Speed Of Cylinder Research Articles

Design and Performance Assessment of Dual-Speed Axial Threshing and Separation for Paddy Rice Combines

HighlightsDual-speed axial threshing and separation was designed to improve performance.Loosely connected grains were removed firstly for reducing opportunity for breakage.Machine is complex but a lower effective cylinder speed can reach a good performance.Reasonable feed rate and concave clearance could maintain quality and throughput.ABSTRACT. This research was conducted to assess the performance of a combine, model number 4LZ-4.0 under different threshing functional parameters such as speed of high/low speed cylinder, cylinder-concave clearance and linear speed of concave sieve. An indoor experiment was conducted using the dual-speed axial threshing and separation. These functional parameters were set at five levels. The responses were obtained in terms of broken rate, impurity rate and loss rate. Multi-objective variable optimization was performed using Design-Expert 6.0.10 software. Analysis of variance was done to determine the significant effects of the factor variations on the response values. Design-Expert 6.0.10 software was used to present response surface graphs that were used to describe the variations of the responses as the factors changed from one level to the other. Results showed that with an increase in speed of high/low speed cylinder from 15.42/18.50-22.92/27.50m/s, the percentage of broken rate increased significantly from 0.15% to 1.13%, respectively. At cylinder speeds of 15.42/18.50m/s and 22.92/27.50 m/s rpm, the impurity rate increased from 0.31% to 1.62%, respectively. It was also realized that varying the speed of high/low speed cylinder had a significant effect on the broken rate and impurity rate. The impurity rate increased with an increase in Linear speed of concave sieve from 0.40 to 1.60 m/s, the percentage of impurity rate increased significantly from 0.31% to 1.62% respectively. However, the lowest impurity rate was obtained at an average linear speed of concave sieve of 0.99 m/s. Furthermore, it was realized that increasing the cylinder-concave clearance from 16 to 30 mm, equally increased the percentage of loss rate from 1.78% to 2.93%. From the results obtained, it was suggested that operating the threshing cylinder at a speed of high/low speed cylinder of 18.31/21.97 m/s, cylinder-concave clearance of 22.60 mm and linear velocity of rotary concave of 0.99 m/s, gave a better performance of the machine. Keywords: Axial threshing and separation, Cylinder-concave clearance, Dual-speed, Functional parameters, Linear speed of concave sieve, Speed of high/low speed cylinder.

Optimization of Conventional Combine Harvester to Reduce Combine Losses for Basmati Rice (<i>Oryza Sativa</i>)

A study was conducted at PAU Regional Research Station, Gurdaspur (Punjab) to investigate the design and operational parameters of threshing mechanism of conventional combine harvester for basmati crop. This study was aimed to investigate the suitable changes required in the self-propelled conventional combine harvester for harvesting the basmati crop with minimum grain losses. Field evaluation of experiment was carried out to assess the influence of independent design variable i.e., arrangement of spikes (AS) and independent operational parameters such as concave clearance (CC) and cylinder speed (CS). The study was aimed to enumerate various combining losses viz., extent of visible and invisible grain damage and threshing efficiency at different AS, CC and CS levels. The first year data recorded during 2017 were processed for the optimization during 2018. The results of the present study revealed that during 2017, maximum visible and invisible losses was 5.49% ± 0.33% and 28.07% ± 3.21%, respectively whereas after modification, these losses remained only 4.00% ± 0.80% and 24.07% ± 2.86%, respectively. The threshing efficiency remained above 99.31% ± 0.47%, for both years. Thus, optimization of combine harvester was able to save the visible grain damage by 60% to 83% and invisible grain damage by 6% to 16%, respectively during 2018 than the year 2017.

