Dr. Mark Nan Tu 涂南博士

1 Flight Modes
2 Major Flight Modes
3 MANUAL
4 STABILIZE
5 FLY BY WIRE_A (FBWA)
6 FLY BY WIRE_B (FBWB)
7 AUTOTUNE
8 TRAINING
9 ACRO
10 CRUISE
11 AUTO
12 Return To Launch (RTL)
13 LOITER
14 CIRCLE
15 GUIDED
16 Mission Specific Modes
17 TAKEOFF
18 LAND

ArduPlane has a wide range of built in flight modes. ArduPlane can act as a simple flight stabilization system, a sophisticated autopilot, a training system or a flight safety system depending on what flight mode and options you choose. Flight modes are controlled through the radio (via a transmitter switch) via mission commands or via ground station (GCS) commands.

To setup your radio to control APM’s Flight Modes use your ground station flight mode setup screen. In the Mission Planner use the Configuration -> Flight Modes screenArduPlane-flightmodes

The above setup shows a configuration for a RC transmitter with a 6 position switch (or a combination of a 3 position switch with a 2 position switch). Each switch position corresponds to a PWM (pulse width modulation) range shown on the right. Each of those switch positions is mapped to one of the available flight modes. In the above example, when the switch is in a position that generates a PWM value of between 1491 and 1620 then ArduPlane will enter Training mode.
上面的这张图展示了6个开关位置（或者一个3档位的开关和一个2档位的开关），每一个档位对应一个PWM数值。

Major Flight Modes (主要飞行模式）
All of the flight modes below have optional additional controls that may be used to change the behaviour to suit particular flying needs. After you have read the introductory material below it is highly recommended that you look through the complete set of ArduPlane parameters so you can explore the full range of functionality available.

MANUAL （手动，没有自稳定）
Regular RC control, no stabilization. All RC inputs are passed through to the outputs. The only ways in which the RC output may be different from inputs are as follows:

if a configured failsafe or geofence triggers, and ArduPlane takes control
if the VTAIL_OUTPUT option is enabled, then a software VTAIL mixer is applied on the output
if the ELEVON_OUTPUT option is enabled, then a software Elevon mixer is applied on the output

STABILIZE （自稳定）（通常用在室内或者起飞，降落时），没有GPS定位，只能保持水平方向平稳。高度，和位置完全靠手动。初学者必须练习和掌握的模式。
RC control with simple stabilization. If you let go of the sticks then ArduPlane will level the plane. This is a bit like flying a plane with a lot of dihedral. You will find that while it is possible to do maneuvers like rolls and loops in stabilize mode, the tendency of the plane to right itself will make these maneuvers difficult. For people wanting the plane to mostly fly itself, with the pilot just telling it where to fly, you are better off using the FlyByWireA mode.

In stabilize mode the throttle is limited by the THR_MIN and THR_MAX settings.

Note that STABILIZE mode is not a good mode to use for tuning the control loops. You are far better off using FBWA for that.

FLY BY WIRE_A (FBWA) （电控飞A），对于大多数新手来说，这是最常用的飞行模式，但事实上，基本没人飞这个模式。
This is the most popular mode for assisted flying in ArduPlane, and is the best mode for inexperienced flyers. In this mode ArduPlane will hold the roll and pitch specified by the control sticks. So if you hold the aileron stick hard right then the plane will hold it’s pitch level and will bank right by the angle specified in the LIM_ROLL_CD option (in centidegrees). It is not possible to roll the plane past the roll limit specified in LIM_ROLL_CD, and it is not possible to pitch the plane beyond the LIM_PITCH_MAX/LIM_PITCH_MIN settings.

Note that holding level pitch does not mean the plane will hold altitude. How much altitude a plane gains or loses at a particular pitch depends on its airspeed, which is primarily controlled by throttle. So to gain altitude you should raise the throttle, and to lose altitude you should lower the throttle. If you want ArduPlane to take care of holding altitude then you should look at the FlyByWireB mode.

In FBWA mode throttle is manually controlled, but is constrained by the THR_MIN and THR_MAX settings.

In FBWA mode the rudder is under both manual control, plus whatever rudder mixing for roll you have configured. Thus you can use the rudder for ground steering, and still have it used for automatically coordinating turns.

FLY BY WIRE_B (FBWB) （电控飞B） 和电控飞A一样，但是有能自动控制高度
The FBWB mode is similar to FBWA, but ArduPlane will try to hold altitude as well. The roll and pitch control is the same as FBWA,and altitude is controlled using the elevator. The target airspeed is controlled using the throttle.

