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Test vehicle techniques (often referred to as “floating car”) are the most common travel time collection methods and consist of a vehicle(s) that is specifically dispatched to drive with the traffic stream for the express purpose of data collection. Data collection personnel within the test vehicle control the speed of the vehicle according to set driving guidelines (“average car”, “floating car”, or “maximum car”:   A passenger in the test vehicle manually record travel times at designated checkpoints using a clipboard and stopwatch, or computer instrumentation may be used to record vehicle speed, travel times or distances at preset checkpoints or intervals.

A GPS receiver coupled with a laptop computer can be used to record the test vehicle’s position and speed at time intervals as frequent as every second.

License plate matching techniques consist of collecting vehicle license plate characters and arrival times at various checkpoints, matching the license plates between consecutive checkpoints, and computing travel times from the difference between arrival times.
 
The manual method involves recording license plate characters using voice tape recorders, then later transcribing the license plates into a computer for subsequent matching.

A portable laptop computer-based method relies on human observers to transcribe the license plate numbers into the computer in the field, then match the license plates by computer at a later time.

Video cameras or camcorders can also be used to collect license plates information  for late analysis.