Draganfly Innovations releases their latest UAV helicopter, the Draganflyer X4. Several hundred hours of research and development went into its design, bringing about a sleek, sophisticated  UAV RC helicopter, available to more people than ever. The Draganflyer X4 features much of the same technology as the Draganflyer X6, but is available at a fraction of the cost. Designed for commercial, government, and military applications, the Draganflyer X4 RC helicopter provides affordable aerial photographs and video surveillance.

Diverging from the Draganflyer X6’s larger 6 rotor design, the Draganflyer X4 features the same quad rotor design used by older RC helicopters. Four brushless motors independently drive four carbon fiber rotor blades, all controlled by an advanced flight computer.

The flight computer uses SteadyFlight technology to process the inputs of seven individual sensors, including:

• A barometric pressure sensor
• Three accelerometers
• Three gyroscopes

The avionics computer reads sensor outputs and precisely determines the motor speeds required to keep the helicopter flying straight and level. If selected by the pilot, a barometric pressure sensor is used by the helicopter to maintain altitude. Properly trimmed and balanced, the helicopter will hold its position in the air allowing you to do excellent aerial photography and videography.

Four different cameras have been customized to work with our latest RC helicopter, including:

• A 12.1 MP digital still and video camera
• A micro color video camera
• low-light black and white video camera
• A FLIR (Forward Looking Infra Red) video camera

These cameras transmit wireless video via a 5.8 GHz radio transmitter built into the mount. Wireless video can be received using either the handheld controller (which includes its own flat patch video antenna) or the video base station. HD Video glasses plug directly into the handheld transmitter, allowing you to see what the helicopter is seeing and get perfectly aimed aerial photographs and video. The video base station is compatible with any modern PC running Windows and features three standard RCA output jacks. This allows you to use your own recording equipment with the cameras or even broadcast the video stream if needed.

Because all wireless communication is subject to interference, all of our cameras now feature a built-in DVR that records a pristine, interference-free copy of your aerial video to an SD card. After you finish flying, plug the SD card into your computer and edit the video using the software of your choice. Each camera also features a custom designed mount with a remote tilt feature. Designed to give you the best quality video possible, each camera mount features balanced, oil-filled shock absorbers. The shock absorbers keep the recorded video free from vibration, guaranteeing that you get the best possible results.

The Draganflyer X4 UAV helicopter features an innovative case system that makes transporting the helicopter easier than ever. The entire Draganflyer X4 helicopter presses neatly into its pre-cut slot in the case. Each part and accessory fits into molded high-density foam inserts for safekeeping during transport. The transport case features a dual layer design with flight accessories in the top layer and the base station in the bottom layer. A patented, load-bearing system clips on to the transport case allowing it to be worn like a backpack. Made from flexible Cordura™ nylon, the load-bearing system is securely attached using Fastex™ hardware and adjustable straps.

The entire transport case fits neatly into an ATA (Airline Transport Association) certified hard case, rated to last over 100 flights as airline baggage. The padlockable, all-metal, carpet-lined ATA case allows you to safely transport the helicopter anywhere in the world without worrying about damage caused by the rigors of airline travel.

Designed for small enterprises and projects on a budget, the Draganflyer X4 is one of the most affordable UAV RC helicopters ever. Use the power of a full featured UAV RC helicopter for your project – the Draganflyer X4 makes professional quality aerial photographs and video easier to obtain than ever before.

For the past several years, Mark Sharpe of the Ontario Provincial Police force has been using aerial pictures and video to help with law enforcement. From homemade devices made from commercial electronics to hobby aircraft with cameras, he has saved the police department approximately $20,000 in aircraft charter costs. Working with makeshift equipment helped the OPP greatly, but with today’s world issues and a vast area to patrol, they began looking for something more.

The OPP found a solution with the Draganflyer helicopter, North America’s first commercially available UAV legalized for law enforcement applications. Fast deployment and an advanced autopilot make the Draganflyer UAV the perfect choice for police departments who need aerial pictures and video.

So why would a police force based out of a small city need aerial surveillance? For one thing, the Ontario police need to cover a huge area ranging all the way from the U.S border to Hudson Bay. It is hoped that using remotely operated vehicles can help reduce charter costs to remote areas. Aerial pictures and video are also very useful in court, helping judges and juries to visualize crime scenes effectively.

Featured on www.canada.com, the Winnipeg Free Press, and the Saskatoon Star Pheonix, it’s clear that there’s definitely a market for UAVs in law enforcement applications.

