Autonomous Agricultural Robot
An agricultural robot is a robot deployed for agricultural purposes. The main area of application of robots in agriculture today is at the harvesting stage. Emerging applications of robots or drones in agriculture include weed control, cloud seeding, planting seeds, harvesting, environmental monitoring and soil analysis. According to Verified Market Research, the agricultural robots market is expected to reach $11.58 billion by 2025.
General
Fruit picking robots, driverless tractor / sprayers, and sheep shearing robots are designed to replace human labor.
In most cases, a lot of factors have to be considered (e.g., the size
and color of the fruit to be picked) before the commencement of a task.
Robots can be used for other horticultural tasks such as pruning, weeding, spraying and monitoring.
Robots can also be used in livestock applications (livestock robotics) such as automatic milking,
washing and castrating. Robots like these have many benefits for the
agricultural industry, including a higher quality of fresh produce,
lower production costs, and a decreased need for manual labor. They can also be used to automate manual tasks, such as weed or bracken spraying, where the use of tractors and other manned vehicles is too dangerous for the operators.
Designs
Fieldwork Robot
The mechanical design consists of an end effector, manipulator, and gripper. Several factors must be considered in the design of the manipulator, including the task, economic efficiency, and required motions. The end effector influences the market value of the fruit and the gripper's design is based on the crop that is being harvested.
End effectors
An end effector in an agricultural robot is the device found at the end of the robotic arm,
used for various agricultural operations. Several different kinds of
end effectors have been developed. In an agricultural operation
involving grapes in Japan,
end effectors are used for harvesting, berry-thinning, spraying, and
bagging. Each was designed according to the nature of the task and the
shape and size of the target fruit. For instance, the end effectors used
for harvesting were designed to grasp, cut, and push the bunches of
grapes.
Berry thinning is another operation performed on the grapes, and is used to enhance the market value
of the grapes, increase the grapes' size, and facilitate the bunching
process. For berry thinning, an end effector consists of an upper,
middle, and lower part. The upper part has two plates and a rubber that
can open and close. The two plates compress the grapes to cut off the rachis
branches and extract the bunch of grapes. The middle part contains a
plate of needles, a compression spring, and another plate which has
holes spread across its surface. When the two plates compress, the
needles punch holes through the grapes. Next, the lower part has a
cutting device which can cut the bunch to standardize its length.
For spraying, the end effector consists of a spray nozzle that is
attached to a manipulator. In practice, producers want to ensure that
the chemical liquid is evenly distributed across the bunch. Thus, the
design allows for an even distribution of the chemical by making the
nozzle to move at a constant speed while keeping distance from the
target.
The final step in grape production is the bagging process. The
bagging end effector is designed with a bag feeder and two mechanical
fingers. In the bagging process, the bag feeder is composed of slits
which continuously supply bags to the fingers in an up and down motion.
While the bag is being fed to the fingers, two leaf springs that are
located on the upper end of the bag hold the bag open. The bags are
produced to contain the grapes in bunches. Once the bagging process is
complete, the fingers open and release the bag. This shuts the leaf
springs, which seals the bag and prevents it from opening again.
Gripper
The gripper
is a grasping device that is used for harvesting the target crop.
Design of the gripper is based on simplicity, low cost, and
effectiveness. Thus, the design usually consists of two mechanical
fingers that are able to move in synchrony
when performing their task. Specifics of the design depend on the task
that is being performed. For example, in a procedure that required
plants to be cut for harvesting, the gripper was equipped with a sharp
blade.
Manipulator
The manipulator allows the gripper
and end effector to navigate through their environment. The manipulator
consists of four-bar parallel links that maintain the gripper's
position and height. The manipulator also can utilize one, two, or three
pneumatic actuators. Pneumatic actuators are motors which produce linear and rotary motion by converting compressed air into energy.
The pneumatic actuator is the most effective actuator for agricultural
robots because of its high power-weight ratio. The most cost efficient
design for the manipulator is the single actuator configuration, yet
this is the least flexible option.
Development
The
first development of robotics in agriculture can be dated as early as
the 1920s, with research to incorporate automatic vehicle guidance into
agriculture beginning to take shape. This research led to the advancements between the 1950s and 60s of autonomous agricultural vehicles. The concept was not perfect however, with the vehicles still needing a cable system to guide their path.
Robots in agriculture continued to develop as technologies in other
sectors began to develop as well. It was not until the 1980s, following
the development of the computer, that machine vision guidance became possible.