Investigation of thermal conductivity of orange and tangerine juices in non-stationary state

Thermal conductivity is one of the main thermophysical properties of liquid food products, including fruit and vegetable juices. Known experimental installations measure the thermal conductivity of stationary liquids. This results in significant deviations from the actual numbers. A method of determining the thermal conductivity of a fluid in motion and an experimental installation implementing the proposed method are suggested. The developed experimental installation consists of two coaxial cylinders: internal and external. A gap between cylinders is filled with analysed liquid. The object of the study was the juices of subtropical fruits, such as oranges, tangerines grown in the subtropical regions of the Republic of Azerbaijan. In this work, the thermal conductivity of juices was also investigated during forced movement on an installation also consisting of two coaxial cylinders. Experimental measurements of thermal conductivity for orange and mandarin juices were carried out. Experiments were carried out at frequencies from 50, 100, 150 and 200 s-. A general description of the dependence of thermal conductivity on temperature, dry matter concentration and rotational speed made it possible to develop a model, in particular for orange juice. The described method and experimental installation for measuring the thermal conductivity of a liquid in a non-stationary state made it possible to develop a mathematical model describing the dependence of thermal conductivity on temperature, dry matter content and cylinder speed.

Synthesis and Electrochemical Performance Analysis of LiNiO2 Cathode Material Using Taylor-Couette Flow-Type Co-Precipitation Method

A LiNiO2 cathode material with a layered structure and a high capacity was synthesized by co-precipitation with Taylor−Couette flow. Taylor−Couette flow is caused by the rotation of an inner cylinder in a device consisting of two concentric shaft cylinders. A regular donut-shaped vortex is developed above a certain rotational speed of the inner cylinder. Ni(OH)2 precursors synthesized by co-precipitation with the Taylor–Couette flow were sintered at 600 °C, 650 °C, 700 °C, and 750 °C. The LiNiO2 cathode material synthesized at 700 °C exhibited the highest discharge capacity of 233 mAh g−1. It was confirmed that the cyclability and rate performance of the LiNiO2 cathode material improved at other sintering temperatures.

Combined pneumatic drive of the rotary-dividing mechanism of the revolver head

Currently, the use of a positional combined drive in metal-cutting equipment must have a high-precision ability to process new materials, the design of workpieces and parts; ensure the technical and environmental safety of personnel, etc. All these requirements must be met by CNC machines to produce competitive products in the market criteria. Metal cutting equipment due to its high cost has led to the need to use a single power source for multiple work movements. To increase the productivity of the machine, it is necessary to use a combined two-motor positional pneumatic drive. This increases the total production time. reduce the main time (by automating two movements: rapid supply of the workpiece to the processing center, and reduce the auxiliary time (automating the installation of the workpiece and removing the part, reducing the path of movement of the tool), reduce the time for equipment changeover (using digital display and software control). The section “research results” presents the results of mathematical modeling based on a computer model implemented in the SimInTech software package. The graphs of pressure dependences in the piston and rod cavities of the pneumatic cylinder, speed and displacement of the pneumatic cylinder are obtained.

The effect of fluid flow on CO2 corrosion of high-strength API carbon steels

This paper presents and discusses the outcomes of a recent study on the corrosion resistance of API carbon steels (T95 and Q125). The scope includes experimental investigation as well as theoretical modeling. To predict CO2 corrosion under dynamic conditions, an existing model is improved and validated using experimental measurements.Corrosion tests were conducted under static and dynamic conditions. API casings were cut and machined to prepare test specimens used for measuring Average Corrosion Rate (ACR) and Load-Carrying Capacity (LCC). The dynamic test condition was simulated using the flow between two concentric cylinders (Couette type flow). The test solution (2% wt. NaCl) was saturated with a gas mixture containing 50% CO2 and 50% methane. Tests were carried out at 41.37 MPa with varying temperature and the speed of the inner cylinder, and subsequently, changing the wall shear stress (τw). The ACR was determined by applying the Weight Loss (WL) method. A digital microscope was utilized to inspect the morphology of the corrosion scale (product). The change in LCC of the specimens was compared with the theoretically predicted change in LCC to identify the presence of localized corrosion and/or intergranular attack. In addition to LCC, the ultimate tensile strength (UTS) of corroded specimens is determined and compared with that of uncorroded specimens.Results show that the CO2 corrosion of API steels is sensitive to the fluid velocity regardless of temperature. The corrosion of Q125 is more affected by fluid flow than that of T95. Below critical shear stress, CO2 corrosion was strongly affected by fluid flow. Under a static condition, Q125 demonstrated higher corrosion resistance than T95 but under a dynamic condition, T95 exhibited higher corrosion than Q125. At high temperature (71 °C), the occurrence of localized corrosion was observed. Corrosion model predictions show reasonable agreement with measurements.

