University of Maine FSAE Engine Team
Data Acquisition System
Team Members:
Stephan Becker
Peter Farnum
Jacob Morissette
Dwight Whitney
Purpose:
To propose a solution for a system to gather, display, and store crucial data from the University
of Maine FSAE vehicle.
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Contents
Summary: ...................................................................................................................................................... 1
Background: .................................................................................................................................................. 2
Problem Definition: ....................................................................................................................................... 2
Concepts: ...................................................................................................................................................... 2
Options:..................................................................................................................................................... 2
Race Technology DL-1 with Dash2 Option: ........................................................................................... 2
Ground-Up Arduino: ............................................................................................................................. 3
Economic Analysis: ........................................................................................................................................ 6
Final Decision: ............................................................................................................................................... 6
References: ................................................................................................................................................... 7
Appendix A: ................................................................................................................................................... 8
Data Logger Grade Sheet: ......................................................................................................................... 8
1
Summary:
A real-time, data acquisition system which is able to display its data to a programmable “dash”
type LCD screen will provide a way for the FSAE vehicle team to view vehicle performance
during both racing, and testing events. This will increase the vehicle performance and increase
the value of the vehicle at competition. Through research and team feedback, we have
determined the most reasonable methods for creating a data acquisition system in terms of both
hardware and software. The research was based on a set of criteria which can be seen in Table 2
of Appendix A.
The three options to be analyzed include the Race Technology DL-1 data-logger with the Dash2
optional display screen, a ground- up Arduino model, and the Performance Trends DataMite II.
Each system has their pros and cons, but each will meet the needs of the FSAE team.
The DL-1 and Dash2 is an option that is purchased as a package, and is ready out of the box.
This combo features an adequate data logging system with built in accelerometers and GPS
units, as well as a fully programmable dash unit capable of displaying real time data from the
vehicle, in order for it to be seen by the driver. With included software to analyze the logged
data, the DL-1 is a viable choice.
The ground-up Arduino system will require a great deal of assembly, and programming to meet
the needs of the FSAE team. This system is beneficial due to the fact that it will allow us to
completely design the data-logger to the exact needs of the team, but all expansion capabilities
are sold separately. One thing the Arduino does have over the others however, is its price. At
about 1/3 the cost of both the DL-1 (with no screen), and the DataMite, the Arduino cannot be
overlooked.
The DataMite has many similar features as the DL-1, but lacks essentials such as GPS, and a live
data display option. Like the DL-1 however, it is ready out of the box, and features built in
accelerometers. However, at about the same price as the DL-1 (assuming the DL-1 was
purchased without the display screen), it does not seem to be a viable option since it lacks some
of the basic desired features.
The software options in consideration for each unit are the programs included with both the DL1 and the DataMite, and a self programmed package for the Arduino logger. Due to team
knowledge, the pre programmed software packages that the DL-1 and the DataMite offer are a
more appealing option. Though the thought of completely building the Arduino from the ground
up, and then building a computer program to analyze its data would be satisfying, we feel it is
more beneficial to focus our design work elsewhere. Due to competition constraints, the engine
intake and exhaust systems will require extensive design and fabrication.
2
Background:
Since this is the University of Maine’s first FSAE team, there is currently no data acquisition in
the car. Much research has been done in comparing the aforementioned loggers, and will be
explained in greater detail below.
Problem Definition:
The team plans to source a data acquisition system that will measure voltage levels across
various sensors throughout the FSAE vehicle. The voltage values over time will then be saved to
a compact flash memory card, as well as displaying select sensor data in real-time on an LCD
screen which is mounted on the vehicle. This system of data collection will give the team an
excellent tool for monitoring performance of the vehicle under driving conditions, and allow us
to make immediate adjustments that will improve the vehicles performance.
The data acquisition system must meet the following requirements:
Must collect data from multiple sensors (at least 12 inputs)
Must have at least 100Hz sample rate
Must save data to a compact flash memory card
Saved data must be analyzable by a computer program
Concepts:
Research of three separate data acquisition options was conducted. The first option was the pre
built and ready out of the box DL-1 logger with the Dash2 option. The second was a ground-up
Arduino unit. The third option was the DataMite II, another ready out of the box unit.
