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Re: [sumo-user] Questions on SUMO Built-In Functions (getSecureGap & brakeGap)

1) I'm only giving the corrections:
- myDecel and leaderMaxDecel are the values of vType attribute 'decel' attribute for the respective vehicles. This is a static value corresponding to the maximum desired deceleration. Note, that other carfollow models may interpret the same value differently when they override the functions getSecureGap, brakeGap etc.
- when calling brakeGap the headwayTime argument is sometimes myHeadwayTime and sometimes 0. See getSecureGap
- ACCEL2SPEED and SPEED2DIST are used to compute changes in speed and distance for one simulation step which may different from 1s. The formulas are in src/utils/common/SUMOTime.h. DELTA_T is the step-length in milliseconds hence TS = DELTA_T/1000

2) see

Am Mo., 13. Apr. 2020 um 14:37 Uhr schrieb Bae, Jong In <jbae42@xxxxxxxxxx>:

Eclipse SUMO is an open source, highly portable, microscopic and continuous road traffic simulation package designed to handle large road networks. It allows for intermodal simulation including ped...

  1. Could you verify the meaning of each argument of the two functions? 
  • myDecel - current deceleration rate of the subject vehicle (the one attempting to merge)
  • leaderMaxDecel - current deceleration rate of the leading vehicle (vehicle preceding to the lane change area)
  • speed - current speed of the subject vehicle
  • myHeadwayTime - Tau value of the subject vehicle (is this the same as headwayTime argument?)
  • leaderSpeed - current speed of the leader vehicle
  • ACCEL2SPEED - is the formula available? (the time.h file only says the formula as x/deltaT; what are these parameters?)
  • SPEED2DIST - is the formula available?

2. In the required gap equation = secureBackGap + subjectLength + subjectMinGap + secureFrontGap, how are 'secureBackGap' and 'secureFrontGap' determined in the 'getSecureGap'?
Is it simply using follower vehicle's deceleration and speed for 'secureBackGap' and leader vehicle data for 'secureFrontGap'?

Thank you in advance for your assistance.

-James Bae

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