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FSAE i2 Data Analysis Seminar

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FSAE i2 Data Analysis Seminar
FSAE i2 Data Analysis Seminar
Software Download & Installation
• MoTeC software is available for download from the
website at:
http://www motec com au/software/latestreleases
http://www.motec.com.au/software/latestreleases
1
i2 Standard vs i2 Pro
i2 Standard
• Single overlay lap
• Simple maths functions
– Corrected speed / distance
– Filter, scale and offset
– +-*/
• 15 Worksheets
• 5 time/distance graphs
• 10 Channels per graph
• 5 Outing graphs
• 2 Histograms
• 1 Scatter plot
• 1 Mixture map
• 1 Track Report
• Section Times
i2 Pro
• Multiple overlay laps
• Advanced mathematics
–
–
–
•
•
•
•
•
•
•
•
•
user maths
global maths
flexible Expressions
Unlimited display components
Unlimited workbooks
Unlimited worksheets
User definable track sections/sectors
Lap Reports
Statistics zoom
Suspension Analysis
Video
Multiple projects
Program
ƒ
Basic i2 Introduction
ƒ Reliability and Safety
ƒ Evaluating Driver Performance
ƒ Evaluating Chassis Performance
ƒ Data Maintenance
2
Basic i2 Introduction
Getting Started
• Projects
3
Creating a New Project
To move, save or copy a project, simply move that
folder and everything but your data goes with it. Math,
graphs, etc…. On the new computer, it won’t
won t
automatically show in the recent project list so you’ll
have to “Open an Existing Project” the first time.
Open a Log Data File
5 ways to open files:
1) Pull-down menu
“File / Open Log File”
2) Ctrl – O
3) Icon on toolbar
4) F8, then Icon
5)) F8, then right-click
Open file dialog and icons
4
Data Window
• Lap Selection
FILE DETAILS
ƒ M
Main
i
ƒ Overlay
ƒ Other overlay
laps
Venue Event
Venue,
Driver, Vehicle
Date, Session
Time, Comment and
Filename
Lap List
Other overlay laps
Overlay 0
Main
Workbook Setup
Worksheets should be grouped into workbooks by their type, such as Engine,
Driver, Chassis, Suspension… or they can be grouped for different people such
as Engineer, Driver A, Driver B, Team Owner.
Worksheets
Workbooks
5
New Workbook
New Worksheet
6
Adding Components
•
‘Layout – Add’ menu
•
Right click on blank area of worksheet
•
Available Components:
•
Time / Distance Graph
•
Outing Graph
•
Histogram
•
Suspension Histogram
•
Scatter Plot
•
Mixture Map
•
FFT
•
Video
•
Track Report
Track Position
•
•
Rainbow track map
•
Time Report
•
Channel Report
•
Gauges (various types) ->
Add Time / Distance Graph
7
Adding Channels
View properties of the
selected
l t d channel
h
l
Category or Alphabetic
view still applies
S
Search
h th
the channel
h
l lilistt
Channels Window
• Category Alphabetic
Order
• Category Logged Order
• Alphabetic List
• Channel Properties
• Search Box
• Categories
8
Zoom Functions
•
•
•
•
Mouse scroll
Keyboard shortcuts
Scroll bars
Zoom Icons
Horiz Zoom out full – F2
Zoom to cursors
Horiz Zoom Default - W
Zoom
window
Vert Zoom out full
Zoom in Horiz
Double click and
drag to zoom
Vert Zoom in
Zoom out Horiz
Vert Zoom out
Zoom & Pan
Resize & Slide bar to Zoom & Pan
Icon
Shortcut
keys
Arrow
keys
Double Click, Drag & Click
If you accidentally double click, hit “Esc” key
Double click
to zoom out
vertically
To Zoom: use scroll wheel
To Pan: slide bottom x-axis
9
Time / Distance Graph 1
Lap select, Zoom and Scroll X axis
Channel
name
Min Max Avg
Value at
cursor
Time / Distance Graph 2
Active Channel
mark
F9 toggles the
Time / Distance
axis
Rescale / Vertical Zoom
group with active channel
by dragging arrows
10
Resizing and Layout
Click left corner
to move
Click and drag
edges to resize
Click and drag Splitter
to resize Groups
Values Box
Hide/Show Track Map
Show difference between
Main and Ref laps
Time and Distance at Cursor
Channels on the graph.
box = active channel
Values of all channels.
