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I'd say they're not likely to offer an upgrade. 1) they'd rather just increase the incentive for you to buy a newer model and/or 2) why tie up the service centers when they are already at capacity with the model 3 on the horizon.
I'd say it's more 1 than 2.
PowerTools for iOS seems to be the favorite here until you are ready to take you car apart and try TM-Spy.
The speedometer is pretty accurate. You're around 4.2 seconds right?
It would be especially fun to see your TM-Spy data next to @rsan's data. New drive unit and battery against old drive unit and battery. My guess is the performance results would be pretty close - but that some of the other internal results could be very different.
Come on then................WHAT TIME IS TOO GOOD TO BE TRUE
I used a gopro and set it to 240 fps. Then held a stop watch next to the steering wheel to make sure the videospeed matches real time.
I then imported the videoclip into adobe premiere. Trimming the video frame by frame. For 0-100 km/h.
I got 4.13 seconds in the first run and 4.12 sec. in the second run.
I have a Model S 75D with the 85kwh battery. Vin 1955XX I have not done any "uncorking"
The next step might be to validate the accuracy of the frame rate. I suggest counting the frames in 100 seconds. A frame rate differing from exactly 240/sec will directly affect results. There will be a buffer in the GoPro affecting storage of frames. The frame rate might be different depending on whether the buffer us full or not. Ideally you'd like the buffer to be in the same state throughout the run. Recording at the minimal resolution allowed may keep the buffer from filling.
How did you establish the first frame in the 0-60 sequence? If you chose the first frame exhibiting a "1" instead of a "0", you might have underestimated the time just a bit. I suggest taking the number of frames elapsing between a displayed 1 and 2 then subtracting that number from the first frame with a 1 to set the start time. It won't be perfect but it should get you closer. There may be a processing lag time for the computer to take the data from the sensors then display it on the screen. If we assume the lag time is uniform, then it will affect the display on both ends of the run so shouldn't affect results.
If the refresh rate on the car display is slower than the camera frame rate, then the faster camera frame rate won't add to accuracy. I might suggest a frame rate of 120 if available. That may have implications as far as the camera buffer goes and it should allow more head room in the data recording so may make the frame to frame timing more accurate, that is if the 240 rate fully consumes the camera's resources.
At the end of the run, the displayed speed digits would be changing pretty quickly. Was there any difficulty establishing the frame at which the car hit 60 MPH (or 100km/h)?
If it turns out the frame rate is accurate and consistent, you may have given us a way to accurately time our cars. Thanks.
David
Wow, You seem to have a good understanding in these things.
1. I used a stopwatch and compared the numbers of that to the timing in premiere. 1 second matched to 1 second in the timeline. Do you think thats a good method?
2. As you said, there is a small timeframe before absolute zero, and when rhmmtge speedometer turns to "1", I didnt count any frames backwards, but i tried to see when the first movement in surroundings was. I set the frame just before to be my "in point".
And when the display had turned comletly to 100, I set my "out". (There were a few frames with 99 transforming to 100).
I didnt reallt follow you why i should try 120 instead of 240..
The reason is that a frame rate of 240 is "oversampling". It doesn't matter if the camera is just as accurate at 240 as it is at 120 so there would be no accuracy penalty. But if the 240 frame rate is taking the camera to the absolute limit, then it may function more accurately at a rate of 120. If the car screen updates at 80 frames per second (arbitrary number pulled out of my hat) and you photograph at 240 frames per sec, then the camera will capture 3 frames between every screen refresh. You could capture at 1000 frames per second and there will be no increase in accuracy. Think of granules. The granular size for the display is 1/80 second in this example. It cannot change the image displayed more frequently than the refresh rate. In the interval, the screen won't change no matter how many times you photograph it. So if you can trade that excessive number of frames for something else, then you may benefit.
It may be that the screen shows a blurred combo image in the middle of its refresh cycle and it might be that only one of the 3 images is clear. At a rate of 120, it is still capturing more images than the screen can change, so if one frame hits on the transition, then the next camera frame should get a clear image. There is no frame that shouldn't be clear in one of the 2 successive frames. If one is blurred in transition, then the next 1/120 second should be clear. (If the refresh rate is 120 for the car, then it would be possible to get a series of frames in which each hits the transition. There is no need for Tesla to have a screen refresh rate that high, though.)
So the screen refresh rate represents the fastest the car can display another number. Photographing the screen at a much faster rate just isn't more accurate. If the camera loafs at 120 and gets a frame every 1/120 seconds and if the camera struggles a bit at 240, then it seems the frame timing might be more consistent at the slowe frame rate. You might trade that uselessly high rate for something else, perhaps you need better resolution.
As far as the stopwatch goes, I'd use a digital timer/stopwatch. The term "stopwatch" brings to mind a mechanical device.
Start times... you could use a switched LED. Mount the switch on the accelerator, have the LED in the camera's field, then the foot depressing the accelerator could light the LED to give you the start frame.
You could rig a laser pointer outside the car pointed to a mirror inside the car. When the laser is lost in he image, the car is moving.
Fun, eh?
Best,
David
If you capture the power meter in the IC as well couldn't you use that for the start time? (I don't know how quickly it updates, but you could see how many frames it moves before the speed changes from 0 to 1.)
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