Problem Definition
Sponsor Background
• Includes the Mercedes-Benz, Chrysler,
Dodge, and Jeep brands.
• Formed during merger of Daimler-Benz and
Chrysler Corporation in 1998
• American operations are headquartered in
Auburn Hills, MI
• Over 360,200 employees and $200.4 billion
in revenue as of 2006
MSU Team
Joe Affonso
Jimmy Chen
Nick Harrington Mike Nicley
Industrial Advisor
George Konstantakopoulos
Faculty Advisor
Dr. John Foss
Electrical Consultant
Shannon Nicley
Final Design
• The Infinite Position Door Check system will
hold a swing-type passenger vehicle door in
any opened position the operator desires
• This project will be initially modeled on a
production door from a Chrysler 300, but
should be scalable to any application within
DaimlerChrysler
• The final prototype should represent a
production-ready, inexpensive, and adjustable
design
• It will open and close identically to current
production doors, but without pre-set detents
• When stopped in any position, the door will
remain in position until its holding force is
overcome by the user, at which time the door
will swing freely
Final Design Assembly, SolidWorks Model
Design Specifications
Economic Analysis
• Hold door stationary at any user defined
position
• Product will initially be marketed as a luxury
option
• Perform similarly to current door check
systems
•Prototype component and material costs are
$53 per unit when commercial retail pricing is
used, not including labor or assembly
• Designed for lowest cost possible
• Dependable and reliable
• Safe during use, handling, and installation
• Add luxury to the users experience with the
automobile
• Eliminate door bumps which can occur when
a door “falls into” a pre-set detent
Initial Design Concepts
Prototype, Fully Mounted In-Door
Design
Recommendation
• The final design is electronically controlled
• During door movement, a position sensor sends a signal
to a microcontroller
• The control system then disengages a holding frictional
piece
• When the door is stopped and held by the user, the
signal from the position sensor turns off
• The control system then engages an electric motor
which is attached to a force multiplier
Centrifugal Clutch System
Electronically Actuated System
• The rotational motion is converted to lateral motion by a
scissor jack type force multiplier
• Shaft rotation causes one end of the force multiplication
truss to push a steel semi-cylindrical friction part against a
steel cylinder attached to the door hinge
Viscous Piston Cylinder
Prototype Hinge Portion, with Position Sensor
• When the user pulls on the door and overcomes this
holding force, the position sensor starts to move,
signaling the motor to release the holding force
• Market polling indicated consumer
willingness to pay an average of $200 per
door for this feature
• Total production cost is $34 per unit
• The frame, friction material, and pivot
cylinder could be mass-produced for a total
cost of $6 per unit
• Bulk purchasing of the motor, motor
attachment, and electronic components would
yield a total cost of $25 per unit
• Assembly and installation costs total $3 per
unit
Conclusions
• This design represents a feasible solution to
the problems posed in the creation of an Infinite
Position Door Check system
• Prototype is functional, despite power losses
which result in a smaller-than-desired holding
force
• Full-function, production-ready prototype can
be achieved with minor design changes and
increased component precision