Justin,
How? Like so (see attached)?
How you get ("shoehorn") it in will depend on the dimensions of the matrials you choose, the compromises you have to strike, and so on. I'm sure you'll manage.
You're left designing after the fact, now, and that's where you start sweating bullets.
Realistically the payload bay in real life is a lot smaller than the one in the picture. In fact currently we are having to drill holes in the payload bay to make sure that when we put the ASP-BOT in it doesn't create a vacuum. Also the electronics decks are also only as large as the wheel(see attached). The attached picture is realistically how it sits in the payload tube.
There's a concise mech dwg. - you've quite the dilemma.
Does it then tend to pitch forward, in the direction of travel, or does it
wobbulate fore and aft?
PE - Maybe an alternate plan of motion? Run one servo "a" with servo "b" 'locked' and then run "b" with "a" 'locked'?
[I wouldn't have designed it like this. Welcome to the "wonderful world of solutions."]
In Engineering this is what they refer to as being "up a certain river."
Late 4/20 - Perhaps there's an issue of servo speed agreement, reading the MAWD ARLISS thread. Or a combination of this and design? As I alluded to previously, the asp-bot as constructed is like a Segway without the Segway's counterpoising ability. I'm not trying to be glib, just my surmise. That youtube-vid someone was going to do might help in diagnosing your predicament. I have only vague, subjective descriptions of the problem. :-|
My name is Naleli (Nah-lay-dee), and I go to school at Sant Bani School with Andre, Emily and Obie. They recommended I try out for the because they have noticed that I am interested in rocketry and I enjoy robotics and science (especially physics). I am very good at being practical and I am a good student who is very approachable as well as coachable. I look forward to meeting you all, as I have heard a lot about the group.
My name is Naleli (Nah-lay-dee), and I go to school at Sant Bani School with Andre, Emily and Obie. They recommended I try out for the because they have noticed that I am interested in rocketry and I enjoy robotics and science (especially physics). I am very good at being practical and I am a good student who is very approachable as well as coachable. I look forward to meeting you all, as I have heard a lot about the group.
Thank you,
Naleli
Naleli,
It's great to see that you took the time to post on the forum! It's wonderful to see that you are interested, so please stay tuned to the forum! Nearly all of the discussion outside of our practices occurs here. Although there is still much work to be done, our project will hopefully be nearing completion soon. I wont speak for Mr. Kibler or Dylan (our student project lead), but although it may be too late to join this project's team, you should consider visiting during one of our meetings to get a feel for the typical work incurred.
Mr. Kibler,
If you bring the bot to school, I could videotape it and post it so PJ can see how it exactly wobbles with and without the current stabilizer. Or I could stop by your house if you would like. It might be easier to analyze it anyway if we videotape it, in general. Give me a call at (603) 715-4522 or post if you would like me to do that. I'll use a better quality video than I did last time, when I post.
I am just recovering from my illness? The doctor said that if I engage in too much physical activity, or anything that will strain my lungs this week, I could be diagnosed with broncular pneumonia next week. So I still have to stay non-active, as I have for the last few days already. But I'm feeling alright for now.
I was just thinking about the stabilizer idea, and I am pretty sure I have found a solution. I'm sketching it up right now...
I reviewed my Idea for a while, and I realized that there would be interference between the stabilizers and some of the small components on the circuit board, just scrap that idea.
I am just recovering from my illness? The doctor said that if I engage in too much physical activity, or anything that will strain my lungs this week, I could be diagnosed with broncular pneumonia next week. So I still have to stay non-active, as I have for the last few days already. But I'm feeling alright for now.
I was just thinking about the stabilizer idea, and I am pretty sure I have found a solution. I'm sketching it up right now...
Dylan,
Glad to see that you're back in the land of the living again. The parachute release mechanism is our first priority right now, for two reasons:
1) If it doesn't work, the rover crashes into the ground from thousands of feet in the ai at 9.8 m/sec/sec. Not good.
2) The stabilizer mechanism works pretty well already.
Let's focus on the parachute release mechanism and let's be sure we have three or four ideas that might work, in case the first idea doesn't.
Thank you so much for the Help PJ!
