SBIR-STTR Award

Native Seedsters, Inc will test patented technology to recover camelina seed (Camelina sativa). Seedster principles appear apt for camelina. The Seedster counter-rotating brush and a combing drum form a `pinch point'. The comb teeth position seed stems. The brush dislodges seed and few impurities. Rapid brush rotation creates air to propel plucked seed into the conveyance system. Camelina grows on marginal soil in dry cool environments, such as the Northern Great Plains. The DOE/USDA SBIR Energy Summit urged small businesses to develop renewable energy technologies. Success of Seedster technology in camelina harvest would increase renewable biofuels with favorable energy balance. Camelina oil content, 35-40%, is excellent biodiesel feedstock. The large fraction of Omega-3 oil content, 34-39%, has superior nutritional qualities. Omega-3 oil amino acids in meal increase Omega-3 levels in eggs, milk, and meat. Acreage may soon pass a million acres in Montana. Yield range from 1000-2500 lbs/per acre. Production costs are $46.40/acre due to lower seed, fertilizer, and herbicide costs. Camelina biodiesel production costs average $1.45 per gallon. Pod shattering or seed carry-over from combines leads to camelina seed loss. Combines limit ground speed to 1-2 mph to separate material. Round, small, dense camelina seed in fragile pods when ripe, number 300,000-465,000 per lb. Increased seed recovery impacts the bottom line of the grower. If feasible a seed harvester will be designed that recovers a high percentage of standing crop, with a few hulls and stems, at high ground speed. OBJECTIVES: The Phase I goal is to establish the technical feasibility of harvesting camelina seed with Arbuckle Native Seedster technology of counter-rotating cylinders equipped with brushes or combs. There are several anticipated advantages of Seedster technology for harvesting camelina: higher percentage recovery of standing crop; cleaner seed with fewer impurities reduce processing costs; higher ground speeds lead to more productivity; lower purchase and operating costs; and smaller size and simplicity of the machine speed lower operating costs and speed set up and cleanout. An optimal configuration of comb drum diameter, comb shape, and brush diameter will be selected that is most effective at seed recovery. Native Seedsters, Inc. will achieve the following Phase I technical objectives: Task 1: Translate end user priorities and analysis of camelina seed morphology into design principles and performance standards. Address these questions: What attributes, performance parameters, and features of a harvester are the highest priorities for growers and processors for the harvest of camelina seed? Does the design as initially proposed conceptually address these parameters? What design modifications should be considered to transition the Phase I model in Phase II to better address producer priorities? Task 2: Design, model, and test a camelina seed dislodgement system by addressing the following questions. Can the Phase I model be reconfigured as counter-rotating combing drums, or as a counter-rotating brush and combing drum? Does the design address the fact that camelina is very shatter-prone? Does the model cause at least 90% of camelina pods to release seed? Does the seed dislodgement mechanism recover at least 95% of the released seed? Does Seedster technology capture at least 90% of the unbroken pods? Does high speed video (HSV) record seed and pod dislodgement/collection? What are the percentages of seed, unbroken pods, and chaff? Task 3: Confirm the technical feasibility of Seedster Camelina harvest technology in the field. Address the following questions: Is at least 90% of the existing camelina seed crop dislodged and captured as measured by hand harvested controls? If not, why not? Do non-seed impurities exceed 15% of the collected material? Is there excessive stem severing and if so what is the cause? What types of non-seed plant parts are captured? Does the model dislodge seed effectively at ground speed of 3 mph? Does HSV analysis document the dislodgement and transport of seed to be engaged by a pneumatic conveyance system? Successful Phase I achievement of performance standards anticipate Phase II activities, such as how to handle the fractions of seed, un-shattered pods, and impurities; conveyance, collection and unloading systems for pure camelina seed; and tests of the technology on dislodgement and recovery of canola seed. Finally comparative performance with combines will compare capital costs, operating costs, and seed recovery. APPROACH: Task 1: Translate producer priorities and the characteristics of camelina seed morphology into design principles and performance standards. Funded by Native Seedsters, Inc. ask a panel of 5-8 camelina producers and processors, what attributes, performance parameters, and features of a camelina harvester are the highest priorities for growers and processors? The PD will confirm the completed design addresses producer priorities. After shop trials and field