Options:
Race Technology DL-1 with Dash2 Option:
The first option that was considered was the Race Technology DL-1 data-logger with the Dash2
display screen option. Through contact with Race Technology, it was determined that many
teams run this unit with great success.
Figure 1: Race Technology DL-1 and Dash2 package. Source: Race Technology. “DL-1 and
Dash2 Package”. http://www.race-technology.com/dl1_dash2_package_8_7554.html. 25 Oct.
2011 <http://www.race-technology.com/dl1_dash2_package_8_7554.html>.
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Features of the DL-1 data-logger include [1]:
Built in GPS. The GPS unit is based on high accuracy GPS3 technology and calculates
position and speed 5 times every second. This is easily the fastest, most accurate GPS
system available for under $1500 (according to Race Technology). The measurements
from the GPS and accelerometers are combined to calculate very high accuracy positions
and speeds at 100 times per second.
Build in accelerometers. Built in 3-axis accelerometer with 2g full scale (optional 6g
full scale available)
Memory. Logging to compact flash memory card. This format is economical and ideal
for use in data logging products.
8 analog inputs. The DL-1 has 8 very high accuracy analog inputs. One of these is
connected to the DL-1 power supply used to measure battery voltage, and the other seven
are available for connection to external sensors.
2 RPM inputs. The DL-1 has 2 RPM inputs, only one of that is available for use at any
one time. One input is designed to be connected to “high level” sources, such as HT
leads or the ignition coil. The other input is designed for low level signals such as a feed
from the ECU.
4 wheel/shaft speed inputs. The DL-1 features 4 totally independent wheel/shaft speed
inputs. These can be used to measure the speed of all four wheels.
Lap beacon input. For some applications it is desirable to use a lap beacon. This
channel can also be used as a general-purpose digital input if required.
Small and tough. The DL-1 is just 110mm x 75mm x 30mm, and can be fitted into a
small motor bike or go kart. The DL-1 is housed in a robust enclosure, for very high
impact resistance.
Simple operation. A single button to start or stop logging.
Software. The DL-1 comes with a data analysis software package.
Due to the DL-1’s extensive options, programmability, and ease of use, at this point in the
analysis it seems to be the most logical choice for our FSAE team.
Ground-Up Arduino:
The second option that was researched was the building of a data acquisition system from the
ground-up. The central processor that was chosen was the Arduino. The main reason for
selecting this device is its price, since team members are not familiar with the building and
programming of the unit. The Arduino features removable compact flash memory, optional
accelerometers and GPS add-ons, as well as a programmable sample rate. The main problem lies
where the self built unit does not feature an included software package for data analysis.
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Figure 2: Arduino central processor. Source: Maker Shed. “Arduino
Uno”. http://www.makershed.com/product_p/mksp4.htm 2010. 25 Oct.
2011. <http://www.makershed.com/product_p/mksp4.htm>.
Features of the Arduino include:
Memory options. The Arduino features a removable compact flash card type memory
system.
Inputs. The Arduino features a user defined amount of analog inputs.
GPS. The Arduino can be fitted with a GPS unit, but it must be purchased and installed
separately. Like the accelerometers, they are not included with the base unit.
Accelerometers. The Arduino can be fitted with accelerometers, but they must be
purchased and added separately. They are not included with the base unit.
Lap Beacon. With the Arduino fitted with a GPS, it could be programmed to include a
lap beacon feature.
Complex operation. Unlike the other two options, the Arduino must be completely user
programmed, and could take lots of time to debug and get to work correctly.
Software. Since the Arduino is a completely user designed and built unit, it does not
have an included software package. Any software package must be programmed.
Performance Trends DataMite II:
The third option that was considered was the Performance Trends DataMite II. Similar to the
DL-1, the performance trends is a ready out of the box unit capable of a 200Hz sample rate.
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Figure 3: DataMite II. Source: Performance Trends. “30 Channel
DataMite II”. http://performancetrends.com/dtm-hdwe.htm. 25 Oct. 2011.
<http://performancetrends.com/dtm-hdwe.htm>.
Features of the DataMite II include [2]:
Memory options. The DataMite features removable compact flash card type memory.