11
Datum Cursor
Show differences between
2 points on a graph
Graph Properties 1
• Creating a graph
• Channels
• Groups
12
Graph Properties 2
Display
• Title
• Layout
• Info Options
• Options
• Cursor
• Trace
Channel Properties
• Unit
• Decimal Places
• Colour
Edit
Channel
Colour
Scheme
• Up Sampling
• Scaling
• Info
13
Channel Options on a Graph
•
•
•
•
•
•
•
•
•
Hide
Remove
Edit Maths
Filter
Scale / Offset
Zero at Cursor
Previous
Next
Channel Properties
Maths
•
Simple Maths Functions (Filter , Scale & Offset)
A number of simplified maths functions are provided to avoid the need
to use the expression editor for simple operations like Filtering and
Scale & Offset. All other functions must be performed using the
Expression Editor. Note that these functions modify the original channel
– they do not create a new channel. To create a new channel use the
corresponding functions in the expression editor.
14
Example Maths Expression
‘Brake Pres front’ [psi] / (‘Brake Pres front’ [psi] + ‘Brake Pres Rear’ [psi])
Type Maths
Expression
Old Method of Data Analysis
15
New Method of Data Analysis
Download the data every time the car enters
• Begin with the vital channels such as:
• Engine temps, pressures
• Battery voltages
• Then look at the performance data
• Listen to the driver
• Observe first what the car is doing and then try
to understand why
•
Reliability and Safety
16
Program
ƒ
Channel Reports
ƒ Temperatures
ƒ Pressures
ƒ Battery Voltages
ƒ Useful Tips
Using the Channel Reports
Main and
reference
lap details
All laps channel
report
Selected laps
(main and
overlay)
channel report
Selected laps
channel
h
l report
by sectors
17
Zoom out to Entire Run
Temperature Sensors
Three major types of sensors:
• Thermistor
• Thermocouple
• Infrared
18
Reading Temperatures
Max Engine Temp
The maximum temps for
each channel by lap
Engine Temperature Problem
Engine Temp too high
19
Pressure Sensors
• Different sensors available in Absolute or Gauge
• S
Standard
a da d se
sensors
so s ranges
a ges from
o 0 – 2000
000 PSI
S
• Can measure Fuel and Oil Pressure
Reading Pressures
Pressure summary per lap
20
Oil Pressure Problem
Fuel Pressure Problem
Fuel Pressure low
21
Reading Battery Voltages
Battery Voltage looks noisy
Useful Tips
Max and Min lines in blue and red
Oil Pressure decreasing with Engine Temp
Battery voltage now looks fine
22
Annotations
Evaluating Driver Performance
23
Driver Analysis Channels
•
•
•
•
•
•
•
Engine RPM
Wheel Speed
Comparing Laps
Throttle Position
Steering
Lateral and Longitudinal G
Brake Pressure
Reading Engine RPM Trace
Upshift
Downshift
Braking
Straight
Wheelspin
Corner
24
Wheel Speed Sensors
• Toothed wheel and sensor arrangement
• Accurate calibration in Dash/ECU software is required
Measurement
Sensors required
Vehicle speed
Wheel speed
Lap by lap speed
Wheel speed, lap
Outcome
Top speed, minimum corner speeds, corrected
ground speed, corner
Compare each lap for speed, overlay to find
comparisons
beacon
driver mistakes or faster race lines
Wheel lockups under
Wheel speeds, front
Brake locking into corners, help determine
braking
Driven wheels slip
Gear selection trace
Track Mapping
and rear
Wheel speeds, front
and rear
Wheel speed, RPM,
performance, find the slip ratio of the driving
wheels
Create accurate gearing charts to see whether
throttle position
gear selection is correct, driver analysis
Wheel speed,
Create visual representations of the track for
Accelerometer,
reference when examining data, virtual
Beacon
Driver analysis
incorrect setup
Diagnose traction problems, evaluate driver
Wheel speed, G
sensor
segment time.