All RC  helicopters are controlled by servos – small, electrical devices that allow controlled flight. So what are servos? How do they work? And how do you choose the ones that will work best in your model? We’ll answer all these questions, and show you how these amazing devices work.

Servos In General:

A servo is a device rotates a shaft to a position set by the user, and holds this position until further input is given. Servos usually consist of a small DC (direct current) electric motor, several gears, and a head where an arm or wheel can be attached. When the user tells the servo what angular position to move to, the servo rotates and holds position until further input is specified. Servos are designed to hold position because external forces are always interacting with the aircraft, and would set control surfaces to undesired positions unless stopped. Servos exert a torque on external forces, that prevents them from changing the position of any control surface.

How RC Helicopter Servos Work

A servo’s job is to convert the angular movement of a servo arm to the linear movement of a control surface. This is done by attaching linkages, called control rods to the servo arm and the associated control surface. When the servo head rotates, it pushes the control rod back and forth. The rod is linked to a control surface, and can move it up or down as the servo rotates.

Three wires control a RC helicopter servo: two to provide the DC electricity that the motor needs, and one that sends the signal, controlling the servo. The signal wire works by sending the servo a series of pulses, which are interpreted by it’s internal circuitry. By varying the timing of each pulse, the servo knows exactly which position to move to.

Choosing the Right RC Helicopter Servo

Servos have a number of qualities that make them suitable for different applications:

• Torque – This is a measure of the servos “strength”, or how much “push” it has. Torque is the product of force and the radius at which it acts, or the . This is shown graphically in the figure on the right. Bigger planes need high torque servos to move their large control surfaces. In general, servo size goes up with rated torque.
• Speed - Speed measures how fast the servo can move from one position to another. Different RC airplanes and helicopters will need servos with different speeds. For example: a trainer doesn’t need to change control surface positions rapidly, but a 3D helicopter or plane does. High speed servos are many times more expensive than standard ones.
• Dimensions – As stated previously, the dimensions of a servo increase with the torque that it provides.
• Weight – The weight of a servo depends on several variables. Most often recorded in grams, the weight of a servo is always reported on the package.
• Bearings – There are two ways to support the output shaft of a servo – bearings and brushes. Brushes are cheaper, but bearings last longer and operate more smoothly. Very small and very cheap servos tend to be brushed, while high end and very large servos generally have bearings. It’s possible to upgrade a brushed servo to bearings, with several upgrade kits being available on the internet.
• Gears – Most hobby grade servos use nylon gears, while higher end servos use metal gears. Metal gears add more weight, but their advantage is that they can’t “strip”, causing an RC helicopter or airplane to crash. Metal gears wear over time, which can cause “slop” in their rotation, but the gears can be replaced somewhat economically. In general, nylon servos are adequate for sport flying. If you’re particularly worried about losing a model in a crash, or are flying intense aerobatics, a metal geared servo could be the right choice.

Digital Vs. Standard RC Helicopter Servos

Servos can be of two types: digital, or standard. Both digital and standard servos can be used with a normal receiver, the real difference is performance.

All servos use a series of short pulses as signals that determine what angular position they should maintain. The series of signals is usually very fast, somewhere around 50 pulses per second at maximum. On a standard RC helicopter servo, the rate is so fast that very small movements of the control sticks may not have an affect. This means that there is a “deadband” on the control sticks, in which no servo movement takes place. Although it’s not a problem on trainers and most sport class models, the deadband becomes a significant issue with 3D aircraft. Even a small delay with a 3D aircraft could cause a severe crash.

Digital servos remove the deadband by speeding up the rate at which it receives pulses. Usually, this is increased from around 50 to 300 pulses per second. This increase in resolution allows the servo to operate much more precisely.

RC Servo Motors

The motors that drive RC servos come in several different types. Here’s a list of the most common varieties, and some information on each to help you decide which ones to use:

• Coreless – Conventional electric motors use copper wires wrapped around metal cores to form electromagnets. In a coreless motor, there is a metal mesh that rotates around the permanent magnets. Coreless motors respond more quickly than conventional motors, because they don’t have to overcome the momentum associated with heavy metal cores.
• Brushless – RC helicopter Servos can be powered by brushless motors, giving them longer life, faster response time, and more torque.
• 3 Pole and 5 Pole – DC Electric motors have permanent magnets, called poles, that electromagnets are attracted to. Servo motors can have either 3 or 5 poles, with more poles providing better torque. If you’re new to RC or have a regular sport model, you probably won’t notice the difference between 3 pole and 5 pole servos.

