Welcome to the Water Rocket Forum, sponsored by The Water Rocket Achievement World Record Association.

Since our founding in 2003, we've become the largest, most sophisticated and ground breaking group supporting you, the serious water rocket flyer! Whether you are a beginner or an expert, the WRA2 has something for everyone.

A water rocket is a type of model rocket using water as its reaction mass. The pressure vessel (the engine of the rocket) is constructed from thin plastic or other non metallic materials (usually a used plastic soft drink bottle) weighing 1,500 grams or less. The water is forced out by compressed air. It is an example of Newton's third law of motion.


Hello Everyone. It is that time of year again. Time to approve changes to the competition rules for the new year.

You Can vote at:
viewtopic.php?f=32&p=19486#p19486

Please take the time to vote. TH:

ServoChron without MSP430 Launchpad

Discussion about deployment systems including altimeters, timers, air speed flaps, servo systems, and chemical reactions.
User avatar
U.S. Water Rockets
WRA2 Member
WRA2 Member
Posts: 398
Joined: Tue Jan 30, 2007 8:16 pm

Re: ServoChron without MSP430 Launchpad

Post by U.S. Water Rockets » Thu Mar 28, 2013 4:42 pm

DogLover wrote:Thanks for that USWR! That will be helpful.

-DogLover

Keep in mind that the design only has one LED and so you cannot rely on the LED for status the same as you can with the pair. It operates a little differently because of the way it is connected, so the main reason for including it at all was so you could see the timer was alive and ready.



Tony
WRA2 Member
WRA2 Member
Posts: 61
Joined: Sat Feb 16, 2013 3:39 am

Re: ServoChron without MSP430 Launchpad

Post by Tony » Fri Mar 29, 2013 1:29 am

bugwubber wrote:My current setup has power going from the battery separately to the board, the servos, an altimeter, and lights so that the servos get all the power they want even though my HXT900s work just fine powered from the board.
For low voltage, have you looked at these?
I'd like to take advantage of available pins on the board to power my altimeter, but I don't know if it is possible... or how to do it. I had never heard of the MSP430 before USWR's website... bought 2 of them right away (work great, too)... I can run all the wires but can't manipulate the code, it's a far cry from BASIC and HTML, so I'm probably SOL. A guy can still dream, right?


"Houston, we've had a problem..."

User avatar
bugwubber
WRA2 Member
WRA2 Member
Posts: 1086
Joined: Wed Dec 19, 2012 2:47 am

Re: ServoChron without MSP430 Launchpad

Post by bugwubber » Fri Mar 29, 2013 10:09 am

U.S. Water Rockets wrote: As promised, here's a draft of the ServoChron(tm) Lite Schematic. This design does work well on the bench. We have not tested this in a real launch, so just be aware it is still in testing. This design is an evolution of one we did test, and that one worked, but this one has a ton of parts removed to make it easier to build and smaller.

http://www.uswaterrockets.com/shared/Se ... inary).pdf

Our primary landing area is now totally off limits as the ice is very thin, so we are not able to launch. Our backup areas are still covered in snow. It could be a couple of weeks before we can launch again.

Let us know how you make out!
So I expected everything except R2 and its connections. Can't figure out why you have it there.


Bugwubber

Team S.P.E.W.

User avatar
Blenderite
WRA2 Member
WRA2 Member
Posts: 438
Joined: Mon Apr 09, 2012 3:49 pm

Re: ServoChron without MSP430 Launchpad

Post by Blenderite » Fri Mar 29, 2013 2:07 pm

Tony wrote:
bugwubber wrote:My current setup has power going from the battery separately to the board, the servos, an altimeter, and lights so that the servos get all the power they want even though my HXT900s work just fine powered from the board.
For low voltage, have you looked at these?
I'd like to take advantage of available pins on the board to power my altimeter, but I don't know if it is possible... or how to do it. I had never heard of the MSP430 before USWR's website... bought 2 of them right away (work great, too)... I can run all the wires but can't manipulate the code, it's a far cry from BASIC and HTML, so I'm probably SOL. A guy can still dream, right?
Did you some how get your hands on the code itself? I have been trying to get that and I haven't been able to.

-DogLover


-Blenderite

Check out my YouTube channel: https://www.youtube.com/c/Blenderite

"Get it right, then go for GREATNESS!"

User avatar
bugwubber
WRA2 Member
WRA2 Member
Posts: 1086
Joined: Wed Dec 19, 2012 2:47 am

Re: ServoChron without MSP430 Launchpad

Post by bugwubber » Fri Mar 29, 2013 5:08 pm

Tony wrote:
bugwubber wrote:My current setup has power going from the battery separately to the board, the servos, an altimeter, and lights so that the servos get all the power they want even though my HXT900s work just fine powered from the board.
For low voltage, have you looked at these?
I'd like to take advantage of available pins on the board to power my altimeter, but I don't know if it is possible... or how to do it. I had never heard of the MSP430 before USWR's website... bought 2 of them right away (work great, too)... I can run all the wires but can't manipulate the code, it's a far cry from BASIC and HTML, so I'm probably SOL. A guy can still dream, right?
That would be nice- a version of servochron that looks altimeter data and triggers after peak altitude. That sort of thing already exists out on the market though. The purpose of servochron was to be the $12 solution. Wish my coding skills weren't limited to HTML3.


