MC-ProbMC-PrismFiles/car_pedestrian_mdp.prism

mdp

const int lanes = 5; // Counting the sidewalks as lanes
const int streetLength = 20;

const int maxVelocity = 3;
const int minVelocity = 1;

const int carLaneInit = 2;
const double probFalling = 2/9;

global move : [0..1] init 0; // 0: car 1: pedestrian

formula ped_at_edge = ped_street_pos = 1 | ped_street_pos = streetLength;

formula car_at_end = car_street_pos = streetLength;

// check ped within [car_pos-velocity..car_pos], same lane
formula crash_straight = (car_lane_pos=ped_lane_pos & ped_street_pos>=car_street_pos-velocity & ped_street_pos<=car_street_pos);
// check ped street pos within [car_street_pos-velocity..car_street_pos], ped lane pos within [car_lane_pos-1..car_lane_pos]
formula crash_left = (switched_left & ped_lane_pos>=car_lane_pos-1 & ped_lane_pos<=car_lane_pos & ped_street_pos>=car_street_pos-velocity & ped_street_pos<=car_street_pos);
// check ped street pos within [car_street_pos-velocity..car_street_pos], ped lane pos within [car_lane_pos+1..car_lane_pos]
formula crash_right = (switched_right & ped_lane_pos>=car_lane_pos+1 & ped_lane_pos<=car_lane_pos & ped_street_pos>=car_street_pos-velocity & ped_street_pos<=car_street_pos);

label "crashed" = crash_straight | crash_left | crash_right;
label "maxedOut" = velocity=maxVelocity;
label "pedCrossed" = ped_lane_pos=lanes;

module car

switched_right : bool init false;
switched_left : bool init false;

car_street_pos : [0..streetLength] init 0;
car_lane_pos : [2..lanes-1] init carLaneInit;
velocity : [minVelocity..maxVelocity] init minVelocity;

// TODO

endmodule


module pedestrian

ped_street_pos : [0..streetLength] init floor(streetLength/4);
ped_lane_pos : [1..lanes] init 1;
fell_down : [0..2] init 0; // 1-2: getting up

[move] move=1 & fell_down=0 -> ((1-probFalling)/4): (ped_lane_pos'=min(lanes,ped_lane_pos+1))     & (move'=0) +
                               ((1-probFalling)/4): (ped_lane_pos'=max(1,ped_lane_pos-1))     & (move'=0) +
                               ((1-probFalling)/4): (ped_street_pos'=min(lanes,ped_street_pos+1)) & (move'=0) +
                               ((1-probFalling)/4): (ped_street_pos'=max(1,ped_street_pos-1)) & (move'=0) +
                               (probFalling/4): (ped_lane_pos'=min(lanes,ped_lane_pos+1))     & (fell_down'=2) & (move'=0) +
                               (probFalling/4): (ped_lane_pos'=max(1,ped_lane_pos-1))     & (fell_down'=2) & (move'=0) +
                               (probFalling/4): (ped_street_pos'=min(lanes,ped_street_pos+1)) & (fell_down'=2) & (move'=0) +
                               (probFalling/4): (ped_street_pos'=max(1,ped_street_pos-1)) & (fell_down'=2) & (move'=0);
[getUp] move=1 & fell_down>0 -> 1: (fell_down'=fell_down-1) & (move'=0);

endmodule