To control your altitude in FBWB mode you use the elevator to ask for a change in altitude. If you leave the elevator centered then ArduPlane will try to hold the current altitude. As you move the elevator ArduPlane will try to gain or lose altitude in proportion to how far you move the elevator. How much altitude it tries to gain for full elevator deflection depends on the FBWB_CLIMB_RATE parameter, which defaults to 2 meters/second.

Whether you need to pull back on the elevator stick or push forward to climb depends on the setting of the FBWB_ELEV_REV parameter. The default is for pulling back on the elevator to cause the plane to climb. This corresponds to the normal response direction for a RC model. If you are more comfortable with the reverse you can set FBWB_ELEV_REV to 1 and the elevator will be reversed in FBWB mode.

If you have an airspeed sensor then the throttle will control the target airspeed in the range ARSPD_FBW_MIN to ARSPD_FBW_MAX. If throttle is mimimum then the plane will try to fly at ARSPD_FBW_MIN. If it is maximum it will try to fly at ARSPD_FBW_MAX.

If you don’t have an airspeed sensor then the throttle will set the target throttle of the plane, and ArduPlane will adjust the throttle around that setting to achieve the desired altitude hold. The throttle stick can be used to push the target throttle up beyond what it calculates is needed, to fly faster.

As with FBWA, the rudder is under a combination of manual control and auto control for turn coordination.

AUTOTUNE 自动调参是pixhawk一个比较牛逼的功能，再也不需要调节飞控的PID值，只要在空中开启自动调参，pixhawk自动设置PID值。不过实际上，飞机的高度是自动控制的，飞机会在空中来回摇晃几分钟，幅度越来越小。
The AUTOTUNE mode flies in the same way as FBWA, but it does automatic tuning of roll and pitch control gains. Please read the full documentation on AUTOTUNE for more details.

TRAINING 培训
This mode is like training wheels on a bicycle and is ideal for teaching students manual R/C control. If the roll is less the the LIM_ROLL_CD parameter than the pilot has manual roll control. If the plane tries to roll past that limit then the roll will be held at that limit. The plane will not automatically roll back to level flight, but it will prevent the pilot from rolling past the limit. The same applies to pitch – the pilot has manual pitch control until the LIM_PITCH_MIN or LIM_PITCH_MAX limits are reached, at which point the plane won’t allow the pitch to go past those limits.

In training mode the rudder and throttle are both completely under manual control.

ACRO （杂技）高级应用，主要用户是想玩电控飞A或者自平衡但是又不想全手动。
ACRO (for acrobatic) is a mode for advanced users that provides rate based stabilization with attitude lock. It is a good choice for people who want to push their plane harder than you can in FBWA or STABILIZE mode without flying in MANUAL. This is the mode to use for rolls, loops and other basic aerobatic maneuvers, or if you just want an “on rails” manual flying mode.

To setup this mode you need to set ACRO_ROLL_RATE and ACRO_PITCH_RATE. These default to 180 degrees/second, and control how responsive your plane will be about each axis.

When flying in ACRO the aircraft will try to hold it’s existing attitude if you have no stick input. So if you roll the plane to a 30 degree bank angle with 10 degrees pitch and then let go of the sticks, the plane should hold that attitude. This applies upside down as well, so if you roll the plane upside down and let go of the sticks the plane will try to hold the inverted attitude until you move the sticks again.

When you apply aileron or elevator stick the plane will rotate about that axis (in body frame) at a rate proportional to the amount of stick movement. So if you apply half deflection on the aileron stick then the plane will start rolling at half of ACRO_ROLL_RATE.

So to perform a simple horizontal roll, just start in level flight then hold the aileron stick hard over while leaving the elevator stick alone. The plane will apply elevator correction to try to hold your pitch while rolling, including applying inverse elevator while inverted.

In the current implementation the controller won’t use rudder while the plane is on it’s side to hold pitch, which means horizontal rolls won’t be as smooth as a good manual pilot, but that should be fixed in a future release. This also means that it won’t hold knife-edge flight.

Performing a loop is just as simple – just start with wings level then pull back on the elevator stick while leaving the aileron alone. The controller will try to hold your roll attitude through the loop. You can stop the loop upside down if you like as part of maneuvers such as Immelman turns or cuban eights.

Note that if you are using ACRO mode to try and teach yourself aerobatic flying then it is highly recommended that you setup a geo-fence in case you get disoriented.