Inputs. The DataMite features 3 RPM channels, and 12 analog channels.
GPS. The DataMite features a built in DT3-GPS unit allowing for GPS track mapping
and lap timing for road racing/ circle track systems.
Accelerometers. The DataMite features 2 built in accelerometer channels.
Lap Beacon. The DataMite is capable of calculating lab data with its GPS system. Also
includes reaction time.
RPM inputs. The DataMite II features 5 RPM inputs (engine, front and rear wheel,
driveshaft, supercharger, etc.)
Simple Operation. A single button is used to power on the unit, and it features a “Power
ON” led light, as well a recording led light which flashes each time a sample is written.
Small. The DataMite II’s mounting flange is 170mm x 200mm, and the unit is about
50mm thick.
Software. The DataMite comes with a software package capable of analyzing the
recorded data.
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Economic Analysis:
In doing a cost comparison of the three options it was found that the Arduino is the most
economical as shown in Table 1 below, with the DataMite II coming in second, and the DL-1
being the most expensive. This table shows approximately how much it will cost to get each
base unit up and running, not including minimal costs of sensors that are not already on the
vehicle, which would have to be purchased to obtain certain data. Since all sensors and
expansions are additions to the totals of the three, it is only necessary to show the cost of the base
units. This, however, is not taking into account the time that would be required in building and
programming the Arduino, or the troubleshooting of all three.
Table 1: Economic Analysis
Features
Race Technology DL-1
Ground-Up Arduino
Unit
LCD Screen
Total
$859.00
$865.00
1399.00 (package deal)
$300.00
$80.00
$380.00
Performance Trends
DataMite II
$1200.00
$80.00
1280.00
Final Decision:
In doing the analysis of these three data acquisition systems, the team has come to the conclusion
that even though the DL-1 and Dash2 option is the most expensive of the three, it will give the
team the greatest amount of options and usability, and because of this will give the team more
time to focus design efforts on other key elements of the vehicle, such as intake and exhaust.
Another benefit of the DL-1 is that it can be used by the suspension team, as well as the drive
train team via the wheel speed sensors which will greatly aid in the design and troubleshooting of
these two major components of the vehicle.
Another advantage of the DL-1 and Dash2 is that it comes with a data analysis software package
that has been successfully used by many FSAE teams in the past. Though the DataMite also
comes with a software package, no evidence could be found that it had been used by teams in the
past, or that it had been a successful option. The software package option was one of the biggest
downfalls of the Arduino as the team would be required to develop a useful data analysis
program in order to get the full usefulness of the unit.
Possibly the biggest deciding factor in choosing the DL-1 over the other two units was its
usability. Though the DataMite was also a ready out of the box unit, it did not come with a pre
programmed display screen. The team felt that this would be a major problem due to our lack of
computer programming skills. This is where all of the problems with the Arduino lied as well.
The team decided that building a ground-up unit that would have to be completely programmed
for countless hours would not be a practical option at this time.
7
References:
[1] Race Technology. "DL1 Data Logger." DL1 Data Logger. Race Technology. Web. 25 Oct.
2011. <http://www.race-technology.com/upload/DL1_Dsheet.pdf>.
[2] Performance Trends. "30 Channel DataMite II." 30 Channel DataMite II. Performance
Trends. Web. 25 Oct. 2011. <http://performancetrends.com/dtm-hdwe.htm>.
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Appendix A:
Data Logger Grade Sheet:
Table 2: Data Logger Comparison Grade Sheet, Score Out of 100
Race Technology
DL1
Performance
Trends
DataMite II
Arduino
100
50
100
100
100
100
Accelerometers
100
100
90
GPS
Sample Rate For Auxiliary
Inputs (100Hz Desired)
100
100
90
100
100
100
Lap Beacon
100
100
80
12v Power Supply
100
100
100
Durability (Factory tested)
100
0
0
Optional LCD Screen
Programmable Warning
Lights
100
100
100
100
0
100
Included Software
100
100
0
Pre Built
Trouble Shooting
(customer support from
manufacturer)
Software Interface
(Programmable)
100
100
0
100
100
0
100
100
100
Price
30
30
100
Score
95.33
78.67
70.67
Memory Options (SD
Card)
External Inputs (12
desired)