RPM LIMITER

The Igniter Class uses an RPM Limiter to cap the speed of your motors to the ideal racing speed. Installing this RPM Limiter is necessary for your Igniters to be made legal. This is how you do it:

IMPORTANT NOTE

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BEFORE YOU START

It is a good idea to start with a good CLI dump for your board from Betaflight 4.4.2, which may or may not be from Kaack. This will drastically speed up flash time, but it isn't strictly necessary.

FLASHING THE SL RPM LIMITER

We are now using a locked hex, which requires you to flash a new version of Betaflight.

WRITTEN STEPS

For those familiar with Betaflight, this may cover all the information you need. If you need more help, watch the video above.

Step 1 (Optional)

Get a dump of your current firmware (if you have your preferred settings/rates already in it).

Step 2

Flash the new hex. Use 4.4.2 Kaack Special Release and type "igniter" into the pull request/commit

Step 3 (Optional)

Put your dump in your CLI. You can ignore any errors, this step is optional anyway. All of the spec required settings are locked so if you get any errors, it's not going to affect the limiter.

Step 4

Turn on the boost bar in OSD. This is listed as "Battery Usage (Graphical Remaining)" in the OSD tab. Once you complete this step, your quad is officially spec legal.

Step 5 (Recommended)

Go to your modes tab and add Boost to a switch, This isn't necessary to be in spec, but I'd recommend doing it so you can get your boost!

Step 6 (Troubleshooting)

Just to make sure your quad works properly, there are some things you'll want to look at. First, make sure your quad has bidirectional dshot turned on in the motors tab or your quad will not be able to take off. Also make sure that your idle speed is low enough (the CLI below will take care of this) as if it's too high, it will interfere with the RPM limiter and you won't be able to take off. Make sure your CPU load is low, primarily by using DSHOT300 (in the CLI below) and using a low PID Loop Frequency in your configuration. If your CPU load is too high, your quad might act up.

If you're coming from a good flash and use the dump, none of these things should be an issue as these settings should all be in your dump.

RPM LIMITER CLI

Since we have a locked hex, there is no need to use any CLI anymore, outside of convenience. Once you flash your drone, it will have all the legal settings (except OSD). These settings can speed up the process of setting up your quad if you don't already have a dump from previous seasons.

Speed Flash CLI

set motor_pwm_protocol = DSHOT300

set yaw_motors_reversed = ON

set small_angle = 180

set dshot_idle_value = 450

save

EXTRA NOTES

This season we are using the SL implementation of the RPM Limiter. This limiter helps further equalize differences in quads while also allowing us to lock the hex to minimize cheating (accidental or intentional!)

The SL limiter also allows us to effectively limit the torque of motors. This won't really affect beginner or intermediate pilots, but it makes it much more challenging for top level pilots to achieve the fastest possible lines, raising the skill gap and making competition more interesting.

This season, we have also slightly slowed down the top speed of the quad. The reason for this was twofold: we wanted to allow for bigger boosts and we also wanted to maximize the chance of allowing higher kv motors into the spec. Unfortunately, we weren't able to allow for higher kv motors during this season. If this doesn't change by next season, we may decide to raise the top speed back up a bit. This will be based on community feedback, however, so please make sure you're in the Facebook group (click the icon below) if you'd like to potentially have a say on this matter!