访问Webots中的红绿灯状态

Question

我需要访问当前状态中的红绿灯Webots。

检查“generic_traffic_light.c”控制器通用红绿灯，我们有：

WbDeviceTag red_light; 
red_light = wb_robot_get_device("ref light"); 
... 
wb_led_set(red_light, 1); 

假设我使用一些通用的红绿灯，是有可能有访问每个红绿灯状态？

我可以得到我的普通红绿灯的节点：

Node *traffic_node = supervisor->getFromDef("traffic_light_1"); 

但Node没有任何Device方法或任何LED - 相关Field。

非常感谢您的帮助

Answer 1

一个解决方案，以便能够从主管得到红绿灯状态将设置从控制机器人的“数据”字段中的状态。

然后您将能够从主管读取它。这是如“generic_traffic_light.c”的修改版（我刚刚加入到“wb_robot_set_data”几个调用）：

#include <webots/robot.h> 
#include <webots/led.h> 

#include <stdio.h> 
#include <string.h> 

#define TIME_STEP 512 
enum {GREEN_STATE, RED_STATE, ORANGE_STATE_TO_RED, ORANGE_STATE_TO_GREEN}; 

int main(int argc, char **argv) { 
    wb_robot_init(); 
    double red_time = 20.0; 
    double green_time = 20.0; 
    double orange_time = 1.5; 
    int current_state = GREEN_STATE; 

    if (argc > 1) { 
    sscanf(argv[1],"%lf",&red_time); 
    if (argc > 2) { 
     sscanf(argv[2],"%lf",&green_time); 
     if (argc > 3) { 
     if (strcmp(argv[3], "r") == 0) 
      current_state = RED_STATE; 
     else if (strcmp(argv[3], "g") == 0) 
      current_state = GREEN_STATE; 
     else if (strcmp(argv[3], "og") == 0) 
      current_state = ORANGE_STATE_TO_GREEN; 
     else if (strcmp(argv[3], "or") == 0) 
      current_state = ORANGE_STATE_TO_RED; 
     } 
    } 
    else 
     green_time = red_time; 
    } 

    WbDeviceTag red_light, orange_light, green_light; 
    red_light = wb_robot_get_device("red light"); 
    orange_light = wb_robot_get_device("orange light"); 
    green_light = wb_robot_get_device("green light"); 
    double last_phase_change_time = 0.0; 

    if (current_state == GREEN_STATE) { 
    wb_led_set(green_light, 1); 
    wb_robot_set_data("green"); 
    } else if (current_state == RED_STATE) { 
    wb_led_set(red_light, 1); 
    wb_robot_set_data("red"); 
    } else { 
    wb_led_set(orange_light, 1); 
    wb_robot_set_data("orange"); 
    } 

    while (wb_robot_step(TIME_STEP) != -1) { 
    double current_time = wb_robot_get_time(); 

    if (current_state == GREEN_STATE) { 
     if ((current_time - last_phase_change_time) >= green_time) { 
     current_state = ORANGE_STATE_TO_RED; 
     last_phase_change_time = current_time; 
     wb_led_set(green_light, 0); 
     wb_led_set(orange_light, 1); 
     wb_robot_set_data("orange"); 
     } 
    } else if (current_state == RED_STATE) { 
     if ((current_time - last_phase_change_time) >= red_time) { 
     current_state = ORANGE_STATE_TO_GREEN; 
     last_phase_change_time = current_time; 
     wb_led_set(red_light, 0); 
     wb_led_set(orange_light, 1); 
     wb_robot_set_data("orange"); 
     } 
    } else if (current_state == ORANGE_STATE_TO_RED) { 
     if ((current_time - last_phase_change_time) >= orange_time) { 
     current_state = RED_STATE; 
     last_phase_change_time = current_time; 
     wb_led_set(orange_light, 0); 
     wb_led_set(red_light, 1); 
     wb_robot_set_data("red"); 
     } 
    } else { //current_state == ORANGE_STATE_TO_GREEN 
     if ((current_time - last_phase_change_time) >= orange_time) { 
     current_state = GREEN_STATE; 
     last_phase_change_time = current_time; 
     wb_led_set(orange_light, 0); 
     wb_led_set(green_light, 1); 
     wb_robot_set_data("green"); 
     } 
    } 
    }; 

    wb_robot_cleanup(); 

    return 0; 
} 

然后，你需要改变“GenericTrafficLight” PROTO为了使“数据“现场看到，这里是一个修改版本：

PROTO GenericTrafficLight [ 
    field SFVec3f translation 0 0 0 
    field SFRotation rotation 0 1 0 0 
    field SFBool  startGreen TRUE 
    field SFFloat greenTime 60 
    field SFFloat redTime  15 
    field SFString state  "off" 
] 
{ 
%{ 
    local greenTime = fields.greenTime.value 
    if greenTime <= 0.0 then 
    greenTime = fields.greenTime.defaultValue 
    io.stderr:write("'greenTime' should be strictly positive.\n") 
    io.stderr:write("'greenTime' was reset to '" .. greenTime .. "'.\n") 
    end 
    local redTime = fields.redTime.value 
    if redTime <= 0.0 then 
    redTime = fields.redTime.defaultValue 
    io.stderr:write("'redTime' should be strictly positive.\n") 
    io.stderr:write("'redTime' was reset to '" .. redTime .. "'.\n") 
    end 
    local controllerArgs = '"' .. redTime .. ' ' .. greenTime .. ' ' 
    if fields.startGreen.value then 
    controllerArgs = controllerArgs .. 'g' 
    else 
    controllerArgs = controllerArgs .. 'r' 
    end 
    controllerArgs = controllerArgs .. '"' 
}% 
    Robot { 
    translation IS translation 
    rotation IS rotation 
    children [ 
     Pole { 
     slot [ 
      TrafficLight { 
      lamp_geometry TrafficLightStandardLampGeometry { 
      } 
      } 
     ] 
     } 
    ] 
    controller "generic_traffic_light" 
    controllerArgs %{= controllerArgs }% 
    data IS state 
    } 
} 

真诚，

大卫