June 11, 2023 Flight Test

Make sure to update the Title following the format “Jan 01, 2020 Flight Test”

 Flight Preparation

Requested by:

@Anthony Luo

Required Sub-teams

Mech
Electrical
EFS
CV
Operation
Sys-Int

Requested Date

Jan 25, 2023

Location and Time

Location: WREST RC Time: June 11, specific time TBD

Summary & Goals

Takek off Vanny?

Approved?

Yes / Pending / No

 Required Persons During Test

Name

Phone #

Role

Reason

Name

Phone #

Role

Reason

 @Anthony Luo

 

Flight Test Lead

  • Creating documentation

  • Booking the test flight

  • Creating a thread in #flight-staging

 @Anthony Luo @Megan Spee

 

 Pilot in Command

  • Aircraft preparation

  • Filling out documentation

@Conall Kingshott

 

Safety

  • Making sure everyone is safe

  • Bringing Med kit

 Other Attendees

Name

Role

Name

Role

@Nathan Green

 

 

 

Drivers & Seat Arrangement

Driver

Vehicle Type

Passenger

Driver

Vehicle Type

Passenger

@Anthony Luo

RAV 4 SDC Vehicle

 

 

 

 

 

 

 

 

 Success criteria

Tests

Success Criteria

Requirements

Outcome

Tests

Success Criteria

Requirements

Outcome

Testing Timeline

Date/Time

Action

Date/Time

Action

June 09 & 10

Pre-flight Preparation

TBD depending on Motorsport’s timeline on Sunday.

Following times assume morning.

8:00

Required persons for preflight preparation show up at bay, approx 8 am

Flight test lead briefly assign task for preparation work

9:00

Flight brief from flight test lead

9:15

Loading onto the Car

Take your water bottle with you. Go washroom before we leave!

9:30

Drive to the test ground

10:00

Flight Testing

12:00

Debrief

Aircraft Incident Procedures

Incident

Procedure

Incident

Procedure

Crash

Outline the procedure for who will go to handle the aircraft in the event of a crash, what should be done, were emergency equipment is, etc.

Flyaway

Outline the procedure for flyaways. List relevant contact information for local authorities and plans of action to recover control of the aircraft

Configuration Error

Outline steps to take in the event of a configuration issue with the aircraft

Injury

 

Property Damage

 

Week-Before To-Do List

Drone Registration

Drone Registration Number:

Flight test location booked
Pilot scheduled
Test Plan (What we are testing)
This should also include the flight path where applicable
Subteam action items (for flight readiness)
Transportation logistics finalized
Booking SDC vehicles
Assigning drivers
Renting any needed equipment (trailer? generator? etc.)

Day-Before To-Do List

SDC Vehicle key collected (if required)
Batteries Planned for (DON'T LEAVE CHARGING OVERNIGHT)
On-site kit together
Airfame assembled
ESCs/flight controller wired
Radio equipment tested
Motors tested
Wiring secured (Harnessing)
End-to-end test (neglecting props)
Check the center of gravity
All components not on the airframe that are required should be in the flight box (e.g. props & prop nuts)
Airframe payload
Spare parts
Flight Code Flashed
Ground station Software updated

Pre-Departure Checklist

Pre-flight Safety Checklist

Post-Flight Checklist

Item

Owner

Item

Owner

ALL MEMBERS PRESENT

 

 

Flight Debrief

In total, multiple flights were performed. Basic functions such as flight modes, RTL, auto-land, and failsafes were tested.

Flight set #1 (basic function + flight modes)

The first set of batteries was put in for basic functionality check of the drone.

Voltage of first set of batteries on the first set of initial flights

The drone was flown in three different flight modes, in the following order:

  • Stabilize, Megan

  • Stabilize, Anni

  • AltHold, Megan

  • Loiter, Megan

Flight set #2 (RC, GCS failsafe + RTL)

The first set of batteries was then used for testing RTL, RC Failsafe, and GCS Failsafe.

