UAE Innovation Challenge 2015

ArduPilot Curriculum

Table of Contents
Install Mission Planner 3
Installing firmware for ArduPilot Mega(APM) 2.6 5
Setting Up Your APM Board 6 Connect the Autopilot 6 Initial Setup and Install Firmware 6 Connect to MavLink 7 Calibrating Hardware While connected to the APM Board 8  Accelerometer 8  Compass 9 Calibrating Hardware While Connected to the 3DR Telemetry Radio 11  Radio Calibration 11  Flight Modes 13  Battery Monitor 14  Airspeed Sensor 15
Flight Data Screen 17
Tuning your Airframe 19 Basic Tuning 19  PID’s (Proportional, Integral & Differential) 19  Period 20  Navigation Angles 20  Throttle 20  Airspeed 20  General Notes on Parameters 20 Recommended Process for Tuning When Starting with New Plane 21 Advice for Tuning: Poor Waypoint Reaction 22
Mission Planning 23 Recording and Playing Back Missions 24
First-time Flying Checklist 26 Ground Calibration 26 Launching in Auto Mode 26
Install Mission Planner

* The link to install the Mission Planner software can be found at: http://ardupilot.com/downloads/?did=82

* The installation utility will install the necessary drivers. You will probably get the following warning. Select "Install this driver software anyway."

* (Note: If you get a DirectX installation error, then your copy of Windows doesn't have an updated version of DirectX. Download that here: * http://www.microsoft.com/en-us/download/details.aspx?id=35 )

Installing firmware for ArduPilot Mega(APM) 2.6

* Once the software is downloaded, plug your APM board into your computer and wait for Windows to recognize it and install the right driver. Once APM is recognized, it will show up in your Windows Device Manger (shown below). * Your COM port number will vary based upon your computer or how many other devices you are using. Whichever number is listed in this device manager is the port you'll set when syncing your device with the software.

* Once you have installed the Mission Planner, it will display a notice if an upgrade is available and update itself. It is not necessary to run the installation utility again! * Do not click "Connect" yet! You must load the correct firmware for your vehicle first.
Setting Up Your APM Board
Connect the Autopilot * Connect the autopilot to your computer with a micro-USB cable.

Initial Setup and Install Firmware * Select your vehicle type. This will install the latest firmware you just downloaded onto your autopilot.

* APM Planner will notify you when the status bar reaches 100% and the firmware installation in complete.

Connect to MavLink * Select the correct port on the left drop down menu. * Select a Baud Rate of 115200 when there is a direct connection (your micro USB) between the APM and computer. * Select a Baud Rate of 57600 when you are connecting with your 3DR radio * Select connect.

* When connected, the status will display the green connected icon in the upper right hand corner as shown below.

Calibrating Hardware While connected to the APM Board * The APM must be calibrated the first time you integrate it into your plane as well as whenever there is a firmware update. * Click on the “Initial Setup” tab along the top of your Mission Planner screen. * You will calibrate your hardware with the menus under “Mandatory Hardware” and “Optional Harware” * Note: Do NOT use Wizard for your initial calibration

* Accelerometer * The APM board has 3 status LEDs, one red, one yellow and one blue. The meaning of the different LED states is as follows: * Red solid- Armed, motor will spin when throttle raised * Red blink- Disarmed, motor will not spin * Red double blink- disarmed, motors will not spin, cannot arm because of failure in pre-arm checks * Blue solid- GPS working, 3D lock * Blue blink- GPS working, no 3D lock * No Blue- GPS not working * Yellow blinking - only flashes along with red and blue as part of the in flight auto trim feature * Click on “Accel Calibration” on the left side of the screen. * Click on “Calibrate Accel” on the screen and follow the prompts that appear. * It will have you place your APM board on its back, nose, side, etc. * It is very important that you place the board as straight as possible in all the positions. If you do not, your plane might not respond correctly once in the air.

* Compass * The APM board has 2 status LEDs, one red and one blue. The meaning of the different LED states is as follows: * Red solid- Powered * Blue solid- GPS working, 3D lock * Blue blink- GPS working, no 3D lock * No Blue- GPS not working * Select “APM with External Compass” * Then “Live Calibration”

* The live calibration window will appear. Spin the APM board and compass along all its axes until the program has enough valid data.

