Paul's message (above) was, I believe, directed to you. When you reply please be sure to thank him for following along to see how our project is progressing, especially since he's in Spain. Then, read carefully and heed what he wrote. Don't get too far along with an idea that's not practical, or that's too complicated. As he said, using a solenoid may require more voltage than we have available and it may require additional and circuitry for the BOE. This is extra cost and work we don't necessarily need to do. "Simpler is better" in my estimation.
"What's the budget we have to work with?" you asked. "There is no budget", Mr. Kibler replies. The balance in our team account is $0.00 and so we need to be innovative. I'll buy what we need once I'm convinced that we really need it. I can also scrounge for materials from various and sundry places from time to time. "Necessity is the mother (or father) of invention" some say. In this case "Invention is the mother of necessity..."
========================================
Sylvie, mi amgio,
Como esta?! So you're in Espana? What a lucky guy. Are you in Andalucia? Madrid? The Pyrenees? I'll bet spring has come on full to the gold coast. How long have you been there? How's the calamari and sangri? You lucky guy. It's 27 degrees and the winds are 20 mph. It's cold out there!
Thanks for logging in Paul. Dylan and Andrew are getting to the point where they should be logging onto the forum seeking guidance. Andrew wrote and tested a subroutine for yesterday's practice that should activate the rover after it reads a certain number of consecutive 0's after landing. Figuring out where and how to intergarte it into the main program is their challenge and so I'm sure they would appreciate your and Tracy's help. I certainly do.
Send us a picture of 'Sylvie in Spain', why don't you? You can even gloat and say, "Wish you were here."
Solenoids also need some circuitry to be operated by the Stamp, and that might be a bit much. It´s worth looking into, but there are some difficulties that might make it impractical in your situation.
Jake and Emily,
As I just said in my previous post, I would read and heed Paul's sage advice..."
At our last practice, we tried to accomplish adding a subroutine whose purpose was to call the movement subroutine after ten consecutive zeroes were read from the MAWD. We began by writing the subroutine so that when any altitude above 200 is reported by the MAWD, a movement subroutine would immediately start. However, the program consistently starts regardless of the altitude goal we set. Could you please take a look at the attached program code and assist us?
The only portion of the program of which we are unsure of is the fact that it depends on retrieving the current altitude from a variable labeled "feet." Although the comment where the variable is declared indicates that this variable should hold an integer equivalent to the altitude in feet, we are unable to determine this positively as we are confused on the MAWD subroutine itself functions, shown below.
MAWD_get:
' alternative code to acquire MAWD data, uses DEC5 instead of STR in SERIN
PULSIN MAWDin,1,iobyte ' the purpose of this is to synchronize with the MAWD timing.
PAUSE 10 ' this assures the SERIN will start waiting in the silent period before
' a MAWD xmission
feet=0
SERIN MAWDin,84,64,MAWDnot,[DEC5 feet]
MAWDnot:
RETURN
Specifically, we are confused as to how the line "SERIN MAWDin,84,64,MAWDnot,[DEC5 feet]" functions. We have a primitive understanding of the SERIN command, but we were unable to determine how the rest of the functions work. We believe that better understanding this portion of the program will allow us to fix the problem in our new subroutine.
Another issue we are currently discussing is whether to use one or two BOE's. Because the I/O slots on the current BOE are all taken, except for one, and we plan on adding two servomotors in the near future, we figured that this would be our best option. In addition, we think that it will allow more data to be sampled as the STAMP is spending significantly less time moving the servo motors, and possibly calculating it's location, provided we meet our stretch goal of GPS-assisted navigation. What are your thoughts on both of these issues?
Paul- Thanks for the recommandation from Spain! I hope you're having a great time in a foreign country! We have decided against using a solenoid, for the reasons you posted, and because we don't actually need one in our design.
Mr. Kibler- I've got a really good feeling about our new design. I understand what you're worried about, but to every question there is an answer. The prototype will be completed in two weeks. Also, This is un-ARLISS related, but do you ahve any recommandations for classes next year for me? There are so many!
Emily- We need to have one final conversation about design and then we can get into building it. Take heed of what Mr. Kibler is worried about the design. As he said, it is always good to have a back-up plan.
Obie- Below is a link to an interesting creation I found on the parallax website. Pay attention to the design, not the whole parallax board speech.
You may want to ask Paul if he has any ideas or suggestions for a simple and fail-safe parachute release mechanism. He's an advanced rocketeer, a clever and likeable guy, and he's launched lots of rockets. Really BIG rockets. Sometimes we have to learn to ask for advice even when we think our idea is "better." I'll bet he-- and others who follow along on the forum-- have some ideas for a simple parachute release mechanism that's not complicated and that's easy and affordable to build. All you have to do is ask.
RE: Selecting classes for next year, the first thing I would ask is, "Where do you want to go when you finish high school?" If you're looking toward engineering, take four years of science and all the math you can. If it's International Affairs, take as many language courses as you can. If you think you may be invited for the Honors Writing Prompt, prepare. I can show you how (Google "freshman honors writing prompt examples" for starters. There's also a time management component.) I'd be glad to meet with you, and your parents if you want, to help guide you along. Like the Knight Templar said in the movie, Indiana Jones and the Search For the Holy Grail, "Choose wisely." Your future depends on the choices you make: for better or for worse.
