Tag Archives: quadcopter

DJI Phantom 4

The DJI Phantom 4 is the new model in the popular phantom range of quadcopters, it has a number of improvements over previous models.

DJI Phantom 4

DJI Phantom 4

Comparison of DJI Phantom 4 and 3

Model Phantom 4 Aircraft Phantom 3 Professional or Advanced Aircraft
Battery 4S 15.2V 5350mAh Intelligent Flight Battery 4S 15.2V 4480mAh Intelligent Flight Battery
Max Flight Time 28 mins About 23 mins
Vision Positioning System 10m 3m
Obstacle Sensing System Optical Sensor – 0.7 – 15m N/A
Intelligent Flight Modes Follow Me
Point of Interest
Waypoints
Course Lock
Home Lock
ActiveTrack
TapFly
Follow Me
Point of Interest
Waypoints
Course Lock
Home Lock

Using the TapFly mode you can tap on a position of the screen in the app to fly to that location.

One of its main improvements is the introduction of obstacle avoidance technology (Sense and Avoid) using cameras mounted above the legs on the front of the Phantom 4.
DJI Phantom 4 - Obstacle Avoidance

DJI Phantom 4 – Obstacle Avoidance

The system, and the subsequent technologies, rely on a companion computer within the drone attached to the various sensors which uses computer vision algorithms to detect obstacles in the drones path. Once it has detected an obstacle it will either hover or fly around it.

DJI Phantom 4 - Companion Computer

DJI Phantom 4 – Companion Computer

It also comes with an improved Vision Positioning System, for position hold without the aid of GPS, which raises the positioning altitude from 3m to up to 10m.

DJI Phanton 4 - Vision Positioning

DJI Phanton 4 – Vision Positioning

A final important new technology is ActiveTrack where a subject can be selected in the app, and once again using computer vision technologies, the Phantom 4 will follow the subject even when it is turning.

DJI Phantom 4 - Active Track

DJI Phantom 4 – Active Track

The DJI Phantom 4 is available for £1,229.00 and will be on general release from the 23rd of March. As such it will be the first commercially available drone with obstacle avoidance technology.

Benefits

The Phantom 4 provides a number of cutting edge technologies on a low cost platform. The benefit of ActiveTrack has already been discussed in a previous blog – UAVs for site tour recording – Part 1 – Theory while the potential of the sense and avoid and vision positioning system technologies will be discussed in a future blog on building recording.

Drawbacks

The main drawback of the system is the fact that the camera is not of the same quality as the Zenmsue X5 which is available for the DJ Inspire 1 Pro/Raw. But even this camera is not of the same specifications as many standard DSLR or mirrorless cameras, only providing 16MP.

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Mirror-less Cameras and UAVs

UAV (Unmanned Aerial Vehicle) photography and photogrammetry has long been a balance between weight and the quality of the camera equipment carried.

Cameras

Low cost camera solutions such as the GoPro can be carried on almost all UAVs because they are small and lightweight, but these benefits are also drawbacks because limited size/fish eye lenses and small image sensors reduce the quality of the photographs they take, together with this the lack of control of many of the camera settings is a drawback.

High quality DSLR (Digital Single Lens Reflex) cameras have superior quality lenses and image sensors together with the fact that they have extensive control of the camera settings meaning that they take much better photographs. But they can only be carried by much higher power/cost octo and hexo-copter systems.

One solution is the lightweight point-and-shoot camera/compact camera used in some mapping solutions, such as those provided by 3DRobotics (Canon PowerShot S100). Although these cameras provide a better quality solution than the GoPro, and may be all that is required for mapping exercises; they are still limited in their optics and higher megapixel sensors which are much more important in the recording of complicated structures and photogrammetry work.

Changes in the camera industry due to competition from the phone industry has enhanced development of a different solution. This is the MILC (Mirrorless Interchangeable-lens camera) or DSLM (Digital Single Lens Mirrorless) Camera. These cameras don’t have the mirror reflex optical viewfinder of a DSLR camera, and the associated weight, replacing it with a LCD screen or with an app on a mobile device which controls the camera. As a result they have the capability to carry high quality interchangeable lenses without the weight associated with DSLR cameras. The system comes in two different forms; the first resembles a standard digital SLR camera, while the second resembles just a lens with all control being provided by an app on a mobile device.