YouTube has collected quite a few crazy RC helicopter videos over the years, and some of them border on unbelievable. Here’s a few of my favourites:

RC Helicopters Fishing

I wouldn’t recommend trying this – you could easily lose your RC helicopter in the drink. Nevertheless, this is an amazing video. It looks like the pilot’s added floats to his heli, just in case he catches a really big fish!

Ultimate 3D Flying – Insane Tricks With RC Helicopters

Here’s a really cool one, that shows what’s possible with a 3D RC helicopter and really great flying skills.

RC Helicopter Crashes Volume 2 – Who Doesn’t Love A Little Destruction?

Every once in a while, it’s cool to see some spectacular crashes. This type of thing happens to everyone – here’s a compilation of some of the worst crashes ever seen! When RC helicopters crash, destruction is usually very quick.

We’ve shown you how RC helicopter jet engines work, but how do you use them to power RC helicopters? After all, jet turbines spin at extremely high speeds. Converting this rotation to a rotation of the main rotor blades isn’t very simple, and we need some cool technology to do the job. There are basically only two ways that an RC helicopter can use the high speed motion of a jet engine to power the rotors – here’s how they work:

RC Helicopter Direct Drive Turbines

RC Helicopter jet engines spin their axels at far to great a speed to directly hook up to the rotors, so the most obvious way to slow them down is a gear box. In the direct drive design, the turbine shaft is directly connected to a gear box, which slows down it’s rotation speed and powers the main rotors. This is the most obvious and simple design, but it has a few problems that have caused another, more sophisticated one to gain popularity. For example:

1. All the thrust produced by the jet engine is wasted. Because the only work done by the engine comes from it’s main turbine shaft, all the thrust from the engine is left unused. The thrust from the engine is usually channelled outside the RC helicopter.
2. The wasted thrust can lead to unwanted motion. RC jet engines produce a lot of thrust, and forcing it outside the RC helicopter creates unwanted forces that have to be cancelled out.
3. Direct drive jet RC helicopters are very inefficient. Only 20% of the total power produced by the rotor blades actually goes into turning the rotor blades.

With all the problems present in direct drive turbines, most jet RC helicopter enthusiasts are turning to another design:  two stage turbines.

RC Helicopter Two Stage Turbines

Two stage turbines use the thrust produced by the engine, instead of simply venting it as exhaust. Recall that a jet engine has a main turbine shaft, which is used to compress air and keep the engine running. A two stage turbine leaves the first shaft free to spin, and then adds an additional turbine to the end of the engine, where the exhaust is emitted and thrust is produced. The second turbine spins another shaft, which then drives the gearbox that powers the main rotors. What’s the benefit of using two turbines instead of just one? There are actually quite a few:

1. A two stage jet engine is about 80% more efficient than the direct drive design.
2. Less thrust is wasted, so there are fewer unwanted forces caused by venting it.
3. The engine has to carry less load. Overall, it’s better if the jet engine doesn’t have to directly power anything. Harnessing the thrust produced by the engine reduces vibrations and wear.

The only problems with the two stage design are that two stage turbines tend to be heavier than their direct drive counterparts, and they’re also a little more expensive.

A lot of people would like a way to make the Blade MCX RC helicopter fly faster – here’s how to do it with minimal modification and only a few basic tools. Do this mod at your own risk.

1. Remove The Flybar – The first step is to remove the flybar. Snap off the linkage that connects the flybar to the upper rotors, and pull the flybar out of the plastic linkage that holds it.
2. Remove the Old Weights – Using a pair of wire cutters or needle-nose pliers, remove the cylindrical weights found on the ends of the flybar. Make the cut right near the end of the flybar.
3. Add Lighter Weights – Some small beads, like those found in craft stores can be used to make new weights for the flybar. find small beads that weigh about 0.2 grams. Thread two beads onto each end of the flybar, and secure them with CA glue and heat shrink tubing. This picture shows the new flybar weights.
4. Re-Install the Modified Flybar – Put the flybar back on the helicopter.

And that’s all that there is to it! The lighter weights on the flybar reduce the RC helicopters stability slightly, but also make it more responsive to control inputs. You can also try adding a bit of weight to the nose to make the helicopter go faster.

Credit for this idea goes to the author of this rcgroups thread.

Vertical 911, a publication dedicated to the usage of rc helicopters in the EMS, law enforcement, fire and search an rescue sectors, has recently featured and article about our Draganflyer X6. The article notes the UAV’s applications to policework and usage by the Ontario Provincial Police (OPP) .