* This message below indicates that your compass data has been successfully saved.

Calibrating Hardware While Connected to the 3DR Telemetry Radio * Plug one 3DR radio into your the telemetry port on your APM board. * Plug other 3DR radio into the computer with a micro USB cable. * 3DR Status LEDs * The 3DR Radios have 2 status LEDs, one red and one green. The meaning of the different LED states is as follows: * green LED blinking - searching for another radio * green LED solid - link is established with another radio * red LED flashing - transmitting data * red LED solid - in firmware update mode * Similar to the steps when the APM board was connected, you must select the appropriate COMM port for your 3DR radio (it will be different than the one used when the APM was connected) and select a baud rate of 57600. Then click Connect.

* Radio Calibration * This screen will determine how the radio your pilot holds will communicate with the plane when in flight. * Click “Calibrate Radio” in the lower right hand corner.

* Move the control sticks on your radio to their maximum positions in all directions until the gray bars are fully green. * If you have built a Flying Wing, you can configure your elevon settings in the “Elevon Config” area located below the bars.

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Reversing Servos and Setting Normal/Elevon Mode * First, make sure your control surfaces are going the right way in Manual Mode. In this mode, the RC controls are sent straight through to the servos, without going through the autopilot (this is the safety/failsafe mode that allows you to regain control even in the case of autopilot failure). If any control surface is going in the wrong direction when you move your RC sticks, use your transmitter’s channel reverse function to reverse it. * Second, switch into FBWA mode and do the same thing, while connected to the Mission Planner. You’re under autopilot control now, and you need to configure it for your particular setup. As you move the RC sticks again, watch the control surfaces. If any is going in the wrong direction, click the Reverse checkbox in the RC setup screen shown below. Do this for all four channels shown. Just because it’s right in RC/Manual doesn’t mean it will be right under Autopilot control. Check it in both modes!

* It takes a little trial-and-error to set up elevons on any particular aircraft, but here are the basic steps: * First, set it up in manual mode by setting up elevon mixing on your RC transmitter. It matters which elevon is plugged into which channel! Typically, the left wing elevons should be plugged into Ch1 and the right wing into Ch2, as shown above. * Still in manual mode, check to see if you have to reverse any channels on your RC transmitter to ensure the control surfaces move the way they should in both pitch and roll. * Now that it’s working in manual, connect to your APM board with the Mission Planner. Go through the regular setup process. When calibrating your RC input, don’t just move the elevator and aileron sticks to the normal up down, left right positions. Instead, you must move the stick to the CORNERS or the calibration will be wrong and the servos will try to move too far. This is because now that you’ve switched your RC transmitter into elevon mode, the elevator and airelon inputs are added when the stick is in the corner (full left and full up as an example). * While still in the MP RC setup screen, switch into FBWA Mode. Move the plane around to test and watch the control surfaces. When you tip the nose of the plane down, the two elevons should go up and vice versa. Likewise with roll; when you roll the plane, the elevons should move to counteract that and return the plane to level. You’ll probably have to reverse something with the check boxes on that screen for correct motion. Just change one thing at a time! * If you just can’t seem to find the right combination that works, try swapping your servo cables, so that Right is in Output 1 and Left is Output 2. This is something of a last resort, because you’ll have to start the setup from the top of this list again.
To learn about the behind the scenes of elevon mixing or the how to setup a VTAIL plane by enabling VTAIL mixing find out more here: http://plane.ardupilot.com/wiki/arduplane-setup/first-time-apm-setup/reversing-servos-and-setting-normalelevon-mode/ * Flight Modes * There are several different flight modes to choose from. These are controlled by your RC transmitter's three position toggle switch. When you move the toggle switch, you will see the green highlight change to a different line.

