BPS Signal R2 Tuning Instructions

Welcome to the tuning instructions! These procedures will help your Thrust Vector
Controlled rocket fly straight and stable. Rocket tuning takes place in the Signal app on
an iPhone or Android device. Turn on Signal R2, open the app, and connect to your
Signal R2 flight computer.
This process can take several minutes, it may be helpful to turn off the buzzer in the
System Prefs section. Then tap the "Tuning" button to begin.
If you have questions or find something confusing, please email support@bps.space -
TVC rockets can be tricky, and BPS is here to help!

1. Weigh the fully loaded rocket

a. With the motor loaded, and parachutes packed, place the rocket on a scale. Ideally, its
mass will stay the same between now and launch.
b. Using the Signal app, enter this value, in kilograms, in the "Loaded Mass" text box

2. Find and mark the CM (center of mass)

a. Try to balance the rocket sideways on your finger. Once the rocket is balanced, mark the
location of your finger on the rocket. A piece of tape or a rubber band will work.

3. Measure the distance between the CM and Thrust Vectoring mount

a. Find the distance between the two and record it in your notes. We're measuring the
distance between the CM and the TVC-airframe screws - the point at which the TVC
mount is connected to the airframe.
b. Enter this distance, in meters, in the "COM-TVC" text box
4. Create two equidistant "hang points" from the CM
a. Here we're prepping the rocket to be hung sideways from two strings, and we need to
mark where the attachment points will be
b. Each string should be at least 15 centimeters away from the CM, and both of their
distances from the CM should be the same
c. Mark the points with a piece of tape or rubber band, just like the CM
d. Enter this distance, in meters, in the "String-COM" text box
Copyright © 2018 Barnard Propulsion Systems, LLC.
Rocket Tuning Instructions
For use with Signal R2, running
SignalSoft 1.5.6, with R2 hardware.
Version 1.3, July 12, 2018
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