Vertical Magazine is the helicopter industries “insider” publication, featuring commentary by some of the industries leading voices. Although they usually feature full scale, piloted helicopter applications, our 1 kg UAV’s features were unique enough to write an article about.

The OPP became the first police service to use RC helicopters for forensic purposes inside city limits. You can learn more about Draganflyer X6 RC helicopters at www.draganfly.com

On the outside, the Prox Dynamics PD-100 looks like a standard, 2 channel RC helicopter. Looking at it’s flight capabilities and design show that this is not the case. The Prox PD-100 is a stabilized, tiny, and silent RC helicopter which can carry a camera payload. Weighing only a few grams, the PD-100 has obvious applications in police and military work, and can apparently reach a top speed of over 20 miles per hour. The PD-100 also has some sort of autopilot that allows it to actively compensate for wind, and it’s creators report that it can handle outdoor wind speeds fine. This is a surprising feature, because most micro RC helicopters are for indoor use only.

One of the PD-100’s coolest features is a transmitter with an integrated LCD display. The display shows images gathered from the camera and flight data. The transmitter also logs flight data and can interface with a computer. We expect to hear more about the PD-100’s features by it’s release date in 2010.

The PD-100 isn’t being manufactured yet, but Prox Dynamics expects to start shipping to customers by 2011. No price has been released yet. You can watch the video below to get an idea of how it flies.

Turbine RC helicopters are RC helicopters powered by jet engines. Nothing quite compares to seeing one of these monsters power up at the flight field, hearing the jet engine come up to speed and start to spin the rotors. Although they’re not very common, mostly due to the enormous cost of running a model jet engne, RC turbine helicopters are some of the coolest machines around. In part 1 of this article, we’ll look at how model jet engines work in general, and then move on to their application to RC helicopters.

How RC Helicopter Jet Engines Work

So how to jet engines work? They’re not actually that complicated, its the precision machining and temperature tolerances that make them expensive. On the most basic level, RC helicopter jet engines work the same way that full size jet engines do. Air enters the jet through an intake, is compressed and mixed with fuel, and then ignited, producing thrust and spinning a turbine. The turbine is connected to the compressor via a shaft, starting the process over again. Air is compressed in the engine because it increases the thrust obtained by burning the fuel air mixture. The end result of this whole process is a lot of hot air travelling out the back of the jet engine at a great speed, which results in thrust.

How does this process get started? After all, if the fuel / air mixture is burnt in the engine, shouldn’t the resulting air flow be able to go out the front and the back? The answer is simple: the jet engine compressor has to be spinning at a speed high enough to create enough pressure at the front of the engine to force the airflow out the back. In order to do this, the engine has to be spun up before starting. This is done by either blowing hot air into the front of the engine with a leaf blower, or spinning it up with a high speed electric starter. In some cases, jet engines have these electric starters built in. There’s only one more problem: in order to combust, the fuel must be in a gaseous state. Kerosene, the most commonly used jet fuel, is liquid at room temperature. To solve this, propane is used as fuel when starting the engine. Propane is a gas at room temperature, so it can enter the engine and combust right away. Once the engine is hot enough, the propane is turned off and the kerosene introduced.

Once started, we need some way to control the jet engines thrust. This requires precision control of the amount of fuel entering the engine, handled by a device called the ECU – engine control unit. The ECU is just a small computer that controls and monitors various engine functions, including:

• the turbine speed, usually measured in RPM (rotations per minute)
• the throttle command from the transmitter
• the fuel pump’s battery voltage
• the exhaust gas temperature (EGT)
• the total engine run time

Jet ECUs usually have a number of advanced features and fail safes built in for safety.

In  the next article, we’ll look at how RC jet engines are used to power RC helicopters.

Another addition to the seemingly endless variety of 2 channel indoor RC helicopters. the Havoc Stinger flys and performs similarly to other RC helicopters. The only change that we can see is that the Havoc Stinger has an insect look, with glowing LED eyes.

• Comes in three different colors, green/purple, yellow/orange, and blue/orange
• Uses A 50mAh 3.7V Rechargeable Lithium Polymer Battery
• Battery Charge Time: 15-20 minutes
• Flight time: 5-9 minutes
• The battery charger is built into the transmitter.
• Compatible with standard mini helicopter parts

All the standard mini helicopter modifications can be done with the Havoc Stinger. Add weights to the nose or tail to make it go forwards or backwards more quickly. The Havoc Stinger is not a knock-off, and was made by the same company that makes the successful PicooZ RC helicopter.