Float Mesh

Float Mesh is a distributed infrastructure in the air, alleviating satellite problems like increasing congestion in near earth space and exclusive access to few.

High-Altitude Platform Systems (HAPS) at 20km or above from the ground are better than satellites in a lot of aspects but their costs are still too high thus ownership will remain centralised.

Float Mesh at 3km or below (normally only 200 metres from the ground) is substantially cheaper and can be deployed easily by farmers, miners, remote towns etc. themselves.

Look around you, find the highest point, put one there ... it is that simple.

1. Introduction

Float Mesh is a network of low cost low altitude tethered balloons that does NOT need to come down. It a low cost and high function terrestrial alternative to having satellites in space.

  1. Radio relay (e.g. WiFi) to provide Internet access (voice and data) in remote areas without good communications or in existing cell tower black spots.
  2. Radio beacon (e.g. WiFi) to allow satellite independent geo-positioning.
  3. Refuel station for UAVs (e.g. with battery swap)
  4. Monitoring and sample collection station for the environment (e.g. sensors to detect fire, crime, accidents etc.)

Complementing Nearby Mesh in the cities, Float Mesh is the new information super highway system for the countryside. It can improve many existing processes immediately, for example:

Float Mesh is made up of thousands of nodes working together, damage to a small number does not affect the operation of the mesh in general. Ownership of the Float Mesh is distributed amongst all occupiers of the land or sea that the Float Mesh nodes are located.

1.1 Lack of space in Space

Even before all its satellites have launched, Starlink is already accounting for half of all close encounters (less than 1km).

starlink

A terrestrial system like Float Mesh can reduce the need for a FEW companies using up a large chunk of near earth orbit (which belongs to ALL humankind) with tens of thousands of their satellites.

1.2. Too far away in Space

No matter how low a satellite fly (distances measured in kilometres), a Float Mesh balloon (distances measured in metres) is still a thousand times closer to earth.

Whether it is the power of the zoom lens or the strength of the radio signals, the quality of results from Float Mesh will always higher.

The high cost of accessing space put large constellations with more than 1000 satellites beyond the reach of most countries. Float Mesh changes that by giving countries, no matter how small, the ability to build their own large constellations in the sky.

1.2. Balloon Design

The Float Mesh balloon is based on the Kytoon design for stability in strong winds.

balloon_21m3

The above image shows the side of a balloon about 5 metres long by 4 metres wide with a lift capacity of 9 kilograms using 20 cubic metres of helium, which has the approximate size and lift performance as the Small Float Mesh Node.

The image below shows the front of a balloon about 8 metres long and 6 metres wide with 64 cubic metres of helium with 30 kilograms lift capacity, which has the approximate size and lift performance as the Large Float Mesh Node.

ballon_60m3

The above 2 sample photos are from Allsopp, we are currently NOT related to it but expect to work with it or another experienced balloon company to produce Float Mesh Nodes.

There was a proposal of using the Allsopp balloons to provide mobile phone signals in Australia. It was not successful, but the document give insight into the some of the thought processes involved.

2. Unique Features

Although Float Mesh nodes are based on tethered balloons, their designs have been substantially modified to allow them to work with the latest technologies like thin-film solar, hydrogen fuel cells and Unmanned Autonomous Vehicles (UAVs).

2.1. Hydrogen Gas

Unlike other modern balloon, we are designing with hydrogen instead of helium. We believe the scarcity of helium is not suitable for very large scale ultra low cost long term remote operation.

Hydrogen has superior lift than helium but is highly flammable when mixed with air, however for unmanned balloons high up and far away from population their flammability can be managed at low costs.

Float Mesh generates and uses the resulting hydrogen in place (on the balloon) so some traditional problems with hydrogen like transport and long term storage do not exist.

Generation

For initial launch if the balloon, helium can be used. After deployment, hydrogen is used to replenish any leaked gas using solar and wind powered hydrogen generators (e.g. electrolysis of recycled water from electricity generation and water extracted directly from air).

Generated hydrogen can be used by Float Mesh for

  1. Lift - to replace lost of lifting gas (hydrogen or helium) overtime, in order to maintain altitude the hydrogen generated must be large enough to cover any lost (which is about 1% per day for helium).
  2. Energy - to produce power using fuel cell when power from other sources (solar or wind) are inadequate.

If not enough hydrogen is generated to maintain lift, UAVs can be used to deliver 5% of booster helium approximately once every 5 days.