. Some alternate ideas for a parachute deployment mechanism: Mechanically, Idea #1 is a simple device but it requires dual-deployment capability, which the MAWD has, and black powder. How we would get the parachute to detach ONLY after it has landed? Program the BOE to output an electric signal that ignites the black powder AFTER the ASP-BOT has landed, after it reads ten (twenty, etc.) 0's. Or send a signal from the BOE to heat up a wire that burns through the "string" holding the parachute. Other ideas...?
I see two options for detaching the parachute after touchdown:
1) Program a servo to rotate "something" that releases the parachute (an elastic, etc.)
2) Program the BOE to heat up a wire that burns through monofilament (fishing line) holding the parachute. Sylvie, what do you think? How would you rank these in order (1-5) from most practical to least practical?
How's Spain? I see that Barcelona beat Arsenal 3-1, a good win for the "home" team. Are you able to watch any football in Spain?
Thanks Mr. Kibler! Although idea #1 is simple, i'm worried about the black powder. I think it would also be safest to stay away from pyro release mechanims. What do you think Emily? Idea #3 is what really caught my attention. It plugs straight into a BoE board, and it appears to me as that the clip on the tip flip upwards and releases the parachute.
Sylvie- Again, like Mr. Kibler said, what are your ideas for a release mechanism that is simple yet effective and made from things we could salvage from home? Have a great time in Spain!
Idea #3 is attractive because it does have a plug-in similar to the servomotor's plug-in. Drawbacks:
1) Just because the device may connect to the BOE, is it compatible?
2) Where would we plug it in? Remember that we already have very limited input/output slots available and we need to free up two for the ASP-BOT (robot's) two motors.
3) The cost is 140 Euros. How much is that in dollars? Please convert this to USD ($$$) and post the price to the forum. Since the cost is in Euros the item is probably somewhere in Europe (England?) So there would be additional shipping cost (add 15-20 Euros.) It may take weeks to arrive from Europe. What if we buy it and we can't use it? This has happened in previous projects and the cost comes out of my pocket. Remember that basically we have no budget right now (*except what Mrs. K allows me to spend out of my allowance...!)
4) The "servo is activated by an altimeter - or similar device – by the Servo Control unit (not included), How do we make the MAWD (the altimeter) output a signal at '0' feet after it lands? Isn't the MAWD's input/output wire already being used to input altitude data to the BOE?
What about idea #2? It seems simple and I "think" we have all the parts we may need.
Andrew and Dylan, Please offer input since you are familar with how the ASP's circuitry works and Jake and Emily aren't. They need your input and guidance. We should be working as interdependent subsystem teams, not independently, with senior team members and the team captain overseeing and guiding the process.
I´m in Castilla y Leon, in Salamanca, studying Spanish again, but only for one week this time (It´s spring break). No calamari and sangria - tortilla espanola y bocadillas, and German beer at an Irish pub watching Barcelona defeat Arsenal. Here it´s in the mid-to-upper 50s, with sunshine, I¨m in shirtsleeves, and the Spaniards are in heavy winter coats with scarves and hats.
You should be able to test your ¨do I know when I´ve landed?¨ routine by putting the MAWD into that vacuum bottle, running the wires out to your Stamp, and doing the ¨suck the air out¨ test. Of course that won´t be the real test - you´ll still need to keep your fingers crossed while you´re flying the thing. But it might flag some obvious problem in time for repair.
I´m in Castilla y Leon, in Salamanca, studying Spanish again, but only for one week this time (It´s spring break). No calamari and sangria - tortilla espanola y bocadillas, and German beer at an Irish pub watching Barcelona defeat Arsenal. Here it´s in the mid-to-upper 50s, with sunshine, I¨m in shirtsleeves, and the Spaniards are in heavy winter coats with scarves and hats.
You should be able to test your ¨do I know when I´ve landed?¨ routine by putting the MAWD into that vacuum bottle, running the wires out to your Stamp, and doing the ¨suck the air out¨ test. Of course that won´t be the real test - you´ll still need to keep your fingers crossed while you´re flying the thing. But it might flag some obvious problem in time for repair.
Hola Sylvie!
Bocadillas and bocarones and cerveza. What a life! You must be in near-heaven at 50 degrees after those wild Wisconsin winters. Spring is coming on slowly here after near-record snowfall. It feels very typically March here in Dunbarton. No bocadillas or bocarones, though micro-brew is on tap for this evening.
Tyler, who was on the ARLISS team the past two year and who is now at Swarthmore (early decision with scholarship) stopped by on Sunday while was home on spring break. He said, "What do you hear from Sylvie and Dr. Allen?" Now I can tell him (via his sister, a student of mine), "Sylvie is alive and well in Esapana!"
