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Adjustable Gold Metal Seat
MSDI Desired start: Winter 2012 MSDII Desired: Spring
2012
Project Description:
This project will take a current system that
allows a specific quadriplegic sailor, in a specific boat to
steer and make it adaptable to both different people
and boats. The system will consist of a seating support,
steering hand crank and tiller strut. The system will use
a sourced, adjustable seat. The seating location will be
adjustable from front to back and in height. The hand
crank location will also be adjustable front to back and
up and down as will the leg rests. The system should be
easy to install and lightweight.
Current tentative MSD team: 3 mechanical engineers, 1
industrial engineer, Richard Ramos as the primary
customer, Professor Leipold has a faculty consultant and
Mr. Burhans as a stakeholder.
Feasibility: This project has the interesting design issue of adding adjustability to all components of a
system. The project has been shown to be feasible by identifying major risks and mitigating them. An
example is the hand crank adjustability was shown to be feasible by evaluating the shear in an adjusting
pin and the “wobble” of the system.
Current system shown with adjustability
concepts.
Automotive Syle Seat Track
Rides on Screw such as bed on
lathe
Bolted connection with multiple
positions
Pinned Connection with multiple
connections
These forward and back adjustments would be valid for the leg rests
Forward and Back adjustments Bench Marking Table
These forward and back adjustments would be valid for the leg rests
as well as the seat.
Could be Purchased and added yes no no no
Easiy to implement to seat Yes no yes yes
Easy to implement to leg rests no no yes yes
Easy to adjust on the fly yes yes no yes
https://www.carpartsdiscount.com/auto/parts/68/chevrolet/camaro/seat/seat_track_lh_2pc.html?3593=4826
http://image.made-in-china.com/2f0j00weTQkoLPnMbB/Lead-Screw-and-Feed-Shaft-Lathe-WF230-1500-.jpg
Screw Jack System Pinch Clamp System
Bolted connection with multiple
positions Sissor Jack System
Pined Connection System
simular to bolted connection
These benchmarks are for current systems that have an adjustable
height. The portions of this project where these apply are the hand
crank, seat, and the leg rests.
Height Adjustablility Benchmarking Table
crank, seat, and the leg rests.
Allows for infinited adjusted positions Yes Yes No Yes No
Difficulty adapting to Seat Height Adjustment Dificult Medium Diffuculty Medium Diffuculty Easiest Medium Diffuculty
Difficulty adapting to leg rest and Hand crank Difficult Easy Easy Most Difficult Easy
Easy to adjust on the fly No Yes No Yes Yes
Photos:
http://www.google.com/imgres?hl=en&biw=1410&bih=914&tbm=isch&tbnid=Q0bi3-5h6ZOnaM:&imgrefurl=http://terryfurniture.co.uk/index.php/products/view/products2/34&docid=O3XGfeUUgIKZnM&imgurl=http://terryfurniture.co.uk/images/made/Cast_Iron_Stool_large_700_500_c1.jpg&w=700&h=500&ei=ZbOIUNiTOpTK0AG6lYH4Aw&zoom=1&iact=rc&dur=220&sig=102836474452851656036&page=1&tbnh=140&tbnw=203&start=0&ndsp=30&ved=1t:429,r:1,s:0,i:71&tx=125&ty=41
http://www.montaguebikes.com/assets/images/ownermanual/quick-release-seat.jpghttp://www.montaguebikes.com/assets/images/ownermanual/quick-release-seat.jpg
http://www.polopuentearanda.com/wp-content/uploads/2011/10/wpid-wpid-scissor-adjustable-height-table.jpg
http://minnesotamedical.com/minnesotamedical/images/74-15Km.jpg
http://www.pirate4x4.com/tech/billavista/Bender&Notcher/images/Bender/IMG_5642_resize.JPG
System Benchmark Table
Exhisting Tiller Bench Current Gold Metal Seat Adjustable Automotive Racing Seat
Allows Easy transfer of quadreplegic person from side to side of boat No Yes No
Seat is adjustable for comfort (different body types in chair) No No Yes
Requires no modification to boat No Yes Possible non modification interface
System allows quadreplegic person to steer boat No Yes Possible with adaption to current system
Photos from:
https://edge.rit.edu/edge/P12031/public/Planning%20%26%20Execution
https://edge.rit.edu/edge/R13031/public/Sonar%20Photos
http://www.wesellcarparts.com/store/ProdImages/megan/meganseatred.gif
http://www.recaro-automotive.com/us/product-areas/aftermarket-seats/product/expert.html
Concept 1:
Goals: Schematic:
Description:
Pros:
Cons:
Concept 2:
2) By starting with the track based system that Richard uses he will be able to give the team first hand
knowledge.
1) By building on the current system, the team will be more likely to have a successful project
1) By starting with an existing system, the team may have a good idea for a completely new system
that is not track based however if they are told to use the old system this idea may be lost.
