1. Porthcawl Comprehensive School
Lafarge Tarmac
“SMART
Early
Warning
System”
Team: Andrew Philips (Team Leader)
Jack Bevan
Curtis Naughton
Jasmeen Dawes
Tom Parsons
Keiren Waring
Aneurin Weale
Matthew Williams
Engineer: Mr Phil Jones
Teacher: Mr Richard Lawson
March 2014

2. Porthcawl
Comprehensive
School
March,
2014
2
Contents
Contents..................................................................................................................................... 1
Executive Summary................................................................................................................... 3
Introduction ............................................................................................................................... 4
Analysis of Problem .................................................................................................................. 5
Research into Existing Technologies ........................................................................................ 6
Capacitance
Sensing
...........................................................................................................................
6
Analog
Devices
...................................................................................................................................
6
Ultrasonic
range
finder
......................................................................................................................
7
Data Processing ......................................................................................................................... 8
Procedure................................................................................................................................. 11
Initial
Meeting
..................................................................................................................................
11
Research
...........................................................................................................................................
11
About
Tarmac
...................................................................................................................................
12
Site
visit
............................................................................................................................................
13
Final
Solution
....................................................................................................................................
16
Design Development ............................................................................................................... 17
Hardware
..........................................................................................................................................
17
Python Scripts.......................................................................................................................... 19
Prototype
Testing
.............................................................................................................................
24
Results, Discussion and Evaluation......................................................................................... 26
Environmental
Benefits
....................................................................................................................
26
Development
Costs
..........................................................................................................................
27
Cost
Benefits
....................................................................................................................................
28
Health
and
Safety
.............................................................................................................................
28
Wider
Scope
of
Project
.....................................................................................................................
29
Conclusion............................................................................................................................... 30
Appendix ................................................................................................................................. 31

3. Porthcawl
Comprehensive
School
March,
2014
3
Executive
Summary
In
the
world
of
business,
orders
must
be
fulfilled
in
a
timely,
efficient
and
cost
effective
manner.
This
is
equally
true
in
the
field
of
engineering.
Business
success
can
be
me
made
or
broken
on
the
strength
of
a
having
a
company
reputation
of
making
deliveries
on
time.
If
orders
are
fulfilled
quickly
then
costs
can
also
be
controlled
and
savings
can
be
passed
on
to
customers.
This
project
will
investigate
ways
in
which
the
manufacture
and
delivery
of
asphalt
can
be
maintained
and
made
robust
to
ensure
customer
satisfaction.
In
Asphalt
manufacture,
lime
stone
is
quarried,
crushed
and
mixed
with
Bitumen
and
stone
dust
to
make
a
solid
and
robust
construction
material
for
the
laying
of
roads
and
motorways.
In
the
case
of
Lafarge
Tarmac
at
Cornelly,
the
stone
is
quarried
on
site.
The
bitumen
it
is
mixed
with
is
supplied
from
a
refinery
in
Birkenhead
and
stored
in
four
50,000
litre
tanks.
The
stone
is
mixed
with
the
bitumen
as
the
product
is
required.
Clearly,
the
supply
of
stone
is
in
abundance
thanks
to
the
onsite
quarry.
However,
the
bitumen
supply
must
be
more
closely
monitored
to
ensure
a
constant
amount
is
on
site
to
meet
the
orders
received.
Currently,
this
level
is
monitored
by
engineers
on
site.
This
is
a
laborious
and
time
consuming
process
which
takes
manpower
that
could
be
usefully
employed
elsewhere.
A
better
solution
would
be
an
automatic
system
that
could
alert
on
site
engineers
that
supplies
are
being
depleted
so
orders
could
be
made
on
time.
This
would
ideally
take
the
form
of
an
alert
being
sent
to
the
engineers
wherever
they
are
instead
of
valuable
staff
being
limited
to
a
small
radius
around
the
tanks.
This
project
will
outline
the
design,
prototyping
and
testing
of
a
low
cost
automatic
level
warning
system
that
will
notify
staff
of
low
bitumen
levels
via
SMS
text
message.
This
will
aim
to
deliver
improvements
in
efficiency,
cost
saving
and
will
also
provide
environmental
benefits
through
a
small,
low
cost
and
easily
implemented
unit.

4. Porthcawl
Comprehensive
School
March,
2014
4
Introduction
In
order
to
maximise
cost
savings
and
ensure
that
highest
customer
service
levels
are
maintained
on
the
company’s
Asphalt
plants,
“full
loads”
of
bitumen
must
be
ordered
and
delivered
on
time.
Predicting
how
much
to
order
and
when
is
currently
an
art
form
and
needs
to
be
turned
into
a
science
if
costly
“part
loads”
are
to
be
eliminated.
Reducing
the
number
of
part
loads
is
a
key
performance
indicator
for
the
asphalt
business
and
this
system
will
help
reduce
cost
and
improve
safety
at
our
sites.
The
project
aim
was
to
design
and
build
a
working
prototype
system
to
monitor
and
predict
the
usage
of
bitumen
in
bitumen
storage
tanks
such
that
an
automated
SMS
text
message
will
be
generated
and
sent
to
the
site
manager
(or
his/her
deputy)
alerting
him/her
of
the
need
to
re-­‐order
a
“full
load”
of
bitumen
on
a
given
date.
In
addition,
a
monthly
spreadsheet
will
also
be
generated
from
that
system
showing,
bitumen
ordered,
dates
and
times
plus
cost
savings
as
compared
to
historical
data
in
the
previous
financial
year
which
include
costly
and
unwanted
part
loads.
Additional
features
in
the
software
and
reporting
will
also
be
required
and
these
will
be
discussed
with
the
team
throughout
the
project
execution.

