A Mirror-Symmetrical XY Compliant Parallel Manipulator With Improved Performances Without Increasing the Footprint

The design of XY compliant parallel manipulators (CPMs) remains challenging considering the tradeoff between the mirror-symmetry for better constrained undesired rotations and the small footprint, although a significant number of XY CPMs have been reported in extensive applications. This paper presents a new XY CPM using mirror-symmetry without increasing its footprint, mainly aiming to reduce the undesired parasitic rotations of input and output motion stages. The concept of higher degree of stiffness centre symmetry is deployed to tackle the parasitic rotations, leading to a multi-layer compact XY CPM design with each layer being a rotation-symmetrical design. A nonlinear and analytical model of the proposed XY CPM is derived using free body diagrams and the Beam Constrained Model (BCM) to accurately analyse its performance characteristics over a large range of motion. The designed XY CPM is then verified by the nonlinear finite element analysis (FEA) method. Finally, the proposed multi-layer design is comprehensively compared with the well-received single-layer rotation-symmetrical design. It is shown in the new design that the parasitic rotations of input and output stages along with the actuator isolation are significantly reduced and that the out-of-plane-stiffness is also significantly increased.

Stability Analysis of Neighborhood Tunnels with Large Section Constructed in Steeply Jointed Rock Mass

To investigate the instability of two neighborhood tunnels with large crossing section during the construction, the Tushan subway station was taken as study background, which was built in steeply jointed rock mass. Based on the excavation method called traditional double side drift, numerical simulations of four different face excavation sequences in the two neighborhood tunnels were conducted to optimize construction sequence to improve the stability during tunneling. The results show that first excavation of the right tunnel produced less deformation of the tunnels due to joints dip. The effects of rock mass discontinuities on the stability of the tunnels were studied through comparison between the real condition with joints and the assumed condition without joints. Furthermore, six initial supporting systems with different parameters were compared, and the field observations of deformations along tunnel profile show good agreement with the numerical results. Based on the numerical simulation, the length of rock anchors could be designed asymmetrically, which is more economical than the symmetrical design. The optimized thickness of shot concrete and spacing of steel sets was 35 cm and 60 cm, respectively.

Designing and 3-D Modelling of a Sustainable Cable Stayed Bridge-A Case Study

In the world of Civil Engineering, bridges are an example of structural art expressing how much the structures have evolved till present times. The concept and design of bridges has been evolved over the past years, having numerous amounts of different geometrical models and methods to construct bridges. As the development and innovation has reached so far, the concept of bridges has made a great impact on global infrastructure by creating sustainable, effective, and aesthetical bridges around the world. development of the finest aesthetical and sustainable designs for bridges which are known as Cable Stayed BridgesThe bridge form in which the weight of the deck is supported by a number of nearly straight diagonal cables in tension running directly to one or more vertical towers. The towers transfer the cable forces to the foundations through vertical compression. The tensile forces in the cables also put the deck into horizontal compression. Cable stayed bridges are the types of bridges those are best suited for connecting wide-span crossings. Construction of cable stayed bridge is widely promoted all over the world and construction of more than 600 cable stayed bridges are recorded till date. This type of bridge is preferred over any other type due to its possible construction to the indefinite length, availability of multiple design options with the possibility of symmetrical design and excellent strength. In this paper we shall discuss numerous case studies of the cable stayed bridges, compile all the beneficial data for most of the cable stayed bridges located in India.