validation the PD will confirm prototype performance meets producer priorities for a camelina harvester. Finally to prepare for Phase II the PD will ask, what design modifications could better address producer priorities in Phase II? Task 2: Design, model, and test a camelina seed dislodgement system. First, modify the existing test bed to accommodate the comb and brush types to be tested. Second, buy two types of brushes, a B1 brush that is 24 inch diameter brush on a 6 inch core with densely arrayed filaments of about 0.04 inch diameter, and a B2 brush that is 6 inch diameter filament to be selected. Third fabricate steel comb drum cores, a C1 comb drum core of about 12 inch diameter, and a C2 comb drum of about 6 inch diameter. Fourth, fabricate two sets each of two shapes of UHMW combs S1 and S2. The first shape will have teeth of a 0.075 radius at the tooth bottom. The second shape will be a new fluted shape with a radius appropriate to pluck un-shattered camelina pods from the stems. Analyze the effect on seed dislodgement of brush diameter, comb drum diameter, and different comb shapes by installing each on combing drums in different combination of B1, B2, C1, C2, S1 and S2. Select the best performing comb drum diameter. Select the best performing comb shape. Select a comb to brush configuration, a comb to comb configuration, or a brush to brush configuration for the counter-rotating shafts. Analyze and record observations and conclusions. Then in the shop do high speed video (HSV) analysis. Operate the test bed equipped with the selected components and configured with selected parameters for key variables. Native Seedsters, Inc. has an established protocol it follows for adaptive iterative HSV tests. Record images of test bed performance using recommended configurations. Devise sensitivity tests and record images. Do detailed analysis of the HSV images, and amend the conclusions drawn after the shop tests. Task 3: determine in the field the technical feasibility of using Seedster technology to harvest camelina. This will validate the findings and conclusions of shop tests and HSV analyses. Task 4: Summarize observations and conclusions from shop tests, high speed video (HSV) records, field trials, and MSU Seed Lab data to answer the following questions. Is at least 90% of the standing camelina seed crop dislodged, as measured by hand harvested controls? If not, why not? Do non-seed impurities exceed 15%? Is stem severing excessive and what is the cause? What is the nature of the non-seed impurities? Is seed dislodgement effective at 3 mph? What does HSV analysis document about dislodgement and pneumatic conveyance of seed?

Camelina seed production is expanding throughout the semi-arid portion of the wheat belt and is proposed for intercropping between rows in vineyards and nut orchards. These markets and the market need for small maneuverable harvesters for research plots and breeder blocks have created a need for an inexpensive, but efficient, camelina harvester. The Seedster has the potential for meeting the demand for a camelina harvester that is inexpensive, variable width, maneuverable, has quick seed unloading and rapid cleanout. In Phase I Native Seedsters, Inc. (NSI) tested the basic Seedster technology which consists of counter-rotating brush and combing drum. The space in-between the brush and comb creates a 'pinch-point' where seed is plucked from the plant inflorescence. The first harvest of camelina with a Seedster resulted in a product that was 50% (by weight) seed, 40% seed capsule halves and 10% stems. In commercial camelina seed production the receiving elevators allows only 4.5% tare. To improve upon the purity of Seedster harvested seed a screening device was designed and tested. This device consisted of semi-cylindrical 9/64" round-hole screen which housed a 9" auger. During the second year of the Phase I project the seed purity was improved from 50% to 97% with the addition of the screening device. Although Phase I met or exceeded 4 of the 5 Performance Goals, the seed recovery efficiency was still not high enough to be competitive. In Phase I, the 40" Test-Bed Seedster capture only 59% of the total seed from stands yielding 1,100 lbs/acre and 70% of the seed in stands yielding 550 lbs/acre. The seed loss was attributed to a) seed shatter upon initial contact with the main brush, b) seed carry over on the combing drum and c) seed that 'stalled out' in the dislodgement chamber and fell back out the pinch-point because of insufficient airflow to carry the seed all the way to the seed hopper. In the Phase I Test-Bed the majority of the airflow for transporting the dislodged seed to the seed hopper was created by the main brush, with supplemental air and direction created by the air assist brush. In Phase I this airflow was insufficient to transport all of the heavy, rounded camelina seed to the seed hopper. In Phase II, a 60" Test-Bed Seedster will be assembled that is capable of configuration and reconfigurations to address these seed losses. The air-assist brush will be