In 2019, 2nd Sight was commissioned by the Washington Hop Commission and supported by the USDA Specialty Crop Block Grant Program (SCBGP) and matching grants from the Spokane Health Sciences and Services Authority (HSSA) to design and build the MAV, or "Multifunctional Agriculture Vehicle." This innovative new piece of farm equipment will support modular attachments designed to automate several labor-intensive processes required in growing hops and other specialty crops.
Multifunctional Agriculture Vehicle used for general field work as a mobile platform with elevated platform capabilities.
Automated tying mechanism to attach twine (PLA) to a wire.
Automated staking mechanisms to drive twine ends into the ground.
Automated top cutting mechanisms to cut hops bine and twine.
One of our long-time customers grows apples, cherries, grapes, blueberries, and hops. This farm asked if we could design a way to automate the stringing and staking of hops because it is a growing problem in the industry. After speaking with a number of hops growers in WA, ID, and OR, we found that EVERY grower listed this project as their highest priority to improve hop production. This project was funded by the Washington Hop Commission, the Washington State Specialty Crop Block Grant Program, the Spokane County HSSA, and by our company.
Stringing or twining is the process of affixing a length of twine to the hop trellis. This twine is typically about 21 ft. in length and extends to the ground from the 18 ft-high trellis cable. Staking is the operation of securing the twine to the ground near the hop plant. This is typically done by driving a “W” clip into the ground while capturing a loop of the twine.
The MAV stands for, "Multifunctional Agricultural Vehicle." The biggest issue in bringing automation to farming, is that much of the equipment is only needed for a very short time during the growing season. Thus, any automation would have to pay for itself quickly. Since automation is quite expensive to build, it is critical to evaluate the return on investment (ROI) of a new system. The MAV was designed to automate several operations on the farm so that implements can be quickly attached and removed. For example, the Twiner and Staker modules can be added in the early spring for stringing hops. These implements can then be removed and replaced with the Top Cutters for harvesting. At any time, the unit can be used as an elevated platform for work on trellis systems. In general, growers should be able to use this system nearly half the year which helps justify the investment. In the future, we plan to add additional attachments such as a hop combine and chopper so that the hops bines do not have to be removed from the field but can be processed immediately after cutting.
We accomplished Phase 1 of our plan by completing the automation in our facility. We completed Phase 2 in October 2021 by building the mobile platform (MAV), mounting the automation, and performing trials with the Twiner system. After several iterations of the Twiner mechanism, we have a knotter that meets all our specifications. Phase 3 is the development of the Staker. This project is currently under development and will be completed by 2024. Phase 4 will be the build and field testing of one production-ready MAV. This phase will be completed during the spring of 2025.
No, unfortunately coir twine is not suitable to run through automation. After initial evaluation, coir was too stiff and inconsistent. Fortunately, we have found other twine materials that work very well both in the automation and in growing hops. MAV with Twiner and Top Cutter modules will be available.
Currently, we have approved PLA twine from two different vendors and are working on jute twine as well. PLA stands for polylactic acid and is biodegradable plastic made from corn. This is a material that is very strong and maintains its strength throughout the growing season. Working with our grower partners, we have shown that PLA twine has worked with both adult and baby plants on every variety that has been tested (over 20 different varieties).
PLA is comparable in cost to coir twine but has the advantage that it is much smaller in diameter so that the MAV can carry a lot more onboard. Jute twine is slightly more expensive than either coir or PLA and will only be used as a backup should there ever be an issue sourcing PLA.
The MAV has two speeds. In high speed it can travel from 0-6 mph and in low speed it can travel from 0-0.35 mph. The low speed is determined by how fast the machine can twine. All hop yards are on a 56 ft. pole to pole spacing on a diamond pattern with rows that are either 12 ft. or 14ft. in width. This means that trellis support cables are located every 28 ft. Each row typically contains 16 twines. Twines are placed 1.75 ft. from the pole, then every 3.5 ft. with 16 twines between poles. This means that the machine must be able to tie a twine 1.75 ft. from each pole and 1.75 f.t on either side of the support cables. If the MAV were to travel at 0.5 mph, we would only have two seconds to tie the knot to the trellis cable before we ran into the support cable and we simply cannot tie that quickly. At a speed of 0.3 mph, we have 3.8 seconds to tie the knot which is feasible.
The MAV was designed to twine and stake 250 acres in six weeks working 20 hours per day. It will twine one acre every 3.36 hours with just one person.
At a minimum, the MAV holds enough twine onboard for one 10-hour shift. We may be able to hold enough twine for a full 20-hour shift.
Yes, the MAV was designed with both front and rear wheel steering. The vehicle can turn tight corners and even “crabwalk” between poles.
Probably not. The wheels are very wide, and the vehicle has four-wheel drive. There is an option to put treads on the system so that you could have a tracked vehicle if soft soil is a problem.
The machine was designed to be safe for operation in fields with up to a 5% grade. When the machine is on a 0-3% grade, the tilt indicator light is green. If the grade exceeds 3% but is less than 5%, the indicator light goes from green to yellow. If the grade exceeds 5%, the machine will halt until the operator lowers the operator basket.
The projected cost of the MAV with Twiner and Staker attachments is in the $250,000 to $300,000 range. When used for top cutting and as an elevated platform for trellis work, the ROI on this equipment is only a couple of years.
Yes, you will need to sign up for our Service, Support, Maintenance, and Twine Agreement. This is a five-year contract that includes service, support, maintenance, and enough twine for 250 acres for a fixed price. This guarantees your costs for a five-year period so that you do not have to worry about the machine maintenance. Except for normal wear and tear or negligence, any problems with the machine are covered by this contract
As per our grower partners, the average cost to twine 250 acres is $147,086. This includes labor, twine, and miscellaneous costs such as preparing the twine and stringing loses. This cost does not include L&I costs or other labor-related expenses which should be eliminated with this automation. The value of this machine for top cutting purposes is placed at $35/hr. for 360 hours and for elevated platform work at $35/hr. for 160 hours. Based on these numbers, the expected minimum yearly value for this machine will be approximately $164,700 per year.
Currently, capital equipment farm loans are advertised at 3% over a five-year period. For a $250,000 loan, this yields an annual rate of $53,906 in principle and interest payments. When combined with the cost of the Twine/Service/Support contract, the first-year cost for this automation is $164,156, slightly better than breakeven for the grower in the first year of purchase. If labor costs rise at 8% per year and twine cost rises by 3% per year, this automation will save the average grower almost $450,000 over a 10-year period.