Monthly Archives: June 2013

Film making fifty Quadrotors Put on Glowing Sky Show

Original source from: http://www.aec.at/futurelab/en/referenzen/kategorie/kunst-am-bau/spaxels-klangwolken-quadrocopter/
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The Ars Electronica Futurelab—Linz’s proving ground of the future, a high-profile player at the nexus of art and science—is making big-time waves with yet another extraordinary development.

This article describes how the endeavor began, who and what were behind this sensory experience, and where the trip is headed next.

More videos on Youtube

“A conceptual spark alone doesn’t ignite a wildfire,” said Horst Hörtner, director of the Ars Electronica Futurelab and the project crew’s chief drone pilot. Intensive research on UAVs (unmanned aerial vehicles) led to contact with the leading institutions in this field: the ETH–Swiss Federal Institute of Technology Zurich (ETH-Zürich) and the University of Pennsylvania’s GRASPlab. Lengthy telephone conversations with staffers at both facilities as well as with Joe Paradiso of the MIT-Medialab led to the initial assessment that the undertaking was not doable in the allotted time and with the available budget.

But the idea had its hook in deep. Tenacity and complete confidence in the technical excellence of the Ars Electronica Futurelab fueled its progress. The whole thing seemed to be far out of reach the first time Hörtner presented the idea to his staff. Already on board was his quadrocopter model of choice—the Hummingbird by Ascending Technologies.

At this point, momentum started to pick up—first, by getting in touch with Ascending. Daniel Gurdan, Ascending CEO and head of development: “The first time I heard about this inquiry, I figured this was the pipe dream of some kind of nut job. But when they displayed persistence and were still discussing the same plan the third time they contacted us, it was clear that they were really serious about this!”

The Linz crew’s level of commitment was underscored by the presentation of the first swarm simulator during one of the visits. Under the direction of Florian Berger, the crew developed a system capable of realistically coordinating the flight behavior of 50 of these quadrocopters including correcting for any position determination errors attributable to the GPS. Thus, the details of how to implement the idea were emerging:

There would be a ground command station (flight control) that communicated with each individual drone. They would all be constantly sending data about their current position, and flight control would react in real time to deviations from the ideal course. Each movement is thus specified by this server and all sequences of movements continuously checked to prevent collisions. If need be, the server could intervene to correct a flight path, recalculate all position data, send this revised data to all individual drones, etc.


Fotocredit Gregor Hartl

Andreas Jalsovec and his group developed a method of configuring the flight behavior of the swarm. The result was a 3D Studio Max grid in which—like in any 3D animation project—an unlimited number of points could be designated

The results of the animation including all of the light values were first input to the swarm simulator where they could be evaluated in WYSIWYG mode. This simulator’s user interface served as the basis of the flight control engine, the server that navigated the swarm according to the specifications of the design team’s animations. In order to make this happen at the necessary speed and without excessive delay (latency), Ars Electronica Futurelab staffers under Ben Ohlsen completely reconfigured the communication between the drones and flight control, and optimized it to the 2.4 GHz module that was being used.

How Do the Drone Get Their Light?

In order to appreciate this, you have to be aware that Ascending adapted the original Hummingbird in several ways especially for this project. Takeoff & landing maneuvers were released to enable the flight control, flight behavior was slightly modified, and, in a technical advance that’s already made it to serial production, there’s an upgraded software library to improve communication between the high-level and low-level CPU, as well as the communication via SPI to the LED modules. Equipping the drones in this way enables them to replicate the light textures of the animations by Michael Mayr. Under the direction of the Ars Electronica Futurelab’s Michael Platz, additional key components were added: first and foremost, the LED module, the diffuser and the landing skids. Thus, the Swarm Hummingbirds differ significantly from their serial-production siblings.

In any case, these Swarm Hummingbirds are currently available for deployment at all sorts of other events!. We hope to be able to present this one-of-a-kind live experience to as many people as possible.

Where do we go from here?

Anyone familiar with the active, ambitious atelier-lab on the banks of Danube is already aware that this is just the beginning of a long-range flight. Where’s it headed? Priority has been given to the potential to tweak the details. And to crank up the numbers—after all, 50 are cool, but nowhere near as cool as 5,000 …

Nevertheless, Hörtner remains silent about which concrete developmental steps are actually getting the go-ahead: “That depends most strongly on the contents we can successfully get across with this. We’ve mastered the technical impediments. The next step is to explore the artistic capabilities and qualities of this new technology.”

The approach exceeds an idle graphical 2D or 3D display in real space. One possible application aims on the augmentation of real space by putting the pixels (spexels) in relation to the environment. By doing so, a planned highway bridge can be drawn into space on location.