I don't think the Rocketeers have quite figured out the sequence of the program code to test it in the vaccum chamber yet. That's where they're stuck and that's where they're seeking input. The ASP-BOT will move and collect data at the same time, but not predictably. They're working on getting the code in the right order so we can test it in the vaccum chamber a week from Saturday. I'm not convinced they have the code 100% yet though, even if it happened to be in the correct sequence. But they are learning and moving ahead, much moreso than even last year.
Looks like we may well be aiming for a mid-June ARLISS launch-- two months to build and program. I was offered a position on faculty at King's Academy in Amman in August and I just may well do it! It's just a hop, skip and jump from Spain, you know. You're always welcome to stop in: here in NH, there in Jordan, wherever I happen to be.
Jake,
I really like Mr Kibler's 2nd idea, its simple and elegant. Also it looks like there is less room for error then in our design, which could prove difficult to program.
Mr. Kibler, Thank you for the alternative ideas.
Sylvie, Thank you very much for checking in even when your in Spain, Have you scene what Jake and I are trying to make yet? Also do you have an ideas?
if not I'll attach it just in case.
We (Jake and I) are going to replace the pneumatic actuator with a metal bar a servo motor, the servo motor will turn and push the bar and in turn the bar with push the two lever apart and the spring will send the disk that is attached to the parachute off. Again your thoughts would be greatly appreciated
Emily
Emliy- I'm glad to know you're still out there. Contact is key. by that I mean that we need to atleast get in touch four-five times a week. I agree, the price for idea three is around 175 dollars plus shipping. Even if we had a budget that would be out of it. I think we've limited it down to two ideas. Eitehr ours, or Idea two. Although I don't see any errors with our design, I do have to agree with Mr. Kibler on a couple of things about it. It appears to me we have settled on an idea. I'll create a blue print of it and create the prototype.
Thanks all
-Jake-
Problems that can be solved with Idea #2. First off I would like to say the this is VERY simple and efficent. we could definitly build this.
first problem: Those rubber bands are very tightly stretched. What if they broke? We have to use something stronger.
Secondly: How would this attach to the parachute? in the picture it is attached to a solid object. How can you launch and object that is not being pulled downward originally?
I'm sure we can work these out.
Emily- The idea uses a servo. Can you work on the program for it? The prototype will be done for two weeks from now.
...I'll create a blue print of it and create the prototype.
-Jake-
Please work with your subsystem team partner on making the prototype. Use other team members-- Dylan, Andrew, Paul (Sylvie), etc.-- as a sounding board; ask for their advice before you get up to your ears in alligators (see photo below.) Alligators are not very friendly sometimes
(Alligators are, of course an analogy. Emily, what is an analogy? And Jake, what are the alligators an analogy for?) NOTE: No alligators were harmed in making this e-mail.
Thank for the advice Mr. Kibler. I'll make sure to work on this with emily. You're right, alligators are not friendly. Get better and come back to school!
Emily- We should meet this weekend to work on the prototype!
Sounds good Jake, but as Mr. Kibler said I should be helping you with the blue prints and the prototype. How does Sunday sound? Also Dylan has mentioned that he would like to be there to help us if needed when and if we get overwhelmed.
...I should be helping you with the blue prints and the prototype... Dylan mentioned that he would to help us.
Emily
Emily,
Good for you for citing the source for your definition of 'analogy.' It's always proper to quote the source when you're using someone else's words or work.
I like the idea of Dylan joining you this weekend to help guide things along. He has a good overview of the project and he may think of seemingly small things that you and Jake may otherwise miss (for example, where will the parachute attach to the ASP-BOT so that it comes out of the tube free and clear? It can't really attach to a wheel, can it?) A three-person team always seems to work better than two.
The analogy is the same as "Don't swim in dangerous waters". By this I mean, if you venture to far away from the original group, then tou probably will get eaten. Yum. Emily- Since the design needs a couple modifications to make it work for releasing a parachute instead of popping of a cap, lets have both of us draw up the design and where it will be located. The most effective of the two is what we should go with.
The analogy is the same as "Don't swim in dangerous waters". By this I mean, if you venture to far away from the original group...
This seems like an analogy for an analogy. How does, "Don't get up your ears in alligators" relate to designing and building a parachute release mechanism...?
Sounds good Jake, I'll Email mine to you as soon as its done. Sunday? Sundays are best for me because then I can get rides. Also I'm going to need your address so that I can map quest please email that to me.
Thanks
Emily
Emily- Sunday works great! it'll have to be after three though. I have training all day. I didn't get your email sorry. Goldsberry@gsinet.net is the address, so well set up the exact time over that. what do we need for materials? i'll try to salvage something.
Mr. Kibler- Sorry about the analogy for an analogy, it's like a question for a question. I honostly don't know what the analogy means. Its on the tip of my tongue but I cant spit it out. That's why I answered with analogy, figuring maybe then the answer would come to me.
-Jake-
... I honestly don't know what the analogy means. Its on the tip of my tongue but I cant spit it out.
