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The increase in environmental consciousness and waste-to-wealth concepts in the automobile sector has led to the use of natural fibers in desirable quantities. The current study deals with the extraction, treatment, and utilization of Lycium ferocissimum stem fibers for friction composite in braking applications. The fibers of Lycium ferocissimum were extracted through manual retting and subsequently treated with benzoyl chloride. Both the benzoyl chloride treated and untreated fibers of Lycium ferocissimum were employed as reinforcements in the formulation of a friction composite, following the standard practices of the industry, and the comparison was made using commercially available friction composite. The developed friction composites were tested for original equipment manufacturer quality requirements following industrial Standards. The friction composite’s tribological behavior was analyzed using the Chase test following the Society of Automotive Engineers standards. The worn surface characteristics were analyzed using scanning electron microscope. The test results elucidated that benzoyl chloride-treated Lycium ferocissimum fibers-based friction composites showed good frictional properties with better wear resistance compared to others, having a weight loss of 5.4%.

In recent decades, the production of natural fiber composites has increased due to their biodegradability and lower costs. In the current work, Vachellia farnesiana fibers were selected and extracted by the manual retting process. The obtained Vachellia farnesiana fibers were chemically treated with hydrochloric acid (HCl) and sodium hydroxide (NaOH) solutions. The chemically treated and untreated Vachellia farnesiana fibers were characterized for physical, chemical, tensile, morphological, and thermal properties. Test results showed that the cellulose content was 47.8 ± 0.697 weight % for NaOH treated Vachellia farnesiana fibers with reduced moisture and amorphous contents. HCl treated Vachellia farnesiana fiber showed more cellulose content removal, which resulted in degradation of its properties due to the acidic nature of HCl.

The application suitability of natural fibers is increased by the method of hybridization. The current study deals with the development and characterization of four different tri-layer composites by varying the stacking sequence of Parthenium hysterophorus and Impomea pes-caprae fibers with epoxy as a matrix, by using the conventional hand layup process. The mechanical properties, namely tensile, flexural, impact, Shore D hardness, and water absorption properties, were analyzed as per ASTM. The test results show that composites with upper layers of Impomea pes-caprae and a core layer of Parthenium hysterophorus fibers showed enhanced mechanical properties and reduced water absorption, thereby proving its suitability for lightweight medium load applications. Morphological studies using Scanning Electron Microscope elucidated the fiber bonding and void characteristics of the tested composites.

The current study deals with the extraction and characterization of natural cellulose fibers from Lycium ferocissimum plant stems. The fibers were retted using a manual retting process and were subjected to benzoylation treatment. The properties namely physio-chemical, thermal, crystalline, and morphological were measured for both untreated and chemical treated Lycium ferocissimum fibers. Then, the epoxy composites were fabricated using chemical treated and untreated Lycium ferocissimum fibers and analyzed for their mechanical performance. The cellulose content was 67.19%, with the crystalline index of 47.7% for the benzoyl chloride treated Lycium ferocissimum fibers, which were substantially higher than untreated Lycium ferocissimum fibers. While the epoxy composites containing benzoyl chloride treated Lycium ferocissimum fibers showed an increase in the ultimate flexural strength of 51.3 MPa, while it was 42 MPa for untreated Lycium ferocissimum fiber-based composite. Thus, the test results elucidated that benzoyl chloride treatment reduced Lycium ferocissimum fibers hydrophilicity that induced fiber wettability with the matrix to better mechanical properties compared to untreated Lycium ferocissimum fiber-based composites.

The need for eco-friendly materials has risen globally due to environmental consciousness. This work involved the extraction and utilization of silane treated and untreated Citrullus lanatus stem fiber for eco-friendly brake friction composites. The fibers were extracted from Citrullus lanatus plant stems using a conventional manual retting process followed by silane treatment. The silane-treated and untreated Citrullus lanatus stem fibers were analyzed for physical, chemical, and thermal characteristics. The application suitability was explored by developing brake friction composites in the form of brake pads using silane-treated and untreated Citrullus lanatus stem fiber in addition to parental ingredients by the conventional process and compared with the glass fiber-based one. The developed brake pads were analyzed for performance properties as per industrial standards. The tribological performance was measured using the Chase test following IS2742-Part-4. The test results showed that cellulose content was 60.3% for silane-treated Citrullus lanatus fibers while it was 53.7% for untreated Citrullus lanatus fibers. The normal friction properties showed that silane-treated Citrullus lanatus stem fibers-based brake pads had 0.413 while it was 0.41 for glass fiber-based brake pads and 0.392 for untreated fiber-based ones. Using a scanning electron microscope, the worn surface of Chase brake pads revealed features like plowing, plateau formations.

