Proceedings 19 th Triennial Congress of the IEA, Melbourne 9-14 August 2015 1 A Study on Motorcycle Usage and Comfort in Urban India Sai Praveen Velagapudi a,b , Ray G. G b a Research & Development, TVS Motor Company, INDIA; b Industrial Design Centre, IIT Bombay, Mumbai, Maharashtra, INDIA Motorcycle is one of the major modes of personnel transport in developing countries. The usage of motorcycles is often in dense traffic and bad roads which causes repetitive loading on the musculoskeletal system of the rider. The design of motorcycles needs careful consideration of ergonomics and human factors to avoid injuries to the musculoskeletal system due to this repetitive loading and to ensure comfort of the user. However there is very little research on the design ergonomics of motorcycles, especially considering the usage patterns. This is a preliminary study aimed at understanding the usage patterns and discomfort of motorcycle users in India and thereby establish a base for further research on motorcycle ergonomics. The study has been carried out through a questionnaire based survey. The questionnaire had three sections, the first to understand usage patterns, the second to understand the importance of comfort as a factor when buying a motorcycle and the third section to understand physical discomfort due to the use of motorcycle. A new rating system was developed for the third section of the questionnaire based on the body part discomfort scale and the RBG pain scale. The questionnaire was self-explanatory and was designed to be filled without supervision. The study was conducted across five cities in India and a total of 221 subjects volunteered to participate in the study. The results of the study confirm the common understanding that all two wheelers in India, irrespective of their segment, are frequently used for commuting to work. The results also show that motorcycles are predominantly used for doing house hold activities. Further the results show that comfort is one of the top three considerations when buying a motorcycle in India and therefore should be an important consideration in design. The results of the discomfort survey show that majority of users perceive discomfort in parts of their upper body especially the neck, back, buttocks, wrists and shoulder. Low back and buttocks are the critical areas, where the discomfort perceived is significantly higher than the other areas of the body (p two tailed < 0.05, paired t test). More than 25% of the users reported severe discomfort in low back and buttocks that needed intervention for relief. The results of this study emphasize the need and highlight the scope of research on motorcycle ergonomics. Note: The word motorcycle in this text refers to all powered two wheelers. Keywords: Motorcycle Ergonomics, Usage patterns, User study, Body Part Discomfort, Design 1. Introduction Motorcycles are a quick and easy means of transport in modern cities. They are economical, offer better fuel efficiency and a faster commute compared to other modes of transport. These benefits have helped motorcycles become a major mode of transport especially in developing nations. Motorcycles, like any other automobile, need to accommodate people of different dimensions in a constrained space. However apart from typical controls like throttle, brake clutch, etc., motorcycle riding also involves maintaining the balance of the vehicle (at slow speeds) which requires continuous adjustments of the steering and upper body position (Either, 2000). The use of motorcycles in dense traffic (at low speeds) therefore causes high repetitive loading on the musculoskeletal system of the rider and can lead to repetitive strain injuries. In order to avoid such injuries and ensure comfort to the user, design of motorcycles needs careful consideration of ergonomics and human factors. However there is very little research in this area to support design of motorcycles, as a result the motorcycle design relies heavily on making physical prototypes and testing using expert riders in an iterative way. This method is expensive and does not guarantee good results. There is a need for research on motorcycle ergonomics to enhance the design of motorcycles based on scientific data.
