Use of a H∞ controller on a half semi-trailer truck model to reduce vibrations and its implications on human factor

© Springer Nature Switzerland AG 2019.Comfort of a large goods vehicle driver has a crucial factor on fatigue one of which being physical (muscular) fatigue, which has common indicators of pain in the back and legs caused by prolonged voluntary and involuntary muscle activities as an attempt by the body to counteract the vibrations induced via the seat. Therefore, drivers working under uncomfortable driving conditions, encounter ergonomic problems, increased fatigue and require additional rest time. Consequently, these rests increase both in time and numbers resulting with lost logistics time and reduced efficiency. Additionally, these drivers suffer from medical issues both physically and mentally. It is shown that muscular health complaints is mostly accompanied by mental health complaints (e.g.: stress, burnout etc.). These muscular and mental health complaints increase drivers need for recovery, however drivers undergo problems to recover from this work-related fatigue at the end of work day. Though it may be seen as an acute issue, in long term, the accumulation of restlessness may induce the development of psychosomatic health problems. Hence, drop in medical status and efficiency of drivers burden the organizations with major financial costs, via sickness absence of worker, compensations of absenteeism, errors or mistakes occurred at work caused by sudden pain, stress, and etc. Therefore an uncomfortable driving experience becomes not only a health issue for the drivers but also an economical inconvenience to the company. To increase comfort and prevent these issues a H∞ controller with a dynamic output feedback was proposed in this study. This controller was designed and modeled with linear matrix inequality (LMI) method, and implemented on a model of a half semi-trailer truck augmented with a human-seat couple model. Both uncontrolled and controlled cases were simulated and compared in terms of the comfort level of the driver with respect to ISO 2631 standard. As a result, controller decreased the root mean square (RMS) acceleration on the human-seat couple and increased the comfort. Originating from these results, a discussion was made in the perspective of human factor such that, reducing the vibration is not only meant to increasing comfort of driver, but also eliminating the negative effects of discomfort on safe driving and reducing fatigue