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Servo Timer II

Discussion about deployment systems including altimeters, timers, air speed flaps, servo systems, and chemical reactions.
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air.command
Senior Member
Senior Member
Posts: 183
Joined: Wed Jul 09, 2008 5:20 am

Servo Timer II

Post by air.command » Thu Jun 30, 2011 1:53 am

Hi everyone,

We've been working on the next iteration of our servo timer over the last few months, and after much procrastination it's finaly finished.

Some features include:

* 6 - 9V operation. (see Power note below)

* Single RC servo output - Can drive most common RC servo motors up to ~1A for short periods.

* Configurable servo START and END positions - Allows you to customize how far and which direction your servo motor will move.

* 0-12 second delay selectable in 1 second increments - Simple rotary switch interface.

* Built in 2G acceleration switch for launch detect - No need for any external components. Just plug in a servo and battery and you are ready to go.

* External make or break wire trigger - You can directly connect other mechanical switches with normally closed or normally open contacts, custom trigger mechanisms, pressure switches etc. to trigger the timer.

* External 3V - 12V hi/low trigger - You can connect most existing rocket flight computers, altimeters, magnetic apogee detectors with pyro or digital outputs directly to the timer without additional interface hardware.

* External timer output - You can drive other external circuits when the timer activates.

* High-brightness 'ARMED' status LED visible in broad daylight from over 50 feet away. - You can see that the timer is armed from a safe distance before launch.

* Timers can be cascaded - You can easily connect any number of the timers together for more complex functionality. One timer can control a drogue parachute, while a second can deploy the main parachute. Or use one for a staging mechanism that triggers a second to deploy a parachute after staging.

* Timer self ARMs after 5 seconds after power on, Or can be configured for manual ARM.

* ICSP connector for firmware updates

* Weight: 6 grams

* Dimensions: 25mm x 43mm (1 x 1.7 inches) - The small footprint allows it to comfortably fit inside T8 FTC rockets.

Power: Although the timer will run from lower voltages, you need to be careful as a regular servo's torque and speed will be reduced and may cause problems with the reliably of the deployment mechanism. If you are after weight and space savings you can make a 2S pack from two of these 70mAh 20C LiPo batteries:

http://www.hobbyking.com/hobbyking/stor ... oduct=7566

Each of these batteries weighs a mere 2 grams and can deliver a whopping 1.4A. We use these with our timers. When weight isn't an issue then just clip in a regular 9V battery, or a battery pack made from single 1.5V cells.

We've done close to 20 flights with these timers now ranging from small slow rockets to big fast ones. We've also been using them with the uMAD from Whooshtronics for apogee detection. It serves as a good back up deployment mechanism while you test out your own system.

With the release of this version, we are also making the .HEX file and PCB layout files available on request for the previous version ( V1.6 FC - ) If you prefer to build the timers yourself.

Cheers

- George


http://www.AirCommandRockets.com

Mike J96
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Posts: 6
Joined: Sun May 15, 2011 12:54 pm

Re: Servo Timer II

Post by Mike J96 » Fri Jul 08, 2011 1:11 am

Hi,

I have a question about your deploy timer. What extra features are included for the $40 when compared to the other one listed here http://www.wra2.org/forum/viewtopic.php?f=5&t=1580 which I can get for around $4? SC:

That is a really big differince in price TC:

Is the servo motor included in the price or will I have to buy that too? :?: :?:

Are batteries included? :?: :?:

Mike RAT: RAT: RAT: RAT: RAT: RAT: RAT: RAT: RAT: RAT:



air.command
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Posts: 183
Joined: Wed Jul 09, 2008 5:20 am

Re: Servo Timer II

Post by air.command » Fri Jul 08, 2011 5:05 am

Mike J96 wrote:Hi,

I have a question about your deploy timer. What extra features are included for the $40 when compared to the other one listed here http://www.wra2.org/forum/viewtopic.php?f=5&t=1580 which I can get for around $4? SC:

That is a really big differince in price TC:

Is the servo motor included in the price or will I have to buy that too? :?: :?:

Are batteries included? :?: :?:

Mike RAT: RAT: RAT: RAT: RAT: RAT: RAT: RAT: RAT: RAT:
Hi Mike,

Thanks for the good questions. You do indeed need a battery and a servo motor with the servo timer II (STII) as well. The launchpad timer is certainly a cost effective option to go with if you like to tinker with micro controllers. Texas Instruments actually make a loss on these development boards, but for them it's worth the few lost dollars if they can get a new developer to learn about their controller family. The cost of the launchpad timer is actually closer to $10 by the time you add a power switch, push button, battery connector and servo motor connector.