5. Porthcawl
Comprehensive
School
March,
2014
5
Analysis
of
Problem
Scope:
To
design
and
manufacture
a
scaled
working
system
to
carry
out
the
following
functions:
1. Monitor
fluid
level
in
a
vertical
cylindrical
tank
and
predict
the
usage
to
a
pre-­‐determined
level.
2. At
that
pre-­‐determined
level,
an
alarm
will
be
triggered
sending
a
signal
to
a
PC
which
in
turn
will
send
out
an
SMS
text
message
to
the
site
managers’
mobile
phone.
The
message
will
be
sent
only
between
the
hours
of
06:00am
and
18:00pm,
Mon-­‐Sat,
50
weeks
p.a.
The
message
will
advise
the
manager
to
re-­‐order
a
full
load
of
fluid
(bitumen)to
maintain
stock
levels,
protect
plant
availability
and
customer
service
levels.
3. In
any
event,
a
text
message
will
be
sent
if
no
bitumen
has
been
ordered
within
any
single
24
day
period
as
a
quality
requirement
to
refresh
the
stock
4. A
monthly
spreadsheet
will
also
be
required
(in
Excel
format)
illustrating
how
many
loads
were
flagged
up
via
text
message
during
any
particular
calendar
month
showing
the
total
cost
of
those
loads
both
in
month
and
cumulative
timescales.
5. The
same
spreadsheet
will
also
be
required
to
show
the
cost
saving
of
not
having
to
order
part
loads
in
the
month/year
(using
2012
historical
data
for
reference).
4No.Bitumen
Tanks
50,000L
Capacity
Each
To
Asphalt
Plant
Full
Refill
Empty
Level
indication
to
PC
SMS
text
message
to
manager
to
re-­‐order
bitumen
(At
pre-­‐ determined
level)
Text
message Produce
monthly
Spreadsheet
showing
savings
EESW
2013

6. Porthcawl
Comprehensive
School
March,
2014
6
Research
into
Existing
Technologies
Capacitance
Sensing
Sensor
Technics
With
over
20
years
of
extensive
experience
in
the
development
and
manufacture
of
unique
optical
and
MEMS
sensor
solutions,
our
brand
portfolio
includes
strong
and
highly
specialised
brands.
We
serve
custom
development
and
manufacturing
at
14
sites
around
the
world.
Analog
Devices
Analog
Devices
offers
the
world’s
first
high-­‐precision,
fully
integrated
Capacitance-­‐to-­‐Digital
Converters
(CDC),
that
address
the
complex
and
difficult
signal
processing
challenges
of
direct
capacitance-­‐to-­‐digital
conversion.
The
award-­‐winning
Capacitance-­‐to-­‐Digital
Converter
(CDC)
technology
enables
high
accuracy
capacitance
sensing
for
Industrial,
Automotive,
and
Consumer
applications.
http://www.analog.com/en/analog-­‐to-­‐digital-­‐converters/capacitance-­‐to-­‐digital-­‐
converters/products/index.html?gclid=CIGd2LS9yboCFfHItAodDXoAcw#Capacitive_to_Digi
tal_Converters

7. Porthcawl
Comprehensive
School
March,
2014
7
Ultrasonic
range
finder
Ultrasonic
sensors
(also
known
as
transceivers
when
they
both
send
and
receive,
but
more
generally
called
transducers)
work
on
a
principle
similar
to
radar
or
sonar
which
evaluates
attributes
of
a
target
by
interpreting
the
echoes
from
radio
or
sound
waves
respectively.
Ultrasonic
sensors
generate
high
frequency
sound
waves
and
evaluate
the
echo
which
is
received
back
by
the
sensor.
Sensors
calculate
the
time
interval
between
sending
the
signal
and
receiving
the
echo
to
determine
the
distance
to
an
object.
This
technology
can
be
used
for
measuring
wind
speed
and
direction
(anemometer),
tank
or
channel
level,
and
speed
through
air
or
water.
For
measuring
speed
or
direction
a
device
uses
multiple
detectors
and
calculates
the
speed
from
the
relative
distances
to
particulates
in
the
air
or
water.
To
measure
tank
or
channel
level,
the
sensor
measures
the
distance
to
the
surface
of
the
fluid.
Further
applications
include:
humidifiers,
sonar,
medical
ultrasonography,
burglar
alarms
and
non-­‐destructive
testing. Systems
typically
use
a
transducer
which
generates
sound
waves
in
the
ultrasonic
range,
above
18,000
hertz,
by
turning
electrical
energy
into
sound,
then
upon
receiving
the
echo
turn
the
sound
waves
into
electrical
energy
which
can
be
measured
and
displayed.
The
technology
is
limited
by
the
shapes
of
surfaces
and
the
density
or
consistency
of
the
material.
Foam,
in
particular,
can
distort
surface
level
readings

8. Porthcawl
Comprehensive
School
March,
2014
8
Data
Processing
i) Database
to
look
up/
convert
raw
data
into
usable
data
Polyspot
-­‐
PolySpot's
information
management
solutions
can
be
used
to
extract
and
enrich
raw
data,
so
that
these
data
can
be
used
by
and
distributed
to
users.
Universal
and
long-­‐term
connectivity
-­‐
Connectivity
with
the
various
applications
that
a
company
uses
is
essential
for
raw
data
collection.
With
a
library
of
over
100
application
connectors,
‘PolySpot
Silo
Breaker’
can
easily
be
connected
to
the
majority
of
market-­‐
standard
content
(DMS,
CMS,
WCMS,
DBMS,
web,
RSS),
guaranteeing
long-­‐term
access
from
a
single
point
to
all
of
a
company's
applications.
From
raw
data
to
enriched
information
-­‐
Freshly-­‐produced,
out-­‐of-­‐context
data
is
neither
useful
nor
meaningful.
PolySpot
has
developed
conversion
and
semantic
enrichment
modules
to
standardise
and
contextualise
raw
data
to
produce
information
that
can

