Effect of Stem Diameter, Moisture Content and Cutting Speed on Cutting Force for Groundnut Harvesting.

To design,and develop harvesting machines, the most important optimized parameter is the cutting force.The study was conducted to investigate the effect of stem diameter, moisture content, and cutting speed on the cutting force required for cutting groundnut stalks. The cutting force was measured using the reciprocating cutter bar test rig. Experiments were carried out at three levels of moisture content (40 - 47, 47 – 53, and 53 – 60 %) (wet basis), three levels of crop stem diameter (15- 17, 17 – 19, and 19- 21 mm) and three levels of cutter bar speed (0.80 – 0.90, 0.90 – 1.00 and 1.00 – 1.10 ms-1). The cutting force required for cutting groundnut crop stem was calculated for all the treatments. It was observed that increase in stem diameter, the cutting force increased by 19.83 % and increase in moisture content and cutter bar speed,the cutting force decreased by 37.57 %, and 34.11 %, respectively. The required cutting force (100 - 120 N) and energy (1.5 - 2.0J) was minimum at the cutter bar speed of 1.00 - 1.10ms-1 for 53 – 60 % moisture content, 15 - 17 mm stem diameter and they were maximum at cutter bar speed of 0.80 – 0.90 ms-1 (140- 160 N and 2.5 – 3.0 J)for 40 – 47 % moisture content, 19 – 21 mm stem diameter. The results showed that the cutting force requirement was increased with an increase in stem diameter and decreased with an increase in moisture content and cutting speed.

Analysis of the interaction effects between double shaking tables and test structure

Electrohydraulic shaking tables provide a direct means to evaluate structural performance under actual vibration conditions. The control–structure interaction is one of the most important reasons for the degradation of the control performance of the shaking table. This article establishes a series of novel analytical models to investigate the control–structure interaction effects between double shaking tables and test structure. These models are the model of shaking table, the model of control error signal, the flow requirement model of servo valve, the force requirement model of actuator, and the resonance response model of structure. Based on the analytical models of the flow requirement model of servo valve, force requirement model of actuator, and resonance response model of structure, a comprehensive simulation study is conducted under different structural conditions. The study reveals the influence trend and the influence degree of the control–structure interaction on the models. Furthermore, the applications in experiments, the suggestions for the designing of the shaking table, and the deeper explorations of the control–structure interaction are obtained.

A Test Rig to Characterize the Friction Force of Reciprocating Seals Under Dynamic Linear Motion

Seals are used in rotary and linear motion applications as barriers to protect components and equipment from hazardous materials and particulates. Although studies have presented research to characterize seals under rotary motion, performance of seals under linear motion have not been studied in details. In this research paper we will present a test rig and a systematic approach to understand and characterize seals under different conditions for linear motions. We investigate the effects of temperature, pressure and compression (squeeze) on force requirement. These factors are important for applications in oil and gas, manufacturing, combustion to name a few. A unique setup is built to test and gather information on different parameters to characterize seal behavior. Results from the study will be useful for design of components that use seals.