Also Mr. Kibler, I'm confused, have we already created a solution or do we still need to build one of the other ideas mentioned?
Emily
... have we already created a solution or do we still need to build one of the other ideas mentioned?
Emily
A solution for which problem? Please clarify. If you mean a solution for the stabilizer, it's nearly done and it's not our first priroity. Jake and I will handle that at school.
If you mean a solution for the parachute release mechanism, then YES! We need a solution, and at least two back-up solutions for a parachute release mechanism in case the first idea doesn't work well. We'll test, test, test to be sure whichever idea we use works 100% predictably.
Justin, please continue to revise your "rod in the wheels" parachute deployment mechanism. We'll test both yours and Jake's idea and whichever works the best, we'll use. We need to get these prototypes done, tested, and installed on the rover.
Thanks to Everybody for the package you sent.
I appreciate all your cards and mementos (minerals, stickers, maple sugar, maple syrup, chocolates, and a rocket!)
I'm overwhelmed by your thoughtfulness.
I wish you every success. [Ad Astra Per Aspera]
Thanks again -- Andrew, Obie, Jake, Justin, Emily, and, last but not least, Mark!
A solution for which problem? Please clarify. If you mean a solution for the stabilizer, it's nearly done and it's not our first priroity. Jake and I will handle that at school.
If you mean a solution for the parachute release mechanism, then YES! We need a solution, and at least two back-up solutions for a parachute release mechanism in case the first idea doesn't work well. We'll test, test, test to be sure whichever idea we use works 100% predictably.
Justin, please continue to revise your "rod in the wheels" parachute deployment mechanism. We'll test both yours and Jake's idea and whichever works the best, we'll use. We need to get these prototypes done, tested, and installed on the rover.
Mr. Kibler
:cool:
Mr. Kibler,
I will be finished with me release mechanism as well for sunday. It will be small enough to fit anywhere in the bot and seems there will be no issue. The only concern I have is if the raw force of impact will be enough to activate it. I am now just scrambling to get the rest of the components I need. Hopefully this idea will be under consideration as well. ??? I noticed you did not mention it in your message above. :blank:
Thanks to Everybody for the package you sent.
I appreciate all your cards and mementos (minerals, stickers, maple sugar, maple syrup, chocolates, and a rocket!)
I'm overwhelmed by your thoughtfulness.
I wish you every success. [Ad Astra Per Aspera]
Thanks again -- Andrew, Obie, Jake, Justin, Emily, and, last but not least, Mark!
-- PJA --
PJ,
Not to sound trite or cliche, but it's the least we could do (and how about those trendy 'PJ' stickers?!) We are certainly overwhelmed by your thoughtfulness, too, and how you so unselfishly share your time and expertise. Thank you.
People working together, sharing friendship, expertise and goodwill sure makes the world a nicer place.
...the only concern I have is if the raw force of impact will be enough to activate it..
Chase,
I'm eager to see your device and I'm eager to get the parachute mechanism installed and operational. It's one of the last and certainly most important things remaining to do. I'm glad we have two or three different ideas (Jake's, Justin's, and yours) because I'm not 100% convinced that all three ideas will be 100% fail-safe.
Re: "the force of impact", does your idea assume an impact that pushes some sort of a "pin" (rod, lever, button)? If so, how do we ensure that the rover lands directly on the release "pin" every time? What if it's really windy and the rover lands at an angle...? Like you, I worry about the force of impact on the wheel. A high-speed landing at an angle could snap the spindle right off the servo/wheel.
Hi all-
First off, i'm sorry for not been online for the past week. I have however been working on the prototype even though making a new Lego stabilizer like the real one that we proposed has been troubling at the least. Currently I am just trying to find the "sweet spot" for the hook on this larger version. If you have on questions, concerns or comments, do say something
Chase- I'm glad to know you have another idea. It still has me a bit confused but I'm very excited to see it in person. I also am worried about the force impact on the wheel.
If we are worried about even holding the wheel, why bother even trying to land that? We need a solid way to reinforce the connection from the servo to the wheel. I have a possible solution, and is incorporated into the ASP-bot prototype.
