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Automated control systems – An agricultural example


Music So, automated systems allow the crop to be
grown while the grower is not present. So, the automated system is there to nurture the crop,
to look after the crop 24 hours a day, 7 days a week, 365 days a year. A good grower could do it himself if he was
there all the time but with an automated system the system itself will continue to do his job
throughout the whole period whether he’s there or not. So, it all started in Roman times when
the Romans actually developed the first protected cropping systems. Then during the Joseon period or Joseon Dynasty
I should say in the 15th Century the first actual greenhouses were developed. These actually included very simple climate control
like heating and cooling but the newer developments were not until after Second World War
mostly in the Netherlands where the first greenhouses were used to grow crops all year round. These greenhouses included heating using
simple heaters to start with with kerosene and later with gas heaters which also gave CO2. And then in the mid 70s the first actual controllers
came on the market. These controllers were analogue controllers,
analogue meaning they contained dials and they had what’s called VU metres like you
might see in your old grandad’s radio. And the dials would show you the temperature
and the actual knobs you would use to set your temperature etcetera. Then in the late 70s the first actual controllers
came on the market which were digital. So, these controllers actually had memory
and allowed you to set settings via a keypad. The graphical user interfaces didn’t happen
until the early 90s with the advent of PCs which allowed a user interface with
actual graphics on it. So, the computer knows what to do via a whole
host of sensors that are connected to the computer. Now, these sensors include a weather station
to measure wind speed, wind direction, rain, temperature, humidity but also include sensors
inside a greenhouse which are temperature humidity sensors, hot temperature sensors,
crop sensors like substrate moisture sensors, substrate temperature sensors and also sensors
that are used in the water room like flow sensors, the pH of the water is measured there
and EC of the water which is an indication of how much fertiliser is in the water. So, with this information the controller can
make decisions via the algorithms that are programmed into the controller. So, the climate systems that you find in a
modern greenhouse include ventilation which have the vents that go up and down
which provide cooling. Screens which retract and employ by the user,
via the automated system to provide shading in case it gets too hot, also to provide energy
reduction at night for example and blackout systems which allow the system
to actually blackout a compartment to shorten the day and this is for day length sensitive crops. Also, in a greenhouse you’ll find lighting
of course to extend the day and also to provide energy if the Sun’s not giving enough. You’ll also find heating which is done by
hot water pipes which are circulating hot water through them and controlled by
pumps and valves. Air circulation fans will make sure that
the environment within the greenhouse is homogenous at all times. And pad and fan systems will allow the system
to introduce air from outside and cool it as it enters the greenhouse, cool the air,
there by cooling the house and also raising the humidity. More recent developments include cooling systems
which use either cooled water or glycol through heat exchanges to both lower the temperature
but also lower the humidity because once the air is cooled below the dew point, the water
will actually drop out of the air and it allows you to control humidity in areas where the
humidity is very high. So, user interfacing of the control systems,
well at the end of the day the control is done by a controller and a controller works
in bits and bytes and it’s just doing its job. Now, users generally don’t understand bits
and bytes and we want to make the system usable for the user so we develop a user interface. So, this will include a PC which will have
generally text space settings and read outs by text but also includes graphical user interface. So, this is where there’ll be either a shot
of the greenhouse or an aerial photograph over which is overlayed various settings and
readings that are achieved within that greenhouse. Other developments these days that we’ve been
working on at Priva are for example the app which allows users to remotely both monitor
and control their greenhouses from anywhere in the world either one site or
multiple sites, so data collection. Now, from day 1 when a system is first set up
data is being collected by the system. All systems that are supplied include
data collection which is continuously collected from the day it’s installed. And what the users do is look at their data
on a daily basis to make decisions on what they should do with settings and what they
should do with the crop etcetera. Managers on the other hand will look at their data
and make decisions as to when they should be harvesting, how much they
might be harvesting. And on the other hand the company owners or
upper management will make decisions on what crops to grow and these sort of things. Data can be analysed in various ways and these
days with the advent of Cloud systems and Priva is one of them we are looking at ways
we can actually access the data and also analyse the data through the Cloud so the data can
be used and analysed by the various companies that own the data. At the end of the day what’s also important
is data security and any company, us included will always ensure that the data belongs to
the user or to the company that’s bought the system and cannot in anyway be accessed by
any employee of Priva in anyway whatsoever. One exciting development is the advent of robotics. So, there’s various companies working on
various types of robots including Priva, we’re currently developing a robot which
autonomously picks tomato leaves. Other types of robots under development are
scouting robots and these robots scout by the pests or diseases autonomously
and then report back to a central system so that the user and managers can see where
various hotspots are within their crop and also then do targeted spraying where necessary. Other types of robots that are under development
are for example picking robots. These robots will then autonomously pick the fruit
and other types of robots are spraying robots, they’re already being used but they’ll
get smarter and smarter as well. Then there are Cloud developments, now everyone
is probably aware of the Cloud but we’re only just at the early stages of all
the possibilities in the Cloud. For starters there’s remote access to various systems,
there’s also data storage in the Cloud and data analysis in the Cloud. There are alarm systems that are based in
the Cloud and there’s various other services which will come online as time goes by. Other things that are being worked on
at the moment are things like the sustainable urban delta and this is a concept where greenhouses,
living areas, industrial areas, commercial areas are fully integrated. And the idea behind it is there is a huge
movement towards urbanisation worldwide. So, the trend is we’re going to have larger
and larger cities. For example Shanghai is a city of 27 million people. And what happens is people are all congregating
in these large cities but they also need to eat of course. By combining the resources of water, energy,
light, etcetera we can be much, much more efficient in terms of where we produce food
and where it gets consumed.

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