### Novel Methods, Techniques, Devices, and Computer Applications Developed

#### Investigator

#### Linear Knife Grid Size Reduction Shearing Device

A linear knife grid device with cross-lapped knifes, which allows for three different spacing (1², 2², and 4²), capable of determining the cutting characteristics of fibrous biomass was designed, fabricated, and successfully tested. This experimental device demonstrated that the shear dominant cutting operation would be the most energy efficient (≈ 1/4 energy for corn stover, and ≈ 1/10 for switchgrass) when compared to the reported hammer-mill based energy values.

#### Cutting Force Measurement Using Digital Torque Wrench

Garden lopper attached with a socket in combination with digital torque wrench rapidly measures the force or energy required to cut biomass. Such measurement usually needs an expensive universal testing machine, which was used only for calibration of this simpler inexpensive technique. A clear linear calibration relationship was observed.

#### Field Drying Baskets for In-situ Moisture Relation Measurement of Corn Stover

Measurements of moisture relation such as moisture desorption and adsorption of corn stover biomass in the field condition was challenging. The measurement on field was carried out efficiently using the designed and fabricated 2.5 m by 2.5 m steel baskets loaded with stover. This in-situ measurement of the experimental material ensured continuous accurate moisture relation data for further analysis.

#### Macro-Porosity of Wood Pellets

Accurate direct measurement of macro-porosity of wood pellets in bulk was not readily available. The developed novel method utilized the geometrical (cylindrical) shapes of the pellets. The rough ends of the pellets were sanded to form perfect cylinders, and whose volume can be determined using the mathematical formula from the measured dimensions. Filling a known volume with such “cylindrical” pellets, whose original volume is already known, the macro-porosity can be easily determined.

#### Dimension Measurements of Particles by Machine Vision

Most of the available image processing software fit an ellipse for each particle and report the major and minor axes, which always were demonstrated to deviate from the particles actual length and width. Two Java plugins based on 1) shape identification and correction factors and 2) pixel marching from centroid were developed to properly measure the orthogonal dimensions of convex objects from their images.

#### Simulation of Mechanical Sieving for Particle Size Distribution by Machine Vision

Standard particle size distribution method using mechanical sieves and shaker, a routine laboratory procedure, was simulated using images of particles. The algorithm used the ASAE S424.1 standards, reported the standard outputs, and suggested selection of sieves for balanced distribution of material on sieves. Provision was also made to manually select the sieves for analysis.

#### Sieveless Machine Vision Based Particle Size Distribution

The standard mechanical sieving method was shown to produce significant misclassification owing to “falling-through” effect of longer particles through sieve perforations. A sieveless machine vision based method was developed that produced a true-classification of all identified distinct length particles and analyzed for particle size distribution (PSD) as well as several PSD related parameters automatically. It was found that more than 50 or 75 sieves were required to match the PSD obtained from the sieveless method based on distinct particles grouping (virtual sieves).

#### Airborne Wood Pellet Dust Size Distribution by Computer Vision

Size and size distribution of airborne dust particles require highly expensive sophisticated instruments (e.g. laser diffraction, Coulter counter). The developed technique uses an inexpensive scanner and free open source ImageJ software. The developed user-coded plugin measured the length and width of the airborne particles and analyzed the particle size distribution, and the results were output in graphical and text formats.

#### Corn Stover Hygroscopic Moisture Sorption from its Components

(Ref.: Igathinathane et al, 2009, Applied Engineering in Agriculture 25: 65-73)

Consistent, accurate, and non-contact measurements of irregularly shaped chicken breast dimensions (length and width) were determined from the digital images. The developed machine plugin extracted the boundary profile, performed rotational transformation on the profile, established the enclosure box from which evaluated the length and width.

#### Dimensional Measurement of Chicken Breast by Computer Vision

Consistent, accurate, and non-contact measurements of irregularly shaped chicken breast dimensions (length and width) were determined from the digital images. The developed machine plugin extracted the boundary profile, performed rotational transformation on the profile, established the enclosure box from which evaluated the length and width.

#### Development of a Modified Warner-Bratzler Shear Testing Device

The original Warner-Bratzler shear device has a blunt edge notched plate (blade) that was actually meant for testing the toughness or tenderness of meat, fish, sausages, and similar softer materials. To test the tougher biomass materials, the business edge of the notched blade was modified into a sharp cutting edge, hence termed as “Modified Warner-Bratzler” shear device. In combination with a universal testing machine this device was successfully utilized to test the cutting strength of individual stems of switchgrass, corn stalk, wheat straw, and hickory wood, and could be extended to similar biomass.

#### Tamarind Pod Huller

The device works on the principle of bending the pods to break the shells. Rough surfaced huller rings arranged in zigzag manner does the hulling.

#### Laboratory Model Rotary Tray Dryer

Used for determining the drying characteristics of sliced vegetables or fruits. The tray holding the slices can be rotated manually to expose both surfaces of the slices to the drying air.

#### Multi-nozzle Spray Boom Attachment for Knapsack Sprayer

The five-nozzle boom can be directly attached to the existing air compression knapsack sprayer. The existing sprayer comes with single nozzle lance, but readily handles the multi-nozzle boom. The developed attachment was inexpensive, had a height adjustment mechanism, and produced increased spray coverage.

#### Flexible Multi-crop Thresher

On the specially designed and cast side discs, threshing cylinder types, such as, loop, peg, rasp bar, and angle bar replaceable elements can be fitted to have obtain different threshing cylinders – making it as a true “multi-crop” thresher.