I was in a meeting a couple of days ago with a NASA geologist who was just given a role on the Mars Science Laboratory mission, to launch around Thanksgiving and land on Mars next year. It's a rover vehicle about the size of a Mini Cooper. She was extremely nervous about how they're planning to land the thing, and this video will show you why:
Hi all-
First off, i'm sorry for not been online for the past week. I have however been working on the prototype even though making a new Lego stabilizer like the real one that we proposed has been troubling at the least. Currently I am just trying to find the "sweet spot" for the hook on this larger version. If you have on questions, concerns or comments, do say something
Chase- I'm glad to know you have another idea. It still has me a bit confused but I'm very excited to see it in person. I also am worried about the force impact on the wheel.
If we are worried about even holding the wheel, why bother even trying to land that? We need a solid way to reinforce the connection from the servo to the wheel. I have a possible solution, and is incorporated into the ASP-bot prototype.
Thanks again,
-Jake-
Jake,
I know we had discussed your idea in depth at the last meeting, and you had provided drawings of it to me. I was wondering how, if at all, your design has changed since then. Would it be worth uploading a new diagram to show others your design?
I'm also very curious as to what you are thinking you can do to reinforce the wheels. As you know, when we looked at that subject briefly, it seemed as there were very limited possibilities. I'm still unsure how this would be done without completely modifying the servo. Please post your ideas!
Andrew-
My design has not changed at all. In fact, it works great! the only problem is that I attempted to do a 1' drop onto a soft surface and the ASP-bot prototype fell apart. Do you have any ideas on how to reinforce the actual prototype itself?
My design for the strengthened wheel axle is hard to explain and diagram but I will try. In short, you take the weight off the main axle by adding other axles attached to a bar leading out from the main axle. If the main axle bends at all, the weight is distributed into the other axles. Thats a pretty vague explanation but I will have it fully operational on by sunday
The design I had for the parachute release does not work. The parachute is pulling on the release too much and it messes up the release mechanism on the way down. The pin mechanism is both getting pulled out before touchdown or getting caught. It unfortunately will not work as well as I had hoped. I will see if i can redesign it with a sharkbite piece my dad has in our basement that will hopefully get rid of the current issue i am having with this. The sharkbite, if you aren't familiar with it, is used in tubing for air cylinders and such so that it will grasp a tube or cylinder and not let go unless you push down on it. I can practically use the same design I had originally but use this component. I am very busy the next couple of days but I will see if I can still put this together. If not I will just bring in the sharkbite components and new sketch designs. If I dont get around to finishing it before the practice I would definately have it done during the week next week.
PJ - I'm glad you enjoyed the gifts, it was the least we could do.
Jake - I am sorry that your prototype broke but I am glad that it seems to be working.
Mr. Kibler - I have been working on an improved "rod in wheels" parachute release mechanism. I should be able to bring it to practice as long as I receive a new servo (which has been ordered) to replace the one my mom broke in a "drop test."
I was in a meeting a couple of days ago with a NASA geologist who was just given a role on the Mars Science Laboratory mission, to launch around Thanksgiving and land on Mars next year. It's a rover vehicle about the size of a Mini Cooper. She was extremely nervous about how they're planning to land the thing, and this video will show you why:
Mars Science Laboratory - Curiosity Rover - Mission Animation
I sure am eager to see the solution you guys come up with.
Hi Sylvie,
Thanks for the cool Mars Rover video link. It reminds me of an upscale version of our rover. What do you think of the "Curiosity's" deployment system in the video?
It seems overly complex, and risky. I wonder why they don't just bounce it onto the surface of Mars like they did with Spirit and Opportunity? Are they launching two rovers (almost) simultaneously like the did with the last Mars rovers? In any event it's a cool video. Thanks! It must have been awesome to work with the NASA geologist who's a 'primary' on the mission. Did you get front row seats for the launch?
The ASP-BOT rover, as you can see, is nearly finished. A few tweaks here and there and the rover itself is done. It's the parachute release mechanism I wonder and worry about. It has to be fail-safe or the whole sha-bang comes crashing to the desert floor at 9.8 m/sec (squared!) We have three prototypes that should appear at practice this Sunday. We'll scrutinize them and test them and then go with the one that works most predictably. If none of them work then it's back to the drawing board. I won't risk months of hard work by using an "iffy" prototype for our mission.
