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Meet the Eggtimer Proton
The Eggtimer Proton is an advanced hobby rocketry flight computer with a barometric pressure
sensor, 120G accelerometer, and six high-current output channels. Its job is to properly deploy
your parachutes and bring your high-powered rocket safely to the ground, and to record flight
information for later analysis. In addition, it can handle other events such as airstarting motors
or just about any other event that you can come up with. Each channel can be programmed
independently for whatever function you need. In addition, channels can be "clustered" so that a
single event triggers multiple channels, perfect for cluster airstarts. Channels can be triggered by
a number of different events for an almost unlimited combination of scenarios.
It's nice to get your rocket down in one piece, but it's also nice to know how the flight went.
The Proton can record your last 14 flights, and you can easily view and/or download both
summary statistical information and detailed time vs. event information. The detail output
format is a standard .csv file, which can be imported into virtually any data analysis program.
What makes the Proton different from most other flight computers is that it has a WiFi interface.
Instead of using switches, jumpers, or a data cable to your laptop to program it, you simply
connect to it with your phone, tablet, or computer using WiFi and a browser like Safari, Firefox,
Internet Explorer, or Chrome. You remotely arm it at the pad using your handheld device too, so
for many applications you do not need a mechanical switch... it won't turn on until you tell it to.
Flight data is downloaded to your handheld device using WiFi, and with the installation of an
appropriate spreadsheet or other data analysis program you can actually get a flight graph within
seconds of recovering your rocket.
Since one of the tenants of successful electronic deployment is ground testing, the Proton
incorporates a ground-test feature so that you can check YOUR battery with YOUR igniters to
make sure that they are compatible and will work in flight. This is done remotely over WiFi, so
you can even test with "live" pyro charges, standing up to 100' away from your rocket.
The output channels are capable of triggering just about any load that you're likely to encounter,
we've even fired a medium-current Estes igniter with it using a 2S/7.4V LiPo. You can set the
output on-time from 1-9 seconds, so it's ideal for use with a hot-wire non-pyro deployment.
There's a separate battery input for the deployment circuitry, so you can optionally use a second
battery on the deployment outputs that 100% guarantees that a deployment glitch will not cause
your Proton to "brownout" due to low voltage. Each channel is overload protected so they can't
be blown out with an accidental short.
You can also use standard PWM hobby servos with the Proton, for non-pyro deployments. This
makes it ideal for use by TARC teams that want to experiment with electronic deployment but
can't use pyrotechnics, or for flights over 30,000' in which pyro charges may not be effective.
In addition to deployment functions, the Proton can also be used to "airstart" additional motors in
flight, either for "strap on" boosters or for starting a second stage motor. It works as a timer that
starts at launch, and is qualified by breakwire support, velocity-at-time, and/or altitude at time.
There is also a Barometric-Altitude-Deviation calculation that won't fire your airstart motor if
the rocket is moving off-axis. This helps ensure that your second stage won't light unless your
rocket is going "up".
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