* You can use the drop-down menu on each line to assign that mode to a function. Note that Flight Mode 6 cannot be changed from Manual. It's "hardware manual", which means that it's controlled by the failsafe circuit on the APM board to always be able to return you to RC control as a safety measure. * The settings we will be testing in is * 1. Auto * 3. FBWA * 4. FBWA * 6. MANUAL * If you would like to test your plane with other settings, some options include: * MANUAL- Regular RC control, no stabilization. * STABILIZE- RC control with stabilization; let go of the sticks and it will level. * FLY BY WIRE_A- The autopilot will hold the roll and pitch specified by the control sticks. Throttle is manually controlled, but is constrained by the THR_MIN and THR_MAX settings. Note that THR_MIN is 0 by default, but if you raise it in the parameter settings, the throttle will rise to at least that value when FBA-A is invoked, even on the ground (so be careful!). The plane will not roll past the limits set in the configuration of the autopilot. Great for new pilots learning to fly. * FLY BY WIRE_B- Requires airspeed sensor. The autopilot will hold the roll specified by the control sticks. Pitch input from the radio is converted to altitude error, which the autopilot will try and adjust to. Throttle is controlled by autopilot. This is the perfect mode to test your autopilot as your radio input is substituted for the navigation controls. If no airpseed sensor is present, this will default to FBW-A. * AUTO- Aircraft will follow GPS waypoints set by configuration utility. (You can also "nudge" the aircraft manually in this mode) * RTL- Aircraft will return to launch point and circle there until manual control is regained. You can also "nudge" the aircraft manually in this mode. * LOITER- Aircraft will circle in current position. (You can also "nudge" the aircraft manually in this mode) * TAKEOFF- Auto Takeoff is set by the mission control scripting only. Throttle is manual (it respects the limits of the autopilot settings so if you have 65% throttle as the max, it will not go above 65%.) Once the plane is moving faster than a few m/s it will lock onto a heading and hold that heading until the desired altitude is reached. * LAND- Auto Land is set by the mission control scripting only. Throttle is controlled by the autopilot. After getting closer than 30 meters, the course will lock to the current heading. Flare, throttle, flaps, gear, and other events can be scripted based on distance to landing point. * Battery Monitor * The battery monitor will measure the voltage of the battery during flight and display this data on the “Flight Data” screen. * Fill in settings as shown below: * Monitor- 4: Voltage and Current * Sensor- 4: 3DR Power Module * APM Ver- 2: APM 5+ - 3DR Power Module * Battery Capacity- 2100 mAh

* Airspeed Sensor * The airspeed sensor will measure the airspeed during flight and display this data on the “Flight Data” screen as well as calibrate other settings. * Check “Enable” Box * Check “Use Airspeed” Box * Airspeed Pin: APM 2 Analog Pin 0

* Congratulations! Your hardware configuration is now complete. * Now if you switch to the Flight Data tab with MAVLink connected, you will see the artificial horizon moving with the board.

Flight Data Screen * The home screen located under the “Flight Data” tab. * This screen will provide a quick view into important flight parameters

The Actions Tab (2nd Tab) also has important properties: * Restart Mission- this button must be pressed when the mission is being restarted. * Set Home Alt- where you determine what location you want the computer to consider as “zero altitude.” * Clear Track- This will clear the tracking of the flight path from a previous flight so that a new flight can be more easily viewed.

Tuning your Airframe * The “Config/Tuning” is the destination for tuning your plane. * Tuning your airplane is a very important step in creating a successful mission. When performed correctly, you will have exponentially more control over your vehicle. Tuning varies based on individual design and is perfected through testing and observation.
Basic Tuning * Basic Tuning should be performed on every airplane to optimize performance.

