¯nally, the development of algorithms to ¯t natural spirals and approximation via °exible curves

Optimized NURBS Curve Based G-Code Part Program for CNC Systems

Indiana University-Purdue University Indianapolis (IUPUI)Computer Numerical Control (CNC) is widely used in many industries that needs high speed machining of the parts with high precision, accuracy and good surface finish. In order to avail this the generation of the CNC part program size will be immensely big and leads to an inefficient process, which increases the delivery time and cost of products. This work presents the automation of high-accuracy CNC tool trajectory planning from CAD to G-code generation through optimal NURBs surface approximation. The proposed optimization method finds the minimum number of NURBS control points for a given admissible theoretical cord error between the desired and manufactured surfaces. The result is a compact part program that is less sensitive to data starvation than circular and spline interpolations with potential better surface finish. The proposed approach is demonstrated with the tool path generation of an involute gear profile and a topologically optimized structure is developed using this approach and then finally it is 3D printed

A Microfabricated Segmented-Involute-Foil Regenerator for Enhancing Reliability and Performance of Stirling Engines: Phase II Final Report for the Radioisotope Power Conversion Technology NRA Contract NAS3-03124

An actual-size microfabricated regenerator comprised of a stack of 42 disks, 19 mm diameter and 0.25 mm thick, with layers of microscopic, segmented, involute-shaped flow channels was fabricated and tested. The geometry resembles layers of uniformly-spaced segmented-parallel-plates, except the plates are curved. Each disk was made from electro-plated nickel using the LiGA process. This regenerator had feature sizes close to those required for an actual Stirling engine but the overall regenerator dimensions were sized for the NASA/Sunpower oscillating-flow regenerator test rig. Testing in the oscillating-flow test rig showed the regenerator performed extremely well, significantly better than currently used random-fiber material, producing the highest figures of merit ever recorded for any regenerator tested in that rig over its ~20 years of use

An extensive analysis of frequency and transient responses in S and C-shaped gears

Gears are crucial mechanical components and considerably used in consumer and industrial machinery. Gears can be grouped into five types namely spur, helical, rack and pinion, worm and bevel. Spur gear has been selected as a case model in this study mainly because it is one of the basic types of gear which can be easily constructed and fabricated. Spur gear tooth is designed using S and C-shaped transition curves. These curves are constructed using the G2 parametric Said-Ball cubic curve and clothoid templates. The result demonstrates that the C-shaped gear model which consists of the natural frequency of0.7408 Hz and low onaverage and standard deviation of 1.00E-3 mm and 8.072E-3 mm offers the most affordable displacement when compared with S-shaped and existing gear model

A Microfabricated Segmented-Involute-Foil Regenerator for Enhancing Reliability and Performance of Stirling Engines

An actual-size microfabricated regenerator comprised of a stack of 42 disks, 19 mm diameter and 0.25 mm thick, with layers of microscopic, segmented, involute-shaped flow channels was fabricated and tested. The geometry resembles layers of uniformly-spaced segmented-parallel-plates, except the plates are curved. Each disk was made from electro-plated nickel using the LiGA process. This regenerator had feature sizes close to those required for an actual Stirling engine but the overall regenerator dimensions were sized for the NASA/Sunpower oscillating-flow regenerator test rig. Testing in the oscillating-flow test rig showed the regenerator performed extremely well, significantly better than currently used random-fiber material, producing the highest figures of merit ever recorded for any regenerator tested in that rig over its approximately 20 years of use