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ServoChron(tm) Firmware Update (Dual servo control)

Discussion about deployment systems including altimeters, timers, air speed flaps, servo systems, and chemical reactions.
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U.S. Water Rockets2
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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by U.S. Water Rockets2 » Mon Aug 01, 2011 10:25 am

Thanks for the feedback everyone! Stay tuned for more surprises!



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by Skymeat » Tue Aug 02, 2011 8:14 pm

Great project! I've been messing with the Arduino for a couple months....I could totally work with the launch pad too, by the look of it you could pack the guts into a super tiny package if you pull the IC.. Do they have the equivalent of a wifi or cellular shield too? Would be sweet to transmit telemetry, g forces, camera feed etc back to a cell phone!



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Re: UART Diagnostics Mode

Post by tcarnahan » Fri Aug 05, 2011 7:38 am

Installation Problems:

I have been following your directions for programming the MSP430 and have obviously taken a wrong turn.

I downloaded the Elprotronics FET430 software and drivers. I ran the driver set up for my Windows 7 OS. Then installed the FET430 software. (I was going to include a screen print of what I am seeing but I don't see a way to do that in this forum).

When I selected "Open Code File", the project file I downloaded from your site did not show. I put a "*" in the window and hit enter. I was then able to see the "ServoChron_V2.00.FET430prj". I selected it and selected Open. The error message was: "This is not a valid code file". :cry:

Any suggestions?

Many thanks!



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Re: UART Diagnostics Mode

Post by U.S. Water Rockets2 » Fri Aug 05, 2011 10:39 am

tcarnahan wrote:Installation Problems:

I have been following your directions for programming the MSP430 and have obviously taken a wrong turn.

I downloaded the Elprotronics FET430 software and drivers. I ran the driver set up for my Windows 7 OS. Then installed the FET430 software. (I was going to include a screen print of what I am seeing but I don't see a way to do that in this forum).

When I selected "Open Code File", the project file I downloaded from your site did not show. I put a "*" in the window and hit enter. I was then able to see the "ServoChron_V2.00.FET430prj". I selected it and selected Open. The error message was: "This is not a valid code file". :cry:

Any suggestions?

Many thanks!
Regarding your trouble loading the firmware, the problem is that you are clicking "Load Code" when you should be clicking "Load Project"

We checked the manual and it is not vague on this:
Go to the “File” menu of the FET-Pro430 Lite application and click on “Open Project”. You will then be
presented with a file open dialog with which you will navigate to the directory where the firmware project
file is stored. You select the firmware you wish to load and click “Open”. The project file will then load into
the programming application.


Thanks for reporting the typo in the URL of the software tool. Someone else noticed this too but they said the screenshot was wrong and we looked at the screen capture and it tested out good, so we thought it was just a fluke error. Now we know where the typo really is so we can fix it. We appreciate the help!

Thanks for the feedback!



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by U.S. Water Rockets2 » Fri Aug 05, 2011 11:57 am

skymeat wrote:Do they have the equivalent of a wifi or cellular shield too? Would be sweet to transmit telemetry, g forces, camera feed etc back to a cell phone!
The MSP430G2231 chip on the LaunchPad board doesn't have enough storage RAM/Flash to handle the code needed for WiFi or Cellular, unless the shield itself contained a lot of intelligence. There probably are such shields in development or released, since the LaunchPad has really gotten a huge amount of support and is wildly popular because of the price.

Ti does make their own line of proprietary R/F chips in the MSP430 line, and they likely have something for the launchpad as well. Separate from that, they also sell a USB stick type development kit called the EZ430-RF2500 which we have used in the past.
rf2.jpg
It comes with a programmer tool that plugs into the USB port of a computer and can download the code into each of the two supplied R/F transceiver modules. TI makes their mesh network code available for free, so you can use that in your own projects. The kit contains 2 transceiver boards and a battery pack to get you going right out of the box.
ez430-rf2500.jpg
We have used the mesh network in our launch control system for our high pressure rockets. Using 2 of these kits we designed a 4 node network that we used for our world record launch attempts. One node is a PC which uses the MSP430 Application UART backchannel of the USB stick to print status messages to hyperterminal on our laptop. The status is basically the battery levels which we need to monitor because it takes several minutes to pressurize the rocket. The second node is the rocket flight controller itself, which used the ADC to measure the battery and has some FET switches to turn on the onboard electronics and camera, plus some telemetry of the altitude reading in flight.
wand.jpg
The Third node we call the "Magic Wand" and it contains the button used to activate the launch sequence. It has some LEDs built in that report the status and health (redundant indicators in case the laptop battery dies). The laptop can also initiate a launch in case the "Magic Wand" fails.

