Bath Tub Lift Amos Baptiste Jeremy Czeczulin Andrew Hughes - - PowerPoint PPT Presentation
P14006 Bath Tub Lift Amos Baptiste Jeremy Czeczulin Andrew Hughes Richard Prilenski Introductions Name Major/Role Amos Baptiste Industrial & Systems Engineer/Team Leader Jeremy Czeczulin Mechanical Engineer/R&D Andrew Hughes
Amos Baptiste Jeremy Czeczulin Andrew Hughes Richard Prilenski
Name Major/Role Amos Baptiste Industrial & Systems Engineer/Team Leader Jeremy Czeczulin Mechanical Engineer/R&D Andrew Hughes Mechanical Engineer/CAD Designer Richard Prilenski Mechanical Engineer/FEA & CAD Designer
Description:
with physical disabilities, including limited balance, coordination, or mobility Objective:
the current device does not meet her needs
use/clean, makes minimal noise, and takes into account physical limitations of user
privacy
DeBartalo, Hospitals (RGH), Nursing Homes, suppliers/vendors, individuals recovering from knee surgeries, Linak, Klein Steel, SpringField Marine Company, McMaster Carr, and SeaSuckers.
ID Part/Component Weight (lb.) Material 1 Actuator 5.8 2 Control Box 1 3 Control Box Remote 0.7 4 Battery 6.2 5 Slider 5.5 6 Seat 7.2 Low density polyethylene 8 Slider Mount Screws 0.2 Stainless Steel 9 Charger with Cable 1.5 10 Suction Cup (4) 6.8 Stainless Steel and Plastic 12 Top Base 30 304 Stainless Steel 13 Bottom Base 35 304 Stainless Steel 14 Carriages 0.28 Steel 15 Rails (4) 3.75 Anodized Aluminum 16 Scissors Legs (4) 21.6 304 Stainless Steel 17 Actuator Clevis 1.43 304 Stainless Steel 19
0.184 Stainless Steel 20 Dowel 1.3 304 Stainless Steel 21 Bellow 0.5 Polyurethane 22 Adapter 1.3 304 Stainless Steel 23 Clevis (8) 7.576 304 Stainless Steel
Total Weight 137.82 Weight of Device 122.92
Stainless Steel Swivel
Commodore Seat (LLPE)
SeaSucker Suction Cups Linak Actuator with a Bellow McMaster Carr Rails and Carriages
Drawing and outcome of the scissor legs machined.
Dowel and actuator adapter.
Drawing and outcome of the base plate machined.
Drawing and outcome of the top plate machined.
Drawing and outcome of the clevis machined.
Component Cost Amount Left Material Vendor Turn Table $ 86.44 $ 1,948.20 Electrical Linear Acutator $ 193.95 $1,754 Linak Rechargeable Battery $ 63.96 $1,690 Linak Electric Control Box $ 107.51 $1,583 Linak Battery Charger $ 157.37 $1,425 Linak Remote Handset $ 84.05 $1,341 Linak Control Box Mounting $ 9.76 $1,332 Linak Charger Bracket $ 11.59 $1,320 Linak Main Cable $ 15.77 $1,304 Linak 4 1/2" SeaSucker $ 191.96 $1,112 SeaSucker Light Duty Seat Slide with Stainless Steel Swivel $ 98.76 $1,014 Stainless Steel Springfield Marine Company Seat $ 74.00 $940 Low Density Polyethylene Springfield Marine Company Ziploc Space Bag $ 13.39 $926 Walmart Home Depot Demo Purchase #1 $ 67.66 $858 PVC Pipes Home Depot Home Depot Demo Purchase #2 $ 43.78 $815 Home Depot Shipping for Swivel and Seat $ 25.00 $790 Springfield Marine Company Turn Table Returned $ (69.15) $859 3/8" 304 SS 15"X31" $ 134.00 $ 724.84 304 Stainless Steel Klein Steel 3/8" 304 SS 15"X24" $ 111.00 $ 613.84 304 Stainless Steel Klein Steel 3/8" 304 SS Plate 7"X22" $ 108.00 $ 505.84 304 Stainless Steel Klein Steel 1.5" 304 SS Plate 1.5" X 3" $ 44.00 $ 461.84 304 Stainless Steel Klein Steel 0.5" 304 SS Round 17" $ 12.24 $ 449.60 304 Stainless Steel Klein Steel PBC Linear Rollers Rail and Carriages $ 311.84 $ 137.76 Stainless Steel PBC Clevis (4) $ 172.00 $ (34.24) Cast Iron Cylinder Repair Componenets Bellow $ 67.13 $ (101.37) Polyurethane McMaster Carr 0.75" 304 SS Round 17" $ 27.00 $ (128.37) Stainless Steel Klein Steel McMaster Carr Rails and Carriages $ 288.92 $ (417.29) Steeland Anodized aluminum McMaster Carr
$ 10.74 $ (428.03) Stainless Steel McMaster Carr Total Spent $ 2,462.67
the acting forces on the base plate and each is 100 pounds which adds up to a total of 400 pounds of force.
