PlymBridge Peregrine Watch Power

TX = Transmitter

RX = Receiver

Power Communications for the web cam at Cann Quarry
This article sets out to explain how The Plymouth College of Further Education in partnership with The National Trust overcame the problems associated with the installation of a web cam, set-up to transmit live video pictures via the Internet, of a pair of Peregrine Falcons nesting in an isolated quarry.

This project would have foundered at an early stage if it had not been for the financial help from English Nature and the advice and assistance freely given by a number of local companies.

The Past
Two hundred and fifty years ago, well before the age of combustion engines and electric motors, a time when the invention of the steam engine was still over the horizon, the quarrymen of Cann faced a problem familiar to any engineering enterprise of that age; a source of power to cut and dress the slate they removed from the quarry face.

They did not have to look very far for a solution; almost at the foot of the quarry flowed the river Plym, whose source high up on Dartmoor ensured that this fast flowing river could be relied upon to supply abundant energy throughout the year.The proximity of the river would have clearly been a factor in the choice of the quarry site.

To harness this energy a weir was built just upstream from the quarry to divert a flow of water through a short underground canal into the heart of the quarry workings.This allowed the varying flow of water in the river to be kept constant within the canal by a system of sluice gates at the weir inlet. The canal could now be used to turn water wheels and convert the flow of water to rotational movement to power the quarry machinery.

The Present
Today, little has changed at the quarry; time has literally stood still since the last piece of slate was transported away in 1866. Cann Quarry is still isolated from all the modern conveniences we now take for granted, there are no roads, no electricity or telephones, there used to be railway passing through the valley but even that has now gone.

The quarrymen would have sympathised with the problems facing The National Trust and Plymouth College of Further Education, when the decision was made to install a camera to monitor the progress of a pair of Peregrine Falcons now nesting on the deserted quarry face.

The aim of this ambitious project was to set up a web cam focused on the Peregrines eyrie.

One of the attractions of the project was the unique location and the possibility that this could be the first web cam showing wild Peregrines nesting at a natural site. If the project was to succeed, the same problems faced by the quarrymen over two centuries before would now need to be addressed.

The two main areas of concern was first the generation of sufficient electricity to power all the essential electronic equipment and secondly the transmission of the live pictures from the camera to the outside world.

The Solution
The power options to consider were simply water, wind and sunlight (solar).

The option of transporting batteries or using a petrol generator were rejected on environmental and practical grounds at an early stage of the project.

Water power to drive a turbine would have been the ideal solution, the only problem being, the equipment we needed to supply with electricity was at the top of the quarry and the River Plym at the bottom and outside the quarry. The security of and the length of a cable running from a water turbine made this option impractical (transmission of low voltages over long distances result in significant losses within the cable).

This just left wind and solar energy. It was finally decided that both forms of energy should be taken advantage of. The fact that some of the electronic equipment would not be in use during the hours of darkness was also taken into consideration.

Wind Turbine.
The final choice was a Rutland 910-3 Furlmatic, this unit is capable of supplying up to 6 Amp at 24 Volts in a gale, but in practice currents of 1-2 Amps would be achieved in wind speeds of 5-10 Metres per second. This unit also has the additional advantage of automatically turning itself away from the wind when wind speeds threaten to damage the turbine.

Nature has reclaimed Cann Quarry and mature deciduous trees densely populate the quarry edge; choosing a site to locate the wind turbine now presented itself as the next challenge. Ground level was out of the question as air flow was erratic and turbulent. Placing the turbine in a tree was discounted for the same reasons and there was also the risk of the Peregrines or other birds flying into the turbine blades.

Directly behind the quarry is an extensive plantation of Larch trees with some cleared areas all of which belongs to the Forestry Commission. The National Trust sought and was kindly given permission by the Forestry Commission to erect a mast for the turbine within one of the clearings.

Further investigation of the site on a windy day cast doubts on the clearings suitability, even though the clearing was quite large, the surrounding trees proved to be a very effective wind break.

The only obvious solution to obtain "clear air" would be to erect the turbine mast above the height of the surrounding trees. With the trees standing at approximately 22 metres this was not going to be a simple task.

The Forestry Commission on the suggestion of Gus Ferguson the NT warden solved part of the problem by allowing the removal of the top third of a Larch tree leaving us with a pole to attach the turbine mast.

Obtaining a 22 metre mast strong enough to support 17 kg of wind turbine could have placed the project in jeopardy on cost grounds alone if it had not been for the help of a local manufacturer of metal tubing.