Other developments over the years included the harvesting of oranges using a robot both in France and the US.
While robots have been incorporated in indoor industrial settings
for decades, outdoor robots for the use of agriculture are considered
more complex and difficult to develop.[citation needed]
This is due to concerns over safety, but also over the complexity of
picking crops subject to different environmental factors and
unpredictability.
Demand in the market
There
are concerns over the amount of labor the agricultural sector needs.
With an aging population, Japan is unable to meet the demands of the
agricultural labor market.
Similarly, the United States currently depends on a large number of
immigrant workers, but between the decrease in seasonal farmworkers and
increased efforts to stop immigration by the government, they too are
unable to meet the demand. Businesses are often forced to let crops rot due to an inability to pick them all by the end of the season. Additionally, there are concerns over the growing population that will need to be fed over the next years.
Because of this, there is a large desire to improve agricultural
machinery to make it more cost efficient and viable for continued use.
Current applications and trends
Much
of the current research continues to work towards autonomous
agricultural vehicles. This research is based on the advancements made
in driver-assist systems and self-driving cars.
While robots have already been incorporated in many areas of
agricultural farm work, they are still largely missing in the harvest of
various crops. This has started to change as companies begin to develop
robots that complete more specific tasks on the farm. The biggest
concern over robots harvesting crops comes from harvesting soft crops
such as strawberries which can easily be damaged or missed entirely.
Despite these concerns, progress in this area is being made. According
to Gary Wishnatzki, the co-founder of Harvest Croo Robotics, one of
their strawberry pickers currently being tested in Florida can "pick a
25-acre field in just three days and replace a crew of about 30 farm
workers". Similar progress is being made in harvesting apples, grapes, and other crops.
Another goal being set by agricultural companies involves the collection of data. There are rising concerns over the growing population and the decreasing labor available to feed them. Data collection is being developed as a way to increase productivity on farms.
AgriData is currently developing new technology to do just this and
help farmers better determine the best time to harvest their crops by
scanning fruit trees.
Applications
Robots
have many fields of application in agriculture. Some examples and
prototypes of robots include the Merlin Robot Milker, Rosphere, Harvest Automation, Orange Harvester, lettuce bot,
and weeder. One case of a large scale use of robots in farming is the
milk bot. It is widespread among British dairy farms because of its
efficiency and nonrequirement to move. According to David Gardner (chief
executive of the Royal Agricultural Society of England), a robot can
complete a complicated task if its repetitive and the robot is allowed
to sit in a single place. Furthermore, robots that work on repetitive
tasks (e.g. milking) fulfill their role to a consistent and particular
standard.
Another field of application is horticulture. One horticultural application is the development of RV100 by Harvest Automation Inc. RV 100 is designed to transport potted plants in a greenhouse
or outdoor setting. The functions of RV100 in handling and organizing
potted plants include spacing capabilities, collection, and
consolidation. The benefits of using RV100 for this task include high
placement accuracy, autonomous outdoor and indoor function, and reduced production costs.
Examples
- Thorvald - an autonomous modular multi-purpose agricultural robot developed by Saga Robotics.
- Vinobot and Vinoculer
- LSU's AgBot
- Harvest Automation is a company founded by former iRobot employees to develop robots for greenhouses
- Root AI has made a tomato-picking robot for use in greenhouses
- Strawberry picking robot from Robotic Harvesting and Agrobot.
- Small Robot Company developed a range of small agricultural robots, each one being focused on a particular task (weeding, spraying, drilling holes, ...) and controlled by an AI system
- ecoRobotix has made a solar-powered weeding and spraying robot
- Blue River Technology has developed a farm implement for a tractor which only sprays plants that require spraying, reducing herbicide use by 90%
- Casmobot next generation slope mower
- Fieldrobot Event is a competition in mobile agricultural robotics
- HortiBot - A Plant Nursing Robot,
- Lettuce Bot - Organic Weed Elimination and Thinning of Lettuce
- Rice planting robot developed by the Japanese National Agricultural Research Centre
- ROS Agriculture - Open source software for agricultural robots using the Robot Operating System.
- The IBEX autonomous weed spraying robot for extreme terrain, under development
- FarmBot, Open Source CNC Farming
- VAE, under development by an argentinean ag-tech startup, aims to become a universal platform for multiple agricultural applications, from precision spraying to livestock handling.
- ACFR RIPPA: for spot spraying
- ACFR SwagBot; for livestock monitoring
- ACFR Digital Farmhand: for spraying, weeding and seeding