Jake and Emily,
Here's what I meant by the analogy: Don't get too wedded to an idea that may not work in the long run. I'm not saying that you idea will, or won't work. I'm just saying, "Watch out for the alligators that wait in deep water." Once you're in too deep, you may not be able to get out. You may run out of time with a more complex idea. Don't dive in too deep until you're certain it will work and until you're sure there's not a simpler and more effective way to do it.
Case in point: Attached is a picture of a possible tire for the ASP-BOT. The good news is two-fold: 1) It fits perfectly inside the payload tube, and 2) It was free. I scrounged two of them from the junkyard (*the source of many free and excellent engineering materials.)
The downside is that it's heavy, maybe too heavy for the servos. It might drain too much voltage because of its weight. But they ARE made of solid rubber. I knocked the white plastic center out and what is left is the tread. We'll have to engineer a hub for the servos.
It would be easy for me to wed myself to the idea that "This is THE tire for the ASP-BOT", simply because it fits and because it was free. While those are considerations they shouldn't be the deciding factors in choosing the right tires. Does that make sense?
Obie (and others): What are your thoughts about using this tire? One of the first things we have to do Obie, is mount the servos and the tires on some sort of a platform. Then we'll lay out the circuitry loosely on the platform to see where things fit best. I'd like to hear your thoughts on the tire and on laying the circuitry out. Also, we need some sort of sturdy material for the platform, guys and gals. The platform is the wooden piece that everything is mounted on right now. I would rather not use wood. What about G10 fiberglass? Carbon fiber? What do you have at home that we might be able to use? Bring it to the next practice please
Finally, two people have contacted me about joining the team. If they're interested, the same guidelines apply to them that applied to you: three try-outs, a decision, and three missed practices allowed. Dylan, you may know one of them. His last name is St. Clair (or something like that) and I think he's from Henniker. He supposed to be a bright and capable kid. Andrew, the other is Justin Da Costa. Contact me by PM and let me know your thoughts.
Idea #3 is attractive because it does have a plug-in similar to the servomotor's plug-in. Drawbacks:
1) Just because the device may connect to the BOE, is it compatible?
Based on the specifications, it should be compatible with the Parallax servo motor. Remember, they are only selling an attachment which is in theory compatible with the type of servo motor Parallax sells.
2) Where would we plug it in? Remember that we already have very limited input/output slots available and we need to free up two for the ASP-BOT (robot's) two motors.
Since this is an attachment, the only input/output slots required would be those required by the motor. That's still a lot of slots, if we are going to be using only one BOE.
3) The cost is 140 Euros. How much is that in dollars? Please convert this to USD ($$$) and post the price to the forum. Since the cost is in Euros the item is probably somewhere in Europe (England?) So there would be additional shipping cost (add 15-20 Euros.) It may take weeks to arrive from Europe. What if we buy it and we can't use it? This has happened in previous projects and the cost comes out of my pocket. Remember that basically we have no budget right now (*except what Mrs. K allows me to spend out of my allowance...!)
The mechanism costs $193 US dollars, plus shipping. I think a safe estimate of the mechanism plus the cost of shipping would be about $220 US dollars. When I look at the cost of this device and compare it to it's effective functionality, I'm quite discouraged. I don't think we should completely remove this as a possibility, but it's a very pricey one. We should definitely investigate the alternatives first.
4) The "servo is activated by an altimeter - or similar device – by the Servo Control unit (not included), How do we make the MAWD (the altimeter) output a signal at '0' feet after it lands? Isn't the MAWD's input/output wire already being used to input altitude data to the BOE?
It is my understanding that the servo would be connected to the BOE, which already receives data from the MAWD. A new line would have to be added to the beginning of our movement subroutine to activate the servo that is connected to the mechanism.
I hope that Andrew won't mind me sharing the good news with you. He was notified today that he was accepted for admission at Hawai'i Preparatory Academy in August and hearty CONGRATULATIONS are certainly in order! Andrew has worked VERY hard for this and he deserves a hearty pat on the back (or two!) It looks like we'd better get the ASP-BOT ready for a JUNE launch in Nevada... Congratulations Andrew!
Well done,
Mr. Kibler
Hello Andrew,
...It is my pleasure to inform you that you've been accepted to HPA for grade 11. Congratulations! The acceptance package was mailed out today. You should receive it by early next week. Should you have any questions about HPA in making your final decisions, please feel free to give us a call.
Again, congratulations. We hope to see you in August.
Aloha,
The Admission Office
Hawai'i Preparatory Academy
It is my understanding that the servo would be connected to the BOE, which already receives data from the MAWD. A new line would have to be added to the beginning of our movement subroutine to activate the servo that is connected to the mechanism.
-- Andrew
Yes, that's right Andrew. I was hoping that you or Dylan would pick up on this. The signal to the servo (if we use one) would be an output from the BOE.
Are you meeting with Jake and Emily this weekend? Jake has some new insights to share with you now that he's seen the tire I'm proposing to use (see picture above.)