The company in question was Fine Tubes Ltd, who after a site visit to assess the problem and see for themselves what we were trying to achieve to protect the Peregrines, offered their support and their expertise, to help us erect the mast. At the time of writing Fine Tubes Ltd are in the process of producing a suitable mast.

Solar Panels
To supplement the power from the wind turbine two 30 Watt solar panels have been purchased. These will be mounted on Larch trees at the south facing edge of the clearing mentioned above.

It is accepted that the power output from the solar panels on their own will be insufficient to power the system from solar energy alone, but they should give a useful boost during periods of still air and sunshine, especially during the couple of hours either side of midday.

Batteries
The output from both the wind turbine and the solar panels will be used to maintain the charge, via a control unit, of four 12 Volt 110 Amp hour leisure batteries. The batteries are wired in series-parallel to give an output of 24 Volts.
There are contingency plans to charge the batteries from a petrol generator after long periods of still and overcast weather.

Communications
Normally web cams are connected to a computer and then to the Internet via the local telecommunications network. The situation at Cann Quarry precludes this, as already mentioned there are no telephone lines in the area.
The original plan was to use a laptop computer and a radio link, set-up at the quarry, to stream video from the camera to one of the local factories on the horizon of the opposite side of the valley, approximately 1 km from the quarry.
Once again a local company, in this case The Essa Security Group of Saltash came up with a more novel solution.
Essa supplied us free of charge with a second hand microwave link capable of transmitting live video transmissions of high quality. This now meant we no longer needed a computer at the Cann Quarry site draining power from our batteries.

By their very nature microwave transmitters are line of sight devices, so we still needed a factory on the opposite side of the valley to locate the microwave receiver and house the computer to stream the video. The nearest factory could be seen just above the trees on the skyline, that factory belonged to The Wrigley Company Ltd (UK). The company was approached and readily agreed to the siting of the microwave receiver on the roof of their factory, they also allowed the installation of a computer to stream the video. The company have plans to install a television in their canteen to show live pictures from the Peregrine eyrie.

Camera
In the initial planing stage of the project it was assumed that a relatively basic web camera could be placed near to the Peregrine nest site. This assumption was partly based on viewing other web sites, in the main American, which had been set up to observe man made nest sites on artificial structures.

The Cann Quarry site is a natural site where the Peregrines have chosen to nest without any human encouragement. Traditionally Peregrines usually choose to nest on a cliff where the eggs are laid on a bare ledge high up on the rock face. At Cann the Peregrines have taken this one step further and use the disused nests of Ravens who also take advantage of the quarry to rear their young.

The Ravens have bred at Cann for many years and in consequence there are a number of old nests spread across the face of the quarry. Compared to other Peregrine web sites this placed the planning team at a disadvantage, as there was no way of predicting in advance exactly where the Peregrines would nest the following season.

The National Trust and the PCFE approached ADT Fire & Security another local company based on the perimeter of Plymbridge woods with a request for help and advice on the purchase of a suitable camera. Initially our request was for a second hand camera and housing which we would then set-up close to the most likely eyrie to be used by the Peregrines. Brackets designed to accept the camera would be fixed to the rock face, enabling us if necessary, to change the camera location at short notice.

ADT Fire & Security spent some considerable time demonstrating the different types of camera systems available, both at their premises and at the quarry itself.The type of camera recommended by ADT was a fully functional pan, tilt and zoom camera with telemetry for remote control.This opened up the possibility of remotely tracking the young Peregrines with the camera as they moved away from the immediate vicinity of the eyrie later on in the season, as a consequence this would extend the period of time that the Peregrines would be in view on the web cam.

Even with ADT's offer to supply at cost, the decision to purchase was not easy, this camera would be the single most expensive item of the projects budget. In the end it was decided that the advantages of the camera outweighed other considerations.The remote telemetry to control the camera will be set up in a caravan on top of the quarry, from here a National Trust warden will take control off which aspects of the Peregrines are viewed over the Internet.

The Future
By the spring of 2003 all the basic power and communication facilities will be up and running, allowing the progress of the Peregrines to be viewed live on the web site.

Plymouth College of Further Education in partnership with students at Devonport High School For Boys will continue to develop the technical facilities at the quarry.

Examples of current projects under development include a sensor to automatically turn off the camera and transmitter at dusk, and back on at dawn. Investigation will also be undertaken for a wireless video link from the camera to a video screen housed in the information centre located on the Cann railway viaduct.