Develop a completely new system that is of a trackless design. It would most
likely use a pre-manufactured seat
Potential Concept Solutions
Purchased Adjustable seat attached to a newly designed adjustable frame track
based system that is similar to the existing system.
The goal of this system is to use the existing seat as a
jumping off point. The designs of the original system
will remain but adjustability in both the seat and the
mounting will be added.
This system will use a pre-manufactured seat that has features such as adjustable headrest, lumbar
support, thigh extension, adjustable side bolsters, adjustable seat bolsters. One such seat is:
http://www.recaro-automotive.com/us/product-areas/aftermarket-seats/product/expert.html, This
seat would be mounted to a newly designed seat mount that is adjustable for height and front to back
distance. The leg posts and hand crank system would be similar to the current system, however they
would now be adjustable. Could use current u shaped track or investigate a straight track.
Goals: Schematic:
Description:
Pros:
Cons: 1)There may be too much stress for one mounting location (the pedestal). Even if a frame and
pedestal can be proven to be feasible, there may not be enough strength in the mounting of this to
the boat for this system.
This system would achieve the same functions as the current project however instead of having a
track for the seat to ride on, it would be mounted on a center pedestal. I envision there being a
counter weight 180 degrees from the seat. The seat would most likely be a premanufacted adjustable
seat, but it doesn't have to be. The seat mount would have front to back, and up and down
adjustments. The leg posts and hand crank system would be similar to the current system, however
they would now be adjustable.
1) By developing a new design it gives the students free reign to design a better product.
2) By having one center mounting location, this system may be easier to implement to different boat
types than the current track based system.
likely use a pre-manufactured seat
The goal of this system is to not use the track system
of the old project. Instead it is to use a only pedestal
mount for the seat.
Concept Seat Mount/Frame
Goals:
Pros:
Cons:
Potential Concept Solutions assuming Concept 1
2) System can be changed on the fly
1) All the adjustments add complexity for
the individuals installing the system.
2) adjustment systems add weight
Fully Adjustable track mount adapted from current design.
Adjustable Boat
Mount Concept 1
Fully adjustable system that has mounting for a bought seat that has
adjustability.
Description: Simular to current system
however there are provisions for all needed
adjustments. These are just some ideas.
Others could be implemented.
To take the existing system and build in
adjustability so that multiple users can use.
1) System can be adjusted to many
different users
Goals:
Pros:
Cons:
To have a system that allows mounting of
system in various boats without
modification to the boats.
Description: Similar to the current system
there is a plate that mounts the track to the
boat. The plate sits on the benches and
mounts to 4 hand grips. The hand grip
mounts are adjustable as they sit on a
track. Their bases also swivel and their
height is adjustable allowing adjustments
to be made in 3 axis's.
Fully Adjustable track mount adapted from current design. Mount Concept 1
1) No modifications to boat
2) This system would be quick to adjust
This system assumes that the boat has
hand holds.
Concept Seat Mount/Frame
Goals:
Pros:
Cons:
Potential Concept Solutions assuming Concept 1
Fully adjustable system that has mounting for the tiller strut. This is what
mounts the tiller so that the lines from the hand crank can control steering.
Be able to mount without modification in
various boats.
1) All the adjustments add complexity for
the individuals installing the system.
2) adjustment systems add weight, and if
pressure is used possible boat damage
Adjustable Boat
Mount Concept 1
Track mount adapted from current design for boats without hand grips. The
Catalina 22 is an example of a boat without handgrips.
1) Mounts in various boats
2) System would be easy to adjust
Description: The current system is bolted to
hand holds in sonar boats. These hand
holds are not present in new boats. This
system must either rely on pressure
mounts or an avaliable tie down etc. in the
mounting area. It is adjustable for width
and height.
Goals:
Pros:
Cons:
Mount Concept 1 Catalina 22 is an example of a boat without handgrips.
To have a system that allows mounting of
system in various boats without
modification to the boats.
Description: Similar to the current system
there is a plate that mounts the track to the
boat. The plate sits on the benches and
relies on pressure pushing on the sides of
the boat to hold in in place. This could be
accomplished by either a screw system or a
piston system.
This system risks damage to boats if too
much pressure is applied
1) No modifications to boat
2) This system would work on a boat with
or without hand holds
Engineering Analysis Further work:
Boat dimensions:
To overcome the issue of not being able to find measurements of other boats, a concept that did not
rely on specific hand hold locations was developed. This concept will still require general boat
dimensions to be obtained by the senior design team however it is much more forgiving than a system
that mounts to hand holds.
If this system does not work, it is possible that the team may have to drill and attach mounting brackets
to the boat. If this occurs an agreement between the team and the boat owner must be made. Also
research must be done on the proper way to seal the mounts. It is preferable that if the mounts must
be removed, a hand hold etc can be mounted in their place.
