khepera, micro robot, faq

Khepera FAQ for Beginners

Compiled by ChanJin Chung | Some are answered by Francesco Mondada

Before you buy a Khepera

What can we do with it?

Obstacle avoidance | Wall following | Target search | NavigationGaze Control | pick and place operations |

manipulating everyday objects | walking

foraging | herding | delivering objectsfolding clothes | cleaning up toxic waste and oil spills

picking up after the children | de-mining |

look after a summer house | imitating a human teacher |overseeing a factory | a space mission | Robot soccer

Khepera contest

1.

How to buy it? Price?

The Khepera robot is sold in a package including a Khepera robot (base plate and processor module),

documentation, interface RS232 to a host computer, power supply, battery charger, cables and software

modules for LabVIEW to command the robot via the RS232. The software LabVIEW, product ofNational Instruments, is not included. This package is sold for 3000.- Swiss Francs. Delivery costs and

local taxes are NOT included in these prices. Shipment costs will be added to the invoice. VAT is

normally paid directly to the customs. Normally the transporter (FedEx, UPS or DHL depending on thecountry) pays the VAT to the customs but then asks you to pay it to them CASH at delivery.... To have

the actual rate of the Swiss Franc you can look on the WEB:

http://www.oanda.com/cgi-bin/ncc orhttp://www.dna.lth.se/cgi-bin/kurt/rates

Concerning a distributor in the US, we do not have one. We had many offers but at the moment and forthis important market we prefer to keep a direct contact with the customers. This allows us a better and

faster support. So feel free to contact us directly... we are used to work with the US. Note that the

prices amd conditions above are for the USA customers. There are some other distributors. (lastmodified 7-1-97)

2.

Could you tell me where you are?

We are in Lausanne, which is in the french part of Switzerland. From Zurich, you go to Bern and youcontinue the same amont of miles and you reach Lausanne. We are 50 km from Geneva.

3.

Service warranty?

Concerning the service warranty, we repair free of charge all failures that can appear during the firstyear and due to normal use. You have just to ship us the robot and we send it back repaired or we

replace it.

4.

Do I pay delivery cost from you to me?

No5.

Could you tell me the method of payment for the robot?6.

Khepera, Micro Robot, FAQ http://www.cs.wayne.edu/~jcc/FAQkhepera.html

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Payment conditions are:30 days from the recipt of the goods (standard invoice)

payment by bank transfert or cheque to K-Team SA

bank transfert to:

K-Team SAChemin de VuassetCP 1111028 Preverenges, SwitzerlandBank: Banque Cantonale Vaudoise, Lausanne, SwitzerlandAccount number: 902.91.32

Can I use my charge card?

credit card no... sorry.7.

Inter-robot communication is possible? Yes, the radio turret can be added to your configuration. This

turret is in production now and will be available in the next months.

8.

Could I also send data from a host computer to a robot or robots?

Yes, we have what we call the "radio base" that can be connected to the computer. The radio base will

be available after the radio turret.

9.

Can I downlod some very basic codes such as for the robot soccer? I am sorry. There is no code for

the robot soccer available yet. However, there are some basic codes are available on the ftp server

ftp://lamiftp.epfl.ch/pub/khepera/softKhep/ or ftp://lamiftp.epfl.ch/pub/khepera/

10.

Mailing list for Khepera?

No...

11.

Khepera won the first prize during the MIROSOT in 1996. Could you tell me about Khepera

configuration at that time? They had a Khepera with a prototype of radio turret and a special turret

with additional sensors.

12.

RAM size? Can I upgrade it?

Our RAM is 256K. No....13.

How many days does it take to ship to me?

We ship by FedEx, so that it will take 2-3 days. These conditions can change depending on the stockwe have, but this kind of delay is more or less standard.

14.

After you buy a Khepera

How to buy the S-line connector for your PC

DB9 female / DB25 male adaptor. Price: $5.99 + tax (Computer City)1.

How can we develop software for Khepera?

There are mainly two way to use the Khepera:(1) By cross-compiling C programs that can be runned on the Khepera processor. By this way you can

write a program like:

do { for( i=0; i<8; i++) { Sensor[i] = sens_get_reflected_value(i); /* Read sensor activation */ }

... your treatement of the sensory informations

for( j=0; j<2; j++) { mot_new_speed_pid(j, Motor[j]); /* Set motor speed */ } } while (TRUE);

This program can be compiled for the Khepera processor, downloaded into Khepera and executed. The

big disadvantage of this approach is that you cannot monitor in a good way what is running on the

2.


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Khepera (no monitor on it....). For people who want to operate in this way we can provide a packagewith the Khepera libraries for the GNU C public domain compiler. Despite the fact that there are some

hacker using it on a PC, we do not support it at the moment on PC platforms, but only on UNIX ones.