Camera Comparison
Camera Type Megapixel Weight Cost
Canon EOS 5D Mark III Digital SLR 22.3 Approx 950g £2,544
Nikon D5300 Digital SLR 24.2 Approx 840g £549.99
Sony A5000 DSLM Digital SLM 20.1 Approx 388g £250
Sony ILCE-QX1 Lens Style Camera 20.1 Approx 332g £250
Canon PowerShot S100 Compact Camera 12.1 Approx 198g £195
GoPro Hero3+ Black Sports Camera 12 74/136g (with housing) £349.99
Canon EOS 5D Mark III

Canon EOS 5D Mark III

Nikon D5300

Nikon D5300

α5000 E-mount Camera

α5000 E-mount Camera

ILCE-QX1 Lens-Style Camera

ILCE-QX1 Lens-Style Camera

3DRobotics UAV Mapping Solutions, discussed in another blog entry, carry the Canon PowerShot S100 digital compact camera.

Canon PowerShot S100

Canon PowerShot S100

GoPro Hero3+ Black

GoPro Hero3+ Black

UAVs

UAVs come in a number of different configurations and increase in price with a higher level of complexity and ability to carry heavier loads.

UAV Comparison
UAV Type Payload Capacity Price (Without Gimbal)
3D Robotics Iris+ Quadcopter 400g £599
3D Robotics X8+ Octocopter 800g – 1Kg with reduced flight time £880
Spreading Wings S900 Hexacopter 4.7 – 8.2Kg £1,291-£1,540
DJI Spreading Wings S1000+ Octocopter 11Kg £1,750-£2,057
3D Robotics Iris+ Quadcopter

3D Robotics Iris+ Quadcopter

3D Robotics X8+ octocopter

3D Robotics X8+ Octocopter

Gimbals

Gimabls are an important element in stabilizing cameras during photography and video recording, as well as providing a motorized solution to move the camera to a desired angle during flight. They can add significantly to both the weight and price of any UAV solution depending on the camera equipment they are carrying.

Gimbal Price Comparison
Gimbal Camera Weight (Camera excluded) Cost
DJI Zenmuse H4-3D GoPro 168g £249
DYS 3 axis brushless gimbal Sony NEX size camera 388g £231.95 – £299.94
DJI Zenmuse Z15-A7 Sony α7s and α7r 1.3Kg £1,915
DJI Zenmuse Z15-5D III (HD) Canon EOS 5D DSLR 1.53Kg £2,831

Solutions

The 3DRobotics Iris+ Quadcopter has a payload capacity of 400g which would allow a rather small 15g for a mount to attach a Sony A5000 DSLM or 68g to attach a Sony QX1 Lens-Style Camera without weighing too much, although the system could be flown with excess weight reducing the flight time. A downward facing 3D Printed Sony A5000 Mapping Mount  is available for both the Iris+ Quadcopter and X8+ Octocopter, it weighs 36g.

Although the X8+ is a octocopter by definition, it gets over the intrinsic problems of size, weight and cost caused by eight separate arms by having two rotors on each arm, one pointing up and the other downwards. With a maximum payload of 1KG it can carry a Sony A5000 DSLM camera (388g) together with a gimbal such as the DYS 3 Axis Brushless Gimbal for Sony NEX size cameras (609g) to support and move it, the gimbal is designed for the NEX range of cameras, but they are almost identical to the A5000 in design. Although a lighter mount could be used.

3 Axis Brushless Gimbal for Sony NEX size cameras

3 Axis Brushless Gimbal for Sony Nex size cameras

Conclusions

The mirror-less camera would seem to provide a solution to the problem of how to carry a high specification camera capable of capturing high quality images on a fairly low-cost UAV solution.

Sources

http://en.wikipedia.org/wiki/Mirrorless_interchangeable-lens_camera

http://www.dummies.com/how-to/content/gopro-cameras-understand-the-cameras-limitations.html

http://www.japantimes.co.jp/news/2013/12/30/business/mirrorless-cameras-offer-glimmer-of-hope-to-makers/

Quadcopter vs Hexacopter vs Octocopter: The Pros and Cons

Kickstarter UAVs

With the change in the way that projects are funded a number of drone/UAV (Unmanned Aerial Vehicle) systems have been funded on Kickstarter, these systems are generally designed to fill a perceived gap in the market providing everything from wildlife conservation to tornado research.

