atv safety summit: vehicle tech innovations - determining rider-vehicle dynamics utilizing an atv...
TRANSCRIPT
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Determining Rider-Vehicle Dynamics
Utilizing an ATV Simulator
Charles Jennissen, MD
Gerene Denning, PhDDepartment of Emergency Medicine,
University of Iowa Carver College of Medicine
Salam Rahmatalla, PhD
Environment and Civil Engineering,
Jonathan DeShaw, MSEBiomedical Engineering
University of Iowa College of Engineering
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Background
University of Iowa and the College of Engineering has very strong computer modeling and simulator programs.
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Virtual Soldier
Santos, a high fidelity avatar
Biomechanical musculoskeletal modeling along with predicative dynamics technology
Can deliver feedback on how a certain type of task or combination of movements will impact a human's level of fatigue, speed, strength and torque over a period of time.
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Hank Virtual Environments Lab
Focuses on using virtual environments to study human perception and action.
Understand how children and adults negotiate traffic-filled intersections in our virtual environment.
Understand how people perceive and adapt to virtual environments.
Factors that put children at risk for getting hit by motor vehicles when crossing intersections
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National Advanced Driving Simulator (NADS)
One of the two most sophisticated driving simulators in the world.
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MiniSim
Harnesses the technological sophistication of NADS in a compact, customizable configuration.
Can be rapidly deployed for off-site or multi-sited research, population-specific assessment, or driver training.
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3D Bio-Motion Research Lab
Performs applied and basic research in human motion and biomechanics.
Moog ECU-624-1800 Electric Motion System
A tilt/vibration platform that is capable of acceleration of up to 15 m/s² in the longitudinal, lateral, and vertical directions. (Simulate Speed)
Can generate angular motion of at least 20 degrees in the roll, pitch and yaw directions. (Simulate Sloped Terrain)
Can vary vibration frequncies. (Simulate Rough Terrain)
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3D Bio-Motion Research Lab
Moog Electric Motion System
State of the art motion tracking equipment including a Vicon system with 12 SV cameras and a Motion Analysis system with 16 Eagle-4 cameras.
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ATV simulator
Bought a non-functioning Yamaha Bruin 4x4 ATV.
Stripped the tires and modified it so that the ATV could be secured to the motion platform.
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ATV simulator
Created a padded protective structure around the ATV that could be secured to the motion platform.
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Objective
Determine inter-individual variability in the biomechanical parameters of experienced adult operators with regards to operator/vehicle dynamics using an adult sized ATV simulator
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Subjects
6 adult males
18-45 years of age
Within one standard deviation of mean height and weight for an average adult male
≥100 hours of ATV operating experience
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Methods
Reflective markers were placed on the subjects (24) and on the vehicle (4).
Accelerometers placed on helmet and at C7
A series of seven programs were performed by each participant with changes at a variety of accelerations.
2 identical pitch programs (incline/decline)
2 identical roll programs (side hill/side to side)
2 identical vertical change programs (hole/bump)
1 program with all elements
Small vibrational motion in 6 degrees of freedom used as physical distraction and to mimic normal vehicle vibration
Movie of ATV riding through wooded area used as mental distraction
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Methods
Subjects were video recorded from the back and side.
Vicon motion capture system recorded motion of the subject from the pelvis and above
Motion data analyzed with Visual 3D™Software which is NIH approved
Pitching – Angle Between Torso and ATV
Side View
0 50 100 150 200 250 300 350 4000
10
20
30
40
50
60
70
80AVERAGE 4 Point: C7 to Pelvis to 4 Wheeler Angle
Cycle, Time = 2 Seconds
Angle
- (
Degre
es)
Sub1
Sub1 Repeat
Sub 2
Sub 2 Repeat
Sub3
Sub3 Repeat
Sub 4
Sub 4 Repeat
Sub5
Sub5 Repeat
Sub 6
Sub 6 Repeat
Rolling – Angle Between Torso and ATV
Front View Back View
*Measured degrees from verticalAngle from C7 to the center of the pelvis to
the ATV0 50 100 150 200 250 300 350 400
-30
-20
-10
0
10
20
30
40AVERAGE 4 Point: C7 to Pelvis to 4 Wheeler Angle
Cycle, Time = 2 Seconds
Angle
- (
Degre
es)
Sub1
Sub1 Repeat
Sub 2
Sub 2 Repeat
Sub3
Sub3 Repeat
Sub 4
Sub 4 Repeat
Sub5
Sub5 Repeat
Sub 6
Sub 6 Repeat
Future Studies
Will add pressure sensors on the handle grips, seat, and footrests to provide additional biomechanical measurements.
Conclusions
Our preliminary data provides proof-of-principle for using our simulator to study “active riding.”
Future studies include determining how factors such as gender, age, inexperience, and passengers influence rider-vehicle dynamics.
Simulator-based technology is a powerful and safe tool to address research questions related to ATV operation that cannot be tested using other methods.