Competition | 2023-2024 Aerial Evolution of Canada Student Competition | ||||||
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Team | Waterloo Aerial Robotics Group | ||||||
Technical Director | |||||||
Version | Document Version
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On this page |
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Min | Recc/Avg | Max | |
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Propeller Diameter (in) | 20 | 22 | 24 |
Battery Voltage (v) | 36 | - | 50.4 |
Takeoff Weight | 4.5 | < | 8 |
Thrust (kg) | ~16 | ||
Flight time (min) | 30 | TBD (40?) | |
Wind Lim. (kt) | < 20 | TBD (< 60) | |
Altitude (m) | < 120 | 200 | |
Horizontal Pos Accuracy (cm) | +/- 2 | +/-30 | +/- 200 |
Vertical Pos Accuracy (cm) | +/- 2 | +/- 15 | +/- 30 |
Usable Range (km) | 1 | 10 | inf w/LTE |
Airframe
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Pegasus is an X-frame configuration and motor arms attached directly to a straight aluminum block. Here are some of the key notes:
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Motors are mounted on 3d printed mounts with a <pattern> (insert a photo if you can).
Propulsion
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< insert schematic here >
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Telemetry wires shall be connected to a uart port, in the case of a bidirectional dshot failure. This is significantly slower than bidirectional dshot but offers us a failsafe and backup.
Power Distribution
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On Pegasus, “power distribution” refers to all elements that affect and interact with power before it is distributed to individual components. Typically, this includes:
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Pegasus officially supports 4, and 6 battery configurations. Physically 8 batteries will fit with a light enough payload.
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These batteries are cross-connected from each other, meaning that the only difference between a 4 and 6 battery connection is the NC of one pair. These should be labelled or colour coded<Image / harnessing>
Below shows the two different battery configurations we can fly. Pairs of 6S battery cells are connected in series and terminated with an XT90. The harnesses below show how the batteries are attached and how removing harness 3 and the cells with it bring the drone into its 4 cell configuration.
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XT90 standard across the board, but the maximum peak current draw from all 4 motors is anticipated to be around 90Amps. Any individual motor will not draw more than 23 amps at a time, not including the path.
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The pixhawk also supports two concurrent power monitors. We are using 1 power monitor and 1 BEC with NC’s on the remaining pins for better redundancy under thermal limit.
Flight Control System
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Pegasus will operate using an ardupilot software stack. As of Fall 2023 Pegasus runs software revision 4.4.0, as this brings necessary changes for digital power monitoring and bidirectional dshot.
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Accelerometer calibration does not need to be done more than the first time you did setup, or if there is significant concern about the health of the system.
RF + Peripherals
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There are a number of external devices on the drone. Autonomy is largely responsible for additional compute, while Electrical is largely responsible for RF
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