A number of these have innovative technologies which can aid in the recording of archaeology/cultural heritage.

This blog entry will be an evaluation/comparison of these various systems, charting their speifications and abilities to help with archaeological and cultural heritage recording.

Kickstarter Drone/UAV Flight Specifications
Name No. of rotors Control System Flight time Autopilot Cost
AirDog 4 App and AirLeash 10-20 mins Pixhawk $1,295 – $1,495
Anura Pocket Drone 4 App 10 mins Unknown $275
Easy Done 4 RC Controller 12-16 mins Based upon APM 2.6 $985 – $1,545
HERO+ 6 App 15 mins Pixhawk $949.00 – $1,149.00
Incredible HLQ (Heavy Lift Quadcopter) 4 ? ? APM2.5+ ?
MicroFly 4 Computer wi-fi ? ? ?
Phenox 4 Voice and gesture 5 mins Voice and gesture controlled and programmable ?
RObot 4 also 4 wheel rover RC Controller ? None ?
The Pocket Drone 3 RC Controller / App 20 mins Pixhawk $549 – $599
ZANO 4 App 10 – 15 minute Unknown £169.95

Kickstarter Drone/UAV Payload/Sensors Specifications
Name Camera Gimbal Other Mounts Sensors/Other abilities
AirDog GoPro 2 or 3 Axis None
Anura Pocket Drone 720×1280 HD camera None None Fits in pocket
Easy Done GoPro – can lift heavier cameras None None Modular
HERO+ GoPro 2 or 3 Axis 360 Cam
Incredible HLQ (Heavy Lift Quadcopter) None, but can carry 50 pounds None None
MicroFly None None None None
Phenox 2 cameras to recognise the controller None None Range sensor
RObot None None None None
The Pocket Drone GoPro None None Collapsible compact design
ZANO OV5640 5MP camera None None Swarm capability

Conclusions
The obvious conclusion can be drawn that the GoPro camera is the single most popular camera for use with UAVs due to its size and capabilities. But of equal popularity is the series of open source autopilot systems designed by 3D Robotics (APM and Pixhawk), this demonstrates the quality and abilities of these products.

It could be suggested that the bubble has at least partially burst on the funding of UAV (Unmanned Aerial Vehicle) projects on Kickstarter from the number of new projects that have failed to reach their funding goal recently. Although some Kickstarter projects are probably not funded due to the fact that they bring nothing new to the area of UAVs, some others appear to have innovative ideas and still receive little funding.

The potential of autopilot follow-me technology for the recording of site tours has been discussed in the reviews of the AirDog and HEXO+ systems. The swarm capabilities of the ZANO system brings forward the possibility of multiple UAV systems recording the subject matter from multiple different angles at the same time allowing the recording of significantly more visual data than a single UAV.

New developments have been used to control the position of the done and the ability to avoid obstacles including ultrasonic distance measurement.

The micro and nano drone systems provide a means of recording a subject with systems that, in one case can fit in a pocket and otherwise, can be easily portable and taken to the subject that requires recording, even recording tight shaft trenches with a system that has ultrasonic distance detection technology keeping the system away from the edges of the metal sheet piles.

Ghost Drone

The Ghost Drone is a wind and rain resistant Indiegogo project drone aimed at filmmakers, photographers, sports enthusiasts, travelers and adventurers, GoPro owners and first time and experienced drone pilots.

It is controlled by a smartphone app (either iOS or Android operating systems) where you can click on a map and the drone will go to that position; the map can be downloaded in advance. The app also has a number of one-click commands including take off, hover, return and land. Two sliding bars can be used to control the height and orientation of the drone; while another two control the camera gimbal with one tilting the camera up and down while the other pans it left and right. It’s micro control feature allows more precise movement of the drone over small distances. The Auto-Follow mode keeps the drone following the smart phone. If the drone exceeds 0.6 mile limit or the signal is lost it will return to its place of origin.