The Harvard SEDS project team all make their Level 1 certification launches this Saturday. We built generic 3" diameter x 42" rockets and we'll launch them all on H128W-M motors. I built one too, a silver 3" phenolic rocket that I named "Very Fast" (in the spirit of Harvard's motto. Think about it.) It looks like it may be windy on Saturday and so we built a dual deployment altimeter pod for insurance (powered by a MAWD, of course.)
I was in the airport last Friday and I happened to see Madrid playing "VAL" (Valencia?) in football on TV. It made me think of you and I smiled. Espana! Espana!
We would love to have you and PJ join us for the ARLISS launch on June 16-19. We can all bunk in my room at the Best Western - Fernely Inn (Nevada). Breakfast is included in the deal (and what a deal it is!) We arrive in Reno on Thursday the 16th and fly out on Sunday the 19th. Becky Green from Stanford/ARLISS is bringing a new 9' tall rocket. She's launching it on quad L's with an air-start "M". It should be quite a show!
I haven't posted for a while but the parachute release on the curiousity rover was really cool for sure. I remember a few weeks a go that one one my mission goals is to create a launch prep procedure so I have a basic one for that, might need a little editing though. I have to go to church now. See ya all soon.
In a quick post I just want to stress the importance of getting these procedures done. Last year, as Andrew and Mr. Kibler can recall, the result of not getting all the procedures done caused what should of taken 3 hours to take over 6 hours. I feel that getting these procedures done is not to far behind the importance of getting the parachute release mechanism to work. Both can render our team cold in our tracks if not completed
Thanks for the cool Mars Rover video link. It reminds me of an upscale version of our rover. What do you think of the "Curiosity's" deployment system in the video?
It seems overly complex, and risky. I wonder why they don't just bounce it onto the surface of Mars like they did with Spirit and Opportunity? Are they launching two rovers (almost) simultaneously like the did with the last Mars rovers? In any event it's a cool video. Thanks! It must have been awesome to work with the NASA geologist who's a 'primary' on the mission. Did you get front row seats for the launch?
They're not bouncing it simply because it's too big - it's the size of a Mini Cooper, by her description. And there's only one of it.
I imagine she could get me into a better seat than I could get myself for the launch - I've still never seen one close up, though I did see a Delta launch from Melbourne (in FL) once.
The ASP-BOT rover, as you can see, is nearly finished. A few tweaks here and there and the rover itself is done. It's the parachute release mechanism I wonder and worry about. It has to be fail-safe or the whole sha-bang comes crashing to the desert floor at 9.8 m/sec (squared!) We have three prototypes that should appear at practice this Sunday. We'll scrutinize them and test them and then go with the one that works most predictably. If none of them work then it's back to the drawing board. I won't risk months of hard work by using an "iffy" prototype for our mission.
Parachute release is difficult. When the Space Grant Consortium contest a few years ago had rovers, there were several chutes tangled around vehicles, around axles, failure to release.
That reminds me - this Saturday is this year's launch, supposedly with steerable parachutes again. I'll let you know what happens.
Sorry I have been so little help here with your group - I've been FAR busier than normal this semester.
The Harvard SEDS project team all make their Level 1 certification launches this Saturday. We built generic 3" diameter x 42" rockets and we'll launch them all on H128W-M motors. I built one too, a silver 3" phenolic rocket that I named "Very Fast" (in the spirit of Harvard's motto. Think about it.) It looks like it may be windy on Saturday and so we built a dual deployment altimeter pod for insurance (powered by a MAWD, of course.)
I did see that in the emails. I don't think you're going to need dual deploy on 3" rockets flying on H128s, though, unless your field is really small. But it'd be fun to do anyway.
We would love to have you and PJ join us for the ARLISS launch on June 16-19. We can all bunk in my room at the Best Western - Fernely Inn (Nevada). Breakfast is included in the deal (and what a deal it is!) We arrive in Reno on Thursday the 16th and fly out on Sunday the 19th. Becky Green from Stanford/ARLISS is bringing a new 9' tall rocket. She's launching it on quad L's with an air-start "M". It should be quite a show!