By hybridizing fibers, natural fibers are widely employed to substitute synthetic fibers in all feasible applications. The present study focuses on the development and characterization of hybrid Areca-Pineapple fiber epoxy composites with varied stacking sequences. Using the hand lay-up method, four types of stacking sequence-based epoxy composites were developed. ASTM standards were used to evaluate the mechanical and water absorption characteristics of the developed composites. Test results revealed that the ultimate tensile (53.433 MPa), flexural (60 MPa), compression (16.591 MPa), and Shore-D hardness (91) values were higher for three layers of pineapple fibers-based epoxy composites. At the same time, the three layers of areca fibers-based epoxy composites showed better impact (0.8 J) and water absorption properties (2.4%) due to the high amorphous contents of the fibers. Morphological studies carried out by a scanning-electron-microscope revealed stronger fiber-matrix bonding, resulting in higher mechanical test results.

Recently, bio-based composites are the prominent material to replace several synthetic fiber-based composites because of their abundant availability, ecological, biodegradable, and sustainable properties. This study aims to examine the use of new natural fibers, which were extracted from the Momordica charantia plant stem as reinforcement in polymer composites. The results showed that the Momordica charantia fibers had cellulose content (61.2 %), density (1339 ± 6.4 kg/m3), fiber diameter (198 ± 3.9 µm). The thermal studies using thermogravimetric analysis revealed the degradation temperature as 339.1°C with a char residue of 21% at 600°C. The results of this work confirmed that the properties of the Momordica charantia plant stem fibers are suitable materials as a reinforcement for the development of the biocomposite for potential applications.

Hybridization of natural fibers in polymeric composites is used in various applications due to its many advantages. The present study deals with the development of four different tri-layer composites by varying the stacking sequence of areca sheath and palm leaf sheath fibers with epoxy as a matrix by conventional hand lay-up process. The assessment of the developed composite’s properties was done by analyzing tensile, flexural, compression, impact, shore D hardness, water absorption as per ASTM (D 638-14, D790-10, D695-15, D256-10, D2240-15, D570-96, respectively). It was found from the test results that the composites with skin layers of areca sheath and a core layer of palm leaf sheath fibers showed better mechanical properties with a higher ultimate tensile strength of 46 MPa, ultimate flexural strength of 51 MPa, ultimate compression strength of 54 MPa, and reduced water absorption proving its suitability for lightweight applications. A scanning Electron Microscope highlighted the fiber bonding, and void characteristics of the tested composites.

The early success of wireless sensor networks has led to a new generation of increasingly sophisticated sensor network applications, such as HP's CeNSE. These applications demand high network throughput that easily exceeds the capability of the low-power 802.15.4 radios most commonly used in today's sensor nodes. To address this issue, this paper investigates an energy-efficient approach to supplementing an 802.15.4-based wireless sensor network with high bandwidth, high power, longer range radios, such as 802.11. Exploiting a key observation that the high-bandwidth radio achieves low energy consumption per bit of transmitted data due to its inherent transmission efficiency, we propose a hybrid network architecture that utilizes an optimal density of dual-radio (802.15.4 and 802.11) nodes to augment a sensor network having only 802.15.4 radios. We present a cross-layer mathematical model to calculate this optimal density, which strikes a delicate balance between the low energy consumption per transmitted bit of the high-bandwidth radio and low sleep power of the 802.15.4. Experimental results obtained using a wireless sensor network testbed reveal that our architecture improves the average energy per bit, time elapsed before the first node drains its battery, time elapsed before half of the nodes drain their batteries, and end-to-end delay by significant margins compared with a network having only 802.15.4.

This poster presents techniques for energy efficient operation of the Stargate wireless platform. In addition to conventional power management techniques such as dynamic voltage and scaling and processor shutdown, the Stargate features several mechanisms for energy efficient operation of the communication subsystem, such as support for hierarchical radios, Bluetooth based remote wakeup, mote based wakeup, etc. Finally, design optimizations including the use of power gating, and provision for battery-state aware operation are also described.