Help with data acquisition please
11-29-2007, 01:15 PM
#46
Nordschleife Master
As I remember you had a post up a while back when you built you car about sensor placement, no?
You can pick up tach signals and TPS off of the DME so no additional sensors needed for those.
11-29-2007, 03:11 PM
#47
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That would make for a nice tutorial. I'm going to be asking about tach, throttle, brake, and steering sensors for the Pista (should I go that route) in my SC the upcoming months also.. And how does the system know what gear you are in in a car without OBD? Or is that even possible?
The older 911's do not have a TPS sensor, but do have an idle switch and a WOT switch. You could actually use these sensors to gather some useful information, as it will let you know when you are off the gas, part throttle, or WOT. Obviously a real TPS would be ideal as it gives you more valuable data, only takes up one input, and is only one piece of data to look at.
I got the idea from Jack Olsen on Pelican to use a Linear Throttle position sensor from Race-Technology for $58.
Getting the TPS positioned just right so that at exactly 0% when at idle and 100% when at WOT took some time and effort but was worth it.
Data logger's can figure out gear by speed and RPM. I think you just need to enter in the gear ratio's into the software.
-Scott
Last edited by sbarton; 12-05-2007 at 10:48 PM.
11-29-2007, 03:18 PM
#48
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I got the idea from Jack Olsen on Pelican to use a Linear Throttle position sensor from Race-Technology for $58.
Getting the TPS positioned just right so that at exactly 0% when at idle and 100% when at WOT took some time and effort but was worth it.
-Scott
Getting the TPS positioned just right so that at exactly 0% when at idle and 100% when at WOT took some time and effort but was worth it.
-Scott
11-29-2007, 03:54 PM
#50
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G2X dash is much superior (IMHO) to the traqmate in terms of readability, available functions, and size to Traqmate and is (I think) about $100 cheaper for the basic setup which includes the dash. Software, at least in previous versions, is not that user friendly but not horrendous either once you get used to it.
Adding additional sensors to the G2X is also marginally more expensive as you have to buy their proprietary cabling - however you will not need to use their sensors - any brand sensor can be used as long as you get the G2X cable (common misconception) You can pick up tach signals and TPS off of the DME so no additional sensors needed for those.
Traqmate is marginally more expensive, has better software, but the dash is smaller and has fewer functions. Easier to add additional sensors
I went with the G2X as I wanted the more readable dash as my primary concern other than the basic 2 axis data acq. and GPS.
Adding additional sensors to the G2X is also marginally more expensive as you have to buy their proprietary cabling - however you will not need to use their sensors - any brand sensor can be used as long as you get the G2X cable (common misconception) You can pick up tach signals and TPS off of the DME so no additional sensors needed for those.
Traqmate is marginally more expensive, has better software, but the dash is smaller and has fewer functions. Easier to add additional sensors
I went with the G2X as I wanted the more readable dash as my primary concern other than the basic 2 axis data acq. and GPS.
The cost of the TraqMate is marginally more expensive, but the cost of adding inputs to the G2X is significantly more expensive due to the proprietary vNet cables. Each input requires it's own vNet cable at a cost of $120ea. That's almost $500 extra if you want to log 4 additional sensors (not including the cost of the sensors).
My GPS Data Logger overview post on Trackpedia covers a lot of this in more detail.
They are both great products. Your needs and intended use, along with overall budget will probably dictate which one you go with.
-Scott
11-29-2007, 03:56 PM
#51
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One thing I noticed is that you need to cut the wires as short as possible in order to have the widest possible range of readings (ie I was only reading 0-2v when I tested the sensor with 1meter of wire, but once I significantly shortened the wire it would read 0-4.6v).
I also added a brake indicator to log. Basically I just tapped into my brake light switch and ran a wire to the TraqData and plugged it into one of the Digital Inputs.
-Scott
11-29-2007, 03:59 PM
#53
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As I remember you had a post up a while back when you built you car about sensor placement, no?
You can pick up tach signals and TPS off of the DME so no additional sensors needed for those.
The other options are to tap into the 12V ECU signal, 12V Fuel injector pulse, or 12V Coil-on-plug firing signal.
-Scott
11-30-2007, 01:29 PM
#54
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Sbarton,
I am very much tempted by the Traqmate system as it seems to be the simpliest one. But I need brake,steering angle and accelerator feedback.
I am scared by the possible complexity of connecting the sensors and , as I am not in an english speaking country, I am not sure that the local mechanics will like to fight with a - new to them - system. Here they only use AIM or MOTEC, which are out of my price range..
Sorry to keep you busy... Do you have a brake pressure indicator ? Can a steering angle position sensor be easily connected to the tracqmate ?
Was it difficult to find the sensors and connect them to the main unit? How was it done ? Did you do it your self ? Do you need technical knowledge?..
Thank you in advance for your help...
HTML Code:
I have a throttle position sensor and brake indicator.