Development of a decorticator for Buchanania lanzan nuts and its process optimization

AbstractThe study was aimed to develop a decorticator and to standardize the process for separation kernels from nuts. The developed machine was optimized using independent parameters, that is, cold water soaking, steaming, and sand roasting, different moisture levels (7 and 9%), cylinder speed (150 and 300 rpm), and concave clearances (7.5 and 8 mm). The optimum performance of a developed decorticator was obtained when sand roasted nuts (7% moisture content) fed at a cylinder speed of 300 rpm and a concave clearance of 8 mm. At this condition, decortication efficiency, capacity, and whole kernel recovery were 96.10, 64.15, and 12.60%, respectively. The decorticator produced 126 g whole kernels (56.71%) from 1 kg of nuts. The independent process parameters have significant effect on response variables. The machine had low labor requirement, high efficiency, and ease to operate; thus, the results will be useful for processing of nuts and in other studies.Practical applicationsThe chironji nut decorticator has application to decorticate nuts to produce kernel at manufacturing site of food, flavor, cosmetic, and pharmaceutical industries. The kernels have very short shelf‐life because they are very soft and susceptible to mechanical damage and spoilage. The available decorticators have very limited efficiency and more breakage thus the results can be utilized to fill existing gap to obtain increased efficiency and less damage. The results of different treatments to nuts will assist future studies as well.

Using a Couette–Taylor vortex flow reactor to prepare a uniform and highly stable Li[Ni0·80Co0·15Al0.05]O2 cathode material

This study mainly focuses on the preparation technique of Ni-rich NCA hydroxide by a Couette–Taylor flow reactor (CTFR), by systematically optimizing the preparation parameters, including cylinder rotation speed and calcination temperature to study its electrochemical performance. Because of the uniform mixing and constant fluid motion of the Taylor vortex, we obtained spherical and uniform Ni0·80Co0·15Al0·05(OH)2 particles. The rotation speed of the inner cylinder determined the degrees of particle agglomeration and growth. X-ray diffraction and Rietveld refinement revealed that the sample prepared at 600 rpm had relatively large particles and a high degree of crystallinity; when calcined to 750 °C, it featured much smaller primary particles, a comparatively lower degree of cation mixing, and better layer structure ordering. The Ni-rich LiNi0·80Co0·15Al0·05O2 prepared under the optimal conditions delivered a high discharge capacity of 190.6 mAh g−1 at 0.1C, on par with that of commercially available NCA powders; it also exhibited a remarkable improvement in rate capability, with a discharge capacity of 138 mAh g−1 at 10C (101 mAh g−1 for a commercial sample). In long cycle life tests, the prepared NCA sample retained a high capacity (87.4%) after 100 cycles at 1C, compared with 70.0% for the commercial sample. Furthermore, cyclic voltammetry and electrochemical impedance spectroscopy demonstrated the importance of the calcination temperature on the electrochemical performance and structural stability of our Ni-rich cathodes. Our as-prepared NCA cathode materials, obtained using a CTFR, appear to have great potential for application in Li-ion batteries.