There are a number of factors that affect the price of the STII. The most expensive component on the board is the built-in acceleration switch which costs close to $8. While you can of course make a simple acceleration switch yourself, you will need a place to mount it and make sure it's robust enough. You then need to calibrate the switch for your needs. We've used lots of different home made G-switches over the years, but these commercial units are the lightest, smallest and most robust we have come across. We have switched to using these now almost exclusively. That's why they are commonly used on pyro rocket electronics. You could of course use it with the launchpad too, but now you are now looking at closer to $18. (Assuming it didn't cost you anything to ship it from the distributor.)

The servo timer II comes fully assembled & tested and is ready to use out of the box. There is no need to download and install any software, and no soldering is required. Just plug in a servo and battery and you are good to go. For people who don't own a soldering iron or are not comfortable with having to do their own assembly, and doing firmware updates then the STII is a good alternative.

The two servo controllers also have a different feature set (see my first post), so depending on what your requirements are, one may be a better option for you than the other. While it is possible to add extra components to the launchpad to match some of the features of the STII, you may have to order them, and not only pay for the components but also their shipping costs. For example purchasing anything outside the US from digikey incurs a flat $30 delivery fee. You will also need to update the firmware to support the new functionality. But that can be a part of the fun if you enjoy doing that.

If you are really pressed for space for example in a narrow body rocket then the STII has a footprint of around 1/3 the size of the launchpad, and weighs less than half the weight.

The feature set we've put into the STII is what we have found useful over the years of flying similar timers and using them for different applications on hundreds of flights. Some of the features have also been requested by other rocketeers.

The $39 covers all parts, PCB, assembly and testing labour costs, packaging, FREE international shipping and paypal transaction fees.

Ultimately it comes down to what features you are after, and what level of development you are interested in doing. If you really like to do everything yourself, like to program micro-controllers and have the tools already then you can build a simple controller yourself for a couple of dollars like this:

http://www.youtube.com/user/ScienceSpic ... qn8kuQSUhA

That's why we always make the circuit diagrams, PCB layouts and code available for free for those that want to make the timers themselves.

Or if you want to do less development yourself and just buy the main components and assemble them, and price is the most critical criteria then the launchpad timer is a good option for you.

Or if you want to buy a fully assembled and tested flexible unit specifically designed for water rockets then the STII is a good option.

Or if you have a big budget then you can buy a lot more capable hardware that can do more that drive servos, but you also pay in proportion.

I hope that helps to answer some of your questions.

Cheers

- George


http://www.AirCommandRockets.com

Mike J96
New Member
Posts: 6
Joined: Sun May 15, 2011 12:54 pm

Re: Servo Timer II

Post by Mike J96 » Sat Jul 09, 2011 2:08 am

Thank you for the explanation TH:

I'm going to stick with the timer built with the launchpad because I am a student and $40 is a little steep for me. Besides that, I already have a launchpad which I used for removing the date stamp from my camera so the cost of this one is even less. I just need a servo motor and a battery and I am good to go PH:

The size of the board is not an issue since I use a 2 liter bottle for my rocket.

Thanks again for taking the time to reply to me TH:

Mike RAT: RAT: RAT: RAT: RAT: RAT:



air.command
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Joined: Wed Jul 09, 2008 5:20 am

Re: Servo Timer II

Post by air.command » Sat Jul 09, 2011 6:02 am

No worries Mike, if you already have the launchpad then that's what I'd go with as well.

Cheers

- George


http://www.AirCommandRockets.com

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jerm
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Joined: Sun Sep 27, 2009 1:14 am

Re: Servo Timer II

Post by jerm » Sat Jul 09, 2011 7:32 pm

Hi,

I have the Servo Timer II and they are fantastic. Right out of the box it works. I don’t have a lot of electronic experience and it is nice to have a product that you just plug and play. The servo motor just plugs right into the Servo Timer II, plug the battery in and set the servo and you are up and running.

Servo Timer II in small and will fit into FTC, my next project. The Lanchpad is a much larger board and will work with PET bottles. Both are good products and I prefer the Servo Timer II.

Thanks George for the effort in developing the product.

Jeremy
DY Water Rockets.