used was 304 stainless steel where its yield stress values are 36 ksi.
concentrations occurred at the welded spots on the four ends of the base plate where it was 4.564 ksi which is significantly below the 36 ksi limit.
suction cups at each end of the base plate. The displacement
base plate where it underwent a natural bending motion.
noted at 0.007” which is very low for 304 stainless steel. The maximum acceptable limit would be 0.035”.
along the base plate which ranged from 2.55 all the way to 15. Probes were taken to better portray the safety factor values in various locations on the base plate where stress concentrations were the highest.
factor values were to be at least 2. The lowest which was 2.55 and in
to fail, the total acting forces would have to exceed 1,020 pounds which highly acceptable.
The total load value was 350 pounds. The maximum stress that
limit.
The maximum displacement values were roughly 0.005” which successfully passes the deflection test for 304 stainless steel. (The maximum displacement limit is usually 0.035”).
The safety factor values that are along the rod supporting the load. The stress concentrations occurred close to the pin ends by the clevises and also by the rod adapter piece. The lowest safety factor value was 2.51 which is satisfactory. The desired safety factor range for this project is 2-4.
Problem Number Identifying & Selecting Problem PSP 1 Analyzing Problem PSP 2 Generating Potential Solutions PSP 3 Selecting & Planning Solution PSP 4 Implementing Solution PSP 5 Evaluating Solution PSP 6 R1 R2 R3 Y4 Y5 G6 1 Height of the chair Actuator extends out too much the chain will surpass the required height. Code the actuator to stop at a certain point instead of when it is fully extended Apply a stopper on the rollers using the suction cups steel base to stop the rollers from going off track and the actuator from pushing the height any further Weld blocks to stop the actuator from extending out. 2 Actuator failing to operate Actuator not waterproof
cover actuator.
actuator waterproof. Cover the actuator with a bag to make it waterproof. Vacuum sealed Ziploc bag which can cover the actuator and try with demo. Ziploc bag doesn’t hold seal once a hole is placed for wiring. Bellows are now in consideration and will be tied
3 Can't tell if the battery is charging Depending on position/eye level with battery you can tell if it is charging.
user.
LED light to increase the brightness. Mount the charger eye level to the user during the time of customer visit. While meeting with customer slightly test by attaching the charger to the wall and see where the it may be positioned. 4 Actuator won't start Battery is dead due to user negligence.
when it is low on battery.
low on battery for user safety. Have the battery not operate if it is low on battery for user safety The actuator will go back to its neutral position Neutral position of the actuator is when the seat is up and will not
5 Weight of the battery User has limited strength/arm capabilities
not above the users shoulders.
station where is can be installed while sitting.
battery once a month. Amos look into ergonomics of the weight of the battery Have user have someone that could help once every 2 weeks to help with charging the battery Communicated with Theresa that the battery will need to be replaced by
request. 6 Mounting bracket won't install correctly Mounting bracket is bent
the Brinkman Lab.
sent. Bend the mounting bracket at the Brinkman Lab. Have the mounting bracket be bent back by the Brinkman lab and ensure it is straight. Mounting bracket was sent to the Brinkman lab where it was bent back to its original position. 7 Device secured to the tub Exceed load capacity
tipping of the bathtub lift. Get vacuum powered suction cups from Seasuckers Testing suction cups forces by calculation and with demo From calculation the suction cups do very well and can withstand a load from a 350 lb. person 8 Device legs buckling while raising the user up Material and surface area of the beam
calculations from stress analysis.
conduct a stress test. Richard run stress calculation and confirms material and surface area Increase size of legs to 0.4" A36 Hot Rolled Steel Device Legs buckling reduced and has a safety factor of 2.427 which is in the 2-4 range 10 Force to rotate the light duty swivel Bearing in the turn table is tight
make it easier to rotate Apply a water based lubricant on the bearing to make it rotate easier. A sample lubricant was found in the suction cup shipment that was meant for bearings and is waterproof. Lubricant was applied to the bearings
After a week of letting the lubricant settle in the chair moves more freely now with less resistance. Plan to have client test if it would need more.
Problem Number Identifying & Selecting Problem PSP 1 Analyzing Problem PSP 2 Generating Potential Solutions PSP 3 Selecting & Planning Solution PSP 4 Implementing Solution PSP 5 Evaluating Solution PSP 6 R1 R2 R3 Y4 Y5 G6 11 Suction cups not coming after order Sales representative not available and white suction cups sold out
call Seasuckers Team get in contact with Seasucker and Chris from MSD office Contacted both Chris and Seasucker sale representative. The suction came in. Delay in order due to sale representative being out for the week we wanted to place
12 Finding bellows for our needs Customizable bellows have to be bought in bulk
a single order can be placed for the school Search for another vendor that the bellow can be ordered from . Contacted McMaster Carr for a bellow and took the bellow to the machine shop where we used wire to tighten each side. Bellow with wire tying of each end create it to be watertight compared to using a hose clamp. 2nd wire was added on each end to help reinforce. 13 Budget for BOM Miscommunication on budget between team and administration. High costs due to stainless steel parts needed.