Experimental study on the key factors of low-loss threshing of high-moisture maize

The rates of maize breakage and entrainment loss are high in the harvest of high-moisture maize, which remains an issue with the development of agricultural mechanization. In order to reduce the maize breakage and entrainment loss rates, the correlations among key factors, such as the threshing cylinder speed, concave clearance and feeding rate, and the rates of breakage and entrainment loss during high-moisture maize harvesting were studied in this paper. A single-factor experiment was carried out using a single-longitudinal-axial flow maize harvester, and an orthogonal experiment was carried out using single- and double-longitudinal-axial flow maize harvesters with the Taguchi experimental design method. The single-factor experiment revealed that when the cylinder speed increased, the breakage rate of maize decreased first and then increased, while the entrainment loss rate decreased. The breakage rate of maize decreased as the concave clearance increased, while the entrainment loss rate decreased first and then increased. The optimum value of the concave clearance was positively correlated with the ear diameter of maize; Additionally, the minimum breakage rate of maize occurred when the feeding rate was at the rated value, and the entrainment loss rate increased as the feeding rate increased. The orthogonal experiments revealed that the importance of cylinder speed, feeding rate, concave clearance on the maize breakage and entrainment loss rates were in descending order. The optimum values of parameters for the single-longitudinal-axial flow maize harvester were 370 r/min cylinder speed, 40 mm concave clearance and 10 kg/s feeding rate. The optimum values of parameters the double-longitudinal-axial flow maize harvester were 550 r/min cylinder speed, 35 mm concave clearance and 10 kg/s feeding rate. The research can provide a reference for parameter configuration and control strategy for the longitudinal-axial flow maize harvester with high-moisture maize. Keywords: high-moisture maize, maize harvester, parameter configuration, Taguchi experiment DOI: 10.25165/j.ijabe.20201305.5653 Citation: Zhu X L, Chi R J, Du Y F, Qin J H, Xiong Z X, Zhang W T, et al. Experimental study on the key factors of low-loss threshing of high-moisture maize. Int J Agric & Biol Eng, 2020; 13(5): 23–31.

Design and evaluation of self-unloading grain collection system for tractor operated axial flow paddy thresher

India is the second largest country in world with population of 1.356 billion (Census 2017). Rice (Oryza sativa) is one of the most important cereals and it is staple food for more than 60% of the world population. The performance evaluation of thresher was studied on paddy variety Mahamaya to ascertain the effect of feed rates(4.5t/h,5.0t/h,5.5t/h), moisture content (13%, 15%, 17%) and cylinder speed (15.54m/sec,17.27m/sec,19.42m/sec) with four replication. The threshing efficiency, cleaning efficiency, threshing capacity and total losses were 99.42%, 98.91, 2.5t/h, 0.4% respectively at the best and optimum combination of feed rate, moisture content and cylinder speed of 5.0t/h,15% and 17.27m/sec respectively. Self unloading system of thresher was design and developed by using CATIA V5 2014.There was a cost saving of 2.86%/h and labour saving of 50% over earlier practice.

Specific energy consumption of a Moringa oleifera seed shelling machine

In this work, the Specific Energy Consumption (SEC) and machine capacity for a Moringa oleifera seed shelling machine were determined in relation to the cylinder speed and seed sizes. A M. oleifera seed shelling machine was tested and the SEC was appraised. The SEC and machine capacity of the M. oleifera seed shelling machine were determined at five speed levels, viz. 200, 240, 280, 320 and 360 rpm using three seed sizes (viz. small, medium and large seed sizes). The SEC and machine capacity increased with the seed sizes during the shelling process. The same trend was observed for the relationship between the SEC and cylinder speed. The minimum values obtained for the SEC using the small, medium and large M. oleifera seed sizes were 31.25, 40.07 and 54.22 Wh·kg<sup>–1</sup>, respectively, at a cylinder speed of 200 rpm while the maximum values obtained for the small, medium and large seed sizes were 58.01, 74.37 and 100.63 Wh·kg<sup>–1</sup>, respectively, at a cylinder speed of 360 rpm. The optimum values obtained for the machine capacity were 14.58, 11.38 and 8.41 kg×h<sup>–1</sup> using the small, medium and large seed sizes, respectively. Conclusively, this study shows that the SEC and machine capacity were affected by the variation in the cylinder speed and seed sizes.