DY Water Rockets

air.command
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Posts: 183
Joined: Wed Jul 09, 2008 5:20 am

Re: Servo Timer II

Post by air.command » Sun Jul 10, 2011 9:33 am

jerm wrote:Hi,

I have the Servo Timer II and they are fantastic. Right out of the box it works. I don’t have a lot of electronic experience and it is nice to have a product that you just plug and play. The servo motor just plugs right into the Servo Timer II, plug the battery in and set the servo and you are up and running.

Servo Timer II in small and will fit into FTC, my next project. The Lanchpad is a much larger board and will work with PET bottles. Both are good products and I prefer the Servo Timer II.

Thanks George for the effort in developing the product.

Jeremy
DY Water Rockets.
Thanks for the nice words Jeremy. :D I've started adding some hints and tips on the timer and also servo mounting suggestions here:


An FTC rocket is a fun build since it has a different set of challenges to regular bottles. I'd be interested to see where you end up getting your FTC from, as the ones we bought a couple of years ago were overly expensive. Good luck with the build, I look forward to the flight reports.

- George


http://www.AirCommandRockets.com

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jerm
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Posts: 39
Joined: Sun Sep 27, 2009 1:14 am

Re: Servo Timer II

Post by jerm » Wed Jul 13, 2011 4:56 am

Hi George,

I already have the FTC (12 Tubes and the end caps). Though the type of work I do I know a supplier/importer of the product.

It can be hard to get and unfortunately I am unable to give the details of the supplier on this forum. We can talk about this later privately.

DY Water Rockets


DY Water Rockets

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dutchwaterrocket
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Re: Servo Timer II

Post by dutchwaterrocket » Thu Jul 21, 2011 5:09 pm

rocket stII.png
recovery.png
Hi George,

This week i've tested out the servotimer, and it works GREAT!
It's real easy to set and use!
You guys did a great job designing and building the servotimer!
I've launched it three times and it recovered three times!
I love the g-switch!
Great job!

René
You do not have the required permissions to view the files attached to this post.



air.command
Senior Member
Senior Member
Posts: 183
Joined: Wed Jul 09, 2008 5:20 am

Re: Servo Timer II

Post by air.command » Sat Jul 23, 2011 3:07 am

dutchwaterrocket wrote: Hi George,

This week i've tested out the servotimer, and it works GREAT!
It's real easy to set and use!
You guys did a great job designing and building the servotimer!
I've launched it three times and it recovered three times!
I love the g-switch!
Great job!

René
Hi René, thanks for the feedback. I'm glad to hear the STII is working well for you.

Cheers

- George


http://www.AirCommandRockets.com

JamiePadilla
New Member
Posts: 2
Joined: Wed Sep 18, 2013 3:23 am

Re: Servo Timer II

Post by JamiePadilla » Thu Sep 19, 2013 1:11 pm

air.command wrote:Hi everyone,

We've been working on the next iteration of our servo timer over the last few months, and after much procrastination it's finaly finished. The full details of the Servo Timer II are now available here:


Some features include:

* 6 - 9V operation. (see Power note below)

* Single RC servo output - Can drive most common RC servo motors up to ~1A for short periods.

* Configurable servo START and END positions - Allows you to customize how far and which direction your servo motor will move.

* 0-12 second delay selectable in 1 second increments - Simple rotary switch interface.

* Built in 2G acceleration switch for launch detect - No need for any external components. Just plug in a servo and battery and you are ready to go.

* External make or break wire trigger - You can directly connect other mechanical switches with normally closed or normally open contacts, custom trigger mechanisms, pressure switches etc. to trigger the timer.

* External 3V - 12V hi/low trigger - You can connect most existing rocket flight computers, altimeters, magnetic apogee detectors with pyro or digital outputs directly to the timer without additional interface hardware.

* External timer output - You can drive other external circuits when the timer activates.

* High-brightness 'ARMED' status LED visible in broad daylight from over 50 feet away. - You can see that the timer is armed from a safe distance before launch.

* Timers can be cascaded - You can easily connect any number of the timers together for more complex functionality. One timer can control a drogue parachute, while a second can deploy the main parachute. Or use one for a staging mechanism that triggers a second to deploy a parachute after staging.

* Timer self ARMs after 5 seconds after power on, Or can be configured for manual ARM.

* ICSP connector for firmware updates

* Weight: 6 grams

* Dimensions: 25mm x 43mm (1 x 1.7 inches) - The small footprint allows it to comfortably fit inside T8 FTC rockets.

