Front and Back Movement Analysis of a Triangle-Structured Three-Wheeled Omnidirectional Mobile Robot by Varying the Angles between Two Selected Wheels

Omnidirectional robots can move in all directions without steering their wheels and it can rotate clockwise and counterclockwise with reference to their axis. In this paper, we focused only on front and back movement, to analyse the square- and triangle-structured omnidirectional robot movements. An omnidirectional mobile robot shows different performances with the different number of wheels and the omnidirectional mobile robot’s chassis design. Research is going on in this field to improve the accurate movement capability of omnidirectional mobile robots. This paper presents a design of a unique device of Angle Variable Chassis (AVC) for linear movement analysis of a three-wheeled omnidirectional mobile robot (TWOMR), at various angles (θ) between the wheels. Basic mobility algorithm is developed by varying the angles between the two selected omnidirectional wheels in TWOMR. The experiment is carried out by varying the angles (θ = 30°, 45°, 60°, 90°, and 120°) between the two selected omniwheels and analysing the movement of TWOMR in forward direction and reverse direction on a smooth cement surface. Respectively, it is compared to itself for various angles (θ), to get its advantages and weaknesses. The conclusion of the paper provides effective movement of TWOMR at a particular angle (θ) and also the application of TWOMR in different situations

Comparison of clinical features between patients with anti-synthetase syndrome and dermatomyositis: Results from the MYONET registry.

OBJECTIVES To compare clinical characteristics, including the frequency of cutaneous, extramuscular manifestations, and malignancy, between adults with anti-synthetase syndrome (ASyS) and dermatomyositis (DM). METHODS Using data regarding adults from the MYONET registry, a cohort of DM patients with anti-Mi2/-TIF1ɣ/-NXP2/-SAE/-MDA5 autoantibodies, and a cohort of ASyS patients with anti-tRNA synthetase autoantibodies (anti-Jo1/-PL7/-PL12/-OJ/-EJ/-Zo/-KS) were identified. Patients with DM sine dermatitis or with discordant dual autoantibody specificities were excluded. Sub-cohorts of patients with ASyS with or without skin involvement were defined based on presence of DM-type rashes (heliotrope rash, Gottron's papules/sign, violaceous rash, shawl sign, V sign, erythroderma, and/or periorbital rash). RESULTS In total 1,054 patients were included (DM, n = 405; ASyS, n = 649). In ASyS cohort, 31% (n = 203) had DM-type skin involvement (ASyS-DMskin). A higher frequency of extramuscular manifestations, including Mechanic's hands, Raynaud's phenomenon, arthritis, interstitial lung disease, and cardiac involvement differentiated ASyS-DMskin from DM (all p< 0.001), whereas higher frequency of any of four DM-type rashes: heliotrope rash (n = 248, 61% vs n = 90, 44%), violaceous rash (n = 166, 41% vs n = 57, 9%), V sign (n = 124, 31% vs n = 28, 4%), and shawl sign (n = 133, 33% vs n = 18, 3%) differentiated DM from ASyS-DMskin (all p< 0.005). Cancer-associated myositis (CAM) was more frequent in DM (n = 67, 17%) compared with ASyS (n = 21, 3%) and ASyS-DMskin (n = 7, 3%) cohorts (both p< 0.001). CONCLUSION DM-type rashes are frequent in patients with ASyS; however, distinct clinical manifestations differentiate these patients from classical DM. Skin involvement in ASyS does not necessitate increased malignancy surveillance. These findings will inform future ASyS classification criteria and patient management

Evolving biomass-based biogas plants: The ASTRA experience

Anaerobic digestion of animal waste in biogas plants for energy, manure and sanitation has made a significant impact in quality of rural life wherever it has been deployed. Insufficiency of animal dung resources limits the use of this technology to only an eighth of the overall Indian rural population. Yet the convenience of a biogas plant in rural households has led R&D efforts to extend the use of biogas plants to other nonanimal dung biomass feedstock and rural residues.Fermenting typical biomass residues in conventional slurry-based biogas plants has been far from successful. Most attempts to convert rural biomass residues into ‘flowable’ slurries like animal dung have rarely been successful. Alternative concepts were required. Achieving successful quasi-continuous fermentation of biomass residues has come through a break away from the ‘slurry’ fixation and animal dung digester designs of the past. A better understanding of the underlying processes has greatly helped evolve new fermentation concepts. Success has emerged only through use of multi-stage processes, where key fermentation properties of biomass feedstock have been acknowledged and digesters designed accordingly. Here, a 25-year effort in understanding the processes of biogas and biomass fermentation, developing new techniques and technologies to ferment biomass feedstock and efforts at simplifying the technology to enable sustainability carried out at the Centre for Sustainable Technologies, IISc, Bangalore is described. Finally, integration of the two or three fermentation steps into a single reactor configuration has enabled evolving simple-to-use digester designs for biomass feedstock, namely the plugflow and the solid-state stratified bed digesters

Plug Flow Digestors for Biogas Generation from Leaf Biomass

The low, family level availability of animal dung in rural Indian families restricts the spread of biogas technology. This has warranted the design and development of novel biogas plants for other biomass feedstocks. The plug-flow digestors discussed in this paper circumvent the problems associated with floating of biomass feedstocks and enable a semi-continuous operation. The long term operation of such biogas plants using a mixed green leaf biomass feedstock is reported along with its design features. Results show that during long term operation, such biogas plants have the ability to produce up to $0.5 \hspace{2mm} m^3\hspace{2mm} gas/m^3$ reactor/day (ambient conditions) at specific conversion rates ranging between 180 and 360 1 biogas/kg TS (total solids) at a 35 day retention time

High rate biomethanation using spent biomass as bacterial support

Methanogenic bacteria were found strongly adhered to several green biomass feedstocks digested in a solid-phase stratified bed (SSB) biogas fermenter, and hence these digested feedstocks were examined for their potential for use as methanogen support for a high-rate biogas fermenter, A 1.1 l experimental down flow fixed bed (DFFB) fermenter was operated at 35 degrees C using synthesized liquid waste, This gave gas production levels up to 6.5 l/l/d, Methanogenic activities measured on such biomass support material exhibited a potential to achieve much higher biogas production, Short-duration thermal and feed shocks were tolerated without their exhibiting typical methanogen washout characteristics. The DFFB fermenter functioned well even at 21 +/- 1 degrees C, with gas production rates up to 3 l/l/d, and thus appeared to have potential for producing biogas at small scales and at high rates from various combinations of liquid and solid biomass wastes

Enhanced Photoelectrochemical Response of Zn-Dotted Hematite

Photoelectrochemical response of thin films of α-Fe2O3, Zn doped α-Fe2O3, and Zn dots deposited on doped α-Fe2O3 prepared by spray pyrolysis has been studied. Samples of Zn dots were prepared using thermal evaporation method by evaporating Zn through a mesh having pore diameter of 0.7 mm. The presence of Zn-dotted islands on doped α-Fe2O3 surface exhibited significantly large photocurrent density as compared to other samples. An optimum thickness of Zn dots ∼230 Å is found to give enhanced photoresponse. The observed results are analyzed with the help of estimated values of resistivity, band gap, flatband potential, and donor density