I'd always love to come, but as usual, it's impossible. I'm going out of town to see the Brewers play the Red Sox in Boston, at Fenway, exactly those days.
I'd always love to come, but as usual, it's impossible. I'm going out of town to see the Brewers play the Red Sox in Boston, at Fenway, exactly those days.
Paul
...and of course we'll be in Nevada while you're at the Sox game. That's too bad since we're less than an hour north of Boston. It would have been great to connect and I could have picked you up at the airport and introduced you to the folks at Harvard/SEDS.
You've actually been very helpful with this year's project.
I have an idea that might work. What if the notch in one wheel went over the rod one way (clockwise) with the notch in the other wheel going in the other direction (counterclockwise)? That way both wheels would hold the parachute release bolt from opposite directions, something like twisting a lid onto a jar.
We would have to program each wheel to move separately after the rover lands to align the slots in the wheel. One wheel would be programmed to turn (for example) 1/2 turn clockwise and the other would turn 1/2 turn counterclockwise, "unlocking" the bolt. Then both wheels would be programmed to move in the same direction (like you have it programmed now), releasing or "kicking" the bolt out (like it does now.)
The next time we meet we'll mount another servo horn on the opposite side of one wheel to test the idea (the wheel will have one servo horn on each side.) If you have another servo horn at home, please try the idea and then report your findings to everyone on the forum. The idea may or may not work but it has merit. I'll look for your report on the forum.
Mr. Kibler- We talked over this idea in class and I agree that it sounds fairly fail proof. And again I will bring up the point that during Justin's trails, if one wheel only turned, the bar would still slide out of the groove. We would have to make the bar "stationary" in one wheel while the other is turning.
All- Tell me what you think of this, but I think it would be in our best interest to really work hard on Justin's idea and Chase's idea, and then have mine worked one less but still worked on as a back-up in case something goes wrong with the other two.
Chase- I'm very curious on the shark-bite prototype. Is it operational? Please ask questions and give comments so we all can help!
Hi all again-
There wasn't much conversation this weekend and I felt there should definitely been more after Mr. Kibler's and my post. What do you all think about it? We are at a crucial point and need to continue strong until the trip is over. As Mr. Kibler says, "work needs to get done outside of practice as well. Sorry to have to bring this up but it is very important we continue to talk and work on ideas (mostly parachute designs)
Justin- Are you free Thursday? I would like to work on your design with you if that is okay. Run it through some simple tests.
Comments
How? Like so (see attached)?
How you get ("shoehorn") it in will depend on the dimensions of the matrials you choose, the compromises you have to strike, and so on. I'm sure you'll manage.
You're left designing after the fact, now, and that's where you start sweating bullets.
Realistically the payload bay in real life is a lot smaller than the one in the picture. In fact currently we are having to drill holes in the payload bay to make sure that when we put the ASP-BOT in it doesn't create a vacuum. Also the electronics decks are also only as large as the wheel(see attached). The attached picture is realistically how it sits in the payload tube.
Justin
Does it then tend to pitch forward, in the direction of travel, or does it
wobbulate fore and aft?
PE - Maybe an alternate plan of motion? Run one servo "a" with servo "b" 'locked' and then run "b" with "a" 'locked'?
[I wouldn't have designed it like this. Welcome to the "wonderful world of solutions."]
In Engineering this is what they refer to as being "up a certain river."
Late 4/20 - Perhaps there's an issue of servo speed agreement, reading the MAWD ARLISS thread. Or a combination of this and design? As I alluded to previously, the asp-bot as constructed is like a Segway without the Segway's counterpoising ability. I'm not trying to be glib, just my surmise. That youtube-vid someone was going to do might help in diagnosing your predicament. I have only vague, subjective descriptions of the problem. :-|
My name is Naleli (Nah-lay-dee), and I go to school at Sant Bani School with Andre, Emily and Obie. They recommended I try out for the because they have noticed that I am interested in rocketry and I enjoy robotics and science (especially physics). I am very good at being practical and I am a good student who is very approachable as well as coachable. I look forward to meeting you all, as I have heard a lot about the group.
