P14006 Bath Tub Lift. Amos Baptiste Jeremy Czeczulin Andrew Hughes Richard Prilenski

Transcription

1 P14006 Bath Tub Lift Amos Baptiste Jeremy Czeczulin Andrew Hughes Richard Prilenski

2 Introductions Name Amos Baptiste Jeremy Czeczulin Andrew Hughes Richard Prilenski Major/Role Industrial & Systems Engineer/Team Leader Mechanical Engineer/R&D Mechanical Engineer/CAD Designer Mechanical Engineer/FEA & CAD Designer

3 Agenda Review Problem Statement Stakeholders Final Prototype Bill of Materials Components Ordered Components Machined Stress Analysis Budget Problem Tracking Review/Recommendation Questions

4 Problem Statement Description: Bathtub lift A device that provides assistance to an individual with physical disabilities, including limited balance, coordination, or mobility Objective: Improve the current design of Theresa Loce s bathtub lift since the current device does not meet her needs Develop a powered lift that is sturdy, comfortable, easy to use/clean, makes minimal noise, and takes into account physical limitations of user Produce a product that the user maintains autonomy and privacy

5 Stakeholder(s) Primary Customer: Theresa Loce Contact: Secondary Customer (s): Wheel chair users/handicap public & Elizabeth DeBartalo, Hospitals (RGH), Nursing Homes, suppliers/vendors, individuals recovering from knee surgeries, Linak, Klein Steel, SpringField Marine Company, McMaster Carr, and SeaSuckers. Contact: Faculty Guide: Art North Contact: Sponsor (financial support): RIT

6 Final Prototype

7 Final Prototype

8 Bill of Materials ID Part/Component Weight (lb.) Material 1 Actuator Control Box 1 3 Control Box Remote Battery Slider Seat 7.2 Low density polyethylene 8 Slider Mount Screws 0.2 Stainless Steel 9 Charger with Cable Suction Cup (4) 6.8 Stainless Steel and Plastic 12 Top Base Stainless Steel 13 Bottom Base Stainless Steel 14 Carriages 0.28 Steel 15 Rails (4) 3.75 Anodized Aluminum 16 Scissors Legs (4) Stainless Steel 17 Actuator Clevis Stainless Steel 19 Misc. Hardware Stainless Steel 20 Dowel Stainless Steel 21 Bellow 0.5 Polyurethane 22 Adapter Stainless Steel 23 Clevis (8) Stainless Steel Total Weight Weight of Device

9 Components Ordered Light Duty Seat Slide with Stainless Steel Swivel Commodore Seat (LLPE)

10 Components Ordered McMaster Carr Rails and Carriages SeaSucker Suction Cups Linak Actuator with a Bellow

11 Linak Actuator System

12 Machined Components Drawing and outcome of the scissor legs machined.

13 Machined Components Dowel and actuator adapter.

14 Machined Components Drawing and outcome of the base plate machined.

15 Machined Components Drawing and outcome of the top plate machined.

16 Machined Components Drawing and outcome of the clevis machined.

17 Budget Component Cost Amount Left Material Vendor Turn Table $ $ 1, Electrical Linear Acutator $ $1,754 Linak Rechargeable Battery $ $1,690 Linak Electric Control Box $ $1,583 Linak Battery Charger $ $1,425 Linak Remote Handset $ $1,341 Linak Control Box Mounting $ 9.76 $1,332 Linak Charger Bracket $ $1,320 Linak Main Cable $ $1,304 Linak 4 1/2" SeaSucker $ $1,112 SeaSucker Light Duty Seat Slide with Stainless Steel Swivel $ $1,014 Stainless Steel Springfield Marine Company Seat $ $940 Low Density Polyethylene Springfield Marine Company Ziploc Space Bag $ $926 Walmart Home Depot Demo Purchase #1 $ $858 PVC Pipes Home Depot Home Depot Demo Purchase #2 $ $815 Home Depot Shipping for Swivel and Seat $ $790 Springfield Marine Company Turn Table Returned $ (69.15) $859 3/8" 304 SS 15"X31" $ $ Stainless Steel Klein Steel 3/8" 304 SS 15"X24" $ $ Stainless Steel Klein Steel 3/8" 304 SS Plate 7"X22" $ $ Stainless Steel Klein Steel 1.5" 304 SS Plate 1.5" X 3" $ $ Stainless Steel Klein Steel 0.5" 304 SS Round 17" $ $ Stainless Steel Klein Steel PBC Linear Rollers Rail and Carriages $ $ Stainless Steel PBC Clevis (4) $ $ (34.24) Cast Iron Cylinder Repair Componenets Bellow $ $ (101.37) Polyurethane McMaster Carr 0.75" 304 SS Round 17" $ $ (128.37) Stainless Steel Klein Steel McMaster Carr Rails and Carriages $ $ (417.29) Steeland Anodized aluminum McMaster Carr Misc. part (Nylon Bushings, Washers) $ $ (428.03) Stainless Steel McMaster Carr Total Spent $ 2,462.67

18 Bottom Plate Stress Analysis The four yellow arrows are the acting forces on the base plate and each is 100 pounds which adds up to a total of 400 pounds of force. The type of steel that was used was 304 stainless steel where its yield stress values are 36 ksi. The maximum stress concentrations occurred at the welded spots on the four ends of the base plate where it was ksi which is significantly below the 36 ksi limit.