Feasibility of hand crank adjustment:
I chose to study a simple pined connection for this. I had first planned to download the previous team’s
cad files. Unfortunately they did not seem to be documented on their sight. The files were there from
the original design. I was able to get a crank height from these files. I then added roughly 3 inches to
this height and then I drew a rough proof of concept. The bottom beam is an extruded 3x3 square with
0.25” wall thickness. The inner beam is a 2.5x2.5 beam with .25’ wall thickness. The pin has a diameter
of 0.75”
My proof of concept is of a pinned connection. The pin was made out of A36 steel and both aluminum
extrusions were made from 6061 AL.
A loading scenario of 170lb applied at the top where the hand crank would be was applied.
Solidworks Simulation was used. The smallest standard mesh size was chosen and can be seen below:
Max Element Size 0.220341 in
Min Element Size 0.0734463 in
The following are screen prints from the FOS plots:
The important take away from this is that the factor of safety is never in the red or near 1 at any of the
holes or near the pin. The only place that it is at 1 is at the top which is to be expected as the force was
placed on the beam as an approximate location. In the real system this will be distributed through the
hand crank.
As the pin and surrounding area do not show a low FOS it can be concluded that this is a feasible way of
making the height of this system adjustable.
Shear Pin Analysis:
Feasibility of Track:
Last week I had identified that a 95 percentile mail of 255 pounds should be used.
This week I researched the weight of the proposed adjustable seat. It is 35.2 lb from:
http://www.recaro-automotive.com/us/product-areas/aftermarket-seats/product/expert.html
This gives a total estimated weight of 290.2 lb or 131.63 kg.
The previous team used 136 kg in their work. This leaves a difference of 4.4 kg.
It is safe to assume that the height and back and forth adjustment mechanisms will be under 4.4 kg or
roughly 9 lb.
The previous team did an extensive fea analysis.
For the seat hitting the stops at the end of the track the lowest fos was 1.659 at the hinge.
For the down and bow direction applied force of 1425 N and 25N respectively the factor of safety was
1.73, 2.67, 2.5 for various loading locations.
As these are all over 1 so the system can be said safe to use for a 95 percentile male.
It is important to note that Richard would be at the upper level of the safe usable person of this chair.
1
Appendix (PRP): Skills Checklist Project Name (tentative): Universal Gold Medal Seat
Checklist Completed by (name):
Evan Wozniak
For each discipline, indicate which skills or knowledge will be needed by students working on the associated project, and rank the skills in order of importance (1=highest priority). You may use the same number multiple times to indicate equal rank. Mechanical Engineering
1 3D CAD Aerodynamics
MATLAB programming CFD
2 Machining (basic) Biomaterials
1 Stress analysis (2D) Vibrations
1 Statics/dynamic analysis (2D) Combustion engines
Thermodynamics 3 GD&T (geometic dimensioning & tolerancing)
Fluid dynamics (CV) Linear controls
LabView (data acquisition, etc.) 3 Composites
Statistics 2 DFM
Robotics (motion control)
1 FEA Composites
Heat transfer Other:
Modeling of electromechanical & fluid systems Other:
Fatigue & static failure criteria (DME) Other:
Specifying machine elements
Reviewed by (ME faculty):
Industrial & Systems Engineering
Statistical analysis of data – regression Shop floor IE – methods, time study
1 Materials science Programming (C++)
2 Materials processing – machining lab
Facilities planning – layout, material handling DOE
Production systems design – lean, process improvement
Systems design – product/process design
1 Ergonomics – interface of people & equipment (procedures, training, maintenance)
Data analysis, data mining
Math modeling – linear programming), simulation Manufacturing engr.
1 Project management DFx -- Manuf., environment, sustainability
Engineering economy – ROI Other:
Quality tools – SPC Other:
Production control – scheduling Other:
Reviewed by (ISE faculty):
2
Electrical Engineering NA
Circuit design: AC/DC converters, regulators, amplifier ckts, analog filter design, FPGA Logic design, sensor bias/support circuitry
Digital filter design and implementation, DSP
Power systems: selection, analysis, power budget determination
Microcontroller selection/application
System analysis: frequency analysis (Fourier, Laplace), stability, PID controllers, modulation schemes, VCO’s & mixers, ADC selection
Wireless protocol, component selection
Circuit build, test, debug (scopes, DMM, function generators)
Antenna selection (simple design)
Board layout (some students) Communication system front end design
MATLAB (some proficiency) Algorithm design/simulation
PSpice Embedded software design/ implementation
Programming: C, Assembly (some proficiency) Other:
Electromagnetics (shielding, interference) Other:
Other:
Reviewed by (EE faculty):
Computer Engineering NA
Digital design (including HDL and FPGA) Wireless networks
Software for microcontrollers (including Linux and Windows)
Robotics (guidance, navigation, vision, machine learning, and control)
Device programming: Assembly language, C Concurrent and embedded software
Programming: Java, C++ Embedded and real-time systems
Analog design Digital image processing
Networking and network protocols Computer vision
Scientific computing (including C and MATLAB) Network security
Signal processing Other:
Interfacing transducers and actuators to microcontrollers
Other:
Other:
Reviewed by (CE faculty):