Extensive driver analysis through lap overlays,
minimum and maximum speed comparisons,
and accelerating/braking efficiency.
Reading a Wheel Speed Trace
Each wheel
speed value
at the cursor
The Min,
M
Max,
A
Average
wheel speed
values
The four wheel
speeds overlayed
against each other
1Hz GPS Speed trace
25
Comparing Laps - Overlays
Reference
Lap (Black)
Faster
Main Lap
(Red)
Where Did I Lose Time?
Where
biggest gain
is made?
Higher
minimum
corner speed
d
Brakes being
released
26
Overlayed Track Map
Both cars as they compare to
each other in that part of the lap
Throttle Position Sensors
Accelerator
cable
Pedal
Measurement
Sensors required
Outcome
Throttle position
Throttle
Use of the engine,
Throttle histogram
Throttle
Time at full speed
Average throttle
Throttle
Throttle speed
Brake position
Brake speed
Linear
potentiometer
Clutch position
Driver analysis
Throttle
Quantify handling
See the agressivity of the driver on the
throttle/pedal
Brake pedal,
See how the and when the drier
brakes pressures
brakes
Brake pedal
position
Braking speed, reactivity
Clutch position
Driver ability to change gears
Throttle, G sensor,
Extensive driver analysis through lap
RPM
overlays, acceleration timing.
27
Reading a Throttle Trace
This is where the
rear wheels have
lost traction
Here you can see
the driver lifting the
throttle to stop the
wheel spin
Steering Sensors
• Rotary Sensors.
• Interlocking geared teeth.
• Can measure steering wheel rotation.
28
Reading a Steering Trace
The steering
trace can be
visualised by
displaying it as
a gauge.
G Force Sensors
• Can be used to measure Acceleration, Deceleration,
Cornering and Vertical Forces
• It is important to mount the accelerometer at (as close as
possible), or directly below the centre of gravity.
29
Reading a G Force Trace
G Force long and
lateral alongside
braking and throttle
Reading Brake Pressure Trace
Brake pressures
and temps shown
both on graph and
as gauges for
clarity.
30
Driver Analysis Topics
•
•
•
•
•
Straight Line Acceleration
Braking Analysis
Understeer/Oversteer
Driving Line
Driver Consistency
Straight Line Acceleration
ƒ Race Starts, 0-100kmh and 0-400m times use Datum Cursor
31
Straight Line Acceleration
ƒ Duration of an Upshift use Datum Cursor
Wheel Spin
Following the wheel speed
traces here, you can see
wheel spin where the two
blue lines rise above the red
and orange lines, peaking at
12km/h front to rear speed
difference
32
Rate of Change Measurement
You can easily measure rate change using the Datum cursor. Below see the
acceleration (in KM/h/Sec) of a V8 Supercar at Phillip Island in 5th gear. You
should keep this number in mind when dyno tuning your car next time.
Throttle Histogram
33
Braking Analysis
Brake pressure reduction
Throttle blips
from heel and
toe braking
Brake Pressures
Rear brakes
locking
g up
p
Driver releasing
pedal to unlock
rear wheels
34
Brake Pressure Scatter Plot
Front/Rear brake
pressures zoom
linked to histogram
Calculated brake
bias channel
Of the 25,500
samples, most
pressures above
180psi exist
between 43%
and 55% bias
Brake Pressure Scatter Plot 2
Here is a brake pressure scatter plot from a poorly performing brake system
35
Wheel Lockup
In this slide, you can
see where the rear
right wheel speed
drops significantly
below the speed of
the front wheels
Understeer
Speed Increases
Slightly
Steering Increases leading to a
Smooth Understeer
Constant Lateral GForce
Throttle lifting by
Driver
36
Oversteer
Rear wheel speed
here is 6km/h faster
than the undriven
fronts
The throttle is lifted
to reduce the wheel
spin
The steering trace
and
d gauge show
h
the
h
driver winding on
opposite lock
Driving Line Analysis
Accelerating
Cornering
This method maintains the highest “minimum corner
speed” possible through a corner. Driving the Traction
Circle is the fastest way through this corner.