Thank you,
Naleli
Naleli,
It's great to see that you took the time to post on the forum! It's wonderful to see that you are interested, so please stay tuned to the forum! Nearly all of the discussion outside of our practices occurs here. Although there is still much work to be done, our project will hopefully be nearing completion soon. I wont speak for Mr. Kibler or Dylan (our student project lead), but although it may be too late to join this project's team, you should consider visiting during one of our meetings to get a feel for the typical work incurred.
Thanks,
Andrew
If you bring the bot to school, I could videotape it and post it so PJ can see how it exactly wobbles with and without the current stabilizer. Or I could stop by your house if you would like. It might be easier to analyze it anyway if we videotape it, in general. Give me a call at (603) 715-4522 or post if you would like me to do that. I'll use a better quality video than I did last time, when I post.
Justin
I am just recovering from my illness? The doctor said that if I engage in too much physical activity, or anything that will strain my lungs this week, I could be diagnosed with broncular pneumonia next week. So I still have to stay non-active, as I have for the last few days already. But I'm feeling alright for now.
I was just thinking about the stabilizer idea, and I am pretty sure I have found a solution. I'm sketching it up right now...
Dylan,
Glad to see that you're back in the land of the living again. The parachute release mechanism is our first priority right now, for two reasons:
1) If it doesn't work, the rover crashes into the ground from thousands of feet in the ai at 9.8 m/sec/sec. Not good.
2) The stabilizer mechanism works pretty well already.
Let's focus on the parachute release mechanism and let's be sure we have three or four ideas that might work, in case the first idea doesn't.
Mr. Kibler
:cool:
Also Mr. Kibler, I'm confused, have we already created a solution or do we still need to build one of the other ideas mentioned?
Emily
A solution for which problem? Please clarify. If you mean a solution for the stabilizer, it's nearly done and it's not our first priroity. Jake and I will handle that at school.
If you mean a solution for the parachute release mechanism, then YES! We need a solution, and at least two back-up solutions for a parachute release mechanism in case the first idea doesn't work well. We'll test, test, test to be sure whichever idea we use works 100% predictably.
Justin, please continue to revise your "rod in the wheels" parachute deployment mechanism. We'll test both yours and Jake's idea and whichever works the best, we'll use. We need to get these prototypes done, tested, and installed on the rover.
Mr. Kibler
:cool:
I appreciate all your cards and mementos (minerals, stickers, maple sugar, maple syrup, chocolates, and a rocket!)
I'm overwhelmed by your thoughtfulness.
I wish you every success. [Ad Astra Per Aspera]
Thanks again -- Andrew, Obie, Jake, Justin, Emily, and, last but not least, Mark!
-- PJA --
Mr. Kibler,
I will be finished with me release mechanism as well for sunday. It will be small enough to fit anywhere in the bot and seems there will be no issue. The only concern I have is if the raw force of impact will be enough to activate it. I am now just scrambling to get the rest of the components I need. Hopefully this idea will be under consideration as well. ??? I noticed you did not mention it in your message above. :blank:
Thanks,
Chase
PJ,
Not to sound trite or cliche, but it's the least we could do (and how about those trendy 'PJ' stickers?!) We are certainly overwhelmed by your thoughtfulness, too, and how you so unselfishly share your time and expertise. Thank you.
People working together, sharing friendship, expertise and goodwill sure makes the world a nicer place.
Best (from Ohio),
E. Bunny
:cool:
Chase,
I'm eager to see your device and I'm eager to get the parachute mechanism installed and operational. It's one of the last and certainly most important things remaining to do. I'm glad we have two or three different ideas (Jake's, Justin's, and yours) because I'm not 100% convinced that all three ideas will be 100% fail-safe.
Re: "the force of impact", does your idea assume an impact that pushes some sort of a "pin" (rod, lever, button)? If so, how do we ensure that the rover lands directly on the release "pin" every time? What if it's really windy and the rover lands at an angle...? Like you, I worry about the force of impact on the wheel. A high-speed landing at an angle could snap the spindle right off the servo/wheel.
