Micro-Drones 2.0

The Bitcoin protocol allows adding metadata to Bitcoin transactions. This id done by adding another output with an OP_RETURN operator. The OP_RETURN operator signals the Bitcoin nodes that this output is not vital for Bitcoin transactions and will never be spent, so that they don’t need to store it.

The steps for putting a transaction containing meta data are as follows:

Get a Bitcoin address with a positive balance

Create an output Bitcoin address that will receive the transaction

Build the transaction

Transmit the transaction to the Bitcoin network

How much data can you put on each transaction?

Every transaction can have up to one OP_RETURN output according to the Bitcoin protocol. Each OP_RETURN output can contain up to 80 bytes of data, which is equivalent to 80 ASCII characters or 160 hexadecimal symbols.

Step 3 - Building the transaction

var bitcoin = require ('bitcoinjs-lib');

var tx = new bitcoin.TransactionBuilder();

var transactionId, //a transaction that has the unspent output

unspentOutputId, //the serial id of the unspent output in the transaction

inputKey, //the key that corresponds to the unspent output address

outputKey,//the key that corresponds to the recipient of the transaction

amount; //the amount to be transferred - should be the entire unspent output minus a reasonable fee

//Creating the OP_RETURN script

var data = new Buffer(”Your message here”); var dataScript = bitcoin.scripts.nullDataOutput(data);

DARPA (The US Defense Advanced Research Projects Agency) created an initiative to crowd source the development of the next generation of UAVs. Their goal with this initiative is to facilitate the exchange of ideas among the international community.

The website provides the platform for the teams to work collaboratively, design and develop in the challenge. Small business, hobbyists and students are especially encouraged to participate in the challenge.

A top manufacturing company will also be selected to participate in the challenge and provide the teams with insight and expertise.

Top teams will be invited to present their project and compete in a fly-off. The winning team will win a prize of $100,000, a subcontract with a manufacturer in order to produce a limited number of systems and an invitation to demonstrate their project in an exclusive operational military demo.

There are many technical specifications that the projects that participate in the challenge need to meet. The goal of the challenge is to provide a system that can fit in a backpack of a single soldier, vertically take-off and land, fly to the target area while avoiding obstacles, land in the target area and transmit video for several hours, fly back while avoiding obstacles, overcome a communication out, follow a moving target in real-time and come back and land safely.

The UAVForge challenge consists of 3 phases:

Phase 1:

Concept video - Competing teams are required to submit videos to advertise their skills, design sketches, algorithms etc. The teams that submitted the top ranked videos of this stage are encouraged to participate in the following stages.

Proof of flight video - The competing teams are required to demonstrate the early flight behaviors and capabilities of their system. Similarly to the first stage, the teams that submitted the top ranked videos of this stage are encouraged to participate in the following stage.

Live video demo - The competing team are required to participate in a live video demonstration of their system. Additionally, the teams must provide complete design information of their project for evaluation. The 10 top teams of this stage will be invited to the competition fly-off.

Phase 2:

Competition fly-off - The 10 top teams will participate in a live competition where they will be judged according to the Technical Performance Criteria of the challenge. The winning team will receive a $100,000 prize and the opportunity to demonstrate its project in an exclusive operational exercise.

Phase 3:

The manufacturer and the winning team will work together in order to fabricate up to 15 pieces of the project.

This video demonstrates the tracking of a target with a camera. The developers that took this video plan to use this algorithm in order to develop an autonomous accurate landing of a micro drone.

The developed algorithm finds the center of a pattern that is printed on the ground by using an on-board camera. By knowing the position of the center of the pattern in the picture, the micro drone can know its relative position to the center of the pattern, and autonomously maneuver in order to position itself accurately above the center of the pattern.

According to the video, the pattern is composed of 3 circles that form the 3 corners of a triangle. By identifying the 3 circles, the algorithm can calculate the center of the triangle.

A problem that this algorithm solves is the changing distance problem. Since the pattern should be recognized both from a height of several meters and from a height of several centimeters, the pattern is composed of several concentric triangles of different sizes and of different colors. When the micro drone is high above the pattern, it recognizes the big triangle. As the drone comes closer to the ground it recognizes the smaller and smaller triangles. In order to allow the algorithm to separate the different triangles from one another, each triangle has a different color.

This video presents a new control algorithm for the Mikrokopter platform.

While watching this video you might not notice anything different about this micro drone, but that's only because you don't see the remote that is operating the micro drone.

In order to understand the difference and the advantages of the new controls, we need to first understand how the "normal" controls work. Well, the position of the right stick in a "normal" remote tells the drone which roll and pitch angles it should keep. When the operator moves the stick, the drone tilts on its side, it accelerates and gains speed. If the operator wants the drone to stop, it need to tilt it back to the opposite direction, so the drone would decelerate and eventually stop.