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Proceedings 19th Triennial Congress of the IEA, Melbourne 9-14 August 2015
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A Study on Motorcycle Usage and Comfort in Urban India
Sai Praveen Velagapudia,b, Ray G. Gb
aResearch & Development, TVS Motor Company, INDIA; bIndustrial Design Centre, IIT Bombay, Mumbai, Maharashtra, INDIA
Motorcycle is one of the major modes of personnel transport in developing countries. The usage of motorcycles is often in dense traffic and bad roads which causes repetitive loading on the musculoskeletal system of the rider. The design of motorcycles needs careful consideration of ergonomics and human factors to avoid injuries to the musculoskeletal system due to this repetitive loading and to ensure comfort of the user. However there is very little research on the design ergonomics of motorcycles, especially considering the usage patterns. This is a preliminary study aimed at understanding the usage patterns and discomfort of motorcycle users in India and thereby establish a base for further research on motorcycle ergonomics. The study has been carried out through a questionnaire based survey. The questionnaire had three sections, the first to understand usage patterns, the second to understand the importance of comfort as a factor when buying a motorcycle and the third section to understand physical discomfort due to the use of motorcycle. A new rating system was developed for the third section of the questionnaire based on the body part discomfort scale and the RBG pain scale. The questionnaire was self-explanatory and was designed to be filled without supervision. The study was conducted across five cities in India and a total of 221 subjects volunteered to participate in the study. The results of the study confirm the common understanding that all two wheelers in India, irrespective of their segment, are frequently used for commuting to work. The results also show that motorcycles are predominantly used for doing house hold activities. Further the results show that comfort is one of the top three considerations when buying a motorcycle in India and therefore should be an important consideration in design. The results of the discomfort survey show that majority of users perceive discomfort in parts of their upper body especially the neck, back, buttocks, wrists and shoulder. Low back and buttocks are the critical areas, where the discomfort perceived is significantly higher than the other areas of the body (p two tailed < 0.05, paired t test). More than 25% of the users reported severe discomfort in low back and buttocks that needed intervention for relief. The results of this study emphasize the need and highlight the scope of research on motorcycle ergonomics.
Note: The word motorcycle in this text refers to all powered two wheelers.
Keywords: Motorcycle Ergonomics, Usage patterns, User study, Body Part Discomfort, Design
1. Introduction Motorcycles are a quick and easy means of transport in modern cities. They are economical, offer better fuel efficiency and a faster commute compared to other modes of transport. These benefits have helped motorcycles become a major mode of transport especially in developing nations. Motorcycles, like any other automobile, need to accommodate people of different dimensions in a constrained space. However apart from typical controls like throttle, brake clutch, etc., motorcycle riding also involves maintaining the balance of the vehicle (at slow speeds) which requires continuous adjustments of the steering and upper body position (Either, 2000). The use of motorcycles in dense traffic (at low speeds) therefore causes high repetitive loading on the musculoskeletal system of the rider and can lead to repetitive strain injuries. In order to avoid such injuries and ensure comfort to the user, design of motorcycles needs careful consideration of ergonomics and human factors. However there is very little research in this area to support design of motorcycles, as a result the motorcycle design relies heavily on making physical prototypes and testing using expert riders in an iterative way. This method is expensive and does not guarantee good results. There is a need for research on motorcycle ergonomics to enhance the design of motorcycles based on scientific data.
Proceedings 19th Triennial Congress of the IEA, Melbourne 9-14 August 2015
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This requires a detailed understanding of the usage patterns and the discomforts of users with current motorcycles.
Robertson (1985) conducted a study to understand the usage patterns and discomfort among motorcycle riders in the United Kingdom. A total of 121 riders participated in the study. The results suggested that motorcycle riders often suffered discomfort and that the level of discomfort varied among different segments of motorcycles and different parts of the body. Karmegam (2009) conducted a study in Malaysia with 957 students from the Polytechnic of Sultan Azlan Shah to analyse discomfort among motorcycle users. The results showed that riders experienced discomfort mainly in the upper body parts and there are differences in the areas where males and females perceived discomfort. However there are very few such studies in India to understand the usage patterns and discomfort of motorcycle users in a comprehensive manner.
India is one of the largest motorcycle markets in the world with annual sales of more than ten million vehicles. There are three major segments of motorcycles in India, the economy segment, premium segment and the gearless (CVT) step through segment. Table 1 gives the typical specifications of each segment and figure 1 shows typical products in each of the segment.
Table 1: Typical specifications of the three major segments of motorcycles in India
Economy Premium Gearless Step through)
Engine Capacity (cm3) 100-125 > 150 90-125 Posture Upright Leaning forward Upright Top Speeds (kmph) 100 >120 90 Power (bhp) 9 to 12 >14 7 to 10
(a) (b) (c) Figure 1: Typical product in (a) Economy Segment, (b) Premium Segment, (c) Gearless Step through Segment This study is aimed at understanding the usage patterns and estimate the discomfort due to motorcycle usage across different segments of motorcycles in India and thereby provide a basis for further research by identifying the key areas in motorcycle ergonomics.