The launch sequence primarily powers up and starts the onboard camera and altimeter and indicates when the systems are running so the physical launch release can then be activated.

The 4th node in the system has one purpose. It waits for the launch detect signal to come from the rocket when it lifts off and it waits a preprogrammed time delay and then turns on an output that activates a FET switch which is connected to a remote shutter release on a camera, which is how we get high resolution stills of the rocket just after liftoff.

We have retired most of this system over the years. This is mainly due to the fact that "off the shelf" cameras like the HD 808 720P can be started up prior to pressurization and run for the entire time without running out of power or memory. Not too long ago you were lucky to get 10 minutes of video on a $50 memory card.

Some of the ideas are still used going forward, such as the altitude telemetry and battery monitor system and remote delayed camera shutter release, but we can do all this with a single transmitter in the rocket and receivers for the Laptop and camera shutter release. The magic wand doesn't need to be used anymore.

We will have to do an update on our blog describing the system in more detail. People may find it interesting.
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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by U.S. Water Rockets2 » Fri Aug 05, 2011 12:20 pm

Skymeat wrote:Great project! by the look of it you could pack the guts into a super tiny package if you pull the IC...
Our early experiments with this used the transciever on the RF2500 module. This is essentially the prototype for the ServoChron™ . This version could be activated by a time trigger or using the "magic wand" or PC commands.
rf1.jpg
The problem with this system is the cost. About 2 years ago you could get the whole system for $39 and additional RF transceivers were $9 each. The transceiver board is all you would need to control the servo, acting as a "Micro" version of the LaunchPad. But the price of the system has gone up since we purchased ours. The development tool is over $50 and the transceviers are $20 now. We didn't think many people would spend $20 on a servo controller because that price is just too high. You could pretty much buy two onboard cameras for that price. We wanted to help reach as many people as possible with the ServoChron™, and not make servo control cost prohibitive.
ServoChron_RC.jpg
The board makes a great servo controller, and if anyone were to decide to use it for a water rocket, they would still be 1/2 the size and half the cost and under 1/3 the weight of commercially available systems which don't even have an R/F transceiver. Had it been released it would have been the lightest solution on the market.

When the launchPad came out, we knew that it would be a platform that people could easily afford, and would make a great solution for the servo deploy issue.
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ServoChron Lite

Post by U.S. Water Rockets2 » Fri Aug 05, 2011 12:41 pm

Skymeat wrote:Great project! by the look of it you could pack the guts into a super tiny package if you pull the IC.
You obviously know your stuff! We were saving this for a later date, but since you brought it up, we are proud to give you a preview of the newest member of the ServoChron™ family: ServoChron™ Lite!
lite.jpg
The concept behind this design is that you use the launchpad as a configuration tool and set up your parameters and then pop the chip and install it into the socket on your rocket. The whole design is made from a socket and a couple of LEDs and resistors that cost pennies apiece.

The whole controller can be assembled for under $2.00 and weighs less than 1 gram. This means that the ServoChron™ Lite is 1/20th the cost, 1/6th the weight, and 1/4 the size of commercially available products with similar functionality.

By the way, the MSP430 LaunchPad comes with not one, but TWO microcontrollers, so if you purchase a $4.30 launchpad, you have enough microcontrollers to make TWO of these ServoChron™ Lite systems!

Of course, the building of this system is a bit more involved, but can be simplified down to a air wired circuit that fits inside the footprint of the socket. About a dozen solder joints is all you need to build this setup.

We're finalizing some instructions on how best to power the MSP430 and will have schematics available shortly.