The app communicates with the drone via a G-box system, with the app communicating with the G-box via bluetooth while the G-box communicates with the drone via a wireless radio.

Other developments at higher Indiegogo targets include integration with a waterproof smartwatch and controlling the drone by tilting the smartphone, while obstacle avoidance will be available in future versions.

  • Up to 20 mins flight time with the gimbal
  • 10 mph (restricted) flight speed
  • Up to 0.6 miles control distance
  • Wind resistance up to 21 knot (11m/s)
  • iOS and Android apps
  • Propeller protectors

The Ghostdrone comes in 3 seperate versions, only two of which have a camera gimbal:

  • Ghost Basic (£430) – No camera gimbal.
  • Ghost Aerial (£550) – 2-axis gimbal designed for GoPro and similar cameras.
  • Ghost Aerial Plus (£559) – 2-axis gimbal and Ehang Sports camera.

An RC controller can be purchased for an extra $99. Another optional extra are prop guards to protect both the system and what is may be flying near, and photos on the site seem to suggest that the mini legs attached to them can be used to replace the main landing gear, this would allow a greater field of view.

Potential
The Ghost Drone is marketed as the easiest done to fly, and the flight controls within the app will certainly enable many autonmated movements with one button click.

The propellors of the system are pointing down rather than up (unlike other systems), this is believed to provide more stable flight.

The fact that the Ghost Drone is wind and rain resistant means that is can be used in conditions that would ground other systems.

As with other systems, the follow-me technology will allow the easy recording of video site tours.

The Ghost Drone comes with an SDK (Software Development Kit) which has already been used by one of the users to create voice interface which can be used to control the drone.

Limitations
The Ghost Drone is limited to the abilities of smaller cameras.

The system does not come with an RC controller, although it is an optional extra for $99.

Although you can purchses prop guards the manufacturer suggests removing tham during filming as they destabilise the system in flight.

Zano

The Zano is a Kickstarter project Nano drone.

Amongst its features are:

  • 5 megapixel HD video camera
  • IR obstacle avoidance
  • Echo sounding sonar and high resolution air pressure sensor for altitude control
  • Follow me
  • Bidirectional motor control (Zano can drive motors in either direction)
  • iOS and Android compatible app
  • 10 – 15 minute flight time
  • 15 – 30 meter optimal operating range
  • 25 mph top speed
  • Can fly in “Free Flight” mode, using on-screen Joy Sticks). On screen slide bars control rotation and altitude
  • ZANO will hold its position unless instructed otherwise
  • Tilt control of the Zano using a smart device
  • Automatic return to smart device

Other project developments include:

  • Tracking of a set target through image processing
  • Facial recognition capability
  • 360 and 180 degree Panoramics
  • Swarming capability

The app will also allow the purchase of future developments of the system.

The ZANO will cost £169.95.

Potential
It’s different technologies allow number of different applications including site tours and recording videos of sites. The swarming capability opens up the possibility of recording sites with a number of different drones at the same time. While it’s size makes it very portable and easy to use in confined spaces allowing the recording of areas that other drones may not be able to reach.

It comes with a with two part SDK (Software Development Kit) which allows development of apps using the core functionality of the drone and even control of the system using a VR headset.

Limitations
It’s camera is quite low quality so the photographic/video results may not be high quality.

DJI Inspire 1

The DJI Inspire 1 is the new quadcopter by the DJI company, this company is at the forefront of commercial innovations in UAV technology and the Inspire 1 brings a number of new technologies to the market.

One of these innovative design elements is that the rotors and legs can be lifted during flight allowing a full, unrestricted 360⁰ below the camera, this unrestricted view is common in much more expensive systems.

An option that is used in professional videography is dual-operator control, this is where one operator flies the UAV while the other controls the camera via the gimbal controls, with each operator having their own screen. The Inspire 1 has this option with the ability to buy two remote controls with the system as well as the technology within the drone.

Another innovative technology is the Optical Flow Technology which allows the location and altitude of the Inspire 1 to be maintained accurately even when a GPS signal is not available, such as an indoor environment, and allows the legs to automatically be lowered when landing. While the Vision Positioning System allows the system to hold its position while indoors, stop when the controls are released, and respond to your commands using a camera and ultrasonics system.