PERANCANGAN FILM DOKUMENTER BATIK DRUJU SEBAGAI MEDIA PENGENALAN BATIK KHAS MALANG

PERANCANGAN FILM DOKUMENTER BATIK DRUJUSEBAGAI MEDIA PENGENALAN BATIK KHAS MALANG Hindam Basith Rafiqi1721073411Penciptaan Fotografi Pascasarjana ISI YogyakartaEmail : [email protected] ABSTRAK Batik Druju berasal dari Desa Druju Kecamatan Sumbermanjing Wetan Kabupaten Malang. Batik Druju berlokasi di dusun terpencil bernama Wonorejo, di bawah perbukitan gunung kapur Malang Selatan yang membujur hingga pantai selatan Jawa. Suasana alam yang eksotis, mendorong karya batik Druju menjadi masterpiece di dunia. Ditemukan beragam motif flora, motif fauna, motif sinar matahari dan pemandangan alam yang terinspirasi dari alam sekitar desa Druju. Ciri khas warna batik Druju cenderung mengkombinasikan warna-warna kontras, banyak menggunakan unsur garis dan simetris, dan identik dengan warna hitam pekat. Proses penciptaan desain batik menggunakan bahan utama sutera dan dikerjakan dengan teknik tulis dan cap. Ciri khas batik Druju juga terlihat dari corak-corak batik yang menyambung dari bagian depan ke bagian belakang. Motif batik Druju menyambung karena ditorehkan setelah kain dijahit menjadi pakaian. Dan batik Druju juga tidak akan membuka di tempat lain dikarenakan ingin membesarkan sendiri desa mereka.Keberadaan batik Druju masih kurang populer di masyarakat khususnya Malang, hal ini menggugah penulis untuk merancang sebuah film dokumenter yang menjelaskan tentang asal usul, ciri khas motif hingga keunikan yang ada pada batik Druju.Perancangan ini dirancang dengan tujuan untuk mengenalkan asal usul batik Druju, ciri khas motif dan keunikan batik Druju, serta fungsi sosialnya kepada masyarakat sekitar yang belum banyak mengenal batik Druju. Perancangan ini menggunakan rancangan prosedural dengan menggariskan langkah-langkah yang harus diikuti dalam menghasilkan sebuah produk. Berdasarkan pengertian model diatas yaitu model yang dirancang harus dibuat dengan langkah-langkah dan bertahap. Tahapan tersebut terdiri dari tiga bagian yang lazim yaitu pra-produksi, produksi, dan pasca produksi.Perancangan ini menghasilkan film dokumenter yang merupakan salah satu media efektif untuk mengenalkan batik Druju kepada masyarakat. Diharapkan dengan adanya perancangan ini, masyarakat Indonesia bisa lebih menghargai dan ikut serta dalam melestarikan kesenian tradisional yang ada di Indonesia. Kata Kunci: Perancangan, Film dokumenter, Batik DrujuABSTRACT Batik druju originates from Druju Village, District of Sumbermanjing Wetan, Malang. Located in small village named Wonorejo, around the hill side of chalk-cliff in South Malang area that extending up till South Java beach. An exotic nature ambience, encouraging Batik Druju design to being the masterpiece in the world. We can find so many flora pattern, fauna pattern, sunshine pattern and a scenery pattern that inspired by the scenery around Druju village. The uniqueness of batik Druju can be found from their color, they usually use a contrast color with a line, symmetrical design and identic with solid black color. The process of creating batik design uses a drawing and stamp technique on a silk fabric. The other uniqueness that can be found on batik Druju was on their batik pattern that extend from the front area to back area. Batik Druju pattern connected because the drawing process was doing after the fabric was made into a clothes. Batik Druju also not open any branch out the area of Druju village, because they want to developing their village. The existence of Batik Druju was not really popular in the society, especially in Malang city, this reason encourage the author to design a documentary film that can explain about the origin, the pattern and the uniqueness which can be found in batik Druju. This design was made to introduce about the origin of batik Druju, the pattern of batik Druju and it’s social function to the society that lives around the area who didn’t know about batik Druju. This design use a procedural design with aligning the steps that have to follow for producing the product. Based on the model’s explanation, the model that was designed should divide into 3 common parts which is pre-production, production, and post-production. This design will produce a documentary film which can be an effective media to introduce about batik Druju to the society. Hopefully, with this design, the society can appreciate and accompany to preserving Indonesian traditional culture. Keywords: Designing, Documentary film, Batik Druju

Effect of Tibial Component Alignment and Posterior Slope on Tibial Coverage in a Chinese Population: A Three-dimensional Anthropometric Study

The standard for rotational alignment and posterior slope of the tibial component in total knee arthroplasty remains controversial. This study aimed to evaluate the effect of tibial component alignment and posterior slope on tibial coverage. Computer tomographic scans of 101 tibial specimens were used to reconstruct three-dimensional tibia models. A virtual surgery was performed to generate a resection plane with different posterior slopes on the proximal tibia. Symmetrical and anatomical tibial components were placed aligning to the medial one-third of tibial tubercle (Insall) and the medial edge of patella tendon (Akagi), respectively. Differences in coverage and mismatch were evaluated and statistically compared across alignments, slope angles, and genders. The tibial coverage increased from 83.21 to 85.96% for Akagi's alignments and from 85.19 to 87.22% for Insall alignments along with the increasing of posterior slope from 0 to 7 degrees. Regardless of the prosthesis design, there was a significant difference between two rotational alignments as the Insall alignment was significantly higher in tibial coverage. With a slope of 7 degrees, more overhang along with less underhang anteromedially were found in males compared with females. The current anatomical tibial design has a tendency of overhang in the anteromedial zone which does not exist in the symmetrical design. The current tibial baseplate design has better tibial coverage when aligning to the medial third of tibial tuberosity with slopes of 5 and 7 degrees. Gender difference should be taken into account and given priority for prosthesis design.