		The animation below shows the engineering used in bringing live images to the World Wide Web, scroll down to read more.
		TX = Transmitter RX = Receiver Power Communications for the web cam at Cann Quarry This article sets out to explain how The Plymouth College of Further Education in partnership with The National Trust overcame the problems associated with the installation of a web cam, set-up to transmit live video pictures via the Internet, of a pair of Peregrine Falcons nesting in an isolated quarry. This project would have foundered at an early stage if it had not been for the financial help from English Nature and the advice and assistance freely given by a number of local companies. The Past Two hundred and fifty years ago, well before the age of combustion engines and electric motors, a time when the invention of the steam engine was still over the horizon, the quarrymen of Cann faced a problem familiar to any engineering enterprise of that age; a source of power to cut and dress the slate they removed from the quarry face. They did not have to look very far for a solution; almost at the foot of the quarry flowed the river Plym, whose source high up on Dartmoor ensured that this fast flowing river could be relied upon to supply abundant energy throughout the year.The proximity of the river would have clearly been a factor in the choice of the quarry site. To harness this energy a weir was built just upstream from the quarry to divert a flow of water through a short underground canal into the heart of the quarry workings.This allowed the varying flow of water in the river to be kept constant within the canal by a system of sluice gates at the weir inlet. The canal could now be used to turn water wheels and convert the flow of water to rotational movement to power the quarry machinery. The Present Today, little has changed at the quarry; time has literally stood still since the last piece of slate was transported away in 1866. Cann Quarry is still isolated from all the modern conveniences we now take for granted, there are no roads, no electricity or telephones, there used to be railway passing through the valley but even that has now gone. The quarrymen would have sympathised with the problems facing The National Trust and Plymouth College of Further Education, when the decision was made to install a camera to monitor the progress of a pair of Peregrine Falcons now nesting on the deserted quarry face. The aim of this ambitious project was to set up a web cam focused on the Peregrines eyrie. One of the attractions of the project was the unique location and the possibility that this could be the first web cam showing wild Peregrines nesting at a natural site. If the project was to succeed, the same problems faced by the quarrymen over two centuries before would now need to be addressed. The two main areas of concern was first the generation of sufficient electricity to power all the essential electronic equipment and secondly the transmission of the live pictures from the camera to the outside world. The Solution The power options to consider were simply water, wind and sunlight (solar). The option of transporting batteries or using a petrol generator were rejected on environmental and practical grounds at an early stage of the project. Water power to drive a turbine would have been the ideal solution, the only problem being, the equipment we needed to supply with electricity was at the top of the quarry and the River Plym at the bottom and outside the quarry. The security of and the length of a cable running from a water turbine made this option impractical (transmission of low voltages over long distances result in significant losses within the cable). This just left wind and solar energy. It was finally decided that both forms of energy should be taken advantage of. The fact that some of the electronic equipment would not be in use during the hours of darkness was also taken into consideration. Wind Turbine. The final choice was a Rutland 910-3 Furlmatic, this unit is capable of supplying up to 6 Amp at 24 Volts in a gale, but in practice currents of 1-2 Amps would be achieved in wind speeds of 5-10 Metres per second. This unit also has the additional advantage of automatically turning itself away from the wind when wind speeds threaten to damage the turbine. Nature has reclaimed Cann Quarry and mature deciduous trees densely populate the quarry edge; choosing a site to locate the wind turbine now presented itself as the next challenge. Ground level was out of the question as air flow was erratic and turbulent. Placing the turbine in a tree was discounted for the same reasons and there was also the risk of the Peregrines or other birds flying into the turbine blades. Directly behind the quarry is an extensive plantation of Larch trees with some cleared areas all of which belongs to the Forestry Commission. The National Trust sought and was kindly given permission by the Forestry Commission to erect a mast for the turbine within one of the clearings. Further investigation of the site on a windy day cast doubts on the clearings suitability, even though the clearing was quite large, the surrounding trees proved to be a very effective wind break. The only obvious solution to obtain "clear air" would be to erect the turbine mast above the height of the surrounding trees. With the trees standing at approximately 22 metres this was not going to be a simple task. The Forestry Commission on the suggestion of Gus Ferguson the NT warden solved part of the problem by allowing the removal of the top third of a Larch tree leaving us with a pole to attach the turbine mast. Obtaining a 22 metre mast strong enough to support 17 kg of wind turbine could have placed the project in jeopardy on cost grounds alone if it had not been for the help of a local manufacturer