Der Blog, der Technologie erlebbar macht.

Der Blog, der Technologie erlebbar macht.

Timing is everything

#netacad Team at #worldrun

Interview with Alexander Knauff, network administrator for the timing group.


Q: How do you synchronize the time between all the countries and all the cars?
A: It’s GPS system, we need satellites all over the world, they use UTC. (one common time) It’s the same as every time, every server. The time is synchronized over GPS. There are two GPS mice, fixed on the roof of the cars, two for redundancy.

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Q: How is the car connected to the network?
A: We have laptops with linux, these connect using two 3G sticks (one with Austrian provider and one with local provider) and if both fail, there are satellite modems for fallback. They are Rockblock modems for satellite connections. The Rockblock costs about $ 300. The modem itself is not that expensive, but the data to send is the more expensive part. The data connection is not that fast. The data connection is connected to Amazon cloud servers.

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Q: Why are there trucks with enormous satellite antennas? How can this small box do the same?
A: That is a good question, we can not answer. We are happy to have it. It’s very expensive and we pay per character.

Q: How do you achieve redundancy?
A: We use a custom linux operating system which has been created for only this purpose. It has an easy to use graphical interface.

Q: How is the data transmitted?
A: The data will be stored locally and also sent to the cloud servers periodically. If there is no connection, there are 2 fallback servers in the Global Race Control Centre. Here we have a synchronous connection of 100 mbits.

Q: Why use Amazon cloud?
A: We have been using Amazon cloud for 3 years now. We didn’t have any downtime at all. 4 years ago, there was a downtime though, this was because of a connection mistake. We use Amazon cloud’s load balancer. The Amazon cloud does not have a fixed address, they use dynamic DNS systems.

Q: How long have you been planning this setup or event?
A: We started the planning of it 2 years ago. The planning of the networking and programming has been put to use 1 year ago.

Q: Were there any problems with your connections?
A: Some provider blocked the necessary ports and didn’t want to open the ports. The only solution was to switch to another provider.

Q: What do you use to keep the position of the leading bikers?
A: We use a free app called Backitude. Everybody has the same mobile phone, set up in the same way. It sends the GPS location of the leading bikers every 10 seconds and sends it as an HTTP POST. The next time they get a connection they send their current location. Not only the bikers use this system, the catching cars have it too.

Q: What does every country have?
A: There are 31 countries, every country has three mobile phones, one biker for leading women and one biker for leading men and 2 catch-up cars. If there is a wheelchair race, there is a third catching car.

Q: Does every mobile phone have the same configuration?
A: No, there is always a little difference. There is a part to recognize if the mobile phone is for the biker following the leading man, the biker following the leading woman or a car. This is just for tracking purposes on their system.

Q: How is it possible to recognise the leader?
A: Always after some time we call the different bikers to identify the leader. The biker has a bluetooth headset to send in the information. In some countries, we use walkie talkies to make local communication and then informing the Global Race Control Centre because it is not allowed to use a phone while driving a bike.

Q: Does the catcher car have a camera?
A: No, there is live stream from the media teams only. The catcher car equipment is solely used for timing. So many TV cars will be there. The media will be on the catcher car lane

Q: What is a BIB number?
A: The BIB number is the starting number to identify a runner. We use RFID tags in order to keep track of the identity of runners.

An Interview with John Kelsey, the COO of Chronotrack, the company behind the RFID technology.


Q: How does the car communicate with the Global Racing Control Centre?
A: They use a laptop with a customized linux operating system. It is called OBU (On-board Unit)  internally. They have an easy to use graphical interface. They have a second battery. As backup there is also an AC/DC converter to charge the OBU. The OBUs send small data packages over the network. It contains OBU-id, BIB-id (runners wordwide unique number), GPS-time (UTC timestamp) and GPS coordinates, its about 40 characters. Every time a runner is caught by the catcher car, a package is created and if there is a connection, then all the data is sent.


Q: How do you make sure the driver knows the OBU is okay while driving?
A: The OBU beeps every 3 minutes to say, hey I’m here. This can not be muted.

Q: How many OBUs do you have per car?
A: One OBU per car.

Q: Why is it not possible to cheat?
A: There are regular checks on the track.

Q: Was it difficult to find appropriate running tracks?
A: Yes, we try to have only 1 direction and no loops within the running track, but sometimes this was not possible, because of highways. There was also a problem with streets smaller than 4 meters. In India the streets are sometimes 8-20 meters, this is too big, because the sensor can only detect perfectly up to 6 meters. The car needs 2 meters space. Ideally the runners have 6 meters of space.

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These RFID scanning boxes have a modem and GPS integrated but they are heavy and do not have battery power. There aresmall ones that have about 10 hours and the big ones have 8 hours.Every car has an AC/DC for charging.

Q: When do you start preparing the cars, the day of the run?
A: They have to start 2 hours before the race for the registration of satellites and etc.. They have to work through a checklist in order to get everything OK.

Q: How many people are in a catcher car?
A: In every car there is a driver, the timer with the laptop and a third person with telephone.

Q: How is the functionality of the cars checked?
A: The country operators of the Global Race Control Center can see if everything of the cars is all right, with green status lights.

Q: Like a dashboard?
A: Yes, we have interfaces for every OBU connected. So we can see which OBUs are online and if we have any problems we are alerted with a red light on a dashboard.

Q: Is there always a network connection?
A: No, sometimes we know the cars have no connections to the network, because they know that in some parts there is no GPS connection, but as soon as they have a connections again, it is okay because they don’t need data every minute. They save the data locally too.

Q: Was there any problem with privacy?
A: No, because there is nothing private collected. If you see the BIB number as something private, then yes, but the athletes agree to this with registration.

Q: How big is your team in the Global Racing Control Centre?
A: The main team has about 10 people, including me. About 30 people from datacapo. But timers all around the world work for us, because it’s impossible to send so many people all around the world.

Q: Are there a lot of students working on this project too?
A: Yes, a lot of students were hired.

Chronotrack MiniTrack (RFID Sensor for cars) User Manual:

Rockblock Rugged Sattellite transmitter:


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