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Cheif Operations Director
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HebaruSan

HebaruSan

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1 minute ago, Cheif Operations Director said:

How could I start smaller for a guidance system other than turn motors for 1.3 seconds and then free fly

"Start smaller" means to do a different, easier project first, one that still has some similarity to your final vision. For example, you could try making an artificial plant stem that tilts itself towards light sources along one axis. This would be easier in that it sits still, only needs to worry about one spatial axis, and relies only on very simple logic, but you would still have to figure out how to set up the tiny computer, how to handle input from sensors, how to drive servos, etc. Once you've finished something like that, taking on a rocket guidance system would be more feasible.

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Cheif Operations Director

Cheif Operations Director

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3 minutes ago, HebaruSan said:

"Start smaller" means to do a different, easier project first, one that still has some similarity to your final vision. For example, you could try making an artificial plant stem that tilts itself towards light sources along one axis. This would be easier in that it sits still, only needs to worry about one spatial axis, and relies only on very simple logic, but you would still have to figure out how to set up the tiny computer, how to handle input from sensors, how to drive servos, etc. Once you've finished something like that, taking on a rocket guidance system would be more feasible.

what is the difference. the guidance and SAS system will be completely separate. their are only 4 sensors. I'm buying a completely separate telemetry system already

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DerekL1963

DerekL1963

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1 hour ago, Cheif Operations Director said:

what is the difference. the guidance and SAS system will be completely separate.


I think that you're monstrously confused here.   Guidance and stability control (and whatever you're using for attitude reference) are intimately related.  Not the least because the signals from the first have to be mathematically combined with the signals from the second to derive a single control signal for whatever you're using for thrust vector control.  And that's setting aside the fact that thrust vector control is a very complicated problem in it's own right.  Heck, the problem of properly mixing the signals and deriving a combined control signal is very much a non-trivial problem.

No offense, the basic problem here runs much deeper than not knowing anything about controllers and how to program them...  You don't even have a good handle on the problem domain. let alone the difficulty of the overall project.

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Shpaget

Shpaget

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What sort of a rocket are we talking about?

Pretty much every amateur rocket I've seen in real life has a burn time of about one second or less. While for a computer one second is an eternity, there is only so much you can do with control surfaces in that time. Better not touch them at all and make sure you rocket is stable by itself. 

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Cheif Operations Director

Cheif Operations Director

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2 hours