It is already quite clear that these controls might not be the most simple controls when you need to move the sticks twice to move the drone from place to place.

So, what did they do?

What happens with the new controls demonstrated by this video, is that the right stick in the remote of the operator doesn't control the attitude angles of the drone, but rather the lateral speed of the drone. So, when the operator does not touch the right stick, the drone just stays in place. Not just keeps a neutral angle, but stays in place. And, in order to move the drone, all the operator needs to do is to move the stick in the desired direction, and return it to the center when the drone is in the right place. One move of the drone, one move of the stick. The operator uses the controls to control directly what he really cares about - the location of the drone.

The best improvement that this new control algorithm demonstrates is the altitude control. Usually, controlling the height is the most difficult part of flying these drones. That's because the force of the engines needs to be equal to gravity. If it's even a little bit stronger, the drone would eventually climb, and if it is slightly weaker, the drone would descend. Keeping a constant height is a difficult mission that requires a large part of the concentration of the operator.

Nevertheless, in the demonstrated control algorithm, when the left stick of the operator is centered, the drone magically holds its altitude. That's because the left stick does not control the power of the engine as for "normal" micro drones, but rather controls the climb rate of the drone. When the operator moves the stick up, the drone climbs at a constant rate. When the operator moves the stick down, the drone descends at a constant rate. And when the operator keeps the stick in the center, the drone keeps its altitude. Amazing.

Look how much easier the control of the drone becomes: If the operator does not move the sticks, the drone stays in place. The operator can be free to operate the camera, or whatever payload the drone carries. When the operator wants to move the drone, he just needs to move the sticks a little bit to the right, or a little bit to the left and not worry about the drone drifting away.

How did they do that?

Apparently, what they did is they used the accelerometers of the Mikrokopter and the pressure sensor, in order to estimate the lateral and vertical speeds of the Mikrokopter. They reprogrammed the flight control so that the remote control of the operator would control these parameters rather than the attitude angles and the power of the engines.

Why is that important?

It's important because current micro drones are not easy to use. They require a lot of skills and experience in order to be used safely, without causing damage to people, property or to the drones themselves. That means that if a company, for example, wants to use a micro drone today, it has to find a talented operator and invest a lot of time and money into his training. It makes using these micro drones very expensive. If we can make these micro drones easy to use, then we make them much cheaper to use, which will make them much more popular and it would allow micro drones to realize their true potential in the market.

That is not yet what we would like to call a micro drones 2.0, but it is definitely in the right direction.

The Canadian Aeryon Scout was used by the Libyan rebels.

While NATO countries fly unmanned aerial vehicles (UAVs) high above Libya, none of these UAVs, or the vital intelligence they provide, was available to the Libyans fighting to free their country – they were fighting blind. So, they got one of their own. It can now be disclosed that the Libyan rebels have been using the Aeryon Scout Micro UAV to acquire intelligence on enemy positions and to coordinate their resistance efforts.

These guys took it a little bit too far. We are talking about microdrones 2.0, but it seems like these guys are a better match for microdrones 5.0

Austrian research company IAT21 has presented a new type of aircraft at the Paris Air Show which has the potential to become aviation's first disruptive technology since the jet engine.

The D-Dalus (a play on Daedalus from Greek mythology) is neither fixed wing or rotor craft and uses four, mechanically-linked, contra-rotating cylindrical turbines, each running at the same 2200 rpm, for its propulsion.

The key to the D-Dalus' extreme maneuverability is the facility to alter the angle of the blades (using servos) to vector the forces, meaning that the thrust can be delivered in your choice of 360 degrees around any of the three axes. Hence D-Dalus can launch vertically, hover perfectly still and move in any direction.

Like most cars and aircraft these days, it sounds very complex but it's all controlled by an on-board computer, so the control is similar to the control of a helicopter or a quadrotor for the user.

D-Dalus is particularly suited for landing on moving vehicles such as boats since it has the ability to "glue down" on landing.

SUAS news introduced a concept called InvisiTower (as in "invisible tower"). The concept comprises of a quadrotor platform that is connected to the ground through an optical fiber that supplies all the necessary power and communication for the persistent flight of the quadrotor.

This video demonstrates an oil rig inspection by a micro-drone.

Similarly to the video attached to our previous post, this video demonstrates the challanges in inspection using current control technology, the highly skilled operator required to the machine, and the difficulties that even a skilled operator faces.

A demonstration of power lines inspection using micro-drones. This video demonstrates the potential in this technology for these application, but also demonstrates the difficulties and challanges of current micro-drones technology.

Seems like "The Daily" started using the AR Drone to shoot aerial photography.

Scandicraft has launched the ScanCam 200 - currently undergoing field testing in cooperation with the Norwegian Armed Forces.

Some more information about the ScanCam 200 can be found here: http://www.airforce-technology.com/contractors/uav/scandicraft/