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Controlled off-street trials examined a novel design of 'standardised junction.' The design included four junction arms, with a cycle reservoir on each approach, low-level cycle signals (LLCS), and a two-stage right-turn (2SRT). The study investigated how cyclists turned right in response to the signage, road markings, and traffic signals in this facility. Observational data were recorded to monitor cyclist behaviour. Perceptions were captured using questionnaires. Contracted drivers were employed to simulate moderate traffic conditions. When approaching red signals, cyclists chose to stop in the cycle reservoir about 90% of the time. About 95% of the time, cyclists responded correctly to LLCS. Utilisation of the 2SRT was about 25%; most of the time (75%) cyclists performed a 'standard' right turn. When cyclists approached on green signals (and were unable to merge with traffic due to trial safety restrictions), the majority (66%) preferred to use the 2SRT. This was supported by questionnaire responses about how cyclists would behave in the 'real-world.' There was evidence of a learning effect; increased experience with the facility may have led some cyclists to adjust their behaviour on subsequent attempts. Subjective ratings related to the ease of completing a right turn and perceived safety when doing so were generally high. [ABSTRACT FROM AUTHOR]

The combination of low-frequency lateral and roll motions experienced in tilting trains can provoke motion sickness. The incidence of sickness depends on vehicle design and subject demographics. Vehicle design affects the location of the centre-of-roll, which influences passenger perception of motion. Age and gender have large influences on susceptibility to sickness, but little is known about the effects of ethnicity and body size. This study investigated the influence of both the vertical position of the centre-of-roll and subject characteristics (ethnicity, weight, stature and sickness susceptibility) on sickness caused by fully roll-compensated lateral oscillation. It was hypothesised that sickness would be greater when full compensation occurred at the head than when full compensation occurred at the seat. Sixty subjects experienced a 0.2-Hz lateral oscillation combined with ±7.3° of roll, so that the lateral acceleration was fully compensated at either the seat surface or 800 mm above the seat (i.e. average head height). Illness ratings and symptom scores were recorded every minute for 50 min (i.e. during a 5-min acclimatisation period, a 30-min exposure period and a 15-min recovery period). Although the mean illness ratings were greater when full compensation occurred at the head than at the seat, the difference was not statistically significant. Weight and stature were not associated with motion sickness, but illness ratings were much greater in Asian subjects than in European subjects. It is concluded that differences in susceptibility between Asians and Europeans have a greater effect on motion sickness than the height of the centre-of-rotation during roll-compensated lateral acceleration. [ABSTRACT FROM PUBLISHER]

Roll compensation during cornering (aligning the feet-to-head axis of the body with the resultant force) reduces lateral acceleration, but how any improvement in comfort depends on the frequency of the acceleration has not previously been investigated. Seated subjects judged the discomfort caused by lateral oscillation, roll oscillation and fully roll-compensated lateral oscillation at each of seven frequencies (0.25-1.0 Hz). Irrespective of whether it was caused by pure lateral acceleration or gravitational acceleration due to pure roll, acceleration in the plane of the seat caused similar discomfort at frequencies less than 0.4 Hz. From 0.4 to 1.0 Hz, with the same lateral acceleration in the plane of the seat, there was greater discomfort from roll oscillation than from lateral acceleration. With fully roll-compensated lateral oscillation, discomfort was less than with either the lateral component or the roll component of the motion from 0.2 to 0.5 Hz, but discomfort increased with increasing frequency and caused similar discomfort to pure roll oscillation at 1.0 Hz., Practitioner Summary: Tilting can reduce passenger exposure to vehicle lateral acceleration when cornering, but how comfort depends on the frequency of motion was unknown. This study shows 'tilt-compensation' only improves comfort at frequencies less than 0.5 Hz. The findings affect tilting vehicles and the prediction of discomfort caused by low-frequency motions.