I am scared by the possible complexity of connecting the sensors and , as I am not in an english speaking country, I am not sure that the local mechanics will like to fight with a - new to them - system. Here they only use AIM or MOTEC, which are out of my price range..
Sorry to keep you busy... Do you have a brake pressure indicator ? Can a steering angle position sensor be easily connected to the tracqmate ?
Was it difficult to find the sensors and connect them to the main unit? How was it done ? Did you do it your self ? Do you need technical knowledge?..
Thank you in advance for your help...
11-30-2007, 01:59 PM
#55
Nordschleife Master
Brake pressure sensors are easy to install and only require engineering new lines. A steering angle sensor can be installed to either the rack itself, or to the steering column. Only minor fabrication should be required. I posted some pictures of my installs on the 964 forum. Do a search on "racecar project"
11-30-2007, 02:03 PM
#56
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Sbarton,
I am very much tempted by the Traqmate system as it seems to be the simpliest one. But I need brake,steering angle and accelerator feedback.
I am scared by the possible complexity of connecting the sensors and , as I am not in an english speaking country, I am not sure that the local mechanics will like to fight with a - new to them - system. Here they only use AIM or MOTEC, which are out of my price range..
Sorry to keep you busy... Do you have a brake pressure indicator ? Can a steering angle position sensor be easily connected to the tracqmate ?
Was it difficult to find the sensors and connect them to the main unit? How was it done ? Did you do it your self ? Do you need technical knowledge?..
Thank you in advance for your help...
HTML Code:
I have a throttle position sensor and brake indicator.
I am scared by the possible complexity of connecting the sensors and , as I am not in an english speaking country, I am not sure that the local mechanics will like to fight with a - new to them - system. Here they only use AIM or MOTEC, which are out of my price range..
Sorry to keep you busy... Do you have a brake pressure indicator ? Can a steering angle position sensor be easily connected to the tracqmate ?
Was it difficult to find the sensors and connect them to the main unit? How was it done ? Did you do it your self ? Do you need technical knowledge?..
Thank you in advance for your help...
The difficulty really lies in installing the sensors into your vehicle. Once that is done, all you need to do is run the wire from the sensor to the Logger. The Logger just reads the voltage (0-5V) and records it. The software then translates the voltage to either Throttle position (0-100%), steering angle (-200* to 200*), etc.
If you want steering angle, brake pressure, and Thorttle position, the G2X has an all in one sysytem (620-KT-STBB) for that. It is VERY expensive however ($1400). Actually all steering angle sensors and brake pressure sensors will be expensive though.
-Scott
12-03-2007, 02:04 PM
#58
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Originally Posted by lowside67
Hey,
I see you bought the TraqMate video package.
How much was it? The only video and data package I see is $1699 now...
-Mark
I see you bought the TraqMate video package.
How much was it? The only video and data package I see is $1699 now...
-Mark
TraqMate no longer offers the Traqmate Basic Video bundle. That was basically the TraqMate Basic with the TrackVision software. I suspect this is to reduce confusion with their other Video options that they have added since I purchased my Traqmate.
Now you would have to purchase the TraqMate system and add on the TrackVision software from the menu.
-Scott
12-03-2007, 02:37 PM
#59
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I am next to buying a Traqmate. I am intrigued by the 1-3 meters accuracy consequences..
Does this mean that,
1)braking at the same exact place:
In lap one my Data acquisition System (DAS) could show a braking point that can be 1 to 3 meters away from the braking point shown in lap two ? and/or,
2) Turning at the same exact pointIn lap one my Data acquisition System (DAS) could show a turning point that can be 1 to 3 meters away from the turning point shown in lap two ?
I have read in the Traqmate manual ( page 26) that the sampling rate can be set in 10, 20 or 40 Hz mode. (They recommend 20 hz.) Why wouldn't recommend - 40 hz. Is there any tradeoff involved when setting this 40 hz sampling rate ? Would this 40Hz sampling mode increase the accuracy ?
Does this mean that,
1)braking at the same exact place:
In lap one my Data acquisition System (DAS) could show a braking point that can be 1 to 3 meters away from the braking point shown in lap two ? and/or,
2) Turning at the same exact pointIn lap one my Data acquisition System (DAS) could show a turning point that can be 1 to 3 meters away from the turning point shown in lap two ?
I have read in the Traqmate manual ( page 26) that the sampling rate can be set in 10, 20 or 40 Hz mode. (They recommend 20 hz.) Why wouldn't recommend - 40 hz. Is there any tradeoff involved when setting this 40 hz sampling rate ? Would this 40Hz sampling mode increase the accuracy ?
12-03-2007, 02:41 PM
#60
Nordschleife Master
There is the sampling rate and then there is the GPS update frequency and you need to look at both. If you have a system that updates GPS at 10hz, sampling at 20 or 40hz gaines you no benefit.