9. Porthcawl
Comprehensive
School
March,
2014
9
instantly
be
used
by
a
range
of
different
search
services.
In
order
to
combine
high
information
availability
and
maximum
indexing
versatility,
PolySpot
has
developed
a
unique
architecture,
capable
of
managing
a
variety
of
processes
in
both
synchronous
and
asynchronous
mode.
Shared
and
distributed
information
-­‐
Enriched
information
is
distributed
via
a
range
of
different
search
services,
each
of
which
is
capable
of
providing
users
with
all
available
information
from
a
single
interface.
PolySpot's
enterprise
search
applications
can
be
adapted
to
suit
business-­‐specific
requirements,
with
unrivalled
configuration
and
display
options
(simple
search
interface
configuration,
relevance
fine-­‐tuning,
specific
settings
based
on
the
user's
profile
and
context)
and
intelligent
searching
and
browsing
functions
(auto-­‐
complete,
spelling
suggestion,
thesaurus/ontology
integration,
property-­‐based
browsing,
multi-­‐view
management,
alerts,
collaborative
functions,
etc.).
ii) Automatically
generate
a
text
based
on
information
Text
Local
-­‐
Easily
text
important
information,
offers
&
alerts.
Attach
pictures,
files,
web-­‐
links
&
surveys.
Text
local
help
over
102,383
businesses
send
up
to
40
million
messages
per
month.
Over
the
last
seven
years,
Textlocal
have
been
at
the
forefront
of
business
mobile
messaging.
Our
in-­‐house,
award
winning,
technical
team
like
nothing
better
than
to
innovate
and
build
tools
optimized
for
delivery
on
mobile
phones
that
meet
real
business
needs.
We
deal
with
businesses
every
day.
We
know
the
challenges
you
face
and
we
understand
your
needs.
Our
emphasis
is
on
efficiency,
integration
and
ease
of
use.
Our
Messenger
platform
has
been
built
with
this
in
mind,
along
with
some
really
useful
added
extras
such
as
tracking,
surveys,
attachments,
ticketing,
analytics,
campaign
management
tools
and
much
more.
Our
ethos
encompasses
a
complete
dedication
to
exceeding
customer
expectations,
and
this
has
been
highly
commended
by
industry
experts.
The
awards
have
just
kept
coming.
We
have
been
listed
as
a
Media
Momentum
top
20
fastest
growing
digital
agency
across
Europe
for
the
last
three
years,
won
a
Chamber
Business
Award
for
innovation,
a
DMA
Honours
award
for
marketing
Innovation
and
also
shortlisted
for
the
best
marketing
services
company.
This
adds
to
our
collection
including
Global
Messaging
Award
for
our
exceptional
messaging
infrastructure,
and
Digital
and
Media
Entrepreneurs
of
the
year.
Our
ever
growing
staff
base
is
made
up
of
passionate,
dedicated
people
who
believe
completely
in
how
Textlocal
can
revolutionise
the
communication
structure
of
any
business.
As
the
awards
keep
coming
in
and
our
customers
remain
extremely
satisfied,
we
know
Textlocal
is
an
exciting
company
to
be
involved
with
on
any
level.

10. Porthcawl
Comprehensive
School
March,
2014
10
Twilio
SMS
-­‐
Send
&
receive
SMS
with
twilio
messaging
Global
Text
Messaging
API
-­‐
Build
apps
that
send
and
receive
SMS
using
phone
numbers
and
short
codes,
perfect
for
businesses
and
organisations.
The
API
enables
users
to
communicate
with
their
app
and
send
messages
when
they
wish.
Build
Intelligent
Communications
-­‐
Twilio
lets
you
use
standard
web
languages
to
build
SMS
and
voice
applications.
We’re
connected
to
carrier
networks
globally
and
expose
them
to
you
via
a
clean,
powerful
web
API.
So
bring
your
favorite
programming
language,
a
web
server,
and
build
the
next
generation
of
communications
with
us.
Cloud
Powered
-­‐
We’re
built
in
the
cloud.
Our
API
is
always
available,
continuously
upgraded
and
auto-­‐scales
to
meet
your
needs.
When
you
move
your
communications
to
the
cloud,
there
are
no
tricky
VPNs
to
configure
or
SMPP
binds
to
manage.
Just
send
us
your
message
via
HTTP,
and
we’ll
deliver
it
anywhere
in
the
world.

11. Porthcawl
Comprehensive
School
March,
2014
11
Procedure
Initial
Meeting
We
first
met
Mr
Phil
Jones
at
the
Introduction
meeting
in
Bridgend
where
he
announced
himself
as
our
Engineer.
Phil
introduced
himself
and
the
company
that
he
was
involved
in
which
was
‘Lafarge
Tarmac’.
He
then
went
on
to
explain
in
more
detail
what
kind
of
company
Lafarge
was
and
the
sort
of
work
that
they
are
involved
in.
After
explaining
some
details
about
the
company,
Phil
moved
onto
the
task
in
hand
which
was
the
project
to
be
given
to
and
developed
by
our
team.
He
gave
us
the
definition
of
the
problem
and
helped
us
to
visualise
this
by
giving
us
information
sheets
and
diagrams.
Phil
then
explained
in
more
detail
the
type
of
solution
they
were
looking
for
and
why
this
solution
was
required.
We
then
began
to
discuss
the
problem,
thinking
of
and
writing
down
key
features
that
the
possible
solution
must
include
and
how
we
could
go
about
developing
these
solutions.
After
a
lengthy
discussion,
we
felt
quite
confident
on
the
project
and
thought
that
a
suitable
solution
was
quite
possible
and
therefore
were
looking
forward
to
working
with
Phil
and
Lafarge.
Since
the
initial
discussion,
we
have
kept
in
touch
with
Phil
regularly
with
him
attending
our
meetings
at
least
once
a
month.
With
the
purpose
of
these
visits
being
to
see
the
progress
and
development
of
the
project
first-­‐hand
and
in
order
to
give
us
any
data,
information
or
advice
that
we
may
have
requested
in
order
to
help
with
the
completion
of
the
task.
Research
into
level
monitoring
Research
Through
the
course
of
seeking
the
best
solution
for
the
project,
a
large
amount
of
research
was
conducted
by
the
team
members
into
the
different
types
of
systems
currently
in
use
for
measuring
levels
of
fluids,
sending
text
messages
and
processing
data.
Many
of
these
were
ruled
out
as
either
too
expensive
or
too
difficult
to
make.