Braking
37
Late Apex Line
When a corner precedes a long straight, it might be
better to NOT drive the Traction Circle. That is no trail
braking. A later apex results in a lower minimum
corner speed, but allows a faster exit speed. That
p
is carried down the entire length
g of
extra exit speed
the straight.
Variance
Speed
Higher minimum speed, but can’t
get on the throttle as early.
0.05 seconds slower in
middle of corner, but
0.15 faster down
straight.
TP
Net gain = 0.10 seconds
GPS Race Line Analysis
38
GPS Race Line Analysis
Driver Consistency
ƒ Use Time Report
Blue = fastest section times
Eclectic is the theoretical best lap time if you add up all of the fastest sections.
Fastest Rolling Lap
39
Section and Split Times
Corner
section times
for all laps.
All section
times for all
laps
Straight
section
times for all
laps
Times from
the split
beacons
from all laps
Split times
and section
markers for
selected lap
Evaluating Chassis Performance
40
Program
ƒ
Brake Temperatures
ƒ Linear Potentiometers
ƒ Suspension Analysis
ƒ Damper Histogram
ƒ Tyre Temperatures
Brake Temp Sensor
ƒ
Working temperature of
your brake
y
ƒ Are your ducts cooling
efficiently?
41
Brake Temp Analysis
ƒ
From the brake pad manufacturer – know the
temperature
p
range
g within the braking
g system
y
is
operating at its peak performance
ƒ
From the data we can see if we are achieving
the desired temperatures. Then decide what we
need to do with brake ducts
Brake Temp Data
ƒ
Entire race
42
Brake Temp Data
ƒ
Single Lap
Linear Potentiometers
• Standard lengths from 50mm to 200mm
• Uses include position measurement of
suspension, pedals, levers etc.
43
Installation and Calibration
• The most common installation configuration for
linear p
potentiometers is on the shock absorber
Suspension Analysis
In this example, the front suspension goes negative under braking. Therefore,
for suspension position, bump or compression is negative. This is the easiest
convention for people to follow.
44
Talk to the Driver
ƒ
The experience of your driver, the comments
that he gives and the way he feels the car will
all affect the analysis of the data.
ƒ
Is there a balance problem in just one corner?
Or is it in all ‘right handers’?
ƒ
Zoom into the corner(s) and look at what the
damper position is at each corner of the car
with relation to the G trace and other channels
Damper Histogram
To spend more time in a region, stiffen that region.
To spend less time in a region, soften that region.
Graph of “AMOUNT OF
TIME” spent at different
“DAMPER SPEEDS”
Low Speed
Rebound
High
Speed
Bump
High
Speed
A few tips about the damper speed histogram:
• It can really only be used for a whole lap (the
linear potentiometers must be in the same
position at the beginning and the end of the
damper analysis)
• Always use the same number of bins
• Use a Min and Max such that the whole shock
speed histogram covers 95% of the measured
shock speeds
• Always use the same numbers for the Max
and Min shock speed (for later comparison)
• The shape of the histogram should be
symmetrical
• The shock speed histogram can also be used
to tune the spring and Anti Roll Bar
• Always use the same scale on the Y axis (for
later comparison)
45
Damper Histogram Analysis
Example of gain made using
damper histogram analysis
Damper Histogram with
modified damper settings
Damper histogram with initial
bump/rebound settings
Tyre Temp Sensors
Ti
Tc
To
RIGHT TYRE
IR temp
Sensor
installation
Example of tyre
Temp installation
46
Tyre Temps Quick Guide
TINSIDE
<
TCENTRE
<
TOUTSIDE
Not enough camber, or too much toe in.
TINSIDE
<
TCENTRE
>
TOUTSIDE
Tyre pressure too high.
