Low Cost Complete Data Acquisition System
#16
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The steering input is IMO the single most valuable data source for rating the driver, as it's the primary way the driver interacts with the car (especially true for less experienced drivers). I'd say it's the #1 item on the list for tuning the driver, not the car. Unfortunately it's also much more difficult and expensive to set up that instrumentation than other inputs, so naturally it's much less common.
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924racr wrote"The steering input is IMO the single most valuable data source for rating the driver, as it's the primary way the driver interacts with the car (especially true for less experienced drivers). I'd say it's the #1 item on the list for tuning the driver, not the car."
Vaughan,
I'm really new to DAS just starting to read about it. O.K. lets assume that is true. How can anyone with a brand new AIM ever hope to use this new data? If I go out to a track and find my steering input angle to be "x" in turn 5 what does that mean? I would think you need to have data from a pro to also compare what you do. You could use GPS to fix your turn-in to the pro's turn in etc but don't GPS unit still have an error of 3 or 30meters? Is the GPS in the AIM type units have enough resolution?
Vaughan,
I'm really new to DAS just starting to read about it. O.K. lets assume that is true. How can anyone with a brand new AIM ever hope to use this new data? If I go out to a track and find my steering input angle to be "x" in turn 5 what does that mean? I would think you need to have data from a pro to also compare what you do. You could use GPS to fix your turn-in to the pro's turn in etc but don't GPS unit still have an error of 3 or 30meters? Is the GPS in the AIM type units have enough resolution?
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I agree with Billybob. How can you make use of the steering data? What exactly does it tell you?
I can see the possible use in comparing the car under one set-up to the same car with the same driver under another set-up -- i.e. for diagnosing the car -- but how can you use this to examine the driver (other than basic stuff like he isn't being smooth -- the sort of thing that is obvious to just about anyone watching from the passenger seat).
In playing with the DL1 I do find that the GPS is very accurate. I have some doubts about how they combine the GPS and accelerometer data though. I get the feeling that if they were doing a better job of using all of this data then it could become highly accurate (inches).
Stephen
I can see the possible use in comparing the car under one set-up to the same car with the same driver under another set-up -- i.e. for diagnosing the car -- but how can you use this to examine the driver (other than basic stuff like he isn't being smooth -- the sort of thing that is obvious to just about anyone watching from the passenger seat).
In playing with the DL1 I do find that the GPS is very accurate. I have some doubts about how they combine the GPS and accelerometer data though. I get the feeling that if they were doing a better job of using all of this data then it could become highly accurate (inches).
Stephen
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Originally Posted by FixedWing
I wonder how useful this data really is?
From my perspective, there are two seperate uses for the data. The first is in analysing the driver and the decisions he makes. The second is to analyse the car and how well the car is tuned for conditions.
I believe that much of the data people are talking about seems to relate to tuning the car and not to the driver. I think that is true for the steering angle.
I think that there is a real risk in being burried in data. From the driver's perspective, only a very little information related to the decisions he is making are needed.
Whether the driver is setting the car up correctly for a corner is probably something best judged by the seat of the pants. This should be obvious. And I think it can be judged much better this way than through an analysis of data after the fact.
Stephen
From my perspective, there are two seperate uses for the data. The first is in analysing the driver and the decisions he makes. The second is to analyse the car and how well the car is tuned for conditions.
I believe that much of the data people are talking about seems to relate to tuning the car and not to the driver. I think that is true for the steering angle.
I think that there is a real risk in being burried in data. From the driver's perspective, only a very little information related to the decisions he is making are needed.
Whether the driver is setting the car up correctly for a corner is probably something best judged by the seat of the pants. This should be obvious. And I think it can be judged much better this way than through an analysis of data after the fact.
Stephen
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What Rjay said made sence. Is there a DAS that shows Lat G's on a screen you can see while driving like a tachometer? It seems to me all the systems log and then you analyze post race.
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Originally Posted by fatbillybob
Is there a website that is kinda like a DAS primer? I have one book on the subject on order and the only one I could find.
The Aim stuff (Race Studio) can be downloaded from http://www.aim-sportline.com
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RJay's pretty much covered it. Yes, you can get the same info from a video, but DAS allows much more detailed and precise evaluation of steering input. Furthermore, when you feed steering angle into some of the higher-order calculations (think Ackerman steering bicycle model of yaw rate - may want to consult Gillespie's vehicle dynamics book on this, I don't have my copy handy) you can get an even more detailed analysis.