12. Porthcawl
Comprehensive
School
March,
2014
12
About
Tarmac
Lafarge
Tarmac
is
the
UK's
leading
supplier
of
aggregates
and
asphalt.
They
combine
industry-­‐leading
innovation
with
an
unrivalled
supply
and
distribution
network
that
includes
over
100
quarries,
70
dedicated
asphalt
plants
and
70
recycling
operations.
Their
products
meet
the
highest
standards
of
sustainability
and
performance,
as
you
would
expect
from
a
market
leader.
They
are
responsibly
sourced
and
certified
to
BES
6001.
Their
range
of
'Ultimate'
aggregate
and
asphalt
solutions
have
been
designed
to
meet
the
daily
challenges
faced
by
construction
professionals.
These
specialist
solutions
help
their
customers
deliver
outstanding
results
in
shorter
timescales,
even
when
faced
with
challenging
requirements
or
difficult
site
conditions.
Asphalt
(also
known
as
bitumen),
is
a
sticky,
black
and
highly
viscous
liquid
or
semi-­‐solid
form
of
petroleum.
It
may
be
found
in
natural
deposits
or
may
be
a
refined
product;
it
is
a
substance
classed
as
a
pitch.
Until
the
20th
century,
the
term
asphaltum
was
also
used.
The
primary
use
(70%)
of
asphalt/bitumen
is
in
road
construction,
where
it
is
used
as
the
glue
or
binder
mixed
with
aggregate
particles
to
create
asphalt
concrete.
Its
other
main
uses
are
for
bituminous
waterproofing
products,
including
production
of
roofing
felt
and
for
sealing
flat
roofs.
The
terms
asphalt
and
bitumen
are
often
used
interchangeably
to
mean
both
natural
and
manufactured
forms
of
the
substance.
In
American
English,
asphalt
(or
asphalt
cement)
is
the
carefully
refined
residue
from
the
distillation
process
of
selected
crude
oils.
Outside
the
United
States,
the
product
is
often
called
bitumen.
Geological
terminology
often
prefers
the
term
bitumen.
Common
usage
often
refers
to
various
forms
of
asphalt/bitumen
as
"tar",
such
as
at
the
La
Brea
Tar
Pits.
Another
term,
mostly
archaic,
refers
to
asphalt/bitumen
as
"pitch".
The
pitch
used
in
this
mixture
is
sometimes
found
in
natural
deposits
but
usually
made
by
the
distillation
of
crude
oil.
Naturally
occurring
asphalt/bitumen
is
sometimes
specified
by
the
term
"crude
bitumen".
Its
viscosity
is
similar
to
that
of
cold
molasses
while
the
material
obtained
from
the
fractional
distillation
of
crude
oil
[boiling
at
525
°C
(977
°F)
is
sometimes
referred
to
as
"refined
bitumen".

13. Porthcawl
Comprehensive
School
March,
2014
13
At
the
site,
we
were
briefed
about
the
company’s
health
and
safety
guide,
which
is
a
prime
concern
of
Lafarge
Tarmac.
Lafarge
Tarmac
is
keen
to
play
an
active
part
in
the
community
and
encourage
schools
and
other
interested
groups
to
visit
their
sites
and
gain
firsthand
knowledge
of
their
industry.
However,
quarries
and
other
areas
such
as
asphalt
plants
and
recycling
depots
can
be
dangerous.
During
the
visit,
the
group
had
to
stay
together
under
the
supervision
of
a
guide
provided
by
the
company.
Site
visit
We
were
invited
to
visit
the
Quarry
to
see
the
Bitumen
tanks
in
their
location
and
to
see
the
kind
of
environment
in
which
they
the
system
would
be
installed.
This
was
a
potentially
hazardous
environment
which
meant
we
had
to
have
a
safety
lesson
and
then
were
issued
with
protective
clothing
and
equipment.

14. Porthcawl
Comprehensive
School
March,
2014
14
When
we
went
out
into
the
quarry,
we
were
taken
to
the
Bitumen
tanks
in
the
minibus
with
a
safety
car
escort
and
were
shown
how
the
bitumen
was
loaded
in
to
the
tanks
as
there
was
a
delivery
taking
place
at
the
time.

15. Porthcawl
Comprehensive
School
March,
2014
15
We
were
then
taken
up
to
the
top
of
the
10m
tall
tanks
to
see
where
the
sensor
could
be
installed.
From
here
we
were
taken
around
the
entire
quarry
site
and
shown
how
Lafarge
Tarmac
first
quarries
the
limestone,
treats
the
stone
and
finally
turns
it
into
asphalt
that
can
be
sent
all
over
the
area
for
use
in
making
roads.

16. Porthcawl
Comprehensive
School
March,
2014
16
Final
Solution
The
solution
we
decided
on
as
a
team
was
to
use
an
ultrasonic
transmitter/receiver
unit
with
a
Raspberry
Pi
computer.
This
combination
gives
the
following
benefits:
• The
chosen
sensor
is
very
low
cost.
We
obtained
ours
from
the
internet
for
approximately
£2
• The
Raspberry
Pi
is
a
low
cost
computing
option.
Approximately
£25.
• The
software
code
that
we
have
implemented
is
very
flexible
and
can
be
changed
easily
to:
o Change
the
message
that
is
sent
o Change
the
number
of
recipients
o Change
the
number
of
massages
sent
o Change
the
depth
at
which
the
message
is
triggered
• The
device
can
be
implemented
any
number
of
times
across
the
site
with
very
small
amounts
of
set
up
or
reconfiguration

17. Porthcawl
Comprehensive
School
March,
2014
17
Design
Development
Once
the
technology
and
implementation
had
been
decided
on
we
had
to
build
the
system
to
test
it
on
a
small
scale
in
the
laboratory.
The
equipment
had
been
ordered
from
the
internet
and
the
software
code
was
being
written.
While
this
was
being
done,
the
hardware
had
to
be
constructed
in
order
to
test
the
software
was
working
correctly.
The
software
and
the
hardware
were
then
put
together
to
check
the
system
worked
and
then
put
through
a
period
of
testing
to
ensure
consistent
operation.
Hardware
The
sensor
unit
was
a
basic
unit
with
ultrasonic
transmitter
and
receiver
built
onto
a
circuit
board
with
a
small
amount
of
circuitry
(an
oscillator
and
timing
circuits
to
make
the
ultrasonic
sound
waves
that
are
sent
by
the
transmitter).
This
small
circuit
board
then
required
a
small
amount
of
circuitry
to
make
it
work
with
the
raspberry
pi.
This
circuit
was
a
small
interface
system
to
ensure
that
the
voltage
provided
by
the
raspberry
pi
was
correct
to
drive
the
sensor
and
the
signal
supplied
by
the
sensor
was
correct
for
the
pi
to
be
able
to
understand.
This
circuit
was
first
constructed
on
a
prototyping
board
to
ensure
correct
operation.

