Investigation on Driving Habits of Chinese Truck Driver

Abstract

The understanding on driving habit is the essential foundation for human-machine interface design of truck cab. In order to obtain the truck driver’s characteristics and driving habits, an investigation was made on Chinese truck driver. The methods of one to one discussion and driving behaviour record were used in the investigation. Through the study, the characteristics of Chinese truck driver user group, driving schedule and behaviour habits, and the main factors affecting the current driving comfort were obtained. It is conluded that the primary practitioners of truck driving in China were young males. The majority of truck driving tasks were carried out in the daytime with long hours driving. Turck drivers had certain behaviour habits, such as steering wheel gripping mode and the usage of foot pedal. The improvement on devices ergonomics were expected, including seat size and back shape, steering wheel grip size, seat belt fixed position, mirrors adjustment, foot pedal, etc. The results were helpful for understanding Chinese truck driver group features and needs, as well as providing references for design of the truck cab.

1 Introduction

Driving comfort of the truck makes great contribute to road safety and driver’s health. As the essential foundation for human-machine interface design of truck cab, driving habit is expected to be understood in the design period. However, in the current domestic design process, the consideration on driving habits is insufficient, which results in inconveniences and safety risks on road. For instance, because of the lack of survey on driver’s habit of driving posture, as well as unsuitable seat design, a large amount of truck drivers felt tired and back uncomfortable very soon on road [1]. If it is a long distance driving, the driver’s control on the vehicle is impaired strongly [2]. The solution is to take full account of the driver’s characteristics and driving habits in the design process of truck cab. This paper aims to obtain the truck driver’s population characteristics and driving habits.

Based on the above considerations, the characteristics of Chinese truck driver user group, driving schedule and behaviour habits, and the main factors affecting the current driving comfort were obtained by the investigation. The results were helpful for understanding Chinese truck driver group features and needs, as well as providing references for human machine interface design of the truck cab.

2 Research Contents and Methods

2.1 Research Contents

The methods of one to one discussion and driving behaviour record were used in the investigation. The primary topics in this investigation were as follows.

• Truck driver group characteristics, including gender, age, anthropometry and occupational distribution.

• Driving schedule habits, including driving frequency, driving time, rest time, driving duration, tolerance to fatigue.

• Driving behaviour habits, including steering wheel gripping mode and adjustment, sitting posture and seat adjustment, pedal and brake using frequency and habit on different type of road, mirror using habit and adjustment, dashboard and switch buttons using habit and adjustment, etc.

2.2 Research Methods and Implementation

• (1) One to one investigation

According to the research content, the truck driving habits investigation questionnaire was developed. The investigation was carried out in the form of one to one discussion, which was prior to the driving behaviour record.

• (2) Driving behaviour record

Driving behaviours of the truck drivers were recorded by two sets of traffic recorder. The first set of the recorder was placed on the lower left side for recording the driver’s foot operation. The second set of the recorder was placed on the right side window of the cab for recording the driver’s arm action, body posture, seat postion and driving scenes. The driving tasks were basic road operation, including straight drives, turns, brakes and stops. Two types of road conditions, urban roads and highways, were considered. The actural driving habits were find out by the analysis of driving behaviours records.

The one to one investigation and driving behaviour record was conducted in Daxing and Changping District, Beijing, China. Seven truck drivers participated in the study. All of them had the valid driver license and more than one year truck driving experience. Drivers who had completed the investigation and driving tasks were given cash as rewards.

3 Results

3.1 Truck Driver Group Characteristics

Participants’ age were between 26 to 45 years old (35.43 ± 7.21). Their heights were 174.00 ± 1.41 cm, weight 77.14 ± 7.65 kg. It can be seen that the truck drivers were all young males, whose physical function were at the best level of human being life, such as reaction speed, strength and endurance.

According to Chinese National Standard, GB10000-88 Human dimensions of Chinese adults, the P50 height of males from 18 to 60 is 167.8 cm, the P90 height is 175.4 cm, the P95 weight is 75 kg, the P99 weight is 83 kg [3]. Taking account of the tendency of Chinese adults’ body dimension and weight keeping increasing in recent years, it could be classified that the overall height level of the participants was medium-high, the weight was medium-heavy.

All participants were self-employed, no one employed by delivery company.

3.2 Driving Schedule Habits

The investigation of driving schedule is related with driving frequency, driving time, rest time, driving duration, tolerance to fatigue.

Participants reported that all of them did driving tasks on each day. In the past one year, the least mileage drived by participants was 25,000 km; the majority of drivers drove from 30,000 to 60,000 km; the largest mileage was 130,000 km. The majority of drivers drove in the daytime, the minority drove at night. Within 24 h, the total driving duration (excluding rest time) of most drivers was from 3 h to 5 h; the minority drove from 2 h to 6 h.

For most of the drivers, the significant feeling of fatigue appeared after driving continuously 3 h to 4 h. A small number of drivers felt the fatigue after 3 h to 6 h. One of the participants reported that the fatigue was dull until driving continuously 12 h to 13 h. The total driving duration overall was 4 h to 6 h mostly, very few was up to 11 h.