The DJI mobile app is available on iOS and Android and allows manual control of the camera, provides flight telemetry data and auto takeoff and landing controls.

The DJI Inspire 1 specifications are:

  • Hovering accuracy with the GPS mode of 0.5m vertical and 2.5m horizontal
  • Maximum Angular Velocity – Pitch: 300°/s and Yaw: 150°/s
  • Maximun Tilt Angle: 35°
  • Maximum Ascent Speed: 5m/s
  • Maximum Descent Speed: 4m/s
  • Maximum Speed: 22m/s (ATTI mode, no wind)
  • Maximum Flight Altitude: 4500m
  • Maximum Wind Speed Resistance: 10m/s
  • Maximum Flight Time: Approximately 18 minutes

The camera specifictions are:

  • 12 megapixel photographs
  • Video in 4K at 24-30 fps, or 1080p at 24-60fps
  • Lens with 9 elements in 9 groups including an aspherical element
  • 1/2.3 inch CMOS sensor
  • 94⁰ wide-angle FOV (Field of view)
  • 3-axis, 360⁰ rotating gimbal

The video from the camera can be displayed in real-time in 720p HD on mobile devices thanks to DJI’s Lightbridge technology which can transmit video up to 2km.

The modular payload systen of the Aspire 1 suggested that there are planned options for other recording media.

The camera can be detached and attached to a pole making the camera a handheld recording device.

A SDK (Software DEvelopment Kit) has allowed outside company integration with both the camera and software.

The Inspire 1 costs £2,380 with one remote control and £2,749 with two remote controls.

Potential
The Inspire 1 is a complete ready to fly system.

A constant problem with cheaper UAV systems is the fixed nature of the camera, with gimbals only being able to pan up and down generally because of the position of the legs of the vehicle. More expensive systems have legs that can be lifted upwards by motors allowing the camera to move 360° from side to side meaning that a separate camera operator can control the camera while the pilot concentrates on the flying, but these tend to be very expensive (£5000-7000 or more) and still require the additional purchase of a camera. The Inspire 1 gets around this problem by designing a system which lifts the legs up at the same time as the props giving this 360° degree field of view.

The Optical Flow Technology allows the Inspire 1 to fly indoors with stability when there is no GPS signal to stabilize the system.

Thanks to these abilities the Inspire 1 has the ability to both map archaeology and cultural heritage by taking vertical overlapping photographs from above in a mapping pattern, to record upstanding monuments with the camera at a right angle to them, and to record flythroughs of both archaeology and cultural heritage with a separate controller panning the camera when required. Unlike other systems it provides all of these abilities in one package.

The ability to carry other recording packages in the future is very enticing, hopefully including lidar and infra-red.

Limitations
On the face of it the cost would seem too high, but after analysing what you get (see the article on RC Geeks), for full details it becomes quite reasonable.

  • It comes with the DJI Lightbridge technology which would cost an additional £999 is purchased separately.
  • To equip a previous UAV with the 4K camera technology would require the purchase of a GoPro Hero4 Black which costs £369.99.
  • The Zenmuse H3-3D Gimbal to hold the camera would cost an additional £249.

So even buying the DJI Phantom 2 for £499 the additional costs to provide similar abilities to the Inspire 1 bring it close to the cost of that system, and that is without many of the abilities that the Inspire 1 has.

Although the Inspire 1 is pricey it comes with everything that you could need for professional style photography.

With the incareased movement of the many elements of the Inspire 1 there may be problems with wear and tear on the system.

News – 3D Robotics announces partnership with Intel

3D Robotics has announced a partnership with Intel in which they will be using the new Intel Edison for development of their autopilot systems. The Intel Edison is a microcomputer the size of a postage stamp which provides the power of a personal computer.

The extra processing power of the Edison will allow a person or object to be tracked with the follow me technology of the Pixhawk autopilot. So a person can be filmed automatically with the camera on the UAV (unmanned aerial vehicle) by tracking the person without the need for them to carry a mobile device, with its reliance on a less accurate GPS signal, as the UAV will be able to visually recognise a person.

It will also allow developments in image processing, sense and avoidance with new classes of sensors allowing further developments of autonomous UAV flight and object avoidance.