18. Porthcawl
Comprehensive
School
March,
2014
18
Once
this
circuit
was
tested
and
could
be
seen
to
work
reliably
it
was
soldered
onto
strip
board
to
make
the
contacts
more
secure
and
resilient.
This
circuit
could
then
be
mounted
in
a
case
to
protect
the
more
sensitive
parts
of
the
circuit
from
damage.
The
sensor
was
interfaced
to
the
Raspberry
Pi
by
using
a
temporary
general
input
output
break
out
board
(GPIO
board).
This
is
a
temporary
measure
and,
because
of
the
nature
of
the
Pi,
these
contacts
could
be
made
directly
to
the
computer
board
by
soldering.
However,
this
would
be
a
final
solution
and
not
for
development.

19. Porthcawl
Comprehensive
School
March,
2014
19
Python
Scripts
The
software
program
script
for
the
Raspberry
Pi
was
written
in
Python
code.
This
is
the
main
programming
language
for
the
raspberry
pi
and
is
becoming
more
popular
among
programmers
in
many
areas
of
computing.
The
following
section
outlines
the
Python
programme
that
was
created
for
this
project.
Unfortunately
the
formatting
has
not
been
retained
–
this
was
lost
when
exporting
the
programme
file
from
the
Pi.
This
formatting
would
have
taken
the
form
of
indenting
different
parts
of
the
program
in
order
to
group
sections
of
the
code
together.
Some
annotation
is
included
in
the
text
in
the
form
of
comments.
These
comments
are
preceded
by
a
hash
icon
(#).
This
is
the
standard
way
that
programmers
annotate
software
to
keep
track
of
their
code.
The
hash
sign
tells
the
program
to
ignore
that
line
as
it
is
not
part
of
the
program.
Annotation
has
been
added
in
the
boxes
on
the
right
of
the
page.
Ultrasonic
distance
measure:
import
time
import
RPi.GPIO
as
GPIO
def
measure():
#
This
function
measures
a
distance
GPIO.output(GPIO_TRIGGER,
True)
time.sleep(0.00001)
GPIO.output(GPIO_TRIGGER,
False)
start
=
time.time()
while
GPIO.input(GPIO_ECHO)==0:
start
=
time.time()
while
GPIO.input(GPIO_ECHO)==1:
stop
=
time.time()
elapsed
=
stop-­‐start
distance
=
(elapsed
*
34300)/2
return
distance
def
measure_average():
distance1=measure()
time.sleep(0.1)
Functions
such
as
the
General
Purpose
Input
Output
library
must
be
allocated
to
this
program.
This
section
of
the
code
is
how
the
Pi
is
able
to
measure
distance.
The
Ultrasonic
unit
transmits
a
pulse
of
high
frequency
sound
waves
(GPIO
Trigger
True)
and
then
starts
a
timer.
The
timer
is
stopped
when
the
echo
is
detected
at
the
sensor.
This
equation
then
takes
the
recorded
time
and
mulitplies
it
by
the
speed
of
sound
in
air.
This
is
approximately
34300
cm/s.
This
number
is
then
divided
by
two
in
order
to
find
the
distance
from
the
sensor
to
the
surface
of
the
liquid
–
not
the
total
path
length
the
sound
wave
has
travelled.

20. Porthcawl
Comprehensive
School
March,
2014
20
distance2=measure()
time.sleep(0.1)
distance3=measure()
distance
=
distance1
+
distance2
+
distance3
distance
=
distance
/
3
return
distance
#
Main
Script
#
Use
BCM
GPIO
references
#
instead
of
physical
pin
numbers
GPIO.setmode(GPIO.BCM)
#
Define
GPIO
Pins
to
use
on
Pi
GPIO_TRIGGER
=
23
GPIO_ECHO
=
24
print
"Ultrasonic
Measurement"
#
Set
pins
as
output
and
input
GPIO.setup(GPIO_TRIGGER,GPIO.OUT)
#
Trigger
GPIO.setup(GPIO_ECHO,GPIO.IN)
#
Echo
#
Set
trigger
to
False
(Low)
GPIO.output(GPIO_TRIGGER,
False)
try:
while
True:
distance
=
measure_average()
print
"Distance
:
%.1f"
%
distance
time.sleep(1)
#trigger
SMS1
when
distance
is
greater
than
40
cm
if
distance
>
40:
This
section
of
the
code
takes
three
measurements
of
the
distance
and
then
takes
anmean
average
of
the
results.
This
helps
in
making
the
measurement
more
accurate.
This
section
of
the
code
begins
to
define
the
levels
at
which
the
alarms
will
be
raised.
This
will
be
short
distances
set
for
our
model
but
this
can
be
adjusted
very
easily
for
any
size
of
tank
or
silo.