From Ohio,
Mr. Kibler
:cool:
First off, i'm sorry for not been online for the past week. I have however been working on the prototype even though making a new Lego stabilizer like the real one that we proposed has been troubling at the least. Currently I am just trying to find the "sweet spot" for the hook on this larger version. If you have on questions, concerns or comments, do say something
Chase- I'm glad to know you have another idea. It still has me a bit confused but I'm very excited to see it in person. I also am worried about the force impact on the wheel.
If we are worried about even holding the wheel, why bother even trying to land that? We need a solid way to reinforce the connection from the servo to the wheel. I have a possible solution, and is incorporated into the ASP-bot prototype.
Thanks again,
-Jake-
http://www.nasa.gov/multimedia/videogallery/index.html?collection_id=18895&media_id=78187681
Mars Science Laboratory - Curiosity Rover - Mission Animation
I sure am eager to see the solution you guys come up with.
Jake,
I know we had discussed your idea in depth at the last meeting, and you had provided drawings of it to me. I was wondering how, if at all, your design has changed since then. Would it be worth uploading a new diagram to show others your design?
I'm also very curious as to what you are thinking you can do to reinforce the wheels. As you know, when we looked at that subject briefly, it seemed as there were very limited possibilities. I'm still unsure how this would be done without completely modifying the servo. Please post your ideas!
Andrew
My design has not changed at all. In fact, it works great! the only problem is that I attempted to do a 1' drop onto a soft surface and the ASP-bot prototype fell apart. Do you have any ideas on how to reinforce the actual prototype itself?
My design for the strengthened wheel axle is hard to explain and diagram but I will try. In short, you take the weight off the main axle by adding other axles attached to a bar leading out from the main axle. If the main axle bends at all, the weight is distributed into the other axles. Thats a pretty vague explanation but I will have it fully operational on by sunday
thanks again,
-Jake-
The design I had for the parachute release does not work. The parachute is pulling on the release too much and it messes up the release mechanism on the way down. The pin mechanism is both getting pulled out before touchdown or getting caught. It unfortunately will not work as well as I had hoped. I will see if i can redesign it with a sharkbite piece my dad has in our basement that will hopefully get rid of the current issue i am having with this. The sharkbite, if you aren't familiar with it, is used in tubing for air cylinders and such so that it will grasp a tube or cylinder and not let go unless you push down on it. I can practically use the same design I had originally but use this component. I am very busy the next couple of days but I will see if I can still put this together. If not I will just bring in the sharkbite components and new sketch designs. If I dont get around to finishing it before the practice I would definately have it done during the week next week.
Thanks,
Chase St. Laurent
PJ - I'm glad you enjoyed the gifts, it was the least we could do.
Jake - I am sorry that your prototype broke but I am glad that it seems to be working.
Mr. Kibler - I have been working on an improved "rod in wheels" parachute release mechanism. I should be able to bring it to practice as long as I receive a new servo (which has been ordered) to replace the one my mom broke in a "drop test."
Justin
Don't be sorry that it broke! Every crash is a lesson. Now I know that I need to reinforce the actual ASP-bot prototype.
Thanks,
-Jake-
Hi Sylvie,
Thanks for the cool Mars Rover video link. It reminds me of an upscale version of our rover. What do you think of the "Curiosity's" deployment system in the video?
http://www.nasa.gov/multimedia/videogallery/index.html?collection_id=18895&media_id=78187681
It seems overly complex, and risky. I wonder why they don't just bounce it onto the surface of Mars like they did with Spirit and Opportunity? Are they launching two rovers (almost) simultaneously like the did with the last Mars rovers? In any event it's a cool video. Thanks! It must have been awesome to work with the NASA geologist who's a 'primary' on the mission. Did you get front row seats for the launch?
The ASP-BOT rover, as you can see, is nearly finished. A few tweaks here and there and the rover itself is done. It's the parachute release mechanism I wonder and worry about. It has to be fail-safe or the whole sha-bang comes crashing to the desert floor at 9.8 m/sec (squared!) We have three prototypes that should appear at practice this Sunday. We'll scrutinize them and test them and then go with the one that works most predictably. If none of them work then it's back to the drawing board. I won't risk months of hard work by using an "iffy" prototype for our mission.
