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speed accuracy ?

tony 3 years ago updated by risi@me com 2 years ago 3

I recently received a speeding ticket and the policeman said he clocked me at 120km/hr.   I was sure that I wasnt going that fast and when i checked my drive-log on teslafi i seems to indicate that I was traveling at no more than 108km/hr.  I would like to use this teslafi data in court ..  has anyone used it like this? how accurate is teslafi speed record? how is the sped data obtained ? (does it use gps location devided by time or is "speed" supplied as data from the car).  thanks for your help?

I had a same problem, the judge is usually is colluding with Police and you need to wiew the problem in a multiple different view.

First of all you need an IT Engeneer to prepare an explanation about how to Tesla send the data over LTE to the Tesla’s server in order to visualize this info to the Tesla Application.

Then you need to explain to the judge the Token system to clarify the data collected and presented it’s related o. your car, The access token it’s a common method to Autenticate and Authoraze you to view the data from your car and not other car and this a common method used normally around world to do this.

Now you need to explain to the Judge where is the method Teslafi use to read this data from the Tesla’s servers, this method is a Json API, the documentation is not released from Tesla but is public in a douzen of website like www.teslaapi.io.

Finally you need to explain to judge Teslafi collect the data into a read only database readed only with a web access, so the collected data is not manipulate from an external hacker.

Finally the car send data every 20 second to the Tesla’s server and this is the interval you have the lecture, so you have the speed lecture every 20 second.

To be sure the Judge don’t have any escape way, you need to see in the ticket the hour of the radar lecture, and you need to collect in Teslafi une or two lecture before and one or two after, then you nee do calculate the medium speed between this lecture,  you have the lecture of the odometer and the hour minute and second of the lecture, with the formula calculate the medium speed between the point.

This because in my case the Judge he said i accellerate in the middle of the speed lecture ( in the 20 second between the lecture), and for this reason the Policeman have right, but i know before and in the document you need to proof your speed is linear so no big accelleration be in the middle of the tesla lecture, the medium speed mist be equal or less the point you take a fine.

The Judge in this case don’t have reason to confirm the ticket and cancel them, because now the car it’s a real compurer and collect the data like a aircraft black box.

Another important tip… in israel you are not forced to present all the trip data, but you must show only the lecture related to the hour the police read your speed.

In Israel is important to force the Policeman to write in the ticket note something, you must advice the police you have the speed data and you want show him, if he refuse that you must be sure this is write in the note, because if not maybe the judge cancel the fine but don’t give you the Lower remboursment, otherwhise if the policeman refuse to read the speed data collect from car, you don’t have any choose and you must pay a Lawer to present this issue in front of the court, the Policeman is a public officer and the judge mus be pay your expenses.

The document you prepare with this information it’s usefull every time tou have an unreasonable ticket, so you must redact only one and maybe you change the data if needed.




thank you for the information it is a great help to understand that the data is Stored in a read-only format and cannot be manipulated.

I am still not clear on how the speed data is calculated.

I would really like to know if it is calculated using the GPS location or is it taken from the wheel speed

I have written to the police and I have shared with them a link given to me on teslafi for the trip data which shows I was travelling at a lower speed than they say

l hope that the police will consider this and decide to cancel the ticket otherwise I will have to go to court and I guess that will be expensive

thanks again

The Speed is take from the car's speedometer, I hope based on my test, but Teslafi must answer your question here.