Linux is supported. The documentation and the libraries to complete the GNU C public domaincompiler cost 300.- Swiss Francs.

(2) By sending commands to the robot via a RS232 serial line. The robot has a remote control modethat make it possible to send to him commands like:

N

and the robot answers

n,1,12,386,0,12,62,1023,0

where all the numbers are the values coming from the proximity sensors. On your computer you can

process these values following your algorithm and have, as result, the values of speed that you want toapply to the motors. To send the motor command to the robot you can simply send on the RS232 the

command:

D,3,-2

and the robot will apply the speed 3 to the left motor and the negative speed -2 on the right motor. Thenhe will answer:

d

telling that the order has been executed. This second way to control the robot by using RS232 ascii

commands is very powerful because it make possible to control the robot from a program running on

your computer, in a very simple way. The progam running on your computer can be a pure C programthat you have written yourself and that is able to manage the RS232, or can be a MATLAB module that

sends and processes the commands on the RS232, or a LabVIEW module doing the same operations.

All what these program have to do, is send and process strings on the serial RS232 line.Do I have to have a LabView?

From this short overview you can understand that LabVIEW is NOT necessary to run the robot. You

can use easely Khepera from your PC laptop running windows 95. It is sufficient to have aprogramming environment (the one your are used to work with) with a link to the RS232 able to rend

and receive ASCII strings.

The advantage in using LabVIEW is that you can create a visualisation tool in some minutes. The samein a C environment would take much more time and competences. The disadvantage of the LabVIEW

environment is the price (quite expensive but depends on the machine. For informations on this you can

contact National Instruments www.natinst.com) and the fact that this environment is quite slow inexecution. Moreover, LabVIEW is very general, and do not has all mechanisms that you can find on a

specific environment like a robot simulator or your soft.

There is a new aspect. There is now a student edition of LabVIEW which is very low cost so that the"expensive" argument is obsolete....(7-2-97)

3.

How can I install Linux?

Linux FAQ

4.

How can I install cross-compiler on Linux?

First, check your diskette for cross compiler. The version should match with your ROM version.

Because file name in DOS allows max. 8 characters, you probably need to rename files. You candownload UNIX files needed for the cross-compiler from ftp://lamiftp.epfl.ch/pub/khepera/

5.

I cannot load my program. What's wrong with this?6.


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You are supposed to load *.s28 file which is a text file. Try to download by uisng "text file loading".After loading a program to RAM, can I detach, of course, the cable? How?

Yes. You have two choices: you put the robot on batteries (switch on ON), then you download, then

you simply disconnect the robot. Or you can switch ON just after the download and beforedisconnecting, but this can give troubles....

So you do not recommend the second choice?

You can test, but it is possible that you reset the robot switching the power supply from external to

batteries.

7.

Available terminal emulator on a PC using windows 95?

click "start/Programs/Accessories/Hyperterminal/Hypertrm"

connect using: "Direct to Com1"

I dot not specify start bitMark Settings/Ascii setup/Echo

8.

Real Time Mobile Robot Control on the WEB?

The first 24h/24 WEB based mobile robot remote control is available at http://KhepOnTheWeb.epfl.ch.Every user can access and (if the robot is not controlled by another person) control a REAL mobile

robot in a maze, seeing what the robot sees or looking to the maze with an external camera. What you

need is a computer connected to Internet and Netscape. Sorry but Microsoft Explorer do NOT acceptthe video feedback (provided by a Microsoft server...), so you have to use Netscape. This setup has

been built at the LAMI (Microcomputing Lab) of the Swiss Federal Institute of Technology, Lausanne,

Switzerland (EPFL). The robot that you can control is a Khepera equipped with a on board CCDcamera. You can look to the images coming from this camera, OR, if you are lost in the maze, look

from an external pan-tilt-zoom camera, that you can also control from your computer. This set-up is a

demonstrator of what it is possible to do with actual commercial mobile robots and Internet software.All the equipment used in this set-up is commercial. We use a standard Khepera robot equipped with a

K2D video module, a Matrox frame frabber, and external CANON pan-tilt-zoom camera, a PC and

some software including a Microsoft WEB server. This means that you can also build the same set-upin your lab if you want to test this kind of remote control possibilities... Please note that the company

selling the robot offer 10% of discount on the KhepOnTheWeb equipment (Khepera and K2D color

video turret) This demonstrator is part of a swiss research project founded by the Swiss NationalResearch Foundation (project PP-SIC). The goal of our contribution to the project is to provide access

to remote mobile robotics set-ups for benchmarks and research in the field of autonomous robotics.

WARNING: works only using Netscape (Explorer do not support our video feedback)

9.

Disclaimer

Note that this document is provided as is. The information is not warranted to be correct; you use it at your

own risk.

Last modified: July 2, 1997


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khepera, micro robot, faq

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