2. Method The study was conducted using a questionnaire based survey. The survey was carried out across five cities in India, Hosur, Bangalore, Hyderabad, Trivandrum and Mumbai. The study was restricted to males and a total of two hundred and twenty one motorcycle users volunteered to participate in the study. The questionnaire had three sections and was designed to be filled without supervision. The first section had questions to identify the usage patterns where the user was asked to fill in the frequency of using their motorcycle for various purposes and in different road conditions, figure 2 shows some of the questions in this section.
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Figure 2: Section 1 of the survey, usage patterns.
The second section needed the user to rank the considerations when buying a motorcycle. Various considerations like mileage, cost, comfort, brand, etc. were listed, figure 3 shows the details.
Figure 3: Section 2 of the survey, Considerations while buying a motorcycle.
The third section needed the user to rate the discomfort perceived in various parts of his body because of riding motorcycle. A rating scale for discomfort was developed for this section of the questionnaire. It used an image that represents the typical riding posture on a motorcycle to identify the various body parts pictorially as used in the body part discomfort scale (Corlett 1976). Further a modified form of RBG pain
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scale (Venkatesh 2006) was used to rate the level of discomfort in each part of the body, figure 2 shows the details of the rating scale.
Figure 4: Rating scale used for quantifying discomfort. 3. Results A total of 221 male motorcycle users volunteered for this study, a physical copy of the questionnaire was mailed to all of them. About 24 of the volunteers did not return the questionnaires back in time while another 19 did not completely fill the questionnaires. The remaining 178 valid responses were compiled using Microsoft Excel for further analysis. Table 2 gives the general statists of the 178 volunteers in comparison with the Indian population as reported by the Size India project (Dileep Kulkarni 2011) and table 3 gives a comparison on the general statistics between users of the three segments of motorcycles.
Table 2: General Statistics of the Study sample This Study (n= 178) Size India Age Height Weight Height Weight Mean 30.7 173 73.3 167.3 64 SD 6.6 8.89 11.3 6.8 12.4 5P 23 158 56 156.3 45.7 50P 29 173 72.5 167.5 63.0 95P 44.2 183 90 178.7 85.4
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Table 3: General Statistics of study sample segment wise Economy (n=74) Premium (n=66) Gearless Step Through
(n=38) Age Height Weight Age Height Weight Age Height Weight
3.1 Usage patterns The average monthly usage of motorcycles was reported as about 610 kms. Over 75% of the users reported to use the motorcycle at least once a day and only 32% of the users reported to travel with a pillion frequently. Table 4 gives the statistical details of daily usage segment wise. Table 4: Average Monthly Usage, segment wise
Economy Premium Gearless Step Through
Mean Usage(kms) 684.6 627.0 363.4
Standard Deviation 455.1 434.5 287.1
Further the users were asked how frequently they used their motorcycle for three different purposes,
travel to work, household activities and long rides/leisure. Figure 5 shows the percentage of users who reported using their motorcycle “frequently” or “always” for each of the purpose (Refer figure 2 for the question) and figure 6 shows the same results segment wise. Table 5 gives the overall distribution of responses to this question.
Figure 5: Percentage of users reporting frequent usage of motorcycle for a given purpose.
Figure 6: Comparison of usage patterns between different segments.
62% 69%
24%
0%
20%
40%
60%
80%
Travel to work House hold activities Long rides/Liesure
Frequent Motorcycle Usage
66% 61%
22%
68% 70%
35% 42%
79%
8%
0%
20%
40%
60%
80%
100%
Travel to work House hold work Long rides
Frequent Motorcycle Usage Economy Premium Gearless Step Through
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Table 5: Motorcycle usage patterns in urban India. Travel to work House hold work Long rides
Never 18 1 58
Sometimes 49 55 77
Frequently 33 62 21
Always 78 60 22
Total 178 178 178
3.2 Considerations when buying a motorcycle In the second part of the questionnaire the users were asked to rank the various factors that they considered important when buying a motorcycle, the factors included eight factors derived from interviews with motorcycle customers, space was provided in the survey sheet for users to add and rank any further factors that were not mentioned (refer figure 3). About 90% users ranked the given eight factors while 10% added more factors. The factors added commonly were “Engine Noise/Vibration” and “Safety”. Figure 7 shows the percentage of users who ranked a given factor in the top three considerations when buying a motorcycle and table6 gives a comparison of the same result segment wise.