The Harvard SEDS project team all make their Level 1 certification launches this Saturday. We built generic 3" diameter x 42" rockets and we'll launch them all on H128W-M motors. I built one too, a silver 3" phenolic rocket that I named "Very Fast" (in the spirit of Harvard's motto. Think about it.) It looks like it may be windy on Saturday and so we built a dual deployment altimeter pod for insurance (powered by a MAWD, of course.)
I was in the airport last Friday and I happened to see Madrid playing "VAL" (Valencia?) in football on TV. It made me think of you and I smiled. Espana! Espana!
We would love to have you and PJ join us for the ARLISS launch on June 16-19. We can all bunk in my room at the Best Western - Fernely Inn (Nevada). Breakfast is included in the deal (and what a deal it is!) We arrive in Reno on Thursday the 16th and fly out on Sunday the 19th. Becky Green from Stanford/ARLISS is bringing a new 9' tall rocket. She's launching it on quad L's with an air-start "M". It should be quite a show!
Mark
:cool:
Obie
They're not bouncing it simply because it's too big - it's the size of a Mini Cooper, by her description. And there's only one of it.
I imagine she could get me into a better seat than I could get myself for the launch - I've still never seen one close up, though I did see a Delta launch from Melbourne (in FL) once.
Parachute release is difficult. When the Space Grant Consortium contest a few years ago had rovers, there were several chutes tangled around vehicles, around axles, failure to release.
That reminds me - this Saturday is this year's launch, supposedly with steerable parachutes again. I'll let you know what happens.
Sorry I have been so little help here with your group - I've been FAR busier than normal this semester.
I did see that in the emails. I don't think you're going to need dual deploy on 3" rockets flying on H128s, though, unless your field is really small. But it'd be fun to do anyway.
I'd always love to come, but as usual, it's impossible. I'm going out of town to see the Brewers play the Red Sox in Boston, at Fenway, exactly those days.
Paul
...and of course we'll be in Nevada while you're at the Sox game. That's too bad since we're less than an hour north of Boston. It would have been great to connect and I could have picked you up at the airport and introduced you to the folks at Harvard/SEDS.
You've actually been very helpful with this year's project.
Mark
:cool:
I have an idea that might work. What if the notch in one wheel went over the rod one way (clockwise) with the notch in the other wheel going in the other direction (counterclockwise)? That way both wheels would hold the parachute release bolt from opposite directions, something like twisting a lid onto a jar.
We would have to program each wheel to move separately after the rover lands to align the slots in the wheel. One wheel would be programmed to turn (for example) 1/2 turn clockwise and the other would turn 1/2 turn counterclockwise, "unlocking" the bolt. Then both wheels would be programmed to move in the same direction (like you have it programmed now), releasing or "kicking" the bolt out (like it does now.)
The next time we meet we'll mount another servo horn on the opposite side of one wheel to test the idea (the wheel will have one servo horn on each side.) If you have another servo horn at home, please try the idea and then report your findings to everyone on the forum. The idea may or may not work but it has merit. I'll look for your report on the forum.
What do others think of this idea...?
Mr. Kibler
:cool:
All- Tell me what you think of this, but I think it would be in our best interest to really work hard on Justin's idea and Chase's idea, and then have mine worked one less but still worked on as a back-up in case something goes wrong with the other two.
Chase- I'm very curious on the shark-bite prototype. Is it operational? Please ask questions and give comments so we all can help!
thanks again,
-Jake-
There wasn't much conversation this weekend and I felt there should definitely been more after Mr. Kibler's and my post. What do you all think about it? We are at a crucial point and need to continue strong until the trip is over. As Mr. Kibler says, "work needs to get done outside of practice as well. Sorry to have to bring this up but it is very important we continue to talk and work on ideas (mostly parachute designs)
Justin- Are you free Thursday? I would like to work on your design with you if that is okay. Run it through some simple tests.
Thanks again,
-Jake-