Motorcycles are considered as one of the extreme modes of conveyance contributing to road accidents. Reports revealed that the number of deaths caused by motorcycles is significantly higher than by any other means of transportation. A large percentage of motorcycle accidents occurred mainly due to human behaviour. The objectives of this paper are to unveil and analyse certain behavioural patterns of riders influencing the motorcycle mishaps through literature reviews on various aspects of riding behaviours including the lack of visibility and alertness, and speeding issues. This is important for a comprehensive and broad understanding of the riders' behavioural and performance traits associated with speeding, visibility, and alertness issues. Thus, collisions due to these issues may be avoided. This study summarizes 104 selected articles published in Springer, Elsevier, Tylor & Francis, IEEE, US Patent, WHO and others, distributed over the year of 1981 to 2019, which were further separated into four classes; 22 articles (21%) on the speeding issues, 25 articles (24%) on the visibility issues, 24 articles (23%) related to alertness issues, and 33 articles (32%) comprising of other studies related to motorcycles. All these research papers highlighted the ways to reduce the risks from speeding and to improve the visibility and alertness of motorcycle riders. As a conclusion, the study found that by applying the Intelligent Transport System (ITS) in motorcycles, road accidents may be reduced. It is also well noticed that the headlight of motorcycle and the use of fluorescent jacket increase the conspicuity of a motorcyclist. Moreover, the Daytime Running Light (DRL) of a motorcycle may also reduce accidents. It is also noted that the use of sensors on steering wheel increases the alertness of drivers. Finally, a framework to gain an improved understanding on the motorcycle riders' behaviour related issues and the ways to handling them were recommended. On top of that, this study had also suggested a new technological utilisation to improve the management of speeding, visibility and alertness issues. Provided that these concerns are addressed, a drop in the number of accident occurrences is possible.

A review of behavioural issues contribution to motorcycle safety

We present a wide-angle, broad-spectrum cylindrical lens based on reflections from an array of three-dimensional, high-aspect-ratio micro-mirrors fabricated on a cylindrical elastomeric substrate, functionally inspired by natural reflecting superposition compound eyes. Our device can perform one-dimensional focusing and beam-shaping comparable to conventional refraction-based cylindrical lenses, while avoiding chromatic aberration. The focal length of our cylindrical lens is 1.035 mm, suitable for micro-optical systems. Moreover, it demonstrates a wide field of view of 152° without distortion, as well as modest spherical aberrations. Our work could be applied to diverse applications including laser diode collimation, barcode scanning, holography, digital projection display, microlens arrays, and optical microscopy.

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Bio-Inspired Wide-Angle Broad-Spectrum Cylindrical Lens Based on Reflections from Micro-Mirror Array on a Cylindrical Elastomeric Membrane

The double-liquid focus-tunable lens based on electrowetting on dielectrics is attracting many researchers’ attention because of compact volume, quick responding speed, low consumption etc. In this paper, a focus-tunable liquid cylindrical lens based on electrowetting is designed, the structure and operating principles of this lens are introduced. COMSOL Multiphysics is chamber, and the focal length is varied continuously. According to the materials used in our laboratory, the focal length is estimated, ranging between (-∞, -38.6mm)υ(61.4mm, +∞).

Focus-tunable liquid cylindrical lens based on electrowetting

An efficient and uniform illumination system with a freeform mirror for a color-sequential LCOS pico projector based on LED is proposed in this paper. The novel homogenizer is composed of a micro lens array and a freeform mirror. A freeform mirror with XY polynomial profile is adopted for the reshaping of light pattern, the correction of keystone distortion and the folding mirror for the reduction of volume. Typically, the design of micro lens array, the aspect ratio of the lenslet is corresponding with that of the panel. However, the crosstalk phenomenon occurs due to each lenslet with different collecting angle in horizontal and vertical direction, especially when the aspect ratio of the panel in our study is 16:9. The crosstalk phenomenon not only reduces efficiency but also generates stray light on the panel. Therefore, we use a micro lens array with square lenslet to eliminate it. Subsequently, the square light pattern on the panel needs to be reshaped to fit the aspect ratio of the panel. A cylindrical mirror with a fixed power is used to compress the light pattern first. However, for the requirement of different focal distances from the cylindrical mirror to the panel on entire surface, it generates severe keystone distortion. A freeform mirror with progressive power variation is employed for the correction of keystone distortion with high overfilled efficiency and the reshaping of the light pattern fitting the ratio of the panel. In the results of optical simulation, JBMA uniformity on the panel is 98 % and the coupling efficiency from LED to the plane of the panel is 85 %. Furthermore, the alignment tolerance of the freeform mirror has also been discussed. Finally, the freeform mirror is fabricated by ultra-precision diamond milling process. The form accuracy and surface roughness of the freeform mirror are less than 0.5 um and 5 nm, respectively.

Freeform mirror for illumination system of color-sequential LCOS pico projector

We present an asymmetric condenser with an elliptical solid angle distribution and improves system efficiency of 15.5%.
The proposed system on the DMD achieves the light efficiency of 63.4% and the average deviation of 1.75%.

Using the toroidal and cylindrical lenses to project the RGB LEDs sources on the lens array with elliptic solid angle calculation for the DLP projector

The motorcycle headlamp is composed of a white LED module, an elliptical reflector, a parabolic reflector and a toric lens. We use non-sequential ray to improve the optical efficiency of the compound reflectors. Using the toric lens can meet ECE_113 regulation and obtain a good uniformity.

White LED motorcycle headlamp design

We apply a digital camera with two prism arrays to capture a stereo image of the corrected chromatic aberration and
distortion. The doublet prisms are used to correct chromatic aberration. The camera distortion with two prism arrays can
be increased, and reduced by the lens optimization.

Wen Shing Sun

Papers

Using the toroidal and cylindrical lenses to project the RGB LEDs sources on the lens array with elliptic solid angle calculation for the DLP projector

White LED motorcycle headlamp design

Double micro-prism array design for reducing dispersion on prism-based stereo camera system