Simulator: the NPC can't be static

[qwetqwe]

Hi team,
when I use api to control simulator, I add a NPC and api code is like this. But after a while, the NPC run by it self even if I set velocity to zero and follow_closest_lane to false.

import os
import lgsvl
import math
sim = lgsvl.Simulator(os.environ.get("SIMULATOR_HOST", "localhost"), 8181)
if sim.current_scene == "BorregasAve":#SanFrancisco
  sim.reset()
else:
  sim.load("BorregasAve")
orientation=lgsvl.Vector(0,0,0)
tr=sim.map_from_gps(northing=4141514,easting=587033.53,altitude=0,orientation=0)
print(tr)
spawns = sim.get_spawn()
state = lgsvl.AgentState()
state.transform = tr
state.transform.rotation=spawns[0].rotation
forward = lgsvl.utils.transform_to_forward(spawns[0])
print("foward state:",forward)
state.velocity = 0 * forward
#state.transform=spawns[0]
a = sim.add_agent("vehicle_Lincoln2017MKZ", lgsvl.AgentType.EGO, state)
a.connect_bridge("192.168.1.102", 9090)
state.velocity = 0 * forward
state.transform.position=state.transform.position+30*forward
npc1 = sim.add_agent("Sedan", lgsvl.AgentType.NPC, state)
npc1.follow_closest_lane(False, 0)
sim.run(time_limit = 0)

[ntutangyun]

what happens if you remove this line npc1.follow_closest_lane(False, 0)

[qwetqwe]

@ntutangyun it is the same

[EricBoiseLGSVL]

@qwetqwe We will look at this to see what is going on, thanks

[hadiTab]

@qwetqwe I was able to reproduce this with your script. We will look into it. Thanks.

[shalinmehtalgsvl]

Hi @qwetqwe ,

I believe this is just because the NPC is getting a non-zero speed after being dropped. I edited your script to use the raycast function and get points on the ground where the NPC can be spawned.

Can you try this change? This block replaces the line state.transform.position=state.transform.position+30*forward

# state.transform.position=state.transform.position+30*forward
up = lgsvl.utils.transform_to_up(tr)
layer_mask = 0
for bit in [0, 10, 11, 12]: # do not put 9 here, to not hit EGO vehicle itself
  layer_mask |= 1 << bit
hit = sim.raycast(state.transform.position+30*forward, -up, layer_mask)
state.transform.position = hit.point

[qwetqwe]

@shalinmehtalgsvl ,
it works,and car doesn't move. I thought that npc1.follow_closest_lane(False, 0) can brake the car.
thanks a lot