Bugwubber

Team S.P.E.W.

uberpixel
Advanced Member
Advanced Member
Posts: 24
Joined: Sat Jun 07, 2014 12:11 pm

Re: ServoChron without MSP430 Launchpad

Post by uberpixel » Sat Jul 05, 2014 7:28 pm

bugwubber wrote:So I expected everything except R2 and its connections. Can't figure out why you have it there.
I realize that this is an old thread, but I'm trying to figure out why the ServoChron Lite schematic includes R1 (200 ohm) and R2 (1.0 Kohm)? Also, shouldn't R3 be 47 Kohm not 4.7 Kohm?

All of the information I can find on using the MSP430 standalone (as well as the TI schematic for the Launchpad) do not include these additional R1/R2 resistors and show 47K instead of 4.7K. There are some capacitors on RST pin shown on the TI schematic, but from what I've read, they are not generally needed with battery power.

Thanks in advance if anyone can help!

-uberpixel



User avatar
U.S. Water Rockets1
WRA2 Member
WRA2 Member
Posts: 1771
Joined: Sat Feb 03, 2007 3:24 pm

Re: ServoChron without MSP430 Launchpad

Post by U.S. Water Rockets1 » Sat Jul 05, 2014 10:30 pm

uberpixel wrote:
bugwubber wrote:So I expected everything except R2 and its connections. Can't figure out why you have it there.
I realize that this is an old thread, but I'm trying to figure out why the ServoChron Lite schematic includes R1 (200 ohm) and R2 (1.0 Kohm)? Also, shouldn't R3 be 47 Kohm not 4.7 Kohm?

All of the information I can find on using the MSP430 standalone (as well as the TI schematic for the Launchpad) do not include these additional R1/R2 resistors and show 47K instead of 4.7K. There are some capacitors on RST pin shown on the TI schematic, but from what I've read, they are not generally needed with battery power.

Thanks in advance if anyone can help!

-uberpixel
The Lite version was not intended to be a copy of the LaunchPad board, but the most minimal version that could be made and still be compatible and functional. Some of the parts were changed because the values are NOT critical and represent what we had on hand. If you build it as it is designmed, it will work. Don't sweat the minor changes.


Team U.S. Water Rockets
Visit USWaterRockets.com
Visit our Blog
Tune in to our YouTube Channel
Visit our Facebook page
Visit our Twitter Page
Opportunity is missed by most people because it is dressed in overalls and looks like work. --Thomas Edison

motorcyclepilot
WRA2 Member
WRA2 Member
Posts: 42
Joined: Sun Jul 19, 2015 5:19 pm

Re: ServoChron without MSP430 Launchpad

Post by motorcyclepilot » Mon Sep 21, 2015 3:22 pm

U.S. Water Rockets wrote:
bugwubber wrote:
DogLover wrote:What I am thinking of is hooking just the battery, servo, and launch detect switch up to a DIP socket and then put the chip in that. Then if I want to reprogram the chip, I just put it into a Launchpad and reset the time or servo position. That way it is a really small package. One thing, can I get a link to the 3.7v servos? I can't seem to find them. I ordered some Hobby King HK15178's a while ago and they don't work with the board. I suppose because they require too high of voltage. any help is appreciated.

-DogLover
My current setup has power going from the battery separately to the board, the servos, an altimeter, and lights so that the servos get all the power they want even though my HXT900s work just fine powered from the board.
For low voltage, have you looked at these?
Nice find with those servos. We havw not seen those before. We will check them out next time we're padding out an order that is underweight. :wink:

As promised, here's a draft of the ServoChron(tm) Lite Schematic. This design does work well on the bench. We have not tested this in a real launch, so just be aware it is still in testing. This design is an evolution of one we did test, and that one worked, but this one has a ton of parts removed to make it easier to build and smaller.

http://www.uswaterrockets.com/shared/Se ... inary).pdf

Our primary landing area is now totally off limits as the ice is very thin, so we are not able to launch. Our backup areas are still covered in snow. It could be a couple of weeks before we can launch again.

Let us know how you make out!

I've been communicating with Uberpixel about this for a while when I found this thread today. The link to the PDF is dead. Are you still sharing it? I could REALLY use some direction in this area.

Thanks

Found it! http://www.uswaterrockets.com/shared/Se ... ematic.pdf



Post Reply