AP_Scripting: add bindings for E-Stop, Motor interlock and safety state

libraries/AP_Scripting/docs/docs.lua

@@ -1037,6 +1037,12 @@ function mount:get_attitude_euler(instance) end
 ---@class motors
 motors = {}
 
+-- Get motors interlock state, the state of motors controlled by AP_Motors, Copter and Quadplane VTOL motors. Not plane forward flight motors.
+---@return boolean
+---| true  # motors active
+---| false # motors inactive
+function motors:get_interlock() end
+
 -- desc
 ---@param param1 string
 function motors:set_frame_string(param1) end
@@ -1518,6 +1524,18 @@ function rc:get_pwm(chan_num) end
 ---@class SRV_Channels
 SRV_Channels = {}
 
+-- Get emergency stop state if active no motors of any kind will be active
+---@return boolean
+---| true # E-Stop active
+---| false # E-Stop inactive
+function SRV_Channels:get_emergency_stop() end
+
+-- Get safety state
+---@return boolean
+---| true # Disarmed outputs inactive
+---| false # Armed outputs live
+function SRV_Channels:get_safety_state() end
+
 -- desc
 ---@param function_num integer
 ---@param range integer

libraries/AP_Scripting/examples/Safety_States.lua

@@ -0,0 +1,36 @@
+-- This Script is a example of the safety states avalalbe to lua
+
+local last_armed
+local last_motors_armed
+local last_E_stop
+local last_safe
+function update()
+
+  local armed = arming:is_armed()
+  if armed ~= last_armed then
+    gcs:send_text(0, 'Vehicle armed: ' .. tostring(armed))
+  end
+  last_armed = armed
+
+  local motors_armed = motors:get_interlock()
+  if motors_armed ~= last_motors_armed then
+    gcs:send_text(0, 'Motors armed: ' .. tostring(motors_armed))
+  end
+  last_motors_armed = motors_armed
+
+  local E_stop = SRV_Channels:get_emergency_stop()
+  if E_stop ~= last_E_stop then
+    gcs:send_text(0, 'E-Stop active: ' .. tostring(E_stop))
+  end
+  last_E_stop = E_stop
+
+  local safe = SRV_Channels:get_safety_state()
+  if safe ~= last_safe then
+    gcs:send_text(0, 'Safe state: ' .. tostring(safe))
+  end
+  last_safe = safe
+
+  return update, 100
+end
+
+return update()

libraries/AP_Scripting/generator/description/bindings.desc

@@ -279,6 +279,8 @@ singleton SRV_Channels method get_output_scaled float SRV_Channel::Aux_servo_fun
 singleton SRV_Channels method set_output_norm void SRV_Channel::Aux_servo_function_t'enum SRV_Channel::k_none SRV_Channel::k_nr_aux_servo_functions-1 float -1 1
 singleton SRV_Channels method set_angle void SRV_Channel::Aux_servo_function_t'enum SRV_Channel::k_none SRV_Channel::k_nr_aux_servo_functions-1 uint16_t'skip_check
 singleton SRV_Channels method set_range void SRV_Channel::Aux_servo_function_t'enum SRV_Channel::k_none SRV_Channel::k_nr_aux_servo_functions-1 uint16_t'skip_check
+singleton SRV_Channels method get_emergency_stop boolean
+singleton SRV_Channels manual get_safety_state SRV_Channels_get_safety_state 0
 
 ap_object RC_Channel method norm_input float
 ap_object RC_Channel method norm_input_dz float
@@ -521,6 +523,7 @@ singleton AP::motors() depends APM_BUILD_TYPE(APM_BUILD_ArduPlane)||APM_BUILD_CO
 singleton AP::motors() literal
 singleton AP::motors() rename motors
 singleton AP::motors() method set_frame_string void string
+singleton AP::motors() method get_interlock boolean
 
 include AP_Common/AP_FWVersion.h
 singleton AP::fwversion() literal

libraries/AP_Scripting/lua_bindings.cpp

@@ -532,3 +532,11 @@ int lua_removefile(lua_State *L) {
   const char *filename = luaL_checkstring(L, 1);
   return luaL_fileresult(L, remove(filename) == 0, filename);
 }
+
+// Manual binding to allow SRV_Channels table to see safety state
+int SRV_Channels_get_safety_state(lua_State *L) {
+    binding_argcheck(L, 1);
+    const bool data = hal.util->safety_switch_state() !=  AP_HAL::Util::SAFETY_ARMED;
+    lua_pushboolean(L, data);
+    return 1;
+}

libraries/AP_Scripting/lua_bindings.h

@@ -12,3 +12,4 @@ int lua_get_CAN_device(lua_State *L);
 int lua_get_CAN_device2(lua_State *L);
 int lua_dirlist(lua_State *L);
 int lua_removefile(lua_State *L);
+int SRV_Channels_get_safety_state(lua_State *L);