Hi all-
Today I got a chance to really study the new tires. The only problem is how are we going to put a release mechanism on this? Mr. Kibler and I have tried to think of numerous solutions, but they all seem to end with one problem or another. Any ideas? How about you Sylvie?
-Jake-
Hi all-
Today I got a chance to really study the new tires. The only problem is how are we going to put a release mechanism on this? ... Any ideas?
-Jake-
Jakester,
You have to give more specific information to people. For example, "...how are we going to put a release mechanism on this?" What does "this" refer to? Most people will have no idea. Add details. Be specific. Be clear.
Hi all, sorry about the confusion. First off (if forgot to post this in my last post) CONGRATULATIONS ANDREW!!!! I hope you have an amazing time there!
secondly, by "this" I meant the wheel or the ASP-bot. "How are we going to put a release mechanism on the wheel or the ASP-bot withought ripping the wheel off our breaking anything? WE ahve no margin for error.
Have a good weekend!
-Jake-
I would like an update on where the movement subroutine stands and how close you are to integrating it into the main program. I haven't seen any information about it on the forum for a while.
You have two goals for the next practice:1) Download your program, send the robot across the ground (indefinite distance), and collect temperature, humidity and CO2 data all at once.
This was a goal for last practice but I never did see the robot move with the program installed. That's why I gave you a BOE and servos,Dylan, and a BOE-BOT, Andrew: so you can figure the program out and get it working.
2) Dowload your program to last year's ASP, put it into the vacuum chamber, then see if your program will activate a servo AFTER the vacuum chamber returns to 1 ATM (= 1 atmosphere, or air pressure at ground level.)
Your goal for having your final program fully operational is four weeks from our next practice. We're planning on launching in Nevada in mid-June and we also need your skills on the parachute release subsystem team, and on the robot "build" team (Obie and I.)
I'll look for an update from you on the forum. Please include an updated program.
Jake, I cut the wheel in half to make two thinner, lighter wheels. It worked like a charm. How the wheels will connect to the ASP-BOT remains the same.
Comments
Jake and Emily,
Paul's message (above) was, I believe, directed to you. When you reply please be sure to thank him for following along to see how our project is progressing, especially since he's in Spain. Then, read carefully and heed what he wrote. Don't get too far along with an idea that's not practical, or that's too complicated. As he said, using a solenoid may require more voltage than we have available and it may require additional and circuitry for the BOE. This is extra cost and work we don't necessarily need to do. "Simpler is better" in my estimation.
"What's the budget we have to work with?" you asked. "There is no budget", Mr. Kibler replies. The balance in our team account is $0.00 and so we need to be innovative. I'll buy what we need once I'm convinced that we really need it. I can also scrounge for materials from various and sundry places from time to time. "Necessity is the mother (or father) of invention" some say. In this case "Invention is the mother of necessity..."
========================================
Sylvie, mi amgio,
Como esta?! So you're in Espana? What a lucky guy. Are you in Andalucia? Madrid? The Pyrenees? I'll bet spring has come on full to the gold coast. How long have you been there? How's the calamari and sangri? You lucky guy. It's 27 degrees and the winds are 20 mph. It's cold out there!
Thanks for logging in Paul. Dylan and Andrew are getting to the point where they should be logging onto the forum seeking guidance. Andrew wrote and tested a subroutine for yesterday's practice that should activate the rover after it reads a certain number of consecutive 0's after landing. Figuring out where and how to intergarte it into the main program is their challenge and so I'm sure they would appreciate your and Tracy's help. I certainly do.
Send us a picture of 'Sylvie in Spain', why don't you? You can even gloat and say, "Wish you were here."
Safe travels,
Mark
:cool:
Jake and Emily,
As I just said in my previous post, I would read and heed Paul's sage advice..."
Mr. Kibler
At our last practice, we tried to accomplish adding a subroutine whose purpose was to call the movement subroutine after ten consecutive zeroes were read from the MAWD. We began by writing the subroutine so that when any altitude above 200 is reported by the MAWD, a movement subroutine would immediately start. However, the program consistently starts regardless of the altitude goal we set. Could you please take a look at the attached program code and assist us?
The only portion of the program of which we are unsure of is the fact that it depends on retrieving the current altitude from a variable labeled "feet." Although the comment where the variable is declared indicates that this variable should hold an integer equivalent to the altitude in feet, we are unable to determine this positively as we are confused on the MAWD subroutine itself functions, shown below.
MAWD_get: ' alternative code to acquire MAWD data, uses DEC5 instead of STR in SERIN PULSIN MAWDin,1,iobyte ' the purpose of this is to synchronize with the MAWD timing. PAUSE 10 ' this assures the SERIN will start waiting in the silent period before ' a MAWD xmission feet=0 SERIN MAWDin,84,64,MAWDnot,[DEC5 feet] MAWDnot: RETURNSpecifically, we are confused as to how the line "SERIN MAWDin,84,64,MAWDnot,[DEC5 feet]" functions. We have a primitive understanding of the SERIN command, but we were unable to determine how the rest of the functions work. We believe that better understanding this portion of the program will allow us to fix the problem in our new subroutine.
