Conceptual design, development and fabrication of a prototype ergonomic lumbar support for motorcyclists

This study was conducted with the intention to investigate the need, design, develop,fabricate and testing a prototype of an ergonomic lumbar support for motorcyclists. The development process began with identifying the importance and the problems of existing motorcycles in the market. Motorcycle is the second common modes of transportation in Malaysia. As a relatively cheap and reliable mode of transportation, it is widely used by a large cross section of peoples. However, the current motorcycle design does not accommodate a back posture support and motorcyclists are more exposed to musculoskeletal disorders (such as low back pain). This study was undertaken in 5 stages (methods) in order to achieve its objective; survey on motorcyclists discomfort,anthropometric data collection, design, develop and fabricate the prototype using Pugh’s Total Design Process Model, Testing 1 (using Borg’s Scale) and Testing 2 (using Electromyography (EMG)) . The whole study was conducted in Polytechnic Sultan Azlan Shah, Perak, using the students (motorcyclists) as the sample. Their age ranges 18 to 24 years old. The results (survey) indicate that, majority (>50%) of the motorcyclists experienced discomfort in their body parts during the riding process. Higher discomfort rate was reported on the motorcyclist’s upper body parts (neck or head, shoulder, upper back, arms and hands, low back and buttocks) and correlated with their the riding posture. The critical design dimensions for the prototype (height, width, adjustable range and thickness) were obtained from the anthropometric dimensions of motorcyclists a were used in the design process. The subjective method results highlight that the rate of discomfort level (in all body parts) decreased over time during the testing period with the prototype (lumbar support). In terms of the discomfort ‘break point’, the motorcyclists identified low back and upper back as the most affected body parts prior to comfort changes during the testing period with the use of the prototype. Meanwhile, the electromyography results show a reduction of muscle activity in the lumbar region in term of the average EMG values, maximal voluntary contraction (%MVC) of EMG activities at the 10th, 50th and 90th percentile and EMG change over time (mean % change per measurement period). Overall, the use of prototype provides a protective mechanism (provides postural stability and integrity) for the motorcyclist’s musculoskeletal system, particularly the spinal column (from exposures to intensity, duration and frequency of physical risk factors which contribute to the low back pain). Therefore, this prototype is capable of providing ideal posture while simultaneously enhancing the comfortability (reduce discomfort) of the motorcyclist during the riding process. However, further evaluation on the prototype needs to be conducted to determine their stability, solidity, durability and safety over prolonged use.