Warning: It is very easy to stall your plane in ACRO mode, and if you stall you should change to MANUAL mode to recover

make sure you know the limitations of your airframe, and what the correct stall recovery procedure is. This varies a lot between airframes. Search for stall recovery tutorials for R/C aircraft and read them
don’t overload your airframe, only fly ACRO mode with a lightly loaded plane
make sure you have enough airspeed for whatever maneuver you are attempting. Throttle and speed control is completely under manual pilot control in ACRO mode
practice stall recovery before trying anything too fancy. Make sure you practice when you have plenty of altitude to give you time to try different recovery strategies
It can be a lot of fun flying ACRO mode, but you can also easily stall and crash hard. Automatic stall detection and recovery in autopilots is an area of research, and is not yet implemented in APM:Plane, so if you do stall then recovery is up to you. The best mode for recovery is MANUAL.

CRUISE （自动巡航）类似电控飞B，但是有机头锁定，较多用于长距离第一视角的飞行
Cruise mode is a bit like FBWB, but it has “heading lock”. It is the ideal mode for longer distance FPV flight, as you can point the plane at a distant object and it will accurately track to that object, automatically controlling altitude, airspeed and heading.

The way it works is this:

if you have any aileron or rudder input then it flies just like FBWB. So it holds altitude until you use the elevator to change the target altitude (at the FBWB_CLIMB_RATE rate) and it adjusts airspeed based on throttle
when you let go of the aileron and rudder sticks for more than 0.5 seconds it sets an internal waypoint at your current location, and projects a target waypoint one kilometre ahead (note that heading lock will only activate if you have GPS lock, and have a ground speed of at least 3 m/s)
as it flies along it heads for the target waypoint, and constantly updates that target to always be one kilometre ahead, leaving the previous waypoint as the position that you centred the aileron and rudder sticks
as long as you don’t touch the aileron or rudder, it will run the same navigation system it uses for waypoints, including crabbing, cross-track etc, so it will very accurately hold that ground course even in the face of changing wind conditions
One of the nicer aspects of CRUISE mode is how it handles rudder. If you give it some rudder then the roll controller will keep the wings level, but the plane will yaw with the rudder. So you get a “wings level” turn, allowing you to rotate your flight to point at whatever geographic feature you want to head towards. Then when you let go of the rudder it will head straight for that point.

Note that CRUISE mode does not currently have the ability to do terrain following. The ability to follow an altitude above ground level over variable terrain is planned for a future release of APM on the PX4 controller board.注意：目前还不能在飞机的高度方面自动跟随地面的高差改变

Warning: Make sure you only fly FPV if it is allowed by your countries flight and airspace control rules. Many countries do not allow non line of sight flight without a special operating license.

AUTO 自动，用在地面站控制，航点（按照GPS坐标）飞行。
In AUTO mode the follow a mission (a set of GPS waypoints and other commands) set by your ground station configuration. When entering AUTO mode ArduPlane will continue from whatever mission item it was last doing, unless you have reset the mission.

When in AUTO ArduPlane will by default allow the pilot to influence the flight of the plane by using “stick mixing”, which allows for aileron, elevator and rudder input to steer the plane in a way that can override the autopilot control. Whether this is enabled is determined by the STICK_MIXING option. By default stick mixing behaves the same as FBWA mode.

Warning: “Home” position is always supposed to be your Planes actual GPS takeoff location:
It is very important to acquire GPS lock before arming in order for RTL, Loiter, Auto or any GPS dependent mode to work properly.
For APM:Plane the home position is the postion of the Plane when you first get GPS lock whether it was armed or not.
This means if you execute an RTL in APM:Plane, it will return to the location where it was when it first acquired GPS lock.
For APM:Plane: Plug in the battery and let it acquire GPS lock where you want it to return to: (Not the Pits).
Return To Launch (RTL)
In RTL mode the plane will return to launch point (the point where the plane first got a GPS lock) and loiter there until manual control is regained (or it runs out of fuel!). As with AUTO mode you can also “nudge” the aircraft manually in this mode using stick mixing. The target altitude for RTL mode is set using the ALT_HOLD_RTL parameter in centimeters.

Alternatively, you may configure the plane to return to a Rally Point, rather than the launch point.