replaced with a tangential flow fan, positioned behind the combing drum to direct and propel all dislodged seed from the dislodgement chamber into the collection hopper, eliminating carry-over on the combing drum. The combing drum will be adjusted forward, thus making the distance between the pinch-point and the point of initial contact closer, reducing initial shatter. Various brush bristle densities and various combing drum surfaces (greater static friction) will be tested for maximizing seed dislodgement. An 8/64" round-hole screen will be tested in the screening device to try to improve seed purity to 99%. If the Phase II Performance Goals are met the Seedster will be a viable camelina seed harvest alternative for many farmers and researchers. OBJECTIVES: Native Seedsters, Inc. (NSI) proposes to improve upon the harvest efficiency of camelina seed by making modifications to the patented Seedster technology. In Phase I NSI met or exceeded four of the five performance standards. The Seedster was able to dislodge 95% of the seed from the standing plants (90% target), had seed hopper purity of 97% (85% target), had 0 % damage to harvested seed (2% target) and was able to harvest at 3 mph or faster. However, total seed recovery ranged from 59% (stands yielding 1,100 lbs/acre) to 70% (stands yielding 550 lbs/acre) (90% target). The seed loss was attributed to a) premature shatter when the plants first came in contact with the main brush, b) carry-over on the combing drum and c) seed that was not sufficiently propelled through the dislodgement chamber and fell back through the pinch-point. The primary objective of Phase II activities is to increase airflow from the pinch-point to the screening device, not allowing any seed to stall-out in the dislodgement chamber. The overall goals of Phase II is to capture 95% of the dislodged seed, reduce initial contact shatter to 3%, eliminate (0%) seed stalling-out in the dislodgement chamber and falling back through the pinch-point, eliminate (0%) seed carry-over the combing drum, increase captured seed purity to 99%, maintain seed loss in chaff out the screening device at <1%, and reduce seeds left on plants to 1%. If these goals are met, the Seedster will be the harvester of choice on small acreages, research plots and vineyard/orchard between-row production strips. APPROACH: In Phase I the 40" wide Test-Bed model Seedster was used for all shop and field trials. In Phase II, a new 60" wide Test-Bed will be constructed utilizing the same basic Seedster technology of a counter-rotating brush and combing drum that 'pluck' the seed from the targeted crop. Phase I performance standards were raised for Phase II. To meet the new standards design modifications will be tested. The present Seedster configuration relies primarily on the main 24" brush to create air-flow to transport dislodged seed from the pinch-point to the seed hopper. In Phase I it was found that the brush, no matter the bristle density, was capable of propelling only 59% (heavy stands) to 70% (moderate stands) of the dislodged seed to the seed hopper. The air assist brush, designed to supplement airflow and direct seed through the dislodgement chamber, was insufficient to propel dense, ovoid camelina seed. In Phase II a tangential flow fan will be tested to replace the air assist brush. Size and positioning will be optimized using a hot wire anemometer to map air flow. This objective for fan performance is to generate air at saltation velocity to propel all dislodged seed to the collection hopper. The expectation is that properly directed air flow will eliminate seed carry-over loss on the combing drum. When the size, shape and placement of components are near optimal the air flow pattern will be documented with digital High Speed Video for in-depth analysis and fine-tuning. The capability to easily adjust airflow for varying conditions and different species of seed will make Seedster technology more robust. Some loss of dislodged seed in Phase I resulted from the seed shatter when the main brush first came in contact with the plant inflorescences. Tests will be conducted to measure whether the increased airflow created by the tangential flow fan increases suction through the pinch-point. The new Test-Bed will permit placement of the combing drum in different positions. To improve seed dislodgement various brush bristle densities and various combing drum surfaces (increased static friction) will be tested. In Phase I a screening device consisting of an auger and a semi-cylindrical screen was designed and tested which screened the captured capsule halves and stems from the camelina seed. This device, utilizing a 9/64" round-hole screen, exceeded the targeted goal by capturing 97% pure seed in the seed hopper. In Phase II an 8/64" round-hole screen will be tested to increase seed purity to 99% without additional seed loss out the discharge of the device. If these new modifications are successful, they can be applied to all Seedster models ranging from the FH-SP (60" wide) to the FH-4 (over 14' wide)