{"id":25928,"key":"Wheelchair_Maintenance","title":"Wheelchair Maintenance","latest":{"id":1223387,"timestamp":"2026-01-08T22:32:09Z"},"content_model":"wikitext","license":{"url":"https://www.appropedia.org/Appropedia:Copyrights","title":"CC-BY-SA-4.0"},"source":"[[File:Wheelchair-Brake.jpg|thumb]]\n\n{{Project data\n| authors = User:5aljh\n| status = Designed\n| type = Wheelchair\n| location = Kingston, Canada\n}}\n\nIn many areas of the developing world the conditions under which [https://en.wikipedia.org/wiki/Wheelchair wheelchairs] are used are significantly rough and damaging to the equipment. While companies such as [http://www.whirlwindwheelchair.org/ Whirlwind] and [http://www.nextmobilitynow.com/ Next Mobility] have adapted wheelchair design to be more suitable for extreme terrain, the access to these wheelchairs is limited. Many of the disabled are accommodated with manual wheelchairs that have been donated from hospitals and, in most cases, are ill fitting.\n\nStudies conducted in [https://en.wikipedia.org/wiki/El_Salvador El Salvador], with wheelchair users and technicians, illuminated common problems affecting ideal wheelchair function and user comfort. This project has used this feedback in designing a maintenance and repair kit that gives [https://web.archive.org/web/20120614235751/http://wheelchair.ca:80/manualcomp.php manual wheelchair] users and technicians the ability to perform repairs and adjustments as necessary.\n\n== Problem definition ==\n\nThe main objective of this [[Mech425 AT Project]] was taken from a trip report compiled by Lisa Catana after visiting wheelchair users in El Salvador. The report outlined the need to develop a maintenance and repair kit that includes basic tools for repair, lubrication and low cost seating construction with easily accessible materials such that wheelchairs users and technicians can properly maintain and repair wheelchairs, preventing damages and extending the life of the wheelchair.<ref name=\"lisa\">Cantana, L. \"Project Acesso Trip Report November 21 - December 1, 2006\"</ref>\n\n== Background ==\n\n[http://www.whirlwindwheelchair.org/ Whirlwind] has developed wheelchair technology to improve the lives of the many persons worldwide living with physical disabilities. The highly publicized [https://web.archive.org/web/20110426055429/http://whirlwindwheelchair.org:80/wwi/pages/roughrider.html roughrider wheelchair]as shown in figure 1 has added features that compensate for discomfort due to vibrations and others that increase mobility in and around uneven surfaces.<ref>Whirlwind Wheelchair International, RoughRider, [https://web.archive.org/web/20110426055429/http://whirlwindwheelchair.org:80/wwi/pages/roughrider.html http://web.archive.org/web/20110426055429/http://whirlwindwheelchair.org:80/wwi/pages/roughrider.html], Accessed March 23, 2010</ref>\n\n[[File:Wheelchair 1.JPG]]\n\n'''Figure 1: Showing the Whirlwind Wheelchair; RoughRider, specifically designed to weather rougher terrains'''\n\nDespite the best efforts of whirlwind, roughrider wheelchairs cannot be made accessible to all those in need and instead, wheelchairs show in figure 2 are more likely to be found in developing countries.\n\n[[File:Wheelchair basic 1.JPG]]\n\n'''Figure 2: Showing the more likely wheelchair used'''\n\nThe harsh terrain, lack of wheelchair accessible buildings and humid climate mean that wheelchair users are pushing the physical limits of their chairs. Furthermore the widespread use of basic wheelchairs, which lack ergonomic features, result in the general discomfort of the user. The more frequent failures that can be addressed from a maintenance and repair kit involve the functionality of the brake and tires as well as issues of lubrication and adjustable seating options.<ref name=\"lisa\" />\n\n== Wheelchair Brakes ==\n\nThe [https://web.archive.org/web/20120406061939/http://wheelchair.ca:80/manualbrakes.php braking system of wheelchairs] is unlike that of a bicycle, whereby the brakes are used to lock the chair in position rather than slow its motion. Many wheelchair brakes are similar to that shown in figure 3, such that pulling a lever initiates contact between the brake and the tire with enough pressure to inhibit motion.<ref>Wheelchair.ca Medical Equipment Information & Resources, \"Wheelchair Brakes\", [https://web.archive.org/web/20120406061939/http://wheelchair.ca:80/manualbrakes.php http://web.archive.org/web/20120406061939/http://wheelchair.ca:80/manualbrakes.php], Accessed March 24, 2010</ref>\n\n[[File:Wheelchair-Brake.jpg]]\n\n'''Figure 3: Showing one example of brakes found on a wheelchair'''\n\nThe cause of failure could be speculated to be due to material failure, rust, improper use of device, etc, but in this case is unknown and is likely to vary from one user to another.\n\n== Tires ==\n\nThere are two types of [https://en.wikipedia.org/wiki/Tire tires] for manual wheelchairs; [https://en.wikipedia.org/wiki/Pneumatic pneumatic] and solid both of which have their own advantages and disadvantages. Pneumatic tires, like those found on bicycles have air filled tubes. These tires provide a smooth ride, absorbing shocks from uneven surfaces but are more likely to be damaged by rough and sharp objects. Issues of leaking can arise from poor sealing, small punctures and malfunctioning nozzles.<ref name=\"Wheelchair tire tips\">SpinLife.com Experts in Motion \"Wheelchair Tire Tips\" http://www.spinlife.com/spintips/details/k/Wheelchair%20Tire%20Tips/a/327/c/3, Accessed March 25, 2010</ref>\n\nOperating the wheelchair with poorly inflated or flat tires can have destructive effects on the rim of the wheel. Correctly inflated tires will prevent [https://web.archive.org/web/20170820105208/http://mountainbike.about.com:80/od/mountainbikeglossary/g/Pinch_Flat.htm pinch flats].<ref>Brown, S. \"Bicycle Tires and Tubes\" [https://www.sheldonbrown.com/tires.html http://www.sheldonbrown.com/tires.html] Acessed March 29, 2010</ref>\n\nSolid rubber tires, are well solid, and therefore have no issues with punctures. However are less comfortable as the user feels the effects of every bump and uneven surface along their path.<ref name=\"Wheelchair tire tips\" />\n\n== Lubrication ==\n\nAs with any other moving [https://web.archive.org/web/20160611001541/http://www.flying-pig.co.uk:80/mechanisms mechanism], joints and junctures need to be [https://en.wikipedia.org/wiki/Lubrication lubricated] for optimum performance.<ref>Esteban, J. Importance of Lubrication http://quazen.com/recreation/autos/the-importance-of-lubrication/ Accessed April 16, 2010</ref> This is the case with all wheelchairs where lubricants are used to reduce wear and prolong the use of the device. Dry lubricants are more user friendly and are most compatible with wheelchair materials, although wet lubricants are still appropriate.<ref name=\"lube\">Denison, I., 2006 \"Wheelchair Maintenance Series: Lubrication\", G.F. Strong Rehab Centre</ref>\n\nSimilar to over inflation of tires, it is important not to over lubricate parts as the excess grease binds dirt and other particles that will prevent proper function.<ref name=\"lube\" />\n\n== Seating Adjustments ==\n\nIdeally wheelchairs would be customized for each user so that their arm rests, foot rests, and angle of inclination and position of wheels would compliment their desired posture while sitting in their wheelchair. This is not the case with those buying new wheelchairs, much less those using secondhand chairs.\n\nOne adjustment that can be made is providing appropriate cushions for the wheelchair. Due to the significant amount of time spent in the wheelchairs, failure to do so results not only in discomfort of the user but can cause the development of sores and ulcers which can worsen the physical condition of the user and in extreme cases causes death.<ref>Krizack, M. \"It's Not About Wheelchairs\" [https://web.archive.org/web/20110728175435/http://www.whirlwindwheelchair.org/articles/current/article_c02.htm http://web.archive.org/web/20110728175435/http://www.whirlwindwheelchair.org/articles/current/article_c02.htm] Accessed April 2, 2010</ref>\n\n== User Manual ==\n\nThe purpose of having a wheelchair user manual is to provide an added resource for the user. While every wheelchair manufacturer has a manual for each of its chairs, the target user in this study is using a second hand chair/ refurbished chair and is unlikely to possess the manual. Many of the users want to know how to maintain and repair the chairs themselves so by giving them this kind of resource allows them to understand the function of the major components of the wheelchair, easily recognize problems and suggested maintenance and damage mitigation.\n\nFrom the trip report it was observed that most wheelchairs were made by [http://www.invacare.com/cgi-bin/imhqprd/index.jsp Invacare] however, [http://www.thewheelchairsite.com/wheelchair-manufacturers.aspx other manufactures] include [http://www.pridemobility.com/ Pride Mobility], [https://web.archive.org/web/20120304093609/http://www.sunrisemedical.ca/index.jsp Sunrise Medical], [http://www.colourswheelchair.com/ Colours in Motion] and [http://www.quickie-wheelchairs.com/ Quickie Wheelchairs].\n\nHere are links to a couple wheelchair user manuals from different manufactures.\n\n[[File:Eclipse wheelchair manual.pdf|1035x1035px]]\n\n[[File:Esteem wheelchair manual.pdf|1132x1132px]]\n\n[[File:Excel wheelchair manual.pdf|1035x1035px]]\n\n[[File:Invacare wheelchair manual.pdf|800x800px]]\n\n[[File:Pride manual.pdf|1035x1035px]]\n\n== Maintenance and Repair Kits ==\n\nEach problem area has been assessed and tools necessary to fix the problems have been identified. Furthermore a design for an alternative brake system and tools and materials necessary to build this break have also been identified. All these tools and materials have been recommended to be included in a maintenance and repair kit for wheelchair users and technicians, specifically, in El Salvador. The kit itself can be customized based on price, size and weight constraints. To do so open the spreadsheet in the 'Final Kit' section below, selecting product combinations and viewing the size, price and weight on the kit.\n\nBelow is a more detailed description of the materials and tools included, instructions as to how to use some of the components as well as alternative materials that can be used in the place of those suggested.\n\n== Basic Tools ==\n\nTwo basic tools for repair are an [http://blogs.toolbarn.com/mattg/uploaded_images/rapidslide-wrench-748854.jpg adjustable wrench] and [http://thisoldhouse.typepad.com/.a/6a00d8341cae1553ef0128758971c2970c-450wi multi tip screw driver]. These are essential in all aspects of maintenance; checking [http://www.globalfastenermarket.com/upload/1006/image/Bolts5-4-07.jpg bolts] and [https://web.archive.org/web/20070306023602/http://www.engineeredpartsinc.com:80/images/nuts_lock_lg.jpg nuts], adjusting leg rests, footrests, armrests and backrests, adjusting [http://www.familycar.com/alignment.htm wheel alignment] as well as changing tires or removing the wheel.<ref>SpinLife.com Experts in Motion \"Manual Wheelchair Maintenance\" http://www.spinlife.com/spintips/details/k/manualwheelchairmaintenance/a/116/c/2 Accessed March 19, 2010</ref>\n\n[http://www.spinlife.com/spintips/details/k/manualwheelchairmaintenance/a/116/c/2 A Suggested Manual Wheelchair Maintenance Guide] outlines the types of maintenance checks that should be performed on a daily, weekly, monthly and annual basis.\n\n== Brake Design ==\n\nAn alternative brake system was designed to replace existing brakes broken beyond repair.<ref name=\"lisa\" />The brake design compensates for limited access to materials and resources and was conceived using a simple approach.\n\nThe basic concept behind this design is that the brake is enabled by sliding two pins along a slot until the brake arm locks into place while simultaneously making contact with the tire and preventing rotation of the wheel. The braking system comprises of 3 components; the brake arm, the slotted base and an attachment device to the frame of the wheelchair.\n\nThe brake arm, as shown in figure 4, consists of a lever, 2 pins of varying diameters and the brake material (not included in diagram) which is to be attached to the base of the arm.\n\n[[File:Slottedbase new.JPG]]\n\n'''Figure 4:Brake arm (left) and slotted base (right)'''\n\nThe base contains a slot along which brake arm slides, as illustrated in figure 4 above. The pins are constrained within the slot by a stopper. The stopper allows for horizontal and vertical movement of the arm along the plane of the base while preventing the arm moving perpendicularly to the base.\n\nA simple representation of how the brake arm and slotted base interact with each other when the brake is initiated is shown in figure 5 below.\n\n<gallery>\nImage:Position 5.JPG|a\nImage:Position 4.JPG|b\nImage:Position 3.JPG|c\nImage:Position 2.JPG|d\nImage:Position 1.JPG|e\n</gallery>\n\n'''Figure 5: Illustration of brake as it moves from the off to on position'''\n\nDuring normal use of the wheelchair the brake remains in the 'off' position as shown in image (a) of figure 5 above. To initiate the brake the user lifts and rotates the arm through positions shown in images (b), (c) and (d), allowing the pins to follow the slot. Finally with the the arm in position shown in image (e), the brake is then in contact with the tire and rotation of the wheel is prevented.\n\nThe brake can be made from any strong, rigid material. Using a wooden base would allow for easy cutting of the slot and metal nails as pins would provide for smooth sliding along slot while ensuring the stability of the device.\n\nThe material used to inhibit motion of the wheel, that is the brake material, must have a high coefficient of friction when in contact with the wheel, be resistant to wear and environmental effects.<ref>RoyMech \"Clutch/ Brake Material Properties\" [https://web.archive.org/web/20190620181917/http://www.roymech.co.uk:80/Useful_Tables/Drive/Brake_Clutch_mat.html http://web.archive.org/web/20190620181917/http://www.roymech.co.uk:80/Useful_Tables/Drive/Brake_Clutch_mat.html] Accessed April 18, 2010</ref> Rubber, old tires, brake pads from old cars or bicycles or a dense, rough plastic material are all appropriate materials for this application. When attaching the material to the arm, a point to consider is the shape of the material. Figure 6 below shows two options with diagram a showing the more preferable shape.\n\n[[File:Matrerial shape.JPG]]\n\n'''Figure 6: Showing the shape options for the brake material when attached to brake arm'''\n\nNo prototype was done and hence no testing of this design has been performed, however, figure 7 below shows the suggested dimensions for the brake arm and base.\n\n<gallery>\nImage:Dimensioned arm.JPG|Fig a: Brake Arm with Dimensions\nImage:Dimensioned base.JPG|Fig b: Brake Base with Dimensions\n</gallery>\n\n'''Figure 7: Showing a dimensioned drawing of the brake arm and base'''\n\nThe brake material is to be attached to the arm. The length of this attachment will vary depending on the location of the brake base on the wheelchair frame. Similarly, the length of the lever can be adjusted to suit the user.\n\nWhile the ratio of diameters for the large and small pins is 1:2, this need not be the case. Any two pins of differing diameters can be used, once the slot has been adjusted (with appropriate tolerances) to accommodate the diameters, such that the larger pin is constrained to only move vertically.\n\nFor simplicity of producing this design on varying scales, Pythagorean numbers were used when dimensioning the slot on the base.\n\nThe placement of the brake is intended for a horizontal bar on the frame of the wheelchair, below the seat (shown by the red box in figure 8 below). The following suggestions can be used as an attachment device: clamp or permanent attachment to the frame using screws. The clamp is likely to be the more reasonable option as adjustments can be made more easily and will not compromise the structural integrity of the frame.\n\n[[File:Location of brake.JPG]]\n\n'''Figure 8: Showing the intended location for the brake described above'''\n\n== Tire Repair ==\n\nThe main issue with inflatable tires is leaking and hence deflation.<ref name=\"lisa\" />The use of the wheelchair on unpaved, uneven surfaces increases the chance of punctures and small holes developing. Patching tires will fix holes and therefore reduce the frequency that the user needs to re-inflate their tires.\n\nThe basic components for tire repair, patches and glue, have been included in this kit. Due to the adhesives necessary to patch tires it is unlikely that there is a natural substitute that can be used in its place. The number of patches in the kit should be adequate and should all be used then the wheels of the chair should be replaced all together.\n\nUnder the likely circumstances where replacing faulty wheels is not an option, the alternative is to [http://www.spinlife.com/spintips/details/k/Wheelchair%20Tire%20Tips/a/327/c/3 remove and replace] the air tube with solid materials. Ideally this solid material would be rubber however here a some suggestions for other materials:\n\n* Foam; firm foam would help absorb shocks from bumps and uneven surfaces. It would have to be densely packed into the tire so that when loaded the wheelchair is not rolling on its rims.\n* Coconut husks; it would also have to be densely packed to prevent damage to the rims. Special attention would be necessary to ensure evenly packing husks around entire wheel.\n\nOne way to ensure that damages are minimized is maintain [https://www.sheldonbrown.com/tires.html properly inflated tires] at all times.\n\n== Seating/ cushioning ==\n\nThe option for seat cushioning for the kit is to either include a sizable piece of foam that can further be cut or re-sized by the user, to better suit the user. A standard wheelchair has a seat depth of 16\" and a seat width of 16 \", 18\" or 20\".<ref>Wheelchair.ca \"Standard Wheelchairs\" [https://web.archive.org/web/20111221041948/http://wheelchair.ca:80/standard.php http://web.archive.org/web/20111221041948/http://wheelchair.ca:80/standard.php] Accessed March 24, 2010</ref> The cut of foam included in the kit can be specified in the spreadsheet below. The thickness should depend on the firmness of the foam where for a firm grade, a thinner thickness can be used. Generally, the type of foam used and the manner in which it is cut depends on the user's comfort.\n\nDue to the variability in the size of each wheelchair cushion, a case for the cushion was not considered for the kit. Instead, suggestions for casing include cloth found in the house; towels, sheets, t-shirts.<ref>Disability India Network \"Cushion Design for Wheelchair Competition\" Accessed April 2, 2010</ref>\n\nFor additional designs for seating cushions made from low cost, locally accessible materials, [http://resna.org/ RESNA] has received many [low-cost seating designs], within those constraints, from inventors around the world.\n\n== Lubrication ==\n\nThere are several options for lubricating the wheelchair; wet and dry lubricants and vegetable oils. The advantages of using generic lubricants are that there are variations of lubricants for many specific applications and therefore the most appropriate, cost effective lubricant has thus been included into the kit. There is always the option of not including it in the kit and the other alternatives can also be appropriate.\n\nVegetable oils have become popular with those looking for natural and easily accessible lubricants. Their properties include good [https://www.answers.com/topic/shear-resistance resistance to shear], high [https://en.wikipedia.org/wiki/Flash_point flash point] and high [http://www.tpub.com/content/engine/14105/css/14105_37.htm viscosity index]. Caster oil is one such vegetable whose viscous nature and thermal properties, where it is unlikely to dry or harden under the conditions of use, make it a good lubricant for wheelchair applications. Industrial caster oil is the best choice however, household caster oil found in pharmacies can also be used.<ref>Amateur Work Magazine Vol5, Miscellaneous Authors \"Caster Oil As A Lubricant\" http://chestofbooks.com/crafts/popular-mechanics/Amateur-Work-5/Castor-Oil-As-A-Lubricant.html Accessed April 6, 2010</ref>\n\nSome cooking oils can be used as viable options.<ref>Garret, S. \"Vegetable Oil For Lubricating Chain Saws\" http://www.fs.fed.us/t-d/pubs/html/98511316/98511316.html Accessed April 6, 2010</ref> While they are more expensive than industrial oils or lubricants, they are more likely to be found within the house than the other two options.\n\n== The Final Maintenance and Repair Kit ==\n\nThe potential maintenance and repair kit to be distributed to wheelchair users in El Salvador, and from there, anywhere else in the world, has been presented in the form of a spreadsheet. The spreadsheet allows users to customize the kits and include or exclude unncessary tools or materials and thus choose an appropriate kit based on size, weight or price constraints. Factors affecting the decisions made, especially with respect to product selection, has been included in the spreadsheet and will be elaborated on further in this article.\n\nThe spreadsheet can be downloaded using the following [http://drop.io/993egun# link]. Please see notes in the discussion tab regarding the downloading of different versions of this spreadsheet.\n\n== Limitations and Recommendations ==\n\nThe most significant limitation of the design and construction of this kit is that it has been constructed using materials and tools found and priced within Canada. This presents a couple problems. Firstly is the affordability of the kit. Especially when converted into the [https://en.wikipedia.org/wiki/Salvadoran_col%C3%B3n El Salvador Colon] it is clear that even the most basic kit will be out of the price range of many of the wheelchair users most in need of it.\n\nSecondly, if considering the given maintenance kit as a guideline for tools and materials, which are to be sourced locally, then the economic analysis performed is a poor representation of the actual cost of the kit. How much a kit that has been assembled in El Salvador would be is unknown. Furthermore, the question of access to and availability of the same/ similar materials and tools included in the Canadian assembled kit poses itself. With regards especially to using low cost, easily accessible materials in El Salvador, there is no doubt that all maintenance can be performed using local materials. However, being unaware of what materials are accessible it has been difficult to suggest with confidence specific materials.\n\nDespite these limitations, the kit design and this article itself provides many resources for not only wheelchair maintenance and repair but also ways to ensure that damage is prevented. For the most part, the design of the brake was done as simply as possible and intended to be made from low cost, locally available materials. If nothing else, users should be able to gain a good understanding of what tools and materials are necessary to address their major issues.\n\nFurther work on the maintenance kit should dive further into the different, appropriate resources available, the cost of such resources and perform a price comparison to determine if a kit assembled in El Salvador is indeed cheaper.\n\nWith regard to the brake design, more time needs to be extended to test it and make appropriate adjustments.\n\nAnother limitation of this article is that it has been prepared for an English speaking audience. All instructions and user manuals would need to be translated, or found in Spanish print, to be understood by the users in El Salvador.\n\nOne of the major problems is that there are some problems cannot be fixed. If the wheelchair is too small then other problems will be inherent; chronic discomfort and excessive pressure on the frame and wheels of wheelchair causing structural damage. Even the most elaborate kit will not be able to keep that wheelchair in good, working condition. It might be insulting to suggest proper diet and exercise to the users but doing so would ensure that the wheelchair does not endure unnecessary stresses and strains throughout its daily use. Proper day to day use of the device is the best way to maintain the device.\n\n== Summary ==\n\nA maintenance and repair kit was developed based on an analysis of issues associated with faulty tires, inappropriate or uncomfortable seating conditions, lubrication the wheelchair and a functionality of the brake system. The kit was designed to include all tools, materials and instructions necessary to address all of these problem areas. Furthermore the kit can be customized to include or exclude tools due to constraints on size, weight or price. Alternative materials, to those suggested for the kit, have been discussed should the user decide to build their own maintenance and repair kit themselves.\n\n== References ==\n\n<references />\n\n{{Page data\n| license = CC-BY-SA-3.0\n| part-of = Mech425\n| organizations = Queen's University\n| keywords = Wheelchairs, transport, mobility and rehabilitation, Appropriate technology\n| sdg = SDG10 Reduced inequalities\n| description = Wheelchair care extends mobility life. Appropedia explains cleaning, repairs, and adjustments for comfort and durability.\n}}\n\n[[Category:Wheelchairs]]\n[[Category:Transport]]\n[[Category:Mobility and rehabilitation]]\n[[Category:Appropriate technology]]"}