TINSIDE
<
TCENTRE
=
TOUTSIDE
Not enough camber, or tyre pressure too high and too
much toe in.
TINSIDE
>
TCENTRE
<
TOUTSIDE
Tyre pressure too low.
TINSIDE
>
TCENTRE
>
TOUTSIDE
Too much camber, or too much toe out.
TINSIDE
>
TCENTRE
=
TOUTSIDE
Too much camber, or tyre pressure too low and too
much toe out.
TINSIDE
=
TCENTRE
<
TOUTSIDE
Not enough camber, or tyre pressure too low and too
much toe in.
TINSIDE
=
TCENTRE
>
TOUTSIDE
Too much camber, or tyre pressure too high and too
much toe out.
TINSIDE
=
TCENTRE
=
TOUTSIDE
OK
Tyre Temp Sensors
On the right part of the graph, the temperatures are the ones as
seen in the pits when the car stops. On the left part of the graph,
you get an idea of what is really happening on the track.
47
Tyre Temp Sensors
Corner temps
Data Maintenance
48
Contents
ƒ
Weekend Checklist
ƒ Organising Log Files
ƒ Details Editor
ƒ Exporting Data
ƒ Summary Sheet
ƒ Setup Sheets
Weekend Checklist
Start of Weekend
•
•
•
•
•
•
Update Details Editor
Event – General comments about meeting or test session.
Venue – Track name and the directory to which log files will be placed (very important).
Vehicle – Update any changes since the vehicle last ran, including gear ratios.
Check Sensors
Use Monitor Active Channels or scrolling through the Warm-up page on the dash to check that
all sensor values are appropriate for that sensor and fix any that are wrong.
Zero Sensors
If required zero G Sensors, Suspension Sensors, Steering, etc.
Logging
Check that logging templates loaded are appropriate for the day. For instance a template
configured for race logging with slower rates and fewer channels than practice logging might be
loaded from the previous race.
Venue Dependant Variables
p for Lap
p Time Gain/Loss change.
g
Load new Reference Laps
Beacons and Lap Times
Make sure that the Beacon Receiver is on the correct side of the car, or GPS coordinates are
correct.
Before/After each session
•
Details Editor
Update any changes made to the vehicle and enter details about the session (practice,
qualifying, race, etc.).
At the end of the day
•
Make sure that you collect your Beacon Transmitter.
49
Organising Log Files
• Organising your logged data into specific
folders for events so y
you can access
them quickly
Organise by Venue and Year
In Dash Manager
you can setup the
directory that you
want all your log files
to go when you
download the data
View / Edit Details
5 ways to Edit Details:
File 1
File 2
1) Pull-down menu
“Tools / Details”
2) In the open file window
3) Icon on toolbar
4) Shortcut key “Ctrl-D”
5) “F8”, then icon
50
Edit Details
Chassis # or Car #, used for the
name of the Excel setup sheet.
Shows in open window
Doesn’t show in open window
Exporting Data
•
•
•
•
Export to Matlab, .csv file or to the clipboard for use in Excel, etc.
For “Component” export, only the channels shown get exported.
For “File” export, all channels get exported.
All data is exported at the same rate.
Exporting to .ld file allows you to share your
data with another competitor but only the
channels you have graphed.
51
Exporting Channel Report Data
Creating a Summary Sheet
• Export the channel reports and paste in Excel.
52
Setup Sheets
•
Excel sheet for importing constants to be used in math equations, which
can vary by session. This file can be located anywhere, just make sure you
enable macros. Exit Excel once finished making changes.
You must enter
the date & time
of your
download.
You can delete columns which aren’t in
use. You can create your own columns,
names and select units.
Roll equation uses “Track Front & Track Rear”
You can leave blanks where the value
doesn’t change from session to
session.
Keyboard Shortcuts
See the Help File for
a complete list of
Keyboard Shortcuts
53
Keyboard Shortcuts
Keyboard Shortcuts 2
54
Keyboard Shortcuts 3
Keyboard Shortcuts 4
55
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