Modelling and simulation of the grain threshing process based on the discrete element method

A modelling and simulation method was developed to comprehensively describe and quantify the unmeasurable dynamic threshing process based on the discrete element method (DEM). To establish a simulation model of rice plants, experiments were carried out to determine the relevant biological and mechanical parameters. A discrete element model of rice plants was established using hollow cylindrical elastic bonds. The complex threshing process of grain was simulated. Through the threshing simulation, the dynamic behaviour of flexible rice plants under large deformation, fragmentation and multiple interaction conditions was accurately described at the particle level. The cumulative distribution of the separated grains obtained by the simulation was consistent with the experimental results. The maximum relative error of the grain separation rate between the simulated and experimental results under different feeding rates was 11.2%. The impact force distribution, grain flow field distribution, threshed grain percentage and grain separation rate during the threshing process could be easily obtained by the simulation. The threshing simulation could predict the effects of the feed rate, cylinder speed, threshing gap and rolling friction on the threshing performance.

Optimal Design of a Filter Media by Tuning the Structure of Needle Punched Nonwoven: Influence of Carding Parameters

This research work investigated the influence of carding parameters on different properties. In this study an attempt has been made to change the fibre orientation by changing the carding parameters such as feeder speed, cylinder speed and doffer speed keeping the same areal density of fabrics. In a combination of three different levels of feeder, cylinder and doffer speeds were also considered for sampling plan to create a three-factors three-levels Box-Benkhen Design for a better explanation of results. The fibre orientation was measured by using both direct (image analysis) and indirect (lindslay’s cutting and combing) method. The properties such as bursting strength, filtration efficiency and pressure drop were evaluated. The properties were analyzed and explained in the light of fibre orientation. It was found that the considered carding parameters influenced the fibre orientation to a great extent and the properties are influenced by the fibre orientation. In the end, an overall optimization has been done to achieve maximum filtration efficiency with minimum pressure drop and moderate busting strength.

Characterization of Recycled Silk Fiber PP Composites with Optimal Performance of Silk Fibers by Response Surface Methodology

Abstract This article emphasizes the optimization of the retrieval of silk fibers from silk selvedge waste in a hard waste opening machine. It also highlights the characterization of composites developed from retrieved silk fibers with a polypropylene matrix in a compression molding machine. The machine conditions of the hard waste opener, such as the licker-in speed, cylinder speed, and setting between feed roller to licker-in, were optimized with respect to the fiber staple length using the Box-Behnken experimental design with response surface methodology. The optimum conditions for the fiber staple length were found to be licker-in speed, 550 r/min; cylinder speed, 280 r/min; and setting between feed roller to licker-in, 0.01 inch. Composites were developed using the silk fibers retrived at optimum conditions with polypropylene resin in compression molding at three different fiber loadings, namely 40, 50, and 60 weight % of silk fibers. The influece of silk fiber loading on the mechanical and thermal properties of the composites were studied and compared to pure PP composite. It is observed from the results that the composite with 50 weight % of silk fiber loading has shown greater mechanical properties. Furthermore, the incorporation of silk fibers in the polypropylene matrix has shown an improvement in the mechanical properties of 71.6 %, 76.66 %, 69.73 %, 67.97 %, and 58.45 % for tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength, respectively, in the composites when compared to pure polypropylene composite. The Differential Scanning Calorimetry analysis has also shown an increase in the degradation temperature of 8°C in the silk fiber-reinforced composite.