#### Flexible Grader for Fruits and Vegetables

Thickness grading into four different grades using rollers (concentric aluminum tubes with steel rods for support) and manual conveying. The spacing between rollers can be adjusted on the slotted side support to suit different crops and desired grades.

#### Laboratory Model Accelerated Tempering Vessel

The designed and fabricated accelerated tempering vessel has the provision for controlling the vacuum, monitoring the relative humidity and vacuum, measuring the grain temperature, and quick loading and unloading features.

#### Color Index from Lovibond Tintometer for Color Comparison

The color values from the Lovibond tintometer (R, G, and B components) can be combined with certain constants to produce unique color index values. These indices can be used to compare the color of samples.

#### True Volume Measurement Device for Granular Materials

The instrument is made of glass and works on the principle of vacuum compensation. With the developed calibration chart and equations, the material true volume or porosity of the test granular material can be determined.

#### Viscosity Measurement of Liquids Using Simple Burette

The time required to discharge a given volume from a burette is a function of the liquid’s viscosity. Calibration equations were developed to correlate the non-dimensional discharge time and the actual viscosity using standard Redwood viscometer.

#### Weirs with Simplified Discharge Equation - Parabolic Weir

The discharge equations of all the sharp crested weirs generally have 1/3, 3/2 and 5/2 as exponents of the head causing the flow. These fractional indices make the calculation difficult by hand. Mathematically derived weir profile that has 2 as the exponent of head was parabolic in shape. Four weirs were designed, fabricated and tested.

#### Photovoltaic Leaf Area Meter

The leaf area meter based on the novel idea of utilizing the solar photovoltaic panel of the solar lantern was designed, developed and tested successfully. The principle of area measurement was correlating the variation in the voltage produced by the panel due to the obstruction caused by the samples to the lamp radiation and area determined from the developed calibration equations. Errors observed from the leaf samples tested varied from -3.37 to -0.13%.

#### Sofware for Leaf Area Measurement

A software which mimics the action of digital planimeter was developed in “Visual Basic.” Several dimensional parameters including the area were derived from the drawn profile. Provisions in the software were made to automatically connect the ends, erase the profile for correction purpose, fill the bounded area with any color, and record the point’s coordinates and other results in tabular and file format.

#### Surface Area of Ellipsoids - Method of Sections

Food materials resembling ellipsoids were “numerically” sectioned into elliptical discs. The individual lateral surface area of the discs was obtained by numerical methods from their perimeter and thickness, and the total surface area of the ellipsoid by assembling the discs.

#### Surface Area of Ellipsoids - Method of Triangles

Developed mathematical computer model evaluated the surface area considering the surface of the ellipsoid as a network of triangles in three-dimensional space (wire-frame model of surfaces). Owing to symmetry, it is enough to consider one eighth (1st octant) of the surface.

#### Ready Reckoner Table of Surface Area of Ellipsoids

Based on the method of triangles and employing non-dimensionalizing technique a ready reckoner surface area table was developed, which required only the principal dimensions of the ellipsoids.

#### Simplified Regression Equation for Surface Area of Ellipsoids

A simplified regression equation was developed to evaluate the surface area of general ellipsoids based on the already developed ready reckoner surface area table. This equation was handy and directly evaluated the surface area and can be considered as an empirical equation. This method could substitute for the model and the reckoner surface area table.

#### Numerical Decimal Search Technique

This indigenous numerical decimal search technique finds the maxima or minima of a continuously varying discrete data (unimodal functions) by progressive refinement. The technique was used in finding the best diffusion coefficient by minimizing the sum of squared deviation between the observed and the predicted characteristics.

#### Mathematical Modeling of Pre-conditioning of Wheat

Moisture diffusion equation in spherical co-ordinate system was solved using finite difference method to simulate pre-conditioning process of wheat. Diffusion coefficients of wheat starch and bran were determined, using which the moisture profiles during conditioning were evaluated.

#### Mathematical Modeling of Drying of Parboiled Paddy

(Ref.: Igathinathane and Chattopadhyay, 1997, Journal of Food Engineering 41: 89-101)

Diffusion equation simulating drying process was solved with prolate spheroidal co-ordinate system (PSCS) considering paddy as a multi-component prolate spheroid using finite difference method. PSCS was never used in the area of food engineering mathematical modeling. Diffusion coefficients of the parboiled paddy components, such as, starch, bran and husk were determined.

#### Mathematical Modeling of Tempering of Parboiled Paddy

(Ref.: Igathinathane et al., 2008, Journal of Food Engineering 88: 239-253)

Solving diffusion equation using prolate spheroidal co-ordinate system with multi-component prolate spheroid geometry using finite difference method simulated the tempering process. Insulated boundary condition made the moisture to flow from inside and equilibrate eventually.

#### Accelerated Tempering in Multi-pass Drying

Conventional tempering of parboiled paddy is a time consuming operation (6 to 8 h, or overnight). The new accelerated tempering process utilized vacuum to enhance the moisture diffusion, thereby achieving quicker completion. When compared with the control method (atmospheric pressure), a time reduction of 72% in the total processing time at 700 mm of Hg of vacuum was obtained.

#### Combinational Hot Soaking of Paddy

Soaking of rough rice is the most time-consuming operation in the parboiling process. A combination soaking procedure, involving 80°C water as the first-stage until an intermediate moisture content of 35.0% d.b., followed by 70°C as the second-stage up to the saturation moisture content of 42.7% d.b., resulted in a 67% time reduction when compared with single-stage soaking at 70°C. Based on this procedure a two-stage soaking operation separated around the gelatinization temperature can be recommended to grains that a need soaking operation in the processing flow.