Most simply put, you can generate a driver's request yaw rate based on the Ackerman model for steering (steering and vehicle speed as inputs) and compare this with recorded yaw rate (from the sensor). If these are smooth and close, you're probably doing a good job of driving the car at the limit. If you're not consistently holding the car there, due to lack of smoothness or over/undershoot, you'll be able to draw some conclusions about your driving technique.
Sorry if this sounds a little vague, but I don't have any data I can post to discuss this with - as mentioned, I still don't have a steering angle sensor on my car either.
Most simply put, you can generate a driver's request yaw rate based on the Ackerman model for steering (steering and vehicle speed as inputs) and compare this with recorded yaw rate (from the sensor). If these are smooth and close, you're probably doing a good job of driving the car at the limit. If you're not consistently holding the car there, due to lack of smoothness or over/undershoot, you'll be able to draw some conclusions about your driving technique.
Sorry if this sounds a little vague, but I don't have any data I can post to discuss this with - as mentioned, I still don't have a steering angle sensor on my car either.
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If anyone would like detailed info or would like to purchase a system, please contact me and i can hook you up not only with a good price from a very reputable distributor (aimsports recomended) but also a year of support for free! As well as other things that most other companies don't do,like test all the sensors/systems before they ship out, custom make harness's, offer Sensor data anlysis if you feel something is wrong, etc etc etc.
For $2500 you can get a fully loaded top of the line Aimsports MXL Pro system with some sensors!
For $2500 you can get a fully loaded top of the line Aimsports MXL Pro system with some sensors!
Last edited by 95m3racer; 10-11-2011 at 09:20 PM.
#25
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For all the other DA novices like me, let me add my $0.02.
I don't consider AIM to be a low-cost solution for a novice/intermediate. Something like $1500 - $2000 for the system plus $500 - $1000 for installation depending where you go. Compare this to the Race Technology DL-1, which sells for $900 with no installation costs. Now THIS is a low-cost solution, but it does have its limitations. First, you don't have any/many sensors with the basic install, but heck you're a novice/intermediate and you'll already be overwhelmed with the basic info that GPS/accels give you. Second, you don't have cockpit display with real-time info, but heck you're not trying to win an endurance race. As far as the GPS accuracy, I've found it to be accurate enough to differentiate different lines I've taken. It's gotta be at least as accurate as using accelerometers and wheel speed sensors to draw the track map (i.e. AIM), or so I'd think.
I've also found the DL1 software a bit difficult to learn, although they released a new version a few months ago that is much improved. I've been simply walking through the help file to learn how to use it, and this seems to suffice. I've checked out the book "Competition car data logging" by McBeath but I've found it useless. Total waste of money. Even if you don't want to buy a DL1 you can download their software and work thru the help file with sample data to learn the basics. One thing I just learned is how to look at the spped traces of a few laps along with the "time slip" curves, which tell me exactly where I'm losing time (compared to the theoretical best lap) or where I'm consistent from 1st to last lap, etc.
Anyway, I'm not affiliated yada yada yada just a satisfied customer.
I don't consider AIM to be a low-cost solution for a novice/intermediate. Something like $1500 - $2000 for the system plus $500 - $1000 for installation depending where you go. Compare this to the Race Technology DL-1, which sells for $900 with no installation costs. Now THIS is a low-cost solution, but it does have its limitations. First, you don't have any/many sensors with the basic install, but heck you're a novice/intermediate and you'll already be overwhelmed with the basic info that GPS/accels give you. Second, you don't have cockpit display with real-time info, but heck you're not trying to win an endurance race. As far as the GPS accuracy, I've found it to be accurate enough to differentiate different lines I've taken. It's gotta be at least as accurate as using accelerometers and wheel speed sensors to draw the track map (i.e. AIM), or so I'd think.