How to configure XBee Pro Series 2.

I have two XBee Pro Series2 shipped with “XBP24-B” with ZNet 2.5 protocol.

Previously, XBEE Pro Series1 was set up Zigbee protocol but Series 2 doesn’t.

What makes differences is configuration procedures vary to each module. I want to setup XBee as “Point-to-Point” setting and there are a lot of well-documented tutorials on the Internet which are not quite useful for ZNet 2.5 Protocol.

Fortunately, you could change protocol from ZNet 2.5 to Zigbee using X-CTU, a diagnosis tool that allows you to change mode. Following “XBeeOEM Modules Section” is able to re-configure your XBee modules.

Upgrading fromZNet 2.5 to ZB

Afterward, we are able to apply the following tutorial to our XBee pro series 2.

Please note that whenever you try to configure a XBee using X-CTU, make sure a baudrate is set to 9600bps(Default). If it sets as other else, you might be able to write but it fails at “Putting a XBee into command mode”. In addition, other parameters are forced to be configured at default values so that you need to set up again.

Make sure you saw all writing procedures are properly finished.

Make sure you saw all writing procedures are properly finished.

The following Source from : http://tutorial.cytron.com.my/2012/03/08/xbee-series-2-point-to-point-communication

XBee is very easy and popular wireless device. It is a transceiver, it can transmit data wirelessly and it can also receive data wirelessly. There are several types of XBee module and it might be confusing. The very popular XBee is Series 1 (802.15.4), comes with the firmware to create connection for point to point or star network. But bear in mind, many people actually thought it is using ZigBee protocol, but it is not compliance to ZigBee because it uses the low layer of ZigBee protocol only. Therefore XBee Series 1 (S1) cannot communicate with ZigBee device in the market. Anyway I don think many care because they just want to communicate among XBee, or wanted to have simple wireless communication. The XBee or XBee PRO is basically the same protocol, just PRO module have better transmit power and better receiver sensitivity. So I will be talking about XBee only, not the PRO.

 XBee Series 2 (ZB) does not offer any 802.15.4-only firmware; it is always running ZigBee mesh firmware. It is the new XBee module that we are carrying now. XBee S2 have better performance when you talk about mesh networking where it involve quite a lot of nodes: Coordinators, Routers and End Devices. You can read the datasheet if you want to, but I am going to talk about point to point only :) Bear in mind, XBee S2 CANNOT communicate with XBee S1, it is not compatible in term of wireless communication.

DSCF6313Left is XBee Series 1, Right is XBee Series 2

Point to point two way communication

The major question, can XBee S2 perform point to point communication?

OK, you want to do simple remote control between your control panel, computer or microcontroller to your robot. Besides sending control command to it, you also want to have feedback such as light, temperature, battery voltage, etc. Can I do that with XBee S2? Those that familiar with XBee S1, I am sure you know you will need to configure the Destination Address and Source Address correctly in order to do this right? For XBee S2, it is similar procedure, just you need to make one of the XBee S2 as Coordinator, another as Router.

So get yourself XBee S2, you will need to have two units in order to get communication up. As mentioned earlier, XBee S1 and S2 cannot communicate, so you need to have a pair of XBee S2. Do not mix them up.

Setup

DSCF6309

If you order from Cytron Technologies, the price is similar with XBee S1 (at the time I write this), and it comes with sponge and BB-XBee, the breakout board for XBee. How to use the breakout? Refer to this tutorial. Now, I am not going to use the breakout board because XBee module is 3.3V and you will need to hook up to computer for communication in order to configure it. I will use theSKXBee without module.

  XBee Starter Kit without Module

Plug the XBee S2 module on to SKXBee socket. Mind the polarity. Plug the USB cable to it and computer. You will need to have X-CTU software, I am using version 5.2.7.5, you can get it from here.

DSCF6316DSCF6317

If this is the first time you use SKXBee, you will need to install the driver. Please download the driver from here and refer to themethod to install it.

Assuming you have done installing USB driver and X-CTU, and the USB of SKXBee is plug in properly, you should see the POWER LED on SKXBee ON. There are two XBee S2 modules needed to be setup. I will show the 1st XBee S2 module setup, which I named it Coordinator 1. 2nd XBee S2 module will be Router 1.

Coordinator

You can choose either one of the XBee S2 to configure as coordinator. At the end, the host do not know which is which as XBee will become transparent once it is setup correctly.

Launch X-CTU

X-CTU choose comChoose the COM Port, normally is the largest number. Easily you will see it because it is label as USB Serial Port (COM X). In this example is COM10. Your COM port might be different than mine, just choose those that being label as USB Serial port and click “Test/Query”.