If not enough hydrogen is generated for energy storage, alternative storage like lithium battery can be used.

Using consumer technologies, online shops are offering flexible 300W solar panels at 1.7Kg and 300mL/min hydrogen generators at 150W. Those figures roughly cover the small mesh node's 138mL/min and large mesh node's 444mL/min gas replenish requirements.

With recent advancements in printable solar cells, carbon fibre turbine blades and low cost polymer electrolyte membrane (PEM) water electrolysis, we expect that there will be enough hydrogen generated by solar and wind to maintain lift indefinitely.

Containment

Metallised polyvinyl fluoride film with polyurethane coating is used for the envelope fabric to slow the escape of hydrogen gas and to reduce static discharge and sparking.

Some alternative materials may be possible e.g. graphene based membranes show promise of better confinement of hydrogen inside the balloon and is being investigated.

2.2. Hydrogen and Water Cycle

Float Mesh nodes uniquely use the hydrogen gas that is providing lift as storage of energy also.

Excess electricity create by the solar and wind generators on the balloon is use to generate hydrogen from water and the resulting hydrogen is stored inside the balloon as lifting gas:

Electricity + Heat + Water (2H2O) → Hydrogen (2H2) + Oxygen (O2)

This Hydrogen Generator is normally located at the BOTTOM of the balloon to let the generated hydrogen rise up easily into the balloon storage and to take advantage of the downward flowing of water from the Electricity Generator.

The hydrogen generator takes advantage of the heat as well as the light from the sun to generate extra hydrogen. Over sized wires from the photovoltaic cells carrying electricity and heat are passed through water tanks in a mesh to heat up the water for the hydrogen generator.

light_heat

The heat exchange also help cool the solar cells, which do not perform well at high temperatures.

When there is not enough light or wind to generate required electricity, electricity is generated using the hydrogen stored in the balloon and the oxygen in the air:

Hydrogen (2H2) + Oxygen (O2) → Water (2H2O) + Heat + Electricity

The Electricity Generator is normally located at the TOP of the balloon to let the generated water flow down easily to the Hydrogen Generator and to take advantage of the upward flowing hydrogen from the balloon storage underneath.

Although separate hydrogen electrolysis generators and hydrogen full cells are used currently, the newer regenerative fuel cells can be used for both processes in the future.

2.3. Multiple Gas Compartments

Separate compartments are used for storing hydrogen used for lifting (the compartment size remains somewhat constant and is normally situated at the core of the balloon) and for storing hydrogen used for energy (the compartment size can expand and contract substantially and is normally situated at the parameter of the balloon).

There are at least one compartment of each type. Depends on application, each type can have many more compartments. All compartments are independent of each other, so damage to one does not affect the others.

Electronically controlled valves in each compartments enable hydrogen to be let out and and air to be let in as required (e.g. to descend in a controlled manner or to adjust the balloon structure when circumstances changes).

2.4. Rapid Load Exchange

Float Mesh standard Unit Loads allows physical objects to be exchanged and stored in a standardised way. So upgrades like from WiFi 6 to WiFi 7 can be done quickly and at low costs.

There are 3 types of unit load containers: Packets inside Trays inside Pallets.

unitload

  • Multiple Pallets can fit inside an ISO Container optimally.
  • Each Pallet has a stack of Trays which can be slide out individually like a drawer to expose its content to a UAV.
  • An UAV can access the content as a packet via pick and place from above OR via drop and collect from above and below.

packetexchange

Drop and Collect method requires the UAV to fly both above the tray to drop the packet and then fly below to collect the packet. However the UAV design is simpler since there is no need for a mechanism to pick up the packet from the tray.

In both methods, the UAV provide physical guides (e.g. 4 small rods on the 4 sides of the packet exchange path) for pick, place, drop when UAV is above the tray and for collect when UAV is below the tray. The guides are retracted or lie flat during flight.

packetguide

The guides will take care of minor alignment problems, but it is up to the tray to make sure that it is as horizontal as possible. For example, having a hinge system at the end of the tray, so the tray can be maintained in an horizontal position by the Pallet or by the UAV.

Ultra Fast UAV Recharge

Using this rapid load exchange system to replace battery is substantially cheaper and faster than other UAV mid-air recharge solutions.

The Float Mesh node becomes a refuelling point for UAVs (where they can though drop off and pick up freshly charged battery).