21. Porthcawl
Comprehensive
School
March,
2014
21
sms
except
KeyboardInterrupt:
#
User
pressed
CTRL-­‐C
#
Reset
GPIO
settings
GPIO.cleanup()
def
SMS(
Code
to
send
SMS
#
Import
required
libraries
import
urllib
#
URL
functions
import
urllib2
#
URL
functions
#
Define
your
message
message
=
'Refill
bitumen
tank
number
1
-­‐
Cornelly
Quarry'
#
Set
your
username
and
sender
name.
username
=
'lawson.richard@hotmail.com'
sender
=
'Porthcawl
EESW
Team
#
Your
unique
hash
is
available
from
the
docs
page
#
https://control.txtlocal.co.uk/docs/
hash
=
'86cee22e249d8e18f09bd0b7bed6821ea6c72cf1'
#
Set
the
phone
number
numbers
=
('447855272195')
#
Set
flag
to
1
to
simulate
sending
#
To
send
real
message
set
this
flag
to
0
test_flag
=
1
values
=
{'test'
:
test_flag,
'uname'
:
username,
'hash'
:
hash,
'message'
:
message,
'from'
:
sender,
CTRL-­‐C
is
the
standard
code
to
interrupt
a
program
that
is
running.
In
this
case
it
is
also
being
used
to
reset
the
inputs
and
outputs
of
the
Pi.
This
section
of
the
code
will
send
the
message
to
amobile
phone
via
the
internet
service
“text
local”.
This
service
was
selected
as
it
enables
remote
and
automatic
log
in
using
the
provided
“Hash
Code”
The
service
requires
a
administrator
to
maintain
control
of
the
system
so
our
teacher,
Mr
Lawson
has
signed
in
with
his
details,
This
is
the
Hash
code
provided
by
the
website
This
script
can
send
text
messages
to
individual
phones
or
a
group
of
phones
numbers
if
required.
This
is
where
the
phone
number(s)
to
be
used
is
entered.
As
text
messages
cost
money
to
send
(10p)
then
we
have
included
the
ability
to
simulate
sending
a
text
for
testing
the
system
and
to
keep
costs
to
a
minimum
during
development.

22. Porthcawl
Comprehensive
School
March,
2014
22
'selectednums'
:
numbers
}
url
=
'http://www.txtlocal.com/sendsmspost.php'
postdata
=
urllib.urlencode(values)
req
=
urllib2.Request(url,
postdata)
print
'Attempt
to
send
SMS
...
'
try:
response
=
urllib2.urlopen(req)
response_url
=
response.geturl()
if
response_url==url:
print
'SMS
sent!'
except
urllib2.URLError,
e:
print
'Send
failed!'
print
e.reason
#
Import
required
libraries
import
urllib
#
URL
functions
import
urllib2
#
URL
functions
#
Define
your
message
message
=
'URGENT!
–
Level
Low:
Refill
bitumen
tank
number
1
-­‐
Cornelly
Quarry'
#
Set
your
username
and
sender
name.
username
=
'lawson.richard@hotmail.com'
sender
=
'Porthcawl
EESW
Team’
#
Your
unique
hash
is
available
from
the
docs
page
#
https://control.txtlocal.co.uk/docs/
hash
=
'86cee22e249d8e18f09bd0b7bed6821ea6c72cf1'
#
Set
the
phone
number
you
wish
to
send
The
program
will
print
progress
messages
on
the
screen
and
confirmation
that
the
text
has
been
sent.
This
is
mainly
for
the
development
stage
as
during
main
use
the
screen
will
not
be
required.
It
will
tell
us
if
the
send
has
failed
or
succeeded.
This
works
even
in
simulated
test
mode.
This
section
of
the
program
is
a
copy
and
repeat
of
the
previous
section.
This
was
the
easiest
way
to
enable
us
to
send
different
messages
at
different
times.
This
is
difficult
to
see
here
as
the
indent
formatting
did
not
keep.

23. Porthcawl
Comprehensive
School
March,
2014
23
#
message
to.
numbers
=
('447855272195')
#
Set
flag
to
1
to
simulate
sending
#
To
send
real
message
set
this
flag
to
0
test_flag
=
1
values
=
{'test'
:
test_flag,
'uname'
:
username,
'hash'
:
hash,
'message'
:
message,
'from'
:
sender,
'selectednums'
:
numbers
}
url
=
'http://www.txtlocal.com/sendsmspost.php'
postdata
=
urllib.urlencode(values)
req
=
urllib2.Request(url,
postdata)
print
'Attempt
to
send
SMS
...
'
try:
response
=
urllib2.urlopen(req)
response_url
=
response.geturl()
if
response_url==url:
print
'SMS
sent!'
except
urllib2.URLError,
e:
print
'Send
failed!'
print
e.reason
Though
a
repeated
part
of
the
program,
this
is
a
key
part
of
the
operation.
This
function
can
be
replicated
for
different
distances
within
the
tank
allowing
early
warning
messages
to
be
sent,
emergency
low
level
messages
or
test
messages.
This
function
could
be
expanded
by
the
company
at
any
point
and
very
easily
to
enable
the
system
to
become
more
flexible
depending
on
changing
needs.

24. Porthcawl
Comprehensive
School
March,
2014
24
Prototype
Testing
The
prototype
system
was
tested
on
a
small
scale.
The
site
where
this
system
would
normally
be
used
is
a
very
dangerous
environment.
The
sensor
would
have
to
be
set
up
inside
the
bitumen
tank
and
the
bitumen
is
held
at
a
very
high
temperature
to
make
sure
it
remains
liquid.
This
raises
the
possibility
that
the
sensor
would
not
work
properly
in
his
environment
but
this
is
impossible
for
us
to
test
within
the
scope
of
this
project.
So,
to
test
the
concept
of
the
system
we
built
a
scale
model
of
the
bitumen
tank
on
site,
scaled
the
trigger
thresholds
in
the
software
and
constructed
a
mount
to
hold
the
sensor
unit
at
the
top
of
the
tank.
After
much
discussion
we
finally
selected
our
equipment
to
use
for
our
testing
and
display
model.
The
first
step
in
building
our
model
was
ordering
the
equipment.
Some
of
the
equipment
used
was
sourced
or
built
in
school.
For
example
the
casing
for
our
raspberry
pi
was
found
and
then
modified
in
order
to
hold
the
pi
and
keep
it
safe.
The
casing
for
the
ultrasonic
sensor
was
also
modified
to
hold
the
sensor.
We
then
used
a
high
speed
drill
to
cut
a
hole
for
the
tap.
We
did
this
by
drilling
lots
of
holes
close
together
and
then
pushing
the
plastic
out.
We
chose
to
do
it
this
way
as
it
had
the
lowest
risk
of
the
plastic
splitting
as
we
were
cutting.
We
then
put
the
tap
in
place
making
sure
to
use
the
gaskets
provided
to
stop
the
risk
of
leaking.
The
piping
was
then
attached.
We
also
added
stickers
to
the
tanks
to
make
them
look
more
realistic.
We
have
also
used
a
bubble
machine
in
order
to
make
the
liquid
look
like
its
hot.
To
start
we
needed
a
container
to
hold
x
amount
of
(material)
so
before
building
an
actual
physical
model
a
design
was
first
created
to
replicate
the
specification
given.
First
purely
the
cylinder
and
base
were
created
with
the
measurements
of
(insert
dimensions)
and
volume
of
(insert
volume)
as
shown
in
fig
1.
Secondly
the
lid
was
designed
the
original
design
was
to
cover
the
entire
top
surface
as
shown
in
fig
2.
However
later
design
proved
that
due
to
the
use
of
sonar
as
the
method
of
measurement
it
was
better
to
have
a
half
covered
surface
to
avoid
any
echo
or
at
least