X-CTU testIf the baudrate and COM port number is correct, the X-CTU will display simple information such as modem type, firmware version and serial number. If there is no response, choose the other COM port and ensure the baudrate is 9600 (default).

Coordinator SH edited

Proceed to the right tab on X-CTU, Modem Configuration. Click “Always Update Firmware” and click “Read” to grab data from XBee S2 module.

Choose

ZIGBEE COORDINATOR AT” under Function Set,

Set a preferable PAN ID, I simply set “1234”.

You can also set the Node ID, I set “COORDINATOR1” as node ID, this is not critical.

Record the SH and SL ID on this XBee S2 module, you will need it to set Router module. In my case, the SH is 13A200, SL is408C1470. This is Coordinator Source Address.

Click “Write” and X-CTU will start loading the parameter you just set.

Load Firmware CoordinatorIt will take around 30 seconds to 1 minute to complete the loading.

Coordinator Done program

We will need to configure Coordinator again when you get the SH and SL of router :) . For the time being, we are done for Coordinator. You can close X-CTU now.

Router

If you have another SKXBee, connect it to your computer with another XBee S2 plug in. I will be using the same SKXBee, so I actually exchange the XBee 2S on it.

Launch X-CTU

Choose the COM Port, should be different number than the earlier SKXBee. Your COM port might be different than mine, just choose those that being label as USB Serial port and click “Test/Query”.

Router Test

If the baudrate and COM port number is correct, the X-CTU will display simple information such as modem type, firmware version and serial number. If there is no response, choose the other COM port and ensure the baudrate is 9600 (default).

Proceed to the right tab on X-CTU, Modem Configuration. Click “Always Update Firmware” and click “Read” to grab data from XBee S2 module.

Router Set DH DL edited

Choose

ZIGBEE ROUTER AT” under Function Set,

Set a preferable PAN ID, I simply set “1234”.

You can also set the Node ID, I set “ROUTER1” as node ID. This is not critical.

Record the SH and SL ID on this XBee S2 module, you will need it to set Coordinator module. In my case, the SH is 13A200, SL is4086A429.

Key in the DH and DL address using the SH and SL from Coordinator module. My case is DH: 13A200, DL: 408C1470.

Click “Write” and X-CTU will start loading the parameter you just set.

It will take around 30 seconds to 1 minute to complete the loading.

OK, we are done with Router module. If you like to check, you can go to Terminal tab and key in this command.

Router TerminalTyping “+++” will ask XBee module to enter command mode and will response with “OK”.

ATVR request for firmware version, and XBee will reply, my is 22A7

ATID  request for PAN ID

ATNI request for Node ID, which is ROUTER1 that I just set

ATDL request for Destination Low Address

ATSL request for Source Low Address

ATCN force XBee module to exit command mode. Is fine if you don enter ATCN, after 5 seconds if there is no UART activity, XBee module automatic exit command mode :)

Again, Coordinator

Do not forget, we need to set the DH and DL on Coordinator XBee S2 module. Again, plug in Coordinator XBee S2 module, open X-CTU, read the information, and set the DH and DL that you grab from router’s SH and SL. Click write to load the parameters into XBee module.

Coordinator set DH DL

Done

OK, now both this XBee S2 modules are setup and linked together, once they are powered, they are paired. sending data via UART to one of the XBee module will automatically being transmitted wirelessly to the other XBee module and further transmit out from the UART, and this apply for both way.

Here I have install two SKXBee with Coordinator and Router that we setup. Connected to COM10 and COM25.

 

Xbee SEries 2

If you notice, the DL and SL is paired up. I enter command mode to grab the information we configured and exit the command mode with ATCN. the following text after ATCN and OK is actually happening in transparent mode. The text you type in Router1 XBee will transmit to Coordinator1 XBee and display on terminal and vise versa.

Now, you can use this pair of XBee S2 as wireless point to point communication. It has become same as the XBee S1 if you configure the DL and SL correctly. I hope the tutorial is simple to understand. We have yet to explore the mesh and complicated communication, if you wanted to do that, do come to our technical forum and discuss.

[TedTalk] A refugee from North Korea who is living in U.S.

Often people ask me that “Can you communicate with North Korean?”. I haven’t met North Korean yet in my life but answer is YES.

We are sharing the same ancestors, unfortunately physically being separated since 1953, Korean war.

I found the following TedTalk that was presented by a North Korean who became a refugee in U.S. He is very lucky in that could survive during passing through the border between China and North Korea and have been living in U.S with his foster family.

If you are interested in how do North Korean people being suffered from starving and brutal living condition, have a look the following video. I was touched by this video since can understand a bit of circumstances in North Korea.