Figure 7: Percentage of users ranking a given factor in the top three consideration when buying a motorcycle.
Table 6: Percentage of users ranking a given factor in the top three when buying a motorcycle, segment wise.
3.3 Discomfort due to use of motorcycles The results of the discomfort survey showed that more than 95% of the users perceive discomfort in some or the other body part. 87% of users reported discomfort in the low back region. Figure 9 shows the percentage of users who reported a clearly perceivable discomfort (discomfort rating > 2) against various body parts. Figure 10 shows the percentage of users who reported a severe discomfort (discomfort rating > 4) against various body parts while figure 11 shows the same result segment wise.
71% 70%
62% 45%
51% 46%
38% 39%
20% 40% 60% 80%
Mileage Comfort
Power/performance Looks/style
Reliability/service/quality Ride & Handling
Cost Brand
Top three Considerations while buying a motorcycle
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Figure 9: Percentage of users who reported a clearly perceivable discomfort
Figure 10: Percentage of users who reported a severe perceivable discomfort
Figure 11: Percentage of users who reported a severe perceivable discomfort
4. Discussion The mean height and weight of the 178 users who participated in this study is higher than the corresponding values of Indian population found by Size India project, this could be partially due to lower age of the users in this study as compared to the size India project and selection of users only from cities. The general statistics of this study sample show that the mean age of premium segment users is significantly lower than that of economy segment and gearless step through segment (students t-test, p<0.05). This is well known to
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motorcycle manufacturers in India as premium segment motorcycles are generally targeted for younger users. However, the results of this survey also show that the height and weight of the premium segment users is higher than the users of other segments which is an important consideration in design of motorcycles for this segment. This survey reinforces the common understanding that motorcycles are predominantly used for commuting in India. The results also show that use of motorcycle for house hold works is very high, therefore it would be useful to consider provision of features in motorcycles that can aid the user in common house hold activities. The top considerations when buying a motorcycle clearly vary with the segment. Comfort is the only parameter that is among the top three considerations for all the segments. This result emphasizes the need of ergonomics and human factors in the design of motorcycles. The results of the discomfort survey showed that majority of motorcycle users have discomfort in the neck, back, buttocks, wrists and shoulders, the discomfort in legs is generally lower. This result is in agreement with that of a similar study in Malaysia (Karmegam 2009). Further more than 25% of the users reported severe discomfort in low back and buttocks (figure 10) which is significantly higher than other body parts (paired t-test, p < 0.05). There is also considerable variation in the patterns of discomfort between different segments of motorcycles (figure 11), about 27% of the users report severe low back discomfort and 11% users report severe wrist discomfort in the economy and gearless step through segment as against 20% and 18% respectively in the premium segment. This is primarily due to the difference in the riding posture between these segments. The premium segment motorcycles have a forward leaning posture that reduces the load on the back and increases the load on the wrist. An EMG based study also showed that the fatigue of lower back muscles is lesser in a forward leaning posture (Sai Praveen Velagapudi, 2010). These results indicate that the riding posture, especially the lumbar spine, seat, handgrips and controls are the important aspects in design for research on motorcycle ergonomics. 5. Conclusion This is a preliminary study in motorcycle ergonomics to understand the usage patterns and discomfort of motorcycle users in urban India. The study has been conducted across five cities in India and a total of 178 useful responses have been obtained. The study showed that motorcycles of all segments are predominantly used of household activities and commuting to work. The results also show that comfort is a very important consideration when buying a motorcycle and motorcycle users experience considerable discomfort in low back, buttocks, neck and wrists due to motorcycle usage. The results reinforce the need of research in motorcycle ergonomics and give important insights for both research on motorcycle ergonomics and design of motorcycles.
Acknowledgements We would like to thank R. Babu & K. Venkata Manga Raju for their advice and valuable guidance during the study. We would also like to thank all the volunteers who have taken time out of their busy schedule and participated in the study. Finally we would like to thank N Jayaram and the management of TVS Motor Company for their support in completing and publishing this work.
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