of metal tubing. The company in question was Fine Tubes Ltd, who after a site visit to assess the problem and see for themselves what we were trying to achieve to protect the Peregrines, offered their support and their expertise, to help us erect the mast. At the time of writing Fine Tubes Ltd are in the process of producing a suitable mast. Solar Panels To supplement the power from the wind turbine two 30 Watt solar panels have been purchased. These will be mounted on Larch trees at the south facing edge of the clearing mentioned above. It is accepted that the power output from the solar panels on their own will be insufficient to power the system from solar energy alone, but they should give a useful boost during periods of still air and sunshine, especially during the couple of hours either side of midday. Batteries The output from both the wind turbine and the solar panels will be used to maintain the charge, via a control unit, of four 12 Volt 110 Amp hour leisure batteries. The batteries are wired in series-parallel to give an output of 24 Volts. There are contingency plans to charge the batteries from a petrol generator after long periods of still and overcast weather. Communications Normally web cams are connected to a computer and then to the Internet via the local telecommunications network. The situation at Cann Quarry precludes this, as already mentioned there are no telephone lines in the area. The original plan was to use a laptop computer and a radio link, set-up at the quarry, to stream video from the camera to one of the local factories on the horizon of the opposite side of the valley, approximately 1 km from the quarry. Once again a local company, in this case The Essa Security Group of Saltash came up with a more novel solution. Essa supplied us free of charge with a second hand microwave link capable of transmitting live video transmissions of high quality. This now meant we no longer needed a computer at the Cann Quarry site draining power from our batteries. By their very nature microwave transmitters are line of sight devices, so we still needed a factory on the opposite side of the valley to locate the microwave receiver and house the computer to stream the video. The nearest factory could be seen just above the trees on the skyline, that factory belonged to The Wrigley Company Ltd (UK). The company was approached and readily agreed to the siting of the microwave receiver on the roof of their factory, they also allowed the installation of a computer to stream the video. The company have plans to install a television in their canteen to show live pictures from the Peregrine eyrie. Camera In the initial planing stage of the project it was assumed that a relatively basic web camera could be placed near to the Peregrine nest site. This assumption was partly based on viewing other web sites, in the main American, which had been set up to observe man made nest sites on artificial structures. The Cann Quarry site is a natural site where the Peregrines have chosen to nest without any human encouragement. Traditionally Peregrines usually choose to nest on a cliff where the eggs are laid on a bare ledge high up on the rock face. At Cann the Peregrines have taken this one step further and use the disused nests of Ravens who also take advantage of the quarry to rear their young. The Ravens have bred at Cann for many years and in consequence there are a number of old nests spread across the face of the quarry. Compared to other Peregrine web sites this placed the planning team at a disadvantage, as there was no way of predicting in advance exactly where the Peregrines would nest the following season. The National Trust and the PCFE approached ADT Fire & Security another local company based on the perimeter of Plymbridge woods with a request for help and advice on the purchase of a suitable camera. Initially our request was for a second hand camera and housing which we would then set-up close to the most likely eyrie to be used by the Peregrines. Brackets designed to accept the camera would be fixed to the rock face, enabling us if necessary, to change the camera location at short notice. ADT Fire & Security spent some considerable time demonstrating the different types of camera systems available, both at their premises and at the quarry itself.The type of camera recommended by ADT was a fully functional pan, tilt and zoom camera with telemetry for remote control.This opened up the possibility of remotely tracking the young Peregrines with the camera as they moved away from the immediate vicinity of the eyrie later on in the season, as a consequence this would extend the period of time that the Peregrines would be in view on the web cam. Even with ADT's offer to supply at cost, the decision to purchase was not easy, this camera would be the single most expensive item of the projects budget. In the end it was decided that the advantages of the camera outweighed other considerations.The remote telemetry to control the camera will be set up in a caravan on top of the quarry, from here a National Trust warden will take control off which aspects of the Peregrines are viewed over the Internet. The Future By the spring of 2003 all the basic power and communication facilities will be up and running, allowing the progress of the Peregrines to be viewed live on the web site. Plymouth College of Further Education in partnership with students at Devonport High School For Boys will continue to develop the technical facilities at the quarry. Examples of current projects under development include a sensor to automatically turn off the camera and transmitter at dusk, and back on at dawn. Investigation will also be undertaken for a wireless video link from the camera to a video screen housed in the information centre located on the Cann railway viaduct.