25. Porthcawl
Comprehensive
School
March,
2014
25
avoid
most
to
give
more
reliable
results
when
measuring
the
volume
of
liquid
in
the
container.
The
final
result
with
the
sonar
device
is
as
shown
in
fig
3.
Using
this
rig,
the
tank
was
filled
and
drained
many
times.
First
the
rig
was
tested
with
the
test
flag
set
in
the
software.
This
meant
that
the
levels
could
be
monitored
and
the
computer
would
signal
that
a
text
message
would
be
sent.
Once
this
was
working
successfully,
the
test
flag
could
be
removed
and
so
the
system
would
send
real
text
messages
over
the
internet.
This
was
first
done
for
members
of
the
team
and
our
teacher.
Then
we
attempted
to
send
a
series
of
texts
to
our
Engineer,
Mr
Jones
by
simply
changing
the
water
level
in
the
test
tank.
This
was
a
great
success
and
showed
that
the
system
was
reliable
in
sending
the
messages.
The
only
problem
we
encountered
at
this
stage
was
that
occasionally,
the
system
would
send
two
or
three
text
messages
in
a
row
instead
of
a
single
text.
The
reason
for
this
is
unknown
but
the
problem
of
sending
too
many
text
messages
is
better
than
not
sending
any.

26. Porthcawl
Comprehensive
School
March,
2014
26
Results,
Discussion
and
Evaluation
The
benefits
of
this
system
being
implemented
in
the
Tarmac
company
are
broad
and
far
reaching.
This
section
will
aim
to
summarise
the
main
points
that
will
benefit
the
company.
Environmental
Benefits
As
the
bitumen
used
is
ordered
and
so
delivered
from
Birkenhead,
this
obviously
has
an
impact
on
the
environment
as
a
whole.
The
tanker
lorries
that
deliver
the
bitumen
to
site
have
to
travel
231
miles
(371
km)
on
their
journey
from
Birkenhead
to
Cornelly
Quarry.
This
is
an
unavoidable
journey
but
still
causes
a
significant
CO2
contribution
to
atmospheric
pollution.
The
following
table
shows
how,
on
average
vehicles
contribute
to
global
warming
with
CO2
emissions:
Bitumen
is
delivered
in
25
tonne
loads
by
large
tanker
trucks.
Depending
on
the
size
of
the
truck
and
engine
being
used,
the
CO2
produced
is
generally
between
3.0
and
3.9
kg/tonne/km.
If
we
take
an
average
pollution
rate
of
3.4
kg/tonne/km
then
we
can
calculate
the
pollution
per
journey
as
follows:
This
will
be
consistent
for
the
371
km
journey
so
will
generate:
Total
kg
per
journey
=
371
km
x
3.4
kg/km
=
1,261
kg
of
CO2
per
journey
Although
the
tanker
will
have
unloaded
the
25
tonnes
of
liquid
at
Cornelly,
the
return
journey
must
also
be
factored
in
as
this
is
an
inevitable
part
of
the
process.

27. Porthcawl
Comprehensive
School
March,
2014
27
Total
kg
per
delivery
=
1,261
x
2
=
2,523
kg
It
is
estimated
by
the
company
that
unnecessary
part
loads
are
ordered
on
average
10
times
each
year.
This
is
the
type
of
journey
that
is
caused
by
poor
level
control
and
so
the
type
of
pollution
our
system
will
aim
to
eliminate.
So
the
total
unnecessary
CO2
generated
per
year:
Total
CO2
per
year
=
2,523
kg
x
10
=
25,230
kg
CO2
per
year
This
is
a
very
large
amount
of
pollution
that
could
be
reduced
very
simply
by
implementing
our
device.
Development
Costs
The
costs
of
developing
this
system
were
actually
very
small.
The
Raspberry
Pi
computer
generally
retails
for
about
£25.
The
Ultrasonic
transceiver
costs
approximately
£2.
The
cases
and
hardware
were
surplus
to
requirements
and
so
were
free
to
the
project
though
normally
they
would
cost
less
than
£10
in
total.
The
actual
cost
to
create
this
system
in
a
form
that
could
be
used
therefore
is
about
£40
in
total.
However,
there
were
more
costs
involved
in
development
than
merely
constructing
the
system.
The
test
rig
and
tanks
were
the
single
biggest
expense.
These
alone
cost
£136.
This
seems
like
a
very
large
expenditure
when
compared
to
the
rest
of
the
system
but
it
was
considered
important
to
have
a
test
system
that
was
similar
in
shape
and
scale
dimensions
to
the
actual
storage
tanks
on
site.
The
text
messaging
service
used,
“Text
Local”
is
a
py
per
use
service.
It
is
free
to
register
and
gain
an
account.
This
account
even
comes
with
£10
of
free
text
messages.
As
testing
continued,
we
began
to
run
out
of
text
messages.
We
contacted
the
text
service
providers
and
explained
the
idea
behind
the
EESW
scheme
and
they
agreed
to
provide
us
with
a
further
50
text
message
credits
with
the
offer
of
more
if
this
did
not
prove
sufficient.