reasoning Contact advisor and ask for a readjusted budget Have advisor talk with Chris and Mark about budget for team to get more money Budget expanded to purchase more parts to finish prototype. 14 Round bar not strong enough A bar with 1/2" diameter was ordered and after seeing the weight of the bases that will add stress on the bar with the weight
thickness of the
Buy a bigger bar from Klein steel to replace the original bar. Contact Klein steel for the same bar but with a 3/4" diameter in exchange for the 1/2" diameter rod. Klein steel was contacted on (11/10/14) and we cannot exchange
and pick up a new one. New bar was purchased and delivered from Klein Steel. This bar was machined to the component to attach to the actuator and passed stress analysis. 15 Rollers lead time Rollers from Motion Industries promised to come in by 11/7/14 but did not ship out until 11/11/14 Try to expedite shipment or pick it up
lead time Contact Chris Fisher to contact the supplier on how to speed the delivery process The rollers will delivered on 11/13/14 which will be under watch by Chris for a notification for its arrival for the team to pick up. With the late delivery the meeting with Theresa had to be pushed back to next week 16 Drawings to water jet base plate Need rollers to help make drawings to place in the water jet machine Get drawings on the rollers to help with the drawing for the base. Will leave this aspect last so when the rails and carriages come in an accurate drawing can be made and sent to the Brinkman Lab to machine the base. Receive rails and carriages from McMaster Carr and updated water jet drawings. Top and bottom plate were cut with water jet using scrap material for
17 New CAD drawing of final product Need to make drawing for seat and slide in Inventor Contact vendors for their drawings to upload into the assembly Contact vendors for drawings and look for drawings online that look similar to the components purchased. Called vendors and received no response or ability to not release drawings No response from vendors on the drawings and will have to make the drawings from scratch to best represent the final device. 18 2 Clevises are too big With the height of the rollers and the height
mismatch in height between all the other clevises attached to the base.
clevises for smaller ones
material and attaching it from underneath Contact vendor to exchange the clevises for new ones and increase the height of the smaller clevises are will not be welded on to the rollers. Vendor was contacted and new clevises were delivered. All the clevises work with the system. Some are tighter between the gaps which means the legs have to be machined down more to fit.
Problem Number Identifying & Selecting Problem PSP 1 Analyzing Problem PSP 2 Generating Potential Solutions PSP 3 Selecting & Planning Solution PSP 4 Implementing Solution PSP 5 Evaluating Solution PSP 6 R1 R2 R3 Y4 Y5 G6 19 Meeting original customer deadline (11/13/14) Parts are not in yet to finish assembly and human testing not conducted Reschedule meeting with Theresa for another week. Call Theresa and explain the situation and reschedule Appointment was rescheduled to the next Thursday (11/13/14) and then rescheduled again until further notice. Team has an extra a week to conduct testing and troubleshoot 20 Delivery of rails and carriages PBC Linear did not meet initial promise date from distributor and delivered rails but no carriages. When a sample was ordered the entire system was included. Contact PBC to return rails Purchase carriages from PBC Linear Purchase rails and carriages from another vendor Called PBC Linear and speak with a representative while looking at rails and carriages from other vendors. Called PBC Linear and spoke with a
returned and carriages were not feasible wit the budget or lead time. Rails and carriages were purchased from McMaster Carr and rails from PBC Linear will be donated to Senior Design office to add to surplus. With the new carriages the clevis will have to be drilled instead of welded due to the material difference from cast iron to aluminum. 21 Sitting height of the chair The chair sits too high when it is at it lowest position Purchase low profile rails and cut corners of the base to reset suction cup placement therefore reducing the sitting height Purchased low profile rails and cut the corners of the base to reset suction cups Cut out the corners of the base to rest the suction cups. The corner cut outs were welded on and the suction cups were placed underneath. Height of the seat decreased. 23 Having parts machined by the water jet. Water jet motor down. Wait for Water jet to be fixed Machine parts by milling Have the parts water jet outside of campus Wait for the water jet to be fixed Contacted Bonzo on when the water jet would be fixed and would be done before Thanksgiving. The parts were given down at the Brinkman Lab to be machined before the holiday. Water jet was fixed. The clevises, bottom and top plate were cut to size. 24 Unexpected machining needs Clevises and pin
sustainable when submerged under water Machine parts from top and bottom plate cut outs Design cut out from the top and bottom plate cut outs to machine and assemble Received help from Bonzo and Kraynak in the Brinkman lab to cut out parts and weld clevises. In addition machined remain scrap material from dowel to make pins.
Recommendations:
the device
actuator
stakeholders and requirements
role in producing the bath tub lift.
delayed the development of the device.
PVC demo