19 Bottom Plate Displacement The fixed constraint positions occurred by the bottom of the 4 suction cups at each end of the base plate. The displacement occurred in the middle of the base plate where it underwent a natural bending motion. The maximum deflection was noted at which is very low for 304 stainless steel. The maximum acceptable limit would be

20 Bottom Plate Safety Factor The safety factor values 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. For this project the original accepted safety factor values were to be at least 2. The lowest which was 2.55 and in order for the base plate to fail, the total acting forces would have to exceed 1,020 pounds which highly acceptable.

21 Rod/Adapter Stress Analysis The total load value was 350 pounds. The maximum stress that occurred was 12 ksi which is significantly lower than the 36 ksi limit.

22 Rod/Adapter Displacement The maximum displacement values were roughly which successfully passes the deflection test for 304 stainless steel. (The maximum displacement limit is usually ).

23 Rod/Adapter Safety Factor 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.

24 Problem Tracking 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 R1 R2 R3 Y4 Y5 G6 Apply a stopper on the rollers using Actuator extends out Code the actuator to stop at a certain the suction cups steel base to stop the too much the chain will Weld blocks to stop the actuator from 1 Height of the chair point instead of when it is fully rollers from going off track and the surpass the required extending out. extended actuator from pushing the height any height. further 2 Actuator failing to operate 3 Can't tell if the battery is charging 4 Actuator won't start 5 Weight of the battery 6 Mounting bracket won't install correctly 7 Device secured to the tub 8 10 Device legs buckling while raising the user up Force to rotate the light duty swivel Actuator not waterproof Cover the actuator with the bag. Create and use accordion design to cover actuator. Apply a lubricant to make the actuator waterproof. Depending on Mount the charger eye level to the position/eye level with user. battery you can tell if it Attach a plastic piece in from of the is charging. LED light to increase the brightness. Have the battery making a sound Battery is dead due to when it is low on battery. user negligence. Have the battery not operate if it is low on battery for user safety. Have the charging station and battery not above the users shoulders. User has limited Place the battery and charging strength/arm station where is can be installed while capabilities sitting. Have someone help user charge the battery once a month. Mounting bracket is bent Exceed load capacity or unleveled surface on the tub. Material and surface area of the beam Bearing in the turn table is tight Bend the mounting bracket back at the Brinkman Lab. Contact Linak and have a new one sent. Get industrial suction cups. Side arm attachment to help prevent tipping of the bathtub lift. Check previous drawings and calculations from stress analysis. Assign new material property and conduct a stress test. Apply lubricant on the bearing to make it easier to rotate Cover the actuator with a bag to make Vacuum sealed Ziploc bag which can it waterproof. cover the actuator and try with demo. Mount the charger eye level to the user during the time of customer visit. Have the battery not operate if it is low on battery for user safety Amos look into ergonomics of the weight of the battery Bend the mounting bracket at the Brinkman Lab. Get vacuum powered suction cups from Seasuckers Richard run stress calculation and confirms material and surface area While meeting with customer slightly test by attaching the charger to the wall and see where the it may be positioned. The actuator will go back to its neutral position Have user have someone that could help once every 2 weeks to help with charging the battery Have the mounting bracket be bent back by the Brinkman lab and ensure it is straight. Testing suction cups forces by calculation and with demo Increase size of legs to 0.4" A36 Hot Rolled Steel Evaluating Solution PSP 6 Ziploc bag doesn t hold seal once a hole is placed for wiring. Bellows are now in consideration and will be tied off with a hose clamp. Neutral position of the actuator is when the seat is up and will not operate. Communicated with Theresa that the battery will need to be replaced by someone. Received approval of request. Mounting bracket was sent to the Brinkman lab where it was bent back to its original position. From calculation the suction cups do very well and can withstand a load from a 350 lb. person Device Legs buckling reduced and has a safety factor of which is in the 2-4 range Apply a water based lubricant on the After a week of letting the lubricant bearing to make it rotate easier. A Lubricant was applied to the bearings settle in the chair moves more freely sample lubricant was found in the on the light duty swivel now with less resistance. Plan to suction cup shipment that was meant have client test if it would need more. for bearings and is waterproof.