* PID’s (Proportional, Integral & Differential) * These are all parameters that will adjust the type and magnitude of software response to the planes errors and inefficiencies while flying. * “P” recalculates a response in the airplane based on the present error. “I” uses an accumulation of past errors, and “D” is a prediction of future errors based on current rate of change * We will rarely adjust the I or D settings. * As P is the proportional reaction, it will tell the computer to amplify or reduce a response by whatever factor is entered. * Inputting a “1” is allowing the system to perform as it is. * Inputting a “0” would yield no reaction. * Inputting a number less than 1 would subdue a reaction. If the plane looks as if it is moving too quickly (twitching) in roll from a command, then it is advisable to lower this number below 1. * Inputting a number greater than 1 would increase a reaction. If the plane seems to respond too weakly to commands, it is advisable to test higher numbers. * Tuning the plane to an optimal P gain is very important and varies greatly between designs. If the proportional gain is too low, the control action may be too small when responding to system disturbances, and if the proportional gain is too high, the system can become unstable. The only way to perfect these numbers is through diligent testing on individual designs. * Period * Similar to the P control discussed above, if the entire turning system is either responding too slowly or quickly, then the Period (listed in L1 Control- Turn Control) should be adjusted. * Decreasing this number will shorten the time period of how quickly the data loop operates and the plane will respond more quickly. * Increasing this number will decrease the responsiveness. * This number will also vary based on individual design and can be determined through in air testing. * Navigation Angles * Bank Max, Pitch Max and Pitch Min * This numbers will limit the plane to a certain range the software will allow the plane to either bank or pitch to complete a command. * If the plane seems to be having issues completing a reasonable turn, then increasing the bank angle may allow the plane to maneuver further to complete the action. However increasing these angles too much will cause instability. * Throttle * You are able to set at what percentage of throttle you would like your plane to cruise at and what its minimum and maximum will be. * The cruise and maximum will be determined through testing, but minimum should be set at 0. * Airspeed * Similar to throttle, you are able to set parameters for what speed you would aim to cruise at, as well as the minimum and maximum speed the fly by wire mode should operate within. * General Notes on Parameters * More advanced parameters (which are not always necessary) are on the “Advanced Params” screen under the “Config/ Tuning” tab. * After deciding which parameters will be tested, click the “Write Params” button located on the bottom of the screen. This will upload the data to you APM board and must be done when any change is made to this page.
Recommended Process for Tuning When Starting with New Plane

1. Fly in manual mode just to make sure everything is hooked up right 2. On the ground check Stabilization mode. If you bank the plane, you should see the ailerons respond to return the wings level. If you pitch the plane you should see the elevator respond to correct the pitch. If you are using 4 channel control the rudder should respond in the same direction as the ailerons. 3. Fly in Stabilization mode and verify that the autopilot will indeed return the aircraft to level flight from a banked or pitched condition. If the aircraft oscillates in pitch or roll severely, reduce the P gains. 4. Fly in Fly-By-Wire A (FBW-A) mode, checking both pitch and roll. The plane should hold the attitude you tell it. The transmitter stick position directly sets the bank and pitch angles. Start by flying straight and level, and then push the stick all the way to one side. The plane should bank to 45 degrees or so and maintain that bank. Decrease SERVO_ROLL_P if it's unstable and swinging back and forth; increase it if it's too slow. Repeat with pitch, up and down. 5. If things still are not quite right in FBW, look at your settings for LIM_ROLL_CD, LIM_PITCH_MAX and LIM_PITCH_MIN (the units of all of them are in hundredths of a degree). If you move the stick to the extreme right the plane should go into a bank of angle LIM_ROLL_CD (and stay there). Does it do this? If it gets there slowly increase the roll servo P gain. If it oscillates in roll decrease the servo gain. Work on pitch in a similar manner. The goal is for the plane to respond in pitch and roll in a crisp manner to your stick inputs. Work on this without worrying about the other gains until when you flick the stick and hold it to the side the plane will respond crisply and as quickly as in manual flight. You will likely only need the P gain, but some airframes will need I gain to hold the desired bank angle well without steady state error. 6. Now, staying in Fly-By-Wire, again throw the stick all the way over and watch to see if it maintains altitude. If it descends increase PITCH_COMP by .10. You should be able to hold a sustained HEAD_MAX bank turn so you neither gain nor lose altitude. 7. Now try RTL mode. The aircraft should come back to you. If you set the SERVO_ROLL_P correctly in the previous step, the aircraft should navigate pretty well. But if it's flying away, increase NAV_ROLL_P by 25%. If, on the other hand, the aircraft comes back to you but weaves and snakes, decrease NAV_ROLL_P. If that's not enough, increase XTRACK_GAIN. 8. Finally, it's worth noting that if you change your cruising speed significantly you may need to re-tune your gains. So if you've been testing at 1/3 throttle but want to fly at full throttle, you may find that issues return. It's best to test at about the throttle setting you want to normally fly at.
Advice for Tuning: Poor Waypoint Reaction * If you have your plane stabilized well, but it seems to "snake" a lot between waypoints or back to launch, or even worse it's easily blown downwind and can't make it to waypoints at all. What to do? * The above guidelines should help you, but here are some specific tips: 1. The best way to test is with a four-waypoint box pattern in a large enough area so that the aircraft has enough room to show it's pattern, but not so big that you can't switch it back into manual and bring it back if things aren't going right. 2. The first thing to check is your SERVO_ROLL_P. Did you do that 45-degree fly-by-wire (FBW) test? Odds are that if your plane isn't navigating well you don't have enough servo authority and you'll need to turn that value up. But the only way to be sure is to do the FBW test. 3. If you've got SERVO_ROLL_P dialed in well, check NAV_ROLL_P on that four-waypoint course. If the plane lacks navigation authority, increase it; if it's snaking, decrease it. 4. That should get you pretty decent waypoint following. The last thing to do to really get it to follow your paths well is to play with the Crosstrack gain. What it does is bring the aircraft back to the line between waypoints, rather than just flying directly towards the next waypoint. This diagram shows what crosstrack error correction does:

With the gain at 0, you should get the red line. As you turn the gain up higher (100 is the default), you should get something closer to the blue line. If the aircraft weaves when following a track, decrease XTRACK_GAIN from the default 100. The faster the aircraft flies, the less this number should be. In order to ignore tracks completely, just navigate line of sight from way point to way point, decrease to zero, then any remaining snaking will be influenced entirely by Nav_Roll and Roll.

Mission Planning * To create a mission, open the “Flight Planner” tab. * Once a zoomed in image of the flying field is displayed on the screen, you are ready to create your Waypoints. * To create waypoints, you can either click in a pattern on the displayed map or click “Add Below.” Using the commands along top and side of the list of waypoints, you can rearrange the order, add and delete them. To move the geographical location of a point, just click and drag on the image of the map. * In the dropdown menus on each row, select the command you want that waypoint to perform. The column heading will change to show you what data that command requires. * There many different options for commands including:Takeoff, Do_Jump, Return to land, and many more. * A WP radius and default altitude should always be set along the top of the commands. * You may vary altitude for each waypoint individually if desired. Altitude is relative to your launch altitude, so if you set 100m, for example, it will fly 100m above wherever the home altitude is set at (Reminder, home altitude can be re-set from “Flight Data” screen.) * Note that if the "Absolute Alt" box is checked, the altitude used will be altitude above sea level, NOT altitude above your launch position. If that box is unchecked, ALT will be relative altitude, so 100m will be 100m above your "home" altitude. * An example of a basic pattern is shown below:

* Once a desired flight path is created, you must load the waypoints onto the APM board by clicking “Write Params.” * This has to be done when any change occurs. * Make sure to save! * You can save multiple mission files to your local hard drive by selecting "Save WP File" or read in files with "Load WP File" in the right-click menu:

Recording and Playing Back Missions * If you are using wireless telemetry and have connected to APM via the Mission Planner, your flight data will automatically recorded as a "tlog" file in the Mission Planner's logs folder. * You can load and replay any one and convert any log to a KMZ file that can be displayed in Google Earth by clicking on the KMZ button. That file can also be found in the logs folder.

* While the log is replaying, you can analyze the data by clicking on the "Tuning" checkbox under the map display in the Flight Data tab. It will show the recorded data changing as the flight progresses. You can double click on the data legend to bring up a box that will let you choose which data fields are graphed, as shown here:

First-time Flying Checklist
Here are the basics to check at the field:
Ground Calibration * Set your transmitter mode switch to "Manual". This is a safe mode in which to start up the system. When you power on your board at the field, you should leave the plane motionless on the ground as level as possible (in flight position; so if you have a tail-dragger elevate the tail) until the three colored LEDs stop flashing (about 30 seconds). That means that the gyros have been calibrated and the plane is ready to fly (assuming you also already have GPS lock). If your plane is a tail-dragger, you should prop up the tail to level flying attitude during calibration. * After the ground start completes you should wait for GPS lock before flying. If you do not wait for GPS lock the home location will not be set correctly, and the barometric altimeter calibration will be incorrect. It should take less than two minutes to get lock. * BEFORE EVERY FLIGHT: Before you take off, hold your aircraft in your hands and switch to FBW-A mode, then pitch and tilt the plane it to confirm that the control surfaces move the correct way to return it to level flight. This will ensure that you haven't accidentally reversed a channel. Failing to do this is the #1 cause of crashes.
Launching in Auto Mode * APM: Plane can automatically launch a a wide range of aircraft types. The instructions below will teach you how to setup your mission to support automatic takeoff. * Basic Instructions * The basic idea of automatic takeoff is for the autopilot to set the throttle to maximum and climb until a designated altitude is reached. To cause the plane to execute a takeoff, add a NAV_TAKEOFF command to your mission, usually as the first command. There are two parameters to this command – the minimum pitch, and the takeoff altitude. The minimum pitch controls how steeply the aircraft will climb during the takeoff. A value of between 10 and 15 degrees is recommended for most aircraft. The takeoff altitude controls the altitude above home at which the takeoff is considered complete. Make sure that this is high enough that the aircraft can safely turn after takeoff. An altitude of 40 meters is good for a wide range of aircraft. * During takeoff the wings will be held level to within LEVEL_ROLL_LIMIT degrees. This prevents a sharp roll from causing the wings to hit the runway for ground takeoffs. * Note that the takeoff direction is set from the direction the plane is pointing when the automatic takeoff command is started. So you need to point the plane in the right direction, then switch to AUTO mode. During the first stage of the takeoff the autopilot will use the gyroscope as the principal mechanism for keeping the aircraft flying straight. After sufficient speed for a good GPS heading is reached the aircraft will switch to using the GPS ground track which allows it to account for a cross-wind. * NOTE: You should try to launch into the wind whenever possible. * Hand Launching * A hand launch is a common method to launch smaller aircraft, such as foam gliders. APM:Plane has a number of parameters that control how a hand launch is done. If you are planning to hand launch your aircraft in AUTO mode then please look through these options carefully. * The keys to a good hand launch are: * If the propeller is behind your hand during launch then ensuring that the motor does not start until it is past your hand * Ensuring that the aircraft does not try to climb out too steeply * The main parameters that control the hand launch are: * TKOFF_THR_MINACC * TKOFF_THR_DELAY * TKOFF_THR_MINSPD * TECS_PITCH_MAX * When the auto takeoff mission command starts (usually by switching to AUTO mode) the autopilot starts in “throttle suppressed” mode. The throttle will not start until the conditions set by the TKOFF_THR_* parameters met. * The TKOFF_THR_MINACC parameter controls the minimum forward acceleration of the aircraft before the throttle will engage. The forward acceleration comes from the throwing action of your arm as you launch the aircraft. You need to set this value high enough that the motor won’t start automatically when you are carrying the aircraft normally, but low enough that you can reliably trigger the acceleration with a normal throwing action. A value of around 15 m/s/s is good for most aircraft. * The TKOFF_THR_DELAY parameter is a delay in 1/10 of a second units to hold off starting the motor after the minimum acceleration is reached. This is meant to ensure that the propeller is past your hand before the motor starts. A value of at least 2 (which is 0.2 seconds) is recommended for a hand launch. * The TKOFF_THR_MINSPD parameter is a minimum ground speed (as measured by the GPS) before the motor starts. This is an additional safety measure to ensure the aircraft is out of your hand before the motor starts. A value of 4m/s is recommended for a hand launch. * Note that if your aircraft is a “tractor” type with the motor at the front then you may want to set TKOFF_THR_DELAY and TKOFF_THR_MINSPD to zero, or use lower values. * The final parameter you should think about is the TECS_PITCH_MAX parameter. That controls the maximum pitch which the autopilot will demand in auto flight. When set to a non-zero value this replaces the LIM_PITCH_CD parameter for all auto-throttle flight modes. Setting this parameter to a value which is small enough to ensure the aircraft can climb reliably at full throttle will make takeoff much more reliable. A value of 20 is good for most aircraft.