I've also found the DL1 software a bit difficult to learn, although they released a new version a few months ago that is much improved. I've been simply walking through the help file to learn how to use it, and this seems to suffice. I've checked out the book "Competition car data logging" by McBeath but I've found it useless. Total waste of money. Even if you don't want to buy a DL1 you can download their software and work thru the help file with sample data to learn the basics. One thing I just learned is how to look at the spped traces of a few laps along with the "time slip" curves, which tell me exactly where I'm losing time (compared to the theoretical best lap) or where I'm consistent from 1st to last lap, etc.
Anyway, I'm not affiliated yada yada yada just a satisfied customer.
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Shp:
I agree, the DL1 looks pretty nice but the software issue is critical. If you can't get at the data and perform the analysis, collecting the data is worthless. I don't know if the software is good or bad, just that it better be pretty good (the aim is) if you want to use the system. I think the DL1 GPS is likely much more accurate than the Aim accel (now - aim is coming out with GPS also). The data logging book is terrible. The Dash Display is nice because you can look at and alarm different parameters.
Finally though, and my biggest problem with the DL1 is if you want all the data, like you should get with the Aim and CAN link, You would need a new system of would need to get your own drivers written.
I agree, the DL1 looks pretty nice but the software issue is critical. If you can't get at the data and perform the analysis, collecting the data is worthless. I don't know if the software is good or bad, just that it better be pretty good (the aim is) if you want to use the system. I think the DL1 GPS is likely much more accurate than the Aim accel (now - aim is coming out with GPS also). The data logging book is terrible. The Dash Display is nice because you can look at and alarm different parameters.
Finally though, and my biggest problem with the DL1 is if you want all the data, like you should get with the Aim and CAN link, You would need a new system of would need to get your own drivers written.
#27
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Originally Posted by ColorChange
I agree, the DL1 looks pretty nice but the software issue is critical. If you can't get at the data and perform the analysis, collecting the data is worthless...
Originally Posted by ColorChange
The Dash Display is nice because you can look at and alarm different parameters.
Originally Posted by ColorChange
Finally though, and my biggest problem with the DL1 is if you want all the data, like you should get with the Aim and CAN link, You would need a new system of would need to get your own drivers written.
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Our exchange sounds a lot like the discussion between my buddy and I last winter when we were trying to decide which system to buy. He said "AIM because it's technically better and has a helpful display" and I said "DL1 because it's a great value and gives us novices sufficient information." We were both right, I suppose, but in the end, it totally depends on what you want to get out of the system.
#28
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Originally Posted by Shpeyeda
The previous versions of RT's software were pretty weak, but the current is good.
In my opinion, Race-Tech would do well to concentrate on getting this most important part of their product into better shape rather than working on trying to expand it.
Stephen
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Originally Posted by Shpeyeda
For all the other DA novices like me, let me add my $0.02.
I don't consider AIM to be a low-cost solution for a novice/intermediate. Something like $1500 - $2000 for the system plus $500 - $1000 for installation depending where you go. Compare this to the Race Technology DL-1, which sells for $900 with no installation costs....
I don't consider AIM to be a low-cost solution for a novice/intermediate. Something like $1500 - $2000 for the system plus $500 - $1000 for installation depending where you go. Compare this to the Race Technology DL-1, which sells for $900 with no installation costs....
Originally Posted by Shpeyeda
I've also found the DL1 software a bit difficult to learn, although they released a new version a few months ago that is much improved. I've been simply walking through the help file to learn how to use it, and this seems to suffice. I've checked out the book "Competition car data logging" by McBeath but I've found it useless. Total waste of money. Even if you don't want to buy a DL1 you can download their software and work thru the help file with sample data to learn the basics. One thing I just learned is how to look at the spped traces of a few laps along with the "time slip" curves, which tell me exactly where I'm losing time (compared to the theoretical best lap) or where I'm consistent from 1st to last lap, etc.
Anyway, I'm not affiliated yada yada yada just a satisfied customer.
Anyway, I'm not affiliated yada yada yada just a satisfied customer.
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Hell, AIM MyChron3's start at closer to $500! You also get the same pro-quality analysis software as for the $2000 unit, if I'm not mistaken. My AIM MyChron3 Gold XG was around $500 IIRC. I'd love to be able to use one of those AIM systems with CAN capability - but the poor thing would have no other computers to talk to in my racecar! It's the only bit of silicon in my racecar outside of the electronic ignition!!! CC et al are talking about a much higher level of DAS than what is needed for starters.