Modified-comfortable-driving(MCD) 改进的舒适驾驶模型

[Ref]
  1. Jiang and Q. S. Wu. Cellular automata models for synchronized traffic flow. J. Phys. A theory. J. Phys. A 36, 381~390 (2003)

数学定义

慢启动规则的引入是为了描述驾驶员的不敏感的反应。一般认为静止车辆驾驶员没有运动车辆驾驶员敏感,因此静止车辆的慢化概率较大。然而,在这个模型中认为:刚停下的车辆的驾驶员仍十分敏感,只有停止时间超过一定时间 tc,驾驶员才会变得不那么敏感。
在MCD模型中,随机慢化函数为:
if (bn+1 and th< ts) then
p(vn(t), bn+1(t), th, ts) = pb
elif (vn == 0 and tst>= tc) then
p(vn(t), bn+1(t), th, ts) = p0
else
p(vn(t), bn+1(t), th, ts) = pd
演化规则为:
  1. 确定随机慢化概率: p = p(vn(t), bn+1(t), th, ts)
  2. 加速:
    if [(bn+1(t) == 0 or th>= ts) and vn(t) > 0] then
    vn(t+1) = min(vn(t) + 2, vmax)
    elif (vn(t) == 0) then
    vn(t+1) = min(vn(t) + 1, vmax)
    else
    vn(t+1) = vn(t)
  3. 减速:vn(t+1) = min(dneff , vn(t+1))
  4. 慢化:
    if(rand() < p) then
    vn(t+1) = max(vn(t+1) -1, 0)
  5. 确定刹车灯状态 bn+1(t+1):
    if (vn(t+1) < vn(t)) then
    bn(t+1) = 1
    elif(vn(t+1) > vn(t)) then
    bn(t+1) = 0
    else
    bn(t+1) = bn(t)
  6. 确定tst
    if (vn(t+1) == 0) then
    tst+= 1
    elif (vn(t+1) > 0) then
    tst= 0
  7. 位置更新: xn(t+1) = xn(t) + vn(t+1)