Besides dividing the current battery from one into two (so one can be used during the exchange) and adding the simple drop and collect mechanism, there is no significant change to existing UAV design.

Combined with Float Mesh Node's WiFi capability, many new applications, like long distance delivery and non-stop crop dusting become possible.

2.5. Energy Sources

The high elevation of the balloon allows it to catch more sun light at dawn and dusk. Even the underbelly of the balloon can have solar cells attached to generate electricity.

Thin-Film Solar is now readily available online with continuous improvement being made. For example, locally in Australia we have exciting developments like quantum dots and printable solar cells.

Strips of thin-film solar cells are printed on or attached to most surfaces of the balloon (including the envelope and the kite). With solar strips on its surface we need to fold the balloon up is a special way so not the damage the solar cells, resulting in larger storage and transport volume than a traditional balloon of similar size.

The aerodynamics of the balloon means it is always pointing into the wind, so the use of small wind turbines to complement the solar array (e.g. during the night and on cloudy days) is complementary. Both horizon and vertical axis wind turbines can be attached the tether or attached to mount points on the main envelope.

2.6. Helicopter Deployable

The best locations to put Float Mesh Nodes might not have easy access, e.g. in the middle of the sea, on top of a steep mountain or covered by thick forest etc.

Claiming sovereignty of an area by deploying a Float Mesh Node does not take much more time than planting a flag but is substantially more useful.

Assuming an anchor has been prepared on the ground, the Float Mesh node has been designed to be deployed with a single helicopter within 1 hour of reaching the site.

helicopter

Only a few square meters of space is required on the ground for the anchor to be installed. Depending on the site, the anchor can be prepared before hand by a small team on an earlier helicopter flight.

anchor

Unlike other tethered balloons there is no need for a powered winch on the ground, the anchor has a weak string loaded retractable reel, which purpose is to get rid of slack on the tether instead of pulling the balloon down. The tether is made up of very light and strong non-conducting material (e.g. Dyneema).

On the day of deployment, the bottom of the tether is attached to the prepared anchor and helium gas is injected into the Float Mesh node via a valve on the top of the balloon. A metal ring around the valve allows a secure connection with the helium bottle to be made using the electromagnet.

A video camera on the helium bottle allows the whole process to be monitored from the helicopter. Once the helium injection has finished, power is removed from the electromagnet and the helicopter can fly away.

2.7. Service Procedures

Float Mesh node has been designed to be services mainly by UAV and helicopter while remaining in air. On rare occasions it can be brought down to the surface.

There are numerous eyelets on the tether cable and on the main envelope structure for a swarm of UAVs to attach themselves so they can work on the Mesh Node autonomously.

In order to the Mesh Node easily services by UAVs, major components of the Mesh Node are deployed as Packets inside Trays.

These Operation Trays (as oppose to standard Storage Trays inside Pallets) are standalone without Pallets holding them. They are attached to different parts of the envelope structure at different angles. A hinge and eyelet system allows them to be lifted to a horizontal position so Packets can be exchanged easily with the servicing UAV.

hinge

In situations where the vertical rapid load exchange cannot be used, more advanced UAVs can gain access by inserting and removing packets from the side of the tray.

sideinsert

Just like the normal vertically exchanged packets, these side exchange packets can have sizes up to almost the size of the tray itself, in this case one packet is stored per tray.

Although not normally necessary, in air refill with helium is possible using the same video camera and electromagnet process as in the initial deployment.

If the whole Float Mesh node needs to be removed or replaced while in air, a helicopter can attached itself to the top of the node via electromagnet, then deflate the node, detach it from the tether and fly away. The small parachute is deployed at the end of the tether to slow the descent, allowing the spring loaded reel to retract the tether properly.

If the Float Mesh node needs to be brought down to the ground, air bags (like those in cars but remain inflated) are deployed to protect important equipment and the valves in the gas compartments are opened to let the lifting gas out in a controlled rate. As the balloon descent slowly, the clamp on the anchor is opened to allow the spring loaded reel to take up any slack.

2.8. Safety

Float Mesh node will deflate itself when its has exceeded it operation hemisphere (defined by altitude, latitude, longitude). In case the retractable reel does not work, Float Mesh should not be deployed where there are human made structures within the radius distance around it as its operation height (length of the tether).

All pallets and packets have a safety cable connected directly to the tether cable, in additional to being attached to the envelope and its associated structure.

ballooncheck