Power: Although the timer will run from lower voltages, you need to be careful as a regular servo's torque and speed will be reduced and may cause problems with the reliably of the deployment mechanism. If you are after weight and space savings you can make a 2S pack from two of these 70mAh 20C LiPo batteries:

http://www.hobbyking.com/hobbyking/stor ... oduct=7566

Each of these batteries weighs a mere 2 grams and can deliver a whopping 1.4A. We use these with our timers. When weight isn't an issue then just clip in a regular 9V battery, or a battery pack made from single 1.5V cells.

We've done close to 20 flights with these timers now ranging from small slow rockets to big fast ones. We've also been using them with the uMAD from Whooshtronics for apogee detection. It serves as a good back up deployment mechanism while you test out your own system.

With the release of this version, we are also making the .HEX file and PCB layout files available on request for the previous version ( V1.6 FC - ) If you prefer to build the timers yourself.

Cheers

- George
Hello friend I am using similar servo timer and now looking to get latest one,. Is there any updation? Please provide me some good information..



air.command
Senior Member
Senior Member
Posts: 183
Joined: Wed Jul 09, 2008 5:20 am

Re: Servo Timer II

Post by air.command » Fri Sep 20, 2013 3:11 am

JamiePadilla wrote:Hello friend I am using similar servo timer and now looking to get latest one,. Is there any updation? Please provide me some good information..
Hi JamiePadilla, I'll post an update as soon as new information is available. If you want to make your own I'm happy to send you all the files you need including the PCB file, HEX file as well as the source code. As an alternative you can always try USWR's timer.

- George


http://www.AirCommandRockets.com

JamiePadilla
New Member
Posts: 2
Joined: Wed Sep 18, 2013 3:23 am

Re: Servo Timer II

Post by JamiePadilla » Fri Sep 20, 2013 11:18 am

JamiePadilla wrote:
air.command wrote:Hi everyone,

We've been working on the next iteration of our servo timer over the last few months, and after much procrastination it's finaly finished. The full details of the Servo Timer II are now available here:



Some features include:

* 6 - 9V operation. (see Power note below)

* Single RC servo output - Can drive most common RC servo motors up to ~1A for short periods.

* Configurable servo START and END positions - Allows you to customize how far and which direction your servo motor will move.

* 0-12 second delay selectable in 1 second increments - Simple rotary switch interface.

* Built in 2G acceleration switch for launch detect - No need for any external components. Just plug in a servo and battery and you are ready to go.

* External make or break wire trigger - You can directly connect other mechanical switches with normally closed or normally open contacts, custom trigger mechanisms, pressure switches etc. to trigger the timer.

* External 3V - 12V hi/low trigger - You can connect most existing rocket flight computers, altimeters, magnetic apogee detectors with pyro or digital outputs directly to the timer without additional interface hardware.

* External timer output - You can drive other external circuits when the timer activates.

* High-brightness 'ARMED' status
led lights visible in broad daylight from over 50 feet away. - You can see that the timer is armed from a safe distance before launch.

* Timers can be cascaded - You can easily connect any number of the timers together for more complex functionality. One timer can control a drogue parachute, while a second can deploy the main parachute. Or use one for a staging mechanism that triggers a second to deploy a parachute after staging.

* Timer self ARMs after 5 seconds after power on, Or can be configured for manual ARM.

* ICSP connector for firmware updates

* Weight: 6 grams

* Dimensions: 25mm x 43mm (1 x 1.7 inches) - The small footprint allows it to comfortably fit inside T8 FTC rockets.

Power: Although the timer will run from lower voltages, you need to be careful as a regular servo's torque and speed will be reduced and may cause problems with the reliably of the deployment mechanism. If you are after weight and space savings you can make a 2S pack from two of these 70mAh 20C LiPo batteries:

http://www.hobbyking.com/hobbyking/stor ... oduct=7566

Each of these batteries weighs a mere 2 grams and can deliver a whopping 1.4A. We use these with our timers. When weight isn't an issue then just clip in a regular 9V battery, or a battery pack made from single 1.5V cells.

We've done close to 20 flights with these timers now ranging from small slow rockets to big fast ones. We've also been using them with the uMAD from Whooshtronics for apogee detection. It serves as a good back up deployment mechanism while you test out your own system.

With the release of this version, we are also making the .HEX file and PCB layout files available on request for the previous version ( V1.6 FC - ) If you prefer to build the timers yourself.

Cheers

- George
Hello friend I am using similar servo timer and now looking to get latest one,. Is there any updation? Please provide me some good information..



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