Warning: “Home” position is always supposed to be your Planes actual GPS takeoff location:
It is very important to acquire GPS lock before arming in order for RTL, Loiter, Auto or any GPS dependent mode to work properly.
For APM:Plane the home position is the postion of the Plane when you first get GPS lock whether it was armed or not.
This means if you execute an RTL in APM:Plane, it will return to the location where it was when it first acquired GPS lock.
For APM:Plane: Plug in the battery and let it acquire GPS lock where you want it to return to: (Not the Pits).
LOITER （GPS控制飞行），航拍最常用的模式。可以完全脱控，悬停。飞机移动比较慢，好比用GPS位置控制了飞机在3维空中的位置。
In LOITER mode the plane will circle around the point where you started the loiter, holding altitude at the altitude that you entered loiter in. The radius of the circle is controlled by the WP_LOITER_RAD parameter, but is also limited by your NAV_ROLL_CD limit, and your NAVL1_PERIOD navigation tuning.

As with RTL （自动返航，只要起飞的时候已经定位，那么切这个模式，飞机可以制动返航，并在20米的高度，慢慢降落到起飞的位置）and AUTO mode you can “nudge” the plane while in LOITER using stick mixing, if enabled.

Warning: “Home” position is always supposed to be your Planes actual GPS takeoff location: 自动返航点就是你的飞机上电以后找到的第一个的GPS地点（不管你开没开动马达），所以在以下飞行模式必须在GPS定位以后才能进行，比如RTL，定点定高，自动等
It is very important to acquire GPS lock before arming in order for RTL, Loiter, Auto or any GPS dependent mode to work properly.
For APM:Plane the home position is the postion of the Plane when you first get GPS lock whether it was armed or not.
This means if you execute an RTL in APM:Plane, it will return to the location where it was when it first acquired GPS lock.
For APM:Plane: Plug in the battery and let it acquire GPS lock where you want it to return to: (Not the Pits).

CIRCLE 画圆（类似定点定高，但是不需要GPS定位）（这个模式比较好玩，主要用在航拍一个点，比如宝塔，飞机围绕宝塔转圈，机头永远对着宝塔，半径可调，初设20米）
Circle mode is similar to loiter, but doesn’t attempt to hold position. This is primarily meant as a failsafe mode and is the mode that the aircraft will enter by default for 20 seconds when a failsafe event occurs, before switching to RTL （一键返航）.

Circle mode is deliberately a very conservative mode, and doesn’t rely on GPS positioning as it is used when GPS fails. It will do a large circle, The bank angle is set to the LIM_ROLL_CD divided by 3, to try to ensure the plane remains stable even without GPS velocity data for accelerometer correction. That is why the circle radius is so large.

Circle mode uses throttle and pitch control to maintain altitude at the altitude where it started circling.

GUIDED （导航）主要用于在地面站的数字地图上点击某个位置，然后飞机自动飞过去，另外一个用处，就是地理限围，飞机飞过边界以后，自动进入导航模式，会自动飞到一个返航地点并定点定高，等待下一个操作指令
The GUIDED mode is used when you want the aircraft to fly to a specific point on the map without setting up a mission. Most ground control stations support a “click to fly to” feature where you can click a point on the map and the aircraft will fly to that location when loiter.

The other major use for GUIDED mode is in geo-fencing. When the geo-fence is breached the aircraft will enter GUIDED mode, and head to the predefined geo-fence return point, where it will loiter until the operator takes over.

Mission Specific Modes
When flying an AUTO mission ArduPlane has some sub-modes that are set using mission items. The two main sub-modes are TAKEOFF and LAND.

TAKEOFF 起飞，通常用在使用地面站或者手机控制，自动起飞，到20米高度，然后自动悬停。
Auto takeoff is set by the mission control scripting only. The takeoff mission specifies a takeoff pitch and a target altitude. During takeoff ArduPlane will use the maximum throttle set by the THR_MAX parameter. The takeoff mission item is considered complete when the plane has reached the target altitude specified in the mission.

Before takeoff it is important that the plane be pointing into the wind, and be aligned with the runway (if a wheeled takeoff is used). The plane will try to hold its heading during takeoff, with the initial heading set by the direction the plane is facing when the takeoff starts. It is highly recommended that a compass be enabled and properly configured for auto takeoff, as takeoff with a GPS heading can lead to poor heading control.

If you are using a wheeled aircraft then you should look at the WHEELSTEER_* PID settings for controlling ground steering. If you are hand launching or using a catapult you should look at the TKOFF_THR_MINACC and TKOFF_THR_MINSPD parameters.

LAND 降落
Auto Land is set by the mission control scripting only. Throttle and altitude is controlled by the autopilot. After getting closer LAND_FLARE_ALT meters from the target altitude or LAND_FLARE_SEC seconds from the target landing point the plane will “flare” to the LAND_PITCH_CD pitch (in centidegrees) and will hold heading for the final approach.