Assessment of the effectiveness of the regenerative suspension of a timber truck based on the results of simulation

The relevance of using various recuperative mechanisms in vehicle suspensions is justified in order to reduce fuel consumption and improve their environmental performance. The developed hydraulic drive scheme and a mathematical model of the movement of a forest car equipped with a suspension with a recuperative mechanism are presented. An assessment of the effectiveness of the regenerative suspension of a timber truck was carried out according to the results of simulation. Analytical dependences of the influence of time, speed and diameters of recuperative suspension hydraulic cylinders on the values of recuperative power under various conditions of movement of a forest car are obtained.

Machine Crop Parameters’ Model of Spike - Tooth Thresher for Soybean

The goal of regular modification of threshing machine is to increase soybean processing efficiency. This study was carried out to deconstruct the thresher’s parameter - output relationship and to evolve a model for such relationship at the Engineering workshop of the Federal College of Agriculture, Ibadan, Oyo State Nigeria. Unthreshed soybeans, CGX14x1448 were used to evaluate the performance of a modified spike tooth thresher fabricated at the Workshop. The summary statistics of the machine output showed that concave clearance had percentage unthreshed soybean of 16.98%, percentage mechanically damaged seed of 8.625%, blown seed of 23.403kg and high seed loss of 44.241kg. Both the mean cleaning efficiency (94.175) and threshing efficiency (83.022) were very high. The trend of the cylinder speed however contrasts with those of concave clearance and moisture content. The percentage unthreshed (83.212%), percentage mechanical damage (16.792%) were in contrast to each other. Similarly, the threshing (44.108) and cleaning (23.321) efficiency were low. The relationships between cylinder speed and machine output showed an increasing trends for blown seed, percentage damaged seed and seed loss. Concave clearance - threshing efficiency can be predicted using 3 most parsimonious models (xy-inverse, exponential and simple linear model). High adjusted coefficients of determinations (R2) were obtained for the best model of cylinder speed - threshing efficiency model. These were 0.9997 for the xy inverse and 0.9998 for quadratic 0.993 for exponential model with estimation variance of 0.00047 (quadratic), 0.000 for inverse xy and 0.000191 (exponential model). The practical application of the models is in the specificity of the measurement of the relationship between thresher’s parameters and output.

Experimental Modeling and Optimization of a Free-Fall Electrostatic Separator Equipped With Four Rotating-Cylinder Electrodes

The four-cylinder electrostatic separator is a recent improvement of the “standard” free-fall equipment. The new design, which drastically reduces the inconveniences related to the impacts that might occur between the particles and the electrodes, has been adapted for applications involving the processing of micronized particles. Such applications require the use of a specific rotating-blade-type tribocharging device and an appropriate electrode cleaning system. The aim of the present work is to evaluate the effects of several factors that influence the performances of the new triboelectrostatic separator. The experiments were made on a binary mixture of polyvinyl chloride (PVC) and unplasticized PVC. The control variables considered in this study were the rotating speed of the central cylinder of the tribocharging device, the voltage applied to the electrodes of the separator, and the distance between them. The results obtained were excellent: The recovery rates and the purities of the separated products exceeded 95% for the optimum values of the control variables.

Surface pressure and viscous forces on inclined elliptic cylinders in steady flow

Surface pressure characteristics of elliptic cylinders of various thicknesses and orientations are investigated in steady flow regime. A stabilized finite-element method has been used to discretize the conservation equations of incompressible fluid flow in two dimensions. The Reynolds number, Re, is based on the major axis of cylinder and free-stream speed. Results have been presented for $$Re\le 40$$ and $$0^\circ \le \alpha \le 90^\circ $$ , where $$\alpha $$ is the angle of attack. Cylinder aspect ratios AR considered are 0.2 (thin), 0.5 and 0.8 (thick). It is found that a decrease in AR does not significantly alter the location of minimum surface pressure for $$\alpha = 90^\circ $$ , but the value of minimum pressure decreases sharply, resulting in severe adverse pressure gradient. In contrast, for $$\alpha = 0^\circ $$ , the location travels towards the base and the minimum pressure increases, leading to delayed flow separation. In general, the magnitude of forward stagnation pressure at low Re is smaller than the maximum pressure for $$AR\le 0.5$$ . The maximum pressure occurs at the forward stagnation point as the Re and AR increase. However, in most cases, the locations of forward stagnation and maximum pressure points differ even when the pressure coefficients are very close to each other. The forward stagnation and maximum pressure coefficients of an elliptic cylinder decrease monotonically with increasing $$\alpha $$ . The drag of a circular cylinder in most cases exceeds the ones obtained for elliptic cylinders. With increasing AR, the drag increases approximately linearly for small $$\alpha $$ , lift decreases approximately linearly and moment decreases non-linearly. For a thick cylinder, while the effect of Re on lift and moment is insignificant, the drag shows a strong dependence. Roughly $$\alpha = 20^\circ $$ for $$Re = 40$$ flow represents a critical angle of attack below which a cylinder of $$AR\le 0.5$$ acts like a streamlined body and above, like a bluff body.

REKAYASA MESIN PENGUPAS KULIT BUAH KOPI JENIS ROBUSTA MODEL TEP-JLL 2015 DI KABUPATEN TANA TORAJA

ABSTRACT The objective of this research was to design a pulper machine model TEP-JLL 2015 for fresh coffee robusta used in rural areas of Tana Toraja district. The machine was designed based on the analysis of physical characteristics of Robusta Tana Toraja coffee and literature study. The analysis result of physical characteristics showed the average length, thickness width was 12.494 mm, 12.802 mm, 10.687 mm, respectively, and the bulk density was 1,115 kg/m3. The theoretical hopper capacity of this machine was 3.7687 kg. Assuming the cylinder speed was 111.594 rpm with an effective distance setting system or flawed setting of 1.2 cm, the theoretical capacity of this pulper machine was 380.62 kg/hour. Keywords: fresh Robusta coffee fruit, pulper machine

Real-time grain breakage sensing for rice combine harvesters using machine vision technology

Breakage rate is one of the most important indicators to evaluate the harvesting performance of a combine harvester. It is affected by operating parameters of a combine such as feeding rate, the peripheral speed of the threshing cylinder and concave clearance, and shows complex non-linear law. Real-time acquisition of the breakage rate is an effective way to find the correlation of them. In addition, real-time monitoring of the breakage rate can help the driver optimize and adjust the operating parameters of a combine harvester to avoid the breakage rate exceeding the standard. In this study, a real-time monitoring method for the grain breakage rate of the rice combine harvester based on machine vision was proposed. The structure of the sampling device was designed to obtain rice kernel images of high quality in the harvesting process. According to the working characteristics of the combine, the illumination and installation of the light source were optimized, and the lateral lighting system was constructed. A two-step method of “color training-verification” was applied to identify the whole and broken kernels. In the first step, the local threshold algorithm was used to get the edge of kernel particles in a few training images with binary transformation, extract the color spectrum of each particle in color-space HSL and output the recognition model file. The second step was to verify the recognition accuracy and the breakage rate monitoring accuracy through grabbing and processing images in the laboratory. The experiments of about 2300 particles showed that the recognition accuracy of 96% was attained, and the monitoring values of breakage rate and the true artificial monitoring values had good trend consistency. The monitoring device of grain breakage rate based on machine vision can provide technical supports for the intellectualization of combine harvester. Keywords: combine harvester, breakage rate monitoring, sampling box structure, machine vision, color classification DOI: 10.25165/j.ijabe.20201303.5478 Citation: Chen J, Lian Y, Zou R, Zhang S, Ning X B, Han M N. Real-time grain breakage sensing for rice combine harvesters using machine vision technology. Int J Agric & Biol Eng, 2020; 13(3): 194–199.