As we continue to move forward with this class we are getting closer to the fun part, flying the actual planes! Although we have all been putting time in on the flight simulator's, and may think that we can just take a plane out and fly it right now, there are a few things we need to do before actual take off. Before every flight we have a pre-flight check list. This check list is designed to allow us to check every single piece of the plane to allow it to fly safely and do the things we want it to do. Along with the pre-flight check list, we also have what's called mission planning. When dealing with mission planning we can upload a flight path from the mission planning server on our computer to allow for our plane to fly exact missions that we so plan. These missions that we upload to our UAS will have the UAS flying on autopilot. If there is a time when we need to take over for safety measures, we can do so.
The mission planning server looks a lot like ArcMap with a satellite imagery overlay. You can reference the area you are going to be flying along with the surrounding area to devise a good mission plan that gives you adequate area to take off and land as well. There are purple dots on the screen to mark no fly zones. It is advised to stay well away from this area, you don't want to be contacted by the FFA for flying to close to a no fly zone. In the mission planning controls we are able to map an area we want the UAS to fly. We can have all sorts of patterns, boxes, squares, circles, random lines, etc. Now when dealing with an area that we want to have photographed in our mission, we can set how many pictures/ second, the angle of the pattern depending on wind, the grid and overlay of our pictures, down to the exact camera that we are going to be using. It is critical to have a good mission plan in store when you want to go out and fly. By doing this you can assure that you are going to be safe along with ethical when you are flying.
After we have made our mission planning inside on the computer, we are ready to go outside and do our pre-flight checks. There are many different items on the UAS and computer that we need to go over so we have created a check list to ensure that we don't miss any steps that allows for us to have a safe and successful flight. This has now turned into a three person job with a pilot, spotter, and computer monitor. The first step is hooking up your communications from the computer to the modem. The modem allows for the computer to send the mission to the UAS allowing it to fly the mission we so desire. Typically the modem is attached to a wonder stick. A wonder stick allows for the modem to be raised into the air allowing for a better connection with the UAS. The first section of the check list now deals with flight prepping.
We want to record the date, time, platform, and weather. When collecting the weather information we want to record the temperature, but most importantly the wind and wind direction. This will tell us wether it is safe to fly or not. The next ten steps of the flight prep have to deal with looking on the UAS. We want to make sure all the connections from electrical, frame, motor, props, batteries, and antennae are all tightly secure and have no damages. It is smart to use a small screwdriver to just go over all of these areas to make sure nothing is lose or wobbling. We want to inspect the props for cracks. Even a minor crack could cause for a failure in a prop which would make it dangerous to fly incase of a crash. When balancing the battery, we want to pick the UAS with or finger tips allowing for it to balance evenly. If the UAS is not balanced evenly, it can cause for it to fly out of control or for it to not be safe. It is important to have your battery balanced in the middle of your UAS. After completing all of these checks on the UAS you can now turn your TX transmitter on, while making sure your throttle joy stick is in the off position.
The next steps deal with powering up your UAS and mission plan. When you have completed a step on the check list we put an "x" through it.
We want to double check that we have the modem properly connected to the computer. Typically when connecting your modem to the computer you want to use the blue ports on the side of your computer not the white ones. The blue ports are typically faster and allow for a better connection. We now can connect our UAS to the base station. We want to see how much battery is on our computer as well. Imagine flying your UAS on a mission then your computer dies, this could lead to a bad ending to your mission. The next step is very important. We need to check the battery voltage on our UAS. If the voltage is below a 12 we need to use a different battery. We also need to check the voltage on our TX transmitters. We also want this as close to maximum as possible, again imagine flying then your controls cut out because you forgot to check your TX battery. This would cause it to be very hard to land your UAS. When checking for satellites, you can find this in the lower left hand corner in red in your mission plan on your computer. A great number of satellites to have is over, while it is advised to not fly with less then six satellites. We now want to upload our mission to our UAS while making sure the mission area is secure. You don't want to be flying over a playground taking pictures while an elementary school is outside playing. This comes back to flying ethics and being safe. If you are questioning yourself if it's safe to fly, more then likely it is not.
Now that we have gone through all of the pre-flight check list it is time to start the takeoff sequence. It can't be stressed enough that when you are the pilot you concentrate on following the UAS in the sky along with the spotter. You need to watch for obstructions that could get in the way, or a shift in wind direction, and even pedestrians on the ground. While the pilot and spotter are concentrated with the flying aspect of the UAS the communications person needs to stay focused on the computer and mission plan. They need to watch to see if the satellites stay connected, follow the path of the UAS on the computer screen, and checking to make sure the mission plan is being carried out. At any time the communications realizes there is a problem with the plan they need to tell the pilot and spotter allowing for the mission to be aborted.
The most important item when dealing with the takeoff is that the area is secure and clear of spectators. You don't want to be taxing down the runway when a person is walking down the same runway. This could lead to damages to the person and your UAS. You want to make sure all spectators are clear. You want your TX transmitter throttle all the way back. You can now flip the switch on your platform allowing for it to arm. When you do this you typically will hear beeping which tells you the platform is armed. You can now deactivate your kill switch. Once you arm your TX you are in control and ready to lift your UAS off the ground. Since we were using a multicopter for this, we want to raise it off the ground and have it loiter or hover in position. When your UAS is loitering you want to talk to the communications post. You want to check again for your satellite signals, weather, and waypoints on your mission. Once your communications checked out you are ready to bring your UAS up to the designated height and switch it to autopilot. Once you flip the switch to auto, your UAS will take off and fly the mission that you uploaded. MAke sure the pilot and spotter have eyes on the UAS while the communication post continues to talk and double check the satellites while the mission is being carried out. Once the mission is complete and you are ready to bring the UAS down, again check the area for spectators. You don't want to be bringing down your UAS and someone decides to walk under it while it has spinning blades and is landing, this could turn messy.
Upon being on the ground you are ready for the post land check list. You want to disconnect from the base station while powering down your UAS. Once the UAS is secure and motor functions are off with the kill switch activated, you want to check again your entire platform to see if any wires, or frame connections have become loose during the mission. I would retighten everything right away, this allows for you to have a baseline when you decide to carry out another mission. You want to disconnect your battery so you can charge it and turn your TX transmitter off. You have now successfully completed your mission.
The final steps of this check list deal with transferring your pictures to your computer and analyzing the data. We have not carried out this step yet individually, but will in future missions. This is a checklist that has been created from many missions. It is never perfect and always has room to add. By changing items on this check list or adding items, you are assuring that you are acting as safe as possible when carrying out the mission. It's always safety first. The safety of you, pedestrians and spectators around your, and the surrounding area. It doesn't matter if your UAS crashes or you have to abort a mission as long as you stay safe in the field.
No comments:
Post a Comment