Setting up ArduPlane for reliable auto-takeoff and landing is very airframe dependent, and it is recommended that you first get some experience flying your aircraft in FBWA mode, and be ready to take over control in manual or FBWA mode the first few times you use an automatic takeoff or landing.

You should also look through the complete list of parameters, as there are a lot of parameters that help control takeoff and landing for different situations.

1、稳定模式Stabilize
稳定模式是使用得最多的飞行模式，也是最基本的飞行模式，起飞和降落都应该使用此模式。
此模式下，飞控会让飞行器保持稳定，是初学者进行一般飞行的首选，也是FPV第一视角飞行的最佳模式。
一定要确保遥控器上的开关能很方便无误地拨到该模式，这对抢救紧急情况十分重要！

2、定高模式ALT_HOLD
初次试飞之后就可以尝试定高模式，此模式不需要GPS支持，APM会根据气压传感器的数据保持当前高度。
定高时如果不会定点，因此飞行器依然会漂移。可以遥控来移动或保持位置。
定高时就是APM控制油门来保持高度。但仍然可以用遥控油门来调整高度，不可以用来降落，因为油门不会降到0。
稳定模式和定高模式之间切换时，要让遥控发射机的油门在同一位置，避免因模式切换、油门控制方式发生变化造成飞行器突然上升或者下降。

3、悬停模式Loiter
悬停模式就是GPS定点模式。应该在起飞前先让GPS定点，避免在空中突然定位发生问题。其他方面跟定高模式基本相同。

4、简单模式Simple Mode
设置过APM飞行模式的朋友都会注意到，软件界面的各个模式旁边，都有个“Simple Mode”简单模式的勾选框。勾了这个框之后的模式，飞行中会更加简单：
不用再管飞行器机头的朝向，可以将飞行器看成一个点，如果升降舵给出俯冲指令，飞行器就会飞得远离操作者；反之如果给出拉杆指令，飞行器会飞回操作者；给出向左滚转的指令，飞行器会向左飞，反之亦然。。。注意，这些前后左右的飞行，是不管当时的机头指向的！

5、返航模式RTL
返航模式需要GPS定位。GPS在每次ARM前的定位点，就是当前的“家”的位置；GPS如果在起飞前没有定位，在空中首次定位的那个点，就会成为“家”。
进入返航模式后，飞行器会升高到15米，或者如果已经高于15米，就保持当前高度，然后飞回“家”。
还可以设置高级参数选择到“家”后是否自主降落，和悬停多少秒之后自动降落。

6、绕圈模式Circle
当切入绕圈模式时，飞行器会以当前位置为圆心绕圈飞行。而且此时机头会不受遥控器方向舵的控制，始终指向圆心。
如果遥控器给出横滚和俯仰方向上的指令，将会移动圆心。
与定高模式相同，可以通过油门来调整飞行器高度，但是不能降落。
圆的半径可以通过高级参数设置调整。

7、指导模式Guided
此模式需要地面站软件和飞行器之间通信。连接后，在任务规划器Mission Planner软件地图界面上，在地图上任意位置点鼠标右键，选弹出菜单中的“Fly to here”（飞到这里），软件会让你输入一个高度，然后飞行器会飞到指定位置和高度并保持悬停。

8、跟随模式FollowMe
跟随模式基本原理是：操作者手中的笔记本电脑带有GPS，此GPS会将位置信息通过地面站和数传电台随时发给飞行器，飞行器实际执行的是“飞到这里”的指令。其结果就是飞行器跟随操作者移动。
由于此模式需要额外的设备，暂时不讨论。

9、自动模式Auto
此模式下飞行器会自动执行地面站Mission Planner设定好的任务，例如起飞、按顺序飞向多个航点、旋转、拍照等。
此模式内容丰富，会另行详细介绍。

10: 手动：MANUAL （完全手动，没有自稳定）

11: 自动起飞，TAKEOFF 通常用在使用地面站或者手机控制，自动起飞，到20米高度，然后自动悬停。

12: 自动降落 LAND，顾名思义，就是用手机或者地面站控制，自动降落。要保证地面水平哦，否则。。。

13:自动调参AUTOTUNE 是pixhawk一个比较牛逼的功能，再也不需要调节飞控的PID值，只要在空中开启自动调参，pixhawk自动设置PID值。不过实际上，飞机的高度是自动控制的，飞机会在空中来回摇晃几分钟，幅度越来越小。