**2. Background**

Users of wheelchairs continue to encounter some difficulties as they seek to navigate from one point to the other on rough terrain due to lack of stability when using rural off-road environment pathways [4]. Most existing wheelchairs are not suitable for use on extremely rough terrain thereby compromising the safety of the occupant [7]. Hence the objective of this chapter to design a wheelchair frame that offers optimum stability on rough terrain and does not readily overturn.

Effort to navigate extreme rugged pathways in a rural setting could be a challenge, such that even a great modern wheelchair may be found to be of limited usefulness [8]. What could be needed is an off-road design that is easy to manufacture and repair compared to designs done for a city environment where there are sidewalks. All terrain wheelchairs can increase the mobility range and access by taking occupant where one always wanted to go but were not able [9]. All terrain wheelchairs could be in various shapes and sizes, powered, manual and sometimes with a lever drive. Some have specific advantages such as the ability to maneuver on loose terrain covered by sand or gravel, in snow, over hilly terrain or on hills [10].

It is the unstable nature of existing wheelchair frames that demands for a wheelchair design modification to ensure increased increase stability on "non-ideal" terrain surfaces. Such rugged terrain may entail (but are not limited to): gravel, grass, dirt, and cracked asphalt or concrete. A wheelchair design modification is required for successful traversing of the adverse terrain while keeping four points of contact between the wheels and ground as well as maintaining the required stability

**159**

*Development of a Rough Terrain Wheelchair Design DOI: http://dx.doi.org/10.5772/intechopen.91267*

**3. Wheelchair literature review**

**3.1 Design and standards**

**3.2 General considerations**

well-being and convenience [15].

imposing difficulties to mobility.

occupant may get stuck in the process [16].

**3.3 Common wheelchair limitations**

and other low-income earners category can afford to buy.

and comfort for the operator [11]. It is the intention of this chapter to improve the current design within a reasonable cost range that most users within the rural area

The intended mandate is come with a design with improved performance that provides requisite seating and postural support without compromising strength, durability and safety [12]. The International Organization for Standardization (ISO) formulated international standards for wheelchair frames, the ISO 7176 series (1). The series specify the relevant terminology and testing processes to evaluate wheelchair parameters such as performance, size, strength, durability and safety. In some cases, the required conditions in the ISO 7176 series may not capture all typical requirements in less-resourced environment, as some of the requirements were meant to simulate the conditions in city environs with smooth tarred roads. It is therefore necessary to consider varied environments when formulating national standards, by looking at key parameters such as the weights and sizes of users, typical uses, and the available wheelchair designs and associated technologies within the country [13].

Wheelchair configuration should afford users to partake in whatever number life exercises as could be allowed. As a base prerequisite, a wheelchair ought to allow the operator to lead an increasingly dynamic existence without having any antagonistic impact on one's well-being or security. Solace and well-being comprise the two significant perspectives that influence the personal satisfaction of happy wheelchair users [14]. The well-being and security of operators ought not to be undermined so as to lessen costs during structure improvement. In spite of the fact that it might be contended that any wheelchair is superior to no wheelchair, this cannot be correct when the wheelchair turns into the reason of well-being dangers. It is in this respect a wheelchair ought to be intended to guarantee the client's improved great

The basic difficulties that a standard wheelchair faces involve challenges while crossing lopsided surfaces or negotiating hindrances in the pathway. Such problems may be the failure to continue any further when a wheel gets stuck in a downturn, with the end result that when the user endeavors to free oneself, the seat may get agitated and topples [7]. A comparative issue, with similar results, may happen when endeavoring to cross obstructions, for example, rocks, logs or curbs the pathway (**Figure 2**). A surface not smooth, covered with scrub and stones, may likewise be considered as uneven or unpredictable consequently

There are also cases where the user may be unable to generate enough sustained human power to climb steep grades. Thus, the conventional wheelchair has limited capability to traverse steep inclines [7]. The standard wheelchair typically uses narrow width pneumatic tires which can easily get punctured by branches, rocks and the like. When utilized in sandy, loose and unstable soil, the wheels sink and the

and comfort for the operator [11]. It is the intention of this chapter to improve the current design within a reasonable cost range that most users within the rural area and other low-income earners category can afford to buy.