If you want to take the idea and adapt it for your own designs, feel free to do so. We want to encourage you to take the idea and expand upon it and spread the work around to help as many people as possible!
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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by Skymeat » Fri Aug 05, 2011 9:20 pm

Thanks for the awesome reply. Sorry to out your idea early LS: from here on out.

I read a bit about the TI stuff, pretty cool dev stuff. I think I'm going to play a bit with them and see what I can come up with.


Thanks,
Skymeat



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by U.S. Water Rockets » Sun Aug 07, 2011 12:47 am

Skymeat wrote:Thanks for the awesome reply. Sorry to out your idea early LS: from here on out.

I read a bit about the TI stuff, pretty cool dev stuff. I think I'm going to play a bit with them and see what I can come up with.


Thanks,
Skymeat
Don't worry about the idea... it's all good. We enjoy discussing these ideas with fellow enthusiasts and it stimulates a not of new ideas for everyone.

There's an awful lot of really cool stuff coming out of TI. Their low power stuff cannot be beat. Check out their energy harvesting appnotes and think of how cool it would be to put a logger on a rocket with a tiny solar cell and a transmitter. It could run virtually forever sending a signal you can triangulate the location from. The tracking transmitter we have now only has batteries and will die after a few days. You only have so long to find the rocket that way. This could run pretty much forever.



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by janssene » Thu Aug 11, 2011 10:18 am

Any ideas/suggestions on how to mount this board on the rocket (there are no mounting holes in the board which is normally used) ?



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by U.S. Water Rockets2 » Thu Aug 11, 2011 1:25 pm

janssene wrote:Any ideas/suggestions on how to mount this board on the rocket (there are no mounting holes in the board which is normally used) ?
You have a bunch of options. You could just get a roll of that double-sided sticky foam tape and stick it down. This is one of the very few ways that you can attach anything to corriflute board.

You can also make some mounting holes in the board by drilling holes in the MSP430 LaunchPad in the areas where there are no parts or traces. The areas where the rocket ship logo and the TI logo are printed on the board are otherwise unused and can be drilled out for mounting the board. See the drawing below:
ServoChron2_Drills.jpg
There are other places you can drill as well, but 2 holes should be plenty to hold the board in place.

Good luck!
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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by janssene » Thu Aug 11, 2011 2:28 pm

Ok, thanks for the reply. I will give it a try.

ps. Would it be possible to get a copy of the source code ?



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by U.S. Water Rockets » Thu Aug 11, 2011 8:42 pm

janssene wrote:Ok, thanks for the reply. I will give it a try.

ps. Would it be possible to get a copy of the source code ?
Another mounting method would be to get a square of that "hook and loop" fastener with the adhesive backing and then you have a strong mount that is removable and needs no modifications.

What do you need the source code for? Do you have an idea for a new feature you would like added to the next version?



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by janssene » Fri Aug 12, 2011 4:31 am

Not yet, I'm a software developer (Java, C++) in my daily job for enterprise systems. No experience in this kind of stuff. So I'm just curious on how it works.



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Re: ServoChron(tm) Firmware Update (Dual servo control)

Post by U.S. Water Rockets2 » Fri Aug 12, 2011 1:17 pm

janssene wrote:Not yet, I'm a software developer (Java, C++) in my daily job for enterprise systems. No experience in this kind of stuff. So I'm just curious on how it works.
At the moment, we're not distributing the firmware due to a couple of reasons:

1) This is a "do it yourself" project that we are trying to provide support and assistance to people who may be beginners. We want to help people learn about building hardware and about electronics. If other people start changing the firmware around then we will make it more difficult to troubleshoot problems that people encounter.

2) There's a guy who lurks all the water rocket forums looking for good ideas to swipe and publish on his personal website as if he thought of them. If we released the source code he could take out the copyright messages and then publish (or sell) the modified code as his own.

3) There's literally dozens of good websites that have sample code for the LaunchPad, which would easily be more useful to someone just learning. The source code for this project uses some extremely unusual constructs to be able to fit in the limited memory available and would be hard to learn from.

Thanks for the feedback!



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