Voltage of first set of batteries on second set of flights

The order of testing was as follows:

  • Stabilized takeoff + flyout → RTL (from short range)

  • Loiter takeoff + flyout → Transmitter poweroff (with RC link through RFD900’s) → Smart RTL

  • Loiter takeoff + flyout → RFD900 poweroff (RC Link on drone directly). → Loiter landing.

    • “Continue if in pilot controlled modes on GCS failsafe” was checked.

  • Loiter takeoff + flyout → RFD900 poweroff (RC Link on drone directly) → RTL

    • “Continue if in pilot controlled modes on GCS failsafe” now unchecked.

  • Testing RTL mode actions on altitude

    • first test ensures loiter will climb to RTL altitude

    • second test ensures loiter will only descend at landing time.

Flight Set #3 (testing autoland, position hold)

A new set of batteries were used to test position hold, RTL, and autoland accuracy.

  • GPS-Only loiter accuracy was observed to be within +/-30cm when left at no stick input (very good).

  • RTL accuracy evaluated to be roughly +/-50cm

 

Flight Test Post Mortem

  • Vanny Flew

  • Pitch/Roll tune looks good

  • Total flight time for 50% battery capacity is around

  • Altitude hold incredibly consistent

  • Yaw control is lacking (almost as bad as cornflakes).

    • Megan doesn’t think it was as bad. Maybe 1/2 as bad as cornflakes. Spun it around a lot and it responded in a predictable way.

Logs here: https://uofwaterloo-my.sharepoint.com/:f:/g/personal/uwarg_uwaterloo_ca/EiGR3sG4uM5Gr15i40EfLP8Bzvi_Wu2oMfD9rSTNAVL9-g?e=ehv0dz

Photos here: https://uofwaterloo-my.sharepoint.com/:f:/g/personal/uwarg_uwaterloo_ca/EtUtjlQe_kpPuI0S8IbM6YoB5-gikldpSNRogi2iGjDLoQ?e=bCaPyL

Flight Characteristics

Since this is the maiden flight of Vanny for a while, I’d like to go over some flight characteristics.

Pitch/Roll Control

Pitch/Roll control was good, however the drone was slightly sluggish to respond and the maximum roll/pitch angle could be higher (I think).

In the above image, you can see that there is some overshoot and oscillation on roll, which you can more clearly see on a zoomed in crop of the last few half-impulses before returning to center:

The same can be observed on the pitch axis:

Note that during the entire impulse test, the drone was able to maintain altitude fairly well, although it’s difficult to tell since the drone is correcting for it’s own altitude during flight. This will be discussed more when I talk about altitude hold.

Yaw Control

Yaw control seems to be one of the weaker items on our drone . Not sure if this is due to poor tuning or throttle output saturation (unlikely). In general, the drone would carry a lot of momentum after letting go of the yaw input, and would tend to overshoot / continue with yawing after letting go of the stick (often leading to backstick).

I’m not sure what might cause this - but I would like to compare results after running auto-tune on yaw.

Altitude Control

Altitude control was excellent, even without a rangefinder. The GPS + Barometer + IMU system on the higher end pixhawk is really doing wonders to keep the drone stable.

You can see pretty clearly that our altitude and desired altitude are quite close to each other, in all guided flight modes. There is some measured “oscillation”, but this is very small. Any actual difference in altitude during flight would have come from errors in measuring / calculating altitude from EK3.

It is worth noting that the hover throttle was fairly consistent throughout all flights, with the individual motor outputs being around 1500 us. Angle boost was also fairly minimal, but present and effective at helping the drone maintain hover:

Red = Front Right

Green = Back Left

Blue = Front Left

Orange = Back Right

In general, it’s hard to determine if one side of the drone is significantly more imbalanced than the other, but you can clearly tell that the hover throttle for the drone is around half (i’m not sure if there’s better measurements that I can make).

Position Accuracy

In general, position accuracy was great (considering this is one non-rtk gps). We were within +/-50cm doing multiple takeoffs and RTL’s, and the drone logs show that desired position and actual position correspond quite well. In general, this tells us that any deviation we see in position would come from measurement inaccuracies from the sensors themselves.

RCA for Red Items

Create a RCA and keep it as a child page.

Action Items

Other Resources

Booking WRESTRC Field

WRESTRC