3.3 Driving Behaviour Habits and Related Driving Experience

• (1) Steering wheel gripping mode

The most common steering wheel gripping mode (driving straight) was gripping by two hands with the right hand on higher position (see Fig. 1); or gripping by left hand with the right hand hanging or resting on the gear lever (see Fig. 2); or gripping by right hand with left hand hanging or resting on the door frame (see Fig. 3). The minority of dirvers gripped the steering wheel by two hands with the same height, or with the left hand on higher position. None of the participants gripped the steering wheel by two hands with reverse gesture.

Fig. 1.

Gripping by two hands

Fig. 2.

Gripping by left hand

Fig. 3.

Gripping by right hand

The majority of participants were satisfied with the steering wheel diameter. But they complained that the grip size was small. The steering wheel sleeve had to be used to fix this problem. The adjustment range of steering wheel height and angle was appropriate for all participants. The participants evaluated the feedback force of the steering wheel was comfortable and easy to operate, except one of the participants evaluated the steering wheel was heavy and difficult to operate.

• (2) Sitting posture and seat adjustment

The participants reported that the adjustment on seat was same regardless of the road conditions (highway, urban or rural roads). Whether driving in daytime or at night, the adjustment on seat, steering wheel, rearview and driving posture was same.

The air cushion seat was used on all of the participants’ truck. Its adjustable height range was about 10 cm. The majority of participants felt the seat height was suitable; two participants felt the seat height was too high even after adjustment; one participant felt the seat waved during driving. The adjustable front-rear range was suitable for the participants except one participant complained uncomfortable.

The position of the seat height adjustment device was good for most of the participants. The minority of participants were unsatisfied with it because they had to get off the truck to do the adjustment. The position of the seat front-rear adjustment device was suitable for all of the participants.

Participants were satisfied with the seat depth and seat hardness. Some complains and suggestions related with the seat were given by participants as follows.

• The seat back was uncomfortable. The improvement of headrest, back cushion and waist support were expected.

• The seat surface was small. A wider seat was expected.

• The distance between the steering wheel and the seat was small. It should be wider.

• The shock absorption capability of seat should be improved.

• The seat belt could not across the shoulder properly for a few participants. The imporvement of the seat belt positon was expected.

• (3) The usage of foot pedal

The using frequency of the foot pedal, from high to low, was the accelerator pedal, the clutch pedal and the brake pedal.

The using frequency of foot pedal was affected by road condition. On the highway, the accelerator pedal was used the most frequently; on the urban road, the three types of foot pedal were used as equivalent frequency; on the rural road, the acceleration and clutch were used more than brake pedal.

All of the participants felt the operation force needed by the accelerator pedal was suitable. Most of the praticipants felt the operation force needed by the clutch pedal and the brake pedal was suitable. A few participants complained the operation force needed by the clutch pedal and the brake pedal was large. The distance between the accelerator pedal and the brake pedal was appropriate. Participants reported that the feeling of foot fatigue was strong after one day’s driving work, especially the right feet.

The operating force of pulling the handbrake was suitable for all of the participants. The operating force of shifting gears was suitable for most of the participants except one participant complained the force was large. Most of the participants thought the size of the gear lever handle was appropriate, a few participants felt the handle size was small.

• (4) Mirror adjustment

Most of the participants did not adjust the rearview mirror during driving. One participant reported he adjusted the left rear view mirror sometimes during driving.

The participants reported that the adjustment of the left rearview mirror was easy. But the vast majority of participants reported that the right rearview mirror was difficult to be adjusted. In order to adjust the right rearview mirror, the driver had to get off the truck or assisted by another person.

The biggest outside blind areas were near the the right front wheel and the rear of the truck. The participants reported it was inconvenient to check these areas.

• (5) The usage of truck electronic system

The usage frequency of truck electronic system is shown in Table 1. Driving condition and non-driving condition were considered. The numbers in the table represented the amount of participants.

Table 1. The usage frequency of truck electronic system

The frequently used controllers of electronic system were expected to be located at easy touched area. The participants reported that the manual adujstment of swithes/buttons on the console was convenient, no matter it was in driving condition or non-driving condition. On most of the trucks, the controllers of entertainment system, air condition system and some other electronic system were laid on the console. However, on some of the trucks, the controllers of entertainment system were laid overhead of the driver. The involved participants said it was hard to operate in driving condition because of its requirement to eyes. All of the participants were satisfied with the postion of inside lights’ switches, which were located at the roof. Some of the participants complained the glove box was a little bit far from driver.

4 Conclusion

According to the investigation, the following conclusions could be obtained related with the characteristics of Chinese truck driver user group, driving schedule and behaviour habits.

• (1) The primary practitioners of truck driving in China were young males.

• (2) The majority of truck driving tasks were carried out in the daytime with long hours driving.

• (3) Turck drivers had certain behaviour habits, such as steering wheel gripping mode and the usage of foot pedal.

• (4) The improvement on devices ergonomics were expected, including seat size and back shape, steering wheel grip size, seat belt fixed position, mirrors adjustment, foot pedal, etc.

The results were helpful for understanding Chinese truck driver group features and needs, as well as providing references for design of the truck cab. More efforts should be done on improving truck drivers’ safety and health.