25 Problem Tracking 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 R1 R2 R3 Y4 Y5 G6 Suction cups not coming after order Finding bellows for our needs 13 Budget for BOM 14 Round bar not strong enough 15 Rollers lead time Drawings to water jet base plate New CAD drawing of final product 18 2 Clevises are too big Sales representative Find a new vendor not available and white Track down sales representative or suction cups sold out call Seasuckers Customizable bellows have to be bought in bulk Miscommunication on budget between team and administration. High costs due to stainless steel parts needed. 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 of the user the thickness of the original is too small Rollers from Motion Industries promised to come in by 11/7/14 but did not ship out until 11/11/14 Need rollers to help make drawings to place in the water jet machine Need to make drawing for seat and slide in Inventor With the height of the rollers and the height of the clevis base for 2 of them there is a mismatch in height between all the other clevises attached to the base. Call and see if instead of a bulk order a single order can be placed for the school Find cheaper alternative Propose a budget increase with reasoning Buy a bigger bar from Klein steel to replace the original bar. Try to expedite shipment or pick it up once it reaches the facility to reduce lead time Get drawings on the rollers to help with the drawing for the base. Contact vendors for their drawings to upload into the assembly Contact vendor and exchange the 2 clevises for smaller ones Use the clevis but increase the height of all the other clevises by using scrap material and attaching it from underneath Team get in contact with Seasucker and Chris from MSD office Search for another vendor that the bellow can be ordered from. Contact advisor and ask for a readjusted budget Contact Klein steel for the same bar but with a 3/4" diameter in exchange for the 1/2" diameter rod. Contact Chris Fisher to contact the supplier on how to speed the delivery process 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. Contact vendors for drawings and look for drawings online that look similar to the components purchased. 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. Contacted both Chris and Seasucker sale representative. Contacted McMaster Carr for a bellow and took the bellow to the machine shop where we used wire to tighten each side. Have advisor talk with Chris and Mark about budget for team to get more money Klein steel was contacted on (11/10/14) and we cannot exchange or return the original rod but purchase and pick up a new one. 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. Receive rails and carriages from McMaster Carr and updated water jet drawings. Called vendors and received no response or ability to not release drawings Vendor was contacted and new clevises were delivered. Evaluating Solution PSP 6 The suction came in. Delay in order due to sale representative being out for the week we wanted to place order. 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. Budget expanded to purchase more parts to finish prototype. 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. With the late delivery the meeting with Theresa had to be pushed back to next week Top and bottom plate were cut with water jet using scrap material for other uses. No response from vendors on the drawings and will have to make the drawings from scratch to best represent the final device. 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.

26 Problem Tracking Problem Number Identifying & Selecting Problem PSP 1 Meeting original customer deadline (11/13/14) Delivery of rails and carriages 21 Sitting height of the chair Analyzing Problem PSP 2 Generating Potential Solutions PSP 3 Selecting & Planning Solution PSP 4 Implementing Solution PSP 5 R1 R2 R3 Y4 Y5 G6 Parts are not in yet to finish assembly and Reschedule meeting with Theresa for Call Theresa and explain the situation human testing not another week. and reschedule conducted Having parts machined by the water jet. Unexpected machining needs 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. The chair sits too high when it is at it lowest position Water jet motor down. Clevises and pin ordered are not sustainable when submerged under water Contact PBC to return rails Purchase carriages from PBC Linear Purchase rails and carriages from another vendor Purchase low profile rails and cut corners of the base to reset suction cup placement therefore reducing the sitting height Wait for Water jet to be fixed Machine parts by milling Have the parts water jet outside of campus Machine parts from top and bottom plate cut outs Called PBC Linear and speak with a representative while looking at rails and carriages from other vendors. Purchased low profile rails and cut the corners of the base to reset suction cups Wait for the water jet to be fixed Design cut out from the top and bottom plate cut outs to machine and assemble Evaluating Solution PSP 6 Appointment was rescheduled to the Team has an extra a week to conduct next Thursday (11/13/14) and then testing and troubleshoot rescheduled again until further notice. Called PBC Linear and spoke with a representative. Rails could not be 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. 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. 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. 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. With the new carriages the clevis will have to be drilled instead of welded due to the material difference from cast iron to aluminum. Water jet was fixed. The clevises, bottom and top plate were cut to size.

27 Schedule Review

28 Schedule Review

29 Schedule Review

30 Review of Requirements Recommendations: Lower the overall weight of the device Use different materials Different position of the actuator Obtain appropriate actuator Be consistent with stakeholders and requirements Manufacture parts earlier Order parts earlier Logistics was major role in producing the bath tub lift. Parts that came late delayed the development of the device. Wood demo rather than PVC demo

31 Acknowledgements Art North John Bonzo Robert Kraynik Elizabeth Debartolo Jan Maneti David Hathaway Chris Fisher Matthew Marshall

32 Questions