28. Porthcawl
Comprehensive
School
March,
2014
28
Cost
Benefits
The
cost
benefits
to
this
system
are
very
significant.
These
benefits
can
be
outlined
as
follows:
A
full
tank
of
bitumen
delivered
from
Birkenhead
is
25
tonnes
at
£550
per
tonne.
This
means
that
each
tanker
load
costs
£13,750.
If
a
part
load
is
required,
these
loads
are
15
tonnes.
However,
the
cost
of
this
delivery
is
still
£13,750.
Effectively
the
company
is
charged
a
premium
if
the
tanker
is
not
full.
It
is
therefore
in
the
companies
best
interest
to
ensure
that
only
full
loads
are
being
ordered.
Each
time
this
happens,
although
the
tanker
is
delivering
10
tonnes
less
than
normal,
the
company
is
still
charged
for
these
10
missing
tonnes
at
£550/tonne.
So
the
company
pays
£5,500
for
bitumen
it
does
not
receive.
As
mentioned
above,
this
is
estimated
to
happen
currently
approximately
10
times
each
year.
This
equates
to
£5,500
per
tank.
Cornelly
has
4
tanks
so
this
could
be
as
much
as
£22,000
per
site.
Cornelly
also
has
smaller
tanks
than
other
sites
in
the
company.
Some
quarry
sites
have
100
tonne
tanks
instead
of
50
tonnes
tanks.
This
will
therefore
increase
the
amount
of
wasted
journeys
and
money.
The
cost
benefits
are
also
more
widespread
than
straight
forward
purchasing.
The
fact
that
the
system
will
be
automatic
enables
an
engineer
to
be
redeployed
elsewhere
on
site
instead
of
having
to
monitor
tank
levels.
This
will
help
the
site
to
run
more
efficiently
and
more
productively.
The
increased
productivity
and
efficiency
will
also
enable
the
company
to
maintain
better
relationships
with
their
clients
and
will
be
able
to
fulfil
more
orders
more
quickly
and
will
therefore
help
to
grow
their
business
and
reputation.
Health
and
Safety
This
system
also
delivers
safety
benefits.
Each
time
the
lorry
driver
discharges
a
tanker
load
of
bitumen,
he
is
exposed
to
liquids
held
at
temperatures
in
excess
of
120
o
C.
This
means
he
must
wear
special
safety
clothing
and
runs
the
risk
of
accidental
spills.
He
is
also
exposed
to
the
fumes
and
gases
given
off
by
such
a
dangerous
and
volatile
substance.

29. Porthcawl
Comprehensive
School
March,
2014
29
Wider
Scope
of
Project
By
the
time
this
project
had
been
finished
and
tested
to
prove
it
worked,
we
began
to
realise
the
full
potential
of
this
project.
While
this
has
been
demonstrated
to
be
a
huge
benefit
to
Lafarge
Tarmac
in
the
remote
monitoring
of
Bitumen
level,
it
could
be
used
anywhere
a
level
in
a
container
needs
to
be
monitored.
For
example,
any
liquid,
not
just
bitumen,
could
be
monitored.
This
could
include
any
type
of
fluid
required
in
manufacturing,
chemicals
in
industrial
plants,
ingredients
in
food
manufacturing,
petrol/diesel
levels
in
mass
storage
tanks
or
petrol
stations
or
water
in
swimming
pools.
The
list
of
liquids
that
could
be
measured
is
literally
endless.
As
this
system
is
ultrasonic,
it
does
not
necessarily
have
to
be
a
liquid
to
be
measured.
This
would
work
equally
well
in
a
farms
grain
silo,
a
bread
factory’s
flour
silo
or
building
sites
for
monitoring
sand
or
cement
powder
in
the
construction
industry.
This
could
also
be
a
very
important
way
of
helping
people
in
developing
countries.
For
example,
this
device
could
be
installed
in
a
drinking
water
well
and
could
alert
people
of
falling
water
levels
so
that
help
can
be
sought
or
contingency
plans
could
be
put
in
place.

30. Porthcawl
Comprehensive
School
March,
2014
30
Conclusion
The
unit
designed
fulfilled
the
design
brief
in
operation.
It
has
proved
able
to
detect
the
level
of
liquid
within
a
large
tank
with
a
high
degree
of
accuracy.
It
has
also
proved
to
be
reliable
and
issued
at
least
one
text
message
each
time
the
liquid
threshold
levels
were
reached.
Occasionally
more
than
one
SMS
was
transmitted
but
as
previously
mentioned
this
was
not
seen
as
an
issue
as
the
message
would
still
have
got
through
to
the
engineer.
The
greatest
area
of
success
which
we
did
not
originally
intend
to
be
so
great
was
the
proven
cost
saving
that
this
small
unit
could,
and
will
achieve.
These
are
complimented
by
huge
savings
in
environmental
factors
such
as
CO2
output
and
the
benefit
to
the
perception
of
the
company
by
clients
and
competitors.
As
previously
mentioned
this
project
has
the
potential
to
help
wider
industry
and
is
not
just
limited
to
bitumen
monitoring
in
the
manufacture
of
asphalt.
As
a
team,
we
have
designed,
developed
and
delivered
a
robust
solution
to
a
very
challenging
problem.
This
design
has
been
built
and
tested
and
has
shown
that
it
can
work
reliably.
The
main
limitation
of
the
system
developed
so
far
is
that
it
cannot
at
present
be
installed
on
site.
For
this
to
take
place
it
would
have
to
be
formally
tested
for
Electromagnetic
Compatibility,
safety
testing
and
would
need
to
be
ruggedized
to
make
sure
it
will
withstand
the
harsh
environments
on
site.
However,
this
would
be
a
relatively
small
investment
and
as
such,
this
device
has
shown
that
it
can
provide
very
substantial
cost
saving,
enormous
environmental
benefits
and
can
be
used
in
many
different
situations.

31. Porthcawl
Comprehensive
School
March,
2014
31
Appendix
The
following
appendix
shows
examples
of
the
systems
that
were
used
to
ensure
the
work
was
completed
in
an
orderly
and
timely
manner.

32. Porthcawl
Comprehensive
School
March,
2014
32
Action
Log
This
spreadsheet
shows
an
early
example
of
the
progress
log
that
was
used
to
keep
track
of
tasks
within
the
team
and
to
keep
our
Engineer
informed.