Another issue we are currently discussing is whether to use one or two BOE's. Because the I/O slots on the current BOE are all taken, except for one, and we plan on adding two servomotors in the near future, we figured that this would be our best option. In addition, we think that it will allow more data to be sampled as the STAMP is spending significantly less time moving the servo motors, and possibly calculating it's location, provided we meet our stretch goal of GPS-assisted navigation. What are your thoughts on both of these issues?
Thank you for your assistance,
Andrew and Dylan
Mr. Kibler- I've got a really good feeling about our new design. I understand what you're worried about, but to every question there is an answer. The prototype will be completed in two weeks. Also, This is un-ARLISS related, but do you ahve any recommandations for classes next year for me? There are so many!
Emily- We need to have one final conversation about design and then we can get into building it. Take heed of what Mr. Kibler is worried about the design. As he said, it is always good to have a back-up plan.
Obie- Below is a link to an interesting creation I found on the parallax website. Pay attention to the design, not the whole parallax board speech.
Here is the design you might be interested in. I believe it was brought up before:
http://forums.parallax.com/content.php
Thanks all,
-Jake-
Jake and Emily,
You may want to ask Paul if he has any ideas or suggestions for a simple and fail-safe parachute release mechanism. He's an advanced rocketeer, a clever and likeable guy, and he's launched lots of rockets. Really BIG rockets. Sometimes we have to learn to ask for advice even when we think our idea is "better." I'll bet he-- and others who follow along on the forum-- have some ideas for a simple parachute release mechanism that's not complicated and that's easy and affordable to build. All you have to do is ask.
RE: Selecting classes for next year, the first thing I would ask is, "Where do you want to go when you finish high school?" If you're looking toward engineering, take four years of science and all the math you can. If it's International Affairs, take as many language courses as you can. If you think you may be invited for the Honors Writing Prompt, prepare. I can show you how (Google "freshman honors writing prompt examples" for starters. There's also a time management component.) I'd be glad to meet with you, and your parents if you want, to help guide you along. Like the Knight Templar said in the movie, Indiana Jones and the Search For the Holy Grail, "Choose wisely." Your future depends on the choices you make: for better or for worse.
Mr. Kibler
:cool:
Some alternate ideas for a parachute deployment mechanism: Mechanically, Idea #1 is a simple device but it requires dual-deployment capability, which the MAWD has, and black powder. How we would get the parachute to detach ONLY after it has landed? Program the BOE to output an electric signal that ignites the black powder AFTER the ASP-BOT has landed, after it reads ten (twenty, etc.) 0's. Or send a signal from the BOE to heat up a wire that burns through the "string" holding the parachute. Other ideas...?
IDEA #1: http://www.apogeerockets.com/Tender_Descender.asp
IDEA #2 (use a servo and elastics...!) BE SURE TO WATCH THE VIDEO AT THE END http://sites.google.com/site/littlesquirtswaterrockets/parachute-systems/in-lineparachuterelease
IDEA#3: http://www.sierrafoxhobbies.com/catalog/product_info.php/products_id/1141?osCsid=bf0a29d9efd90221c01c31688a78e3cd
IDEA #4: http://www.knifecenter.com/kc_new/store_detail.html?s=VN33549
IDEA #5 (variation of #1): http://www.polartrec.com/expeditions/south-pole-ozone-changes/journals/december-8-and-9-weekend-the-south-pole
IDEA #6: http://aeroconsystems.com/cart/index.php?p=product&id=148&parent=49&is_print_version=true
I see two options for detaching the parachute after touchdown:
1) Program a servo to rotate "something" that releases the parachute (an elastic, etc.)
2) Program the BOE to heat up a wire that burns through monofilament (fishing line) holding the parachute.
Sylvie, what do you think? How would you rank these in order (1-5) from most practical to least practical?
How's Spain? I see that Barcelona beat Arsenal 3-1, a good win for the "home" team. Are you able to watch any football in Spain?
Mark
Sylvie- Again, like Mr. Kibler said, what are your ideas for a release mechanism that is simple yet effective and made from things we could salvage from home? Have a great time in Spain!
Thanks for all the help
-Jake-
Food for thought:
Idea #3 is attractive because it does have a plug-in similar to the servomotor's plug-in. Drawbacks:
1) Just because the device may connect to the BOE, is it compatible?
2) Where would we plug it in? Remember that we already have very limited input/output slots available and we need to free up two for the ASP-BOT (robot's) two motors.
3) The cost is 140 Euros. How much is that in dollars? Please convert this to USD ($$$) and post the price to the forum. Since the cost is in Euros the item is probably somewhere in Europe (England?) So there would be additional shipping cost (add 15-20 Euros.) It may take weeks to arrive from Europe. What if we buy it and we can't use it? This has happened in previous projects and the cost comes out of my pocket. Remember that basically we have no budget right now (*except what Mrs. K allows me to spend out of my allowance...!)
4) The "servo is activated by an altimeter - or similar device – by the Servo Control unit (not included), How do we make the MAWD (the altimeter) output a signal at '0' feet after it lands? Isn't the MAWD's input/output wire already being used to input altitude data to the BOE?
What about idea #2? It seems simple and I "think" we have all the parts we may need.
Andrew and Dylan, Please offer input since you are familar with how the ASP's circuitry works and Jake and Emily aren't. They need your input and guidance. We should be working as interdependent subsystem teams, not independently, with senior team members and the team captain overseeing and guiding the process.
Thanks,
Mr. Kibler
:cool:
You should be able to test your ¨do I know when I´ve landed?¨ routine by putting the MAWD into that vacuum bottle, running the wires out to your Stamp, and doing the ¨suck the air out¨ test. Of course that won´t be the real test - you´ll still need to keep your fingers crossed while you´re flying the thing. But it might flag some obvious problem in time for repair.
Hola Sylvie!
Bocadillas and bocarones and cerveza. What a life! You must be in near-heaven at 50 degrees after those wild Wisconsin winters. Spring is coming on slowly here after near-record snowfall. It feels very typically March here in Dunbarton. No bocadillas or bocarones, though micro-brew is on tap for this evening.
Tyler, who was on the ARLISS team the past two year and who is now at Swarthmore (early decision with scholarship) stopped by on Sunday while was home on spring break. He said, "What do you hear from Sylvie and Dr. Allen?" Now I can tell him (via his sister, a student of mine), "Sylvie is alive and well in Esapana!"
I don't think the Rocketeers have quite figured out the sequence of the program code to test it in the vaccum chamber yet. That's where they're stuck and that's where they're seeking input. The ASP-BOT will move and collect data at the same time, but not predictably. They're working on getting the code in the right order so we can test it in the vaccum chamber a week from Saturday. I'm not convinced they have the code 100% yet though, even if it happened to be in the correct sequence. But they are learning and moving ahead, much moreso than even last year.
Looks like we may well be aiming for a mid-June ARLISS launch-- two months to build and program. I was offered a position on faculty at King's Academy in Amman in August and I just may well do it! It's just a hop, skip and jump from Spain, you know. You're always welcome to stop in: here in NH, there in Jordan, wherever I happen to be.
Safe travels,
Mark
:cool:
I really like Mr Kibler's 2nd idea, its simple and elegant. Also it looks like there is less room for error then in our design, which could prove difficult to program.
Mr. Kibler, Thank you for the alternative ideas.
Sylvie, Thank you very much for checking in even when your in Spain, Have you scene what Jake and I are trying to make yet? Also do you have an ideas?
We (Jake and I) are going to replace the pneumatic actuator with a metal bar a servo motor, the servo motor will turn and push the bar and in turn the bar with push the two lever apart and the spring will send the disk that is attached to the parachute off. Again your thoughts would be greatly appreciated
Emily
Thanks all
-Jake-
first problem: Those rubber bands are very tightly stretched. What if they broke? We have to use something stronger.
Secondly: How would this attach to the parachute? in the picture it is attached to a solid object. How can you launch and object that is not being pulled downward originally?
I'm sure we can work these out.
Emily- The idea uses a servo. Can you work on the program for it? The prototype will be done for two weeks from now.
Merci,
-Jake-
Please work with your subsystem team partner on making the prototype. Use other team members-- Dylan, Andrew, Paul (Sylvie), etc.-- as a sounding board; ask for their advice before you get up to your ears in alligators (see photo below.) Alligators are not very friendly sometimes
(Alligators are, of course an analogy. Emily, what is an analogy? And Jake, what are the alligators an analogy for?) NOTE: No alligators were harmed in making this e-mail.
Mr. Kibler
:cool:
Emily- We should meet this weekend to work on the prototype!
-Jake-
Mr. Kibler, Analogy: drawing a comparison in order to show a similarity in some respect
Source: http://wordnetweb.princeton.edu/perl/webwn?s=analogy
Get well soon!
P.S. Jake- did you ever get my email? you didn't email me back so I don't know.
Emily
Emily,
Good for you for citing the source for your definition of 'analogy.' It's always proper to quote the source when you're using someone else's words or work.
I like the idea of Dylan joining you this weekend to help guide things along. He has a good overview of the project and he may think of seemingly small things that you and Jake may otherwise miss (for example, where will the parachute attach to the ASP-BOT so that it comes out of the tube free and clear? It can't really attach to a wheel, can it?) A three-person team always seems to work better than two.
Mr. Kibler
:cool:
Thanks for everything!
-Jake-
This seems like an analogy for an analogy. How does, "Don't get up your ears in alligators" relate to designing and building a parachute release mechanism...?
Mr. Kibler
Thanks
Emily
Mr. Kibler- Sorry about the analogy for an analogy, it's like a question for a question. I honostly don't know what the analogy means. Its on the tip of my tongue but I cant spit it out. That's why I answered with analogy, figuring maybe then the answer would come to me.
-Jake-
Case in point: Attached is a picture of a possible tire for the ASP-BOT. The good news is two-fold: 1) It fits perfectly inside the payload tube, and 2) It was free. I scrounged two of them from the junkyard (*the source of many free and excellent engineering materials.)
The downside is that it's heavy, maybe too heavy for the servos. It might drain too much voltage because of its weight. But they ARE made of solid rubber. I knocked the white plastic center out and what is left is the tread. We'll have to engineer a hub for the servos.
It would be easy for me to wed myself to the idea that "This is THE tire for the ASP-BOT", simply because it fits and because it was free. While those are considerations they shouldn't be the deciding factors in choosing the right tires. Does that make sense?
Obie (and others): What are your thoughts about using this tire? One of the first things we have to do Obie, is mount the servos and the tires on some sort of a platform. Then we'll lay out the circuitry loosely on the platform to see where things fit best. I'd like to hear your thoughts on the tire and on laying the circuitry out. Also, we need some sort of sturdy material for the platform, guys and gals. The platform is the wooden piece that everything is mounted on right now. I would rather not use wood. What about G10 fiberglass? Carbon fiber? What do you have at home that we might be able to use? Bring it to the next practice please
Finally, two people have contacted me about joining the team. If they're interested, the same guidelines apply to them that applied to you: three try-outs, a decision, and three missed practices allowed. Dylan, you may know one of them. His last name is St. Clair (or something like that) and I think he's from Henniker. He supposed to be a bright and capable kid. Andrew, the other is Justin Da Costa. Contact me by PM and let me know your thoughts.
Aim high,
Mr. Kibler
:cool:
Based on the specifications, it should be compatible with the Parallax servo motor. Remember, they are only selling an attachment which is in theory compatible with the type of servo motor Parallax sells.
Since this is an attachment, the only input/output slots required would be those required by the motor. That's still a lot of slots, if we are going to be using only one BOE.
The mechanism costs $193 US dollars, plus shipping. I think a safe estimate of the mechanism plus the cost of shipping would be about $220 US dollars. When I look at the cost of this device and compare it to it's effective functionality, I'm quite discouraged. I don't think we should completely remove this as a possibility, but it's a very pricey one. We should definitely investigate the alternatives first.
It is my understanding that the servo would be connected to the BOE, which already receives data from the MAWD. A new line would have to be added to the beginning of our movement subroutine to activate the servo that is connected to the mechanism.
-- Andrew
Rocketeers,
I hope that Andrew won't mind me sharing the good news with you. He was notified today that he was accepted for admission at Hawai'i Preparatory Academy in August and hearty CONGRATULATIONS are certainly in order! Andrew has worked VERY hard for this and he deserves a hearty pat on the back (or two!) It looks like we'd better get the ASP-BOT ready for a JUNE launch in Nevada... Congratulations Andrew!
Well done,
Mr. Kibler
Yes, that's right Andrew. I was hoping that you or Dylan would pick up on this. The signal to the servo (if we use one) would be an output from the BOE.
Aloha,
Mr. Kibler
One of the students interested in trying out for the team is Chase St. Laurent. If you know him, please e-mail me and fill me in.
mkibler@alumni.unity.edu
Are you meeting with Jake and Emily this weekend? Jake has some new insights to share with you now that he's seen the tire I'm proposing to use (see picture above.)
Thanks,
Mr. Kibler
:cool:
Today I got a chance to really study the new tires. The only problem is how are we going to put a release mechanism on this? Mr. Kibler and I have tried to think of numerous solutions, but they all seem to end with one problem or another. Any ideas? How about you Sylvie?
-Jake-
Jakester,
You have to give more specific information to people. For example, "...how are we going to put a release mechanism on this?" What does "this" refer to? Most people will have no idea. Add details. Be specific. Be clear.
Mr. Kibler
:cool:
secondly, by "this" I meant the wheel or the ASP-bot. "How are we going to put a release mechanism on the wheel or the ASP-bot withought ripping the wheel off our breaking anything? WE ahve no margin for error.
Have a good weekend!
-Jake-
Dylan and Andrew,
I would like an update on where the movement subroutine stands and how close you are to integrating it into the main program. I haven't seen any information about it on the forum for a while.
You have two goals for the next practice:1) Download your program, send the robot across the ground (indefinite distance), and collect temperature, humidity and CO2 data all at once.
This was a goal for last practice but I never did see the robot move with the program installed. That's why I gave you a BOE and servos,Dylan, and a BOE-BOT, Andrew: so you can figure the program out and get it working.
2) Dowload your program to last year's ASP, put it into the vacuum chamber, then see if your program will activate a servo AFTER the vacuum chamber returns to 1 ATM (= 1 atmosphere, or air pressure at ground level.)
Your goal for having your final program fully operational is four weeks from our next practice. We're planning on launching in Nevada in mid-June and we also need your skills on the parachute release subsystem team, and on the robot "build" team (Obie and I.)
I'll look for an update from you on the forum. Please include an updated program.
Jake, I cut the wheel in half to make two thinner, lighter wheels. It worked like a charm. How the wheels will connect to the ASP-BOT remains the same.
Obie and Emily, are you there...?
Mr. Kibler
:cool: