Rider case example

Suppose someone is planning a bicycle trip from Baltimore, Maryland to Washington D.C. The actual mileage will be determined by where the rider starts and ends the trip, and the route taken. While planning the trip, the rider does not need to know the actual mileage. All the rider needs is an estimate, which in this case would he about 39 miles. People need to know when an estimate is acceptable and when it is not. For example, you could use an estimate when buying material to sew curtains for a window. You would need more exact measurements when ordering custom shades for the same window. 

Rider monitoring systems for PTWs experts point out that it could help PTWs in case of fatigue, inattention, etc., and they suggest the need for research. Rider monitoring systems on PTW need to be more complex than car systems. Video monitoring for example is hardly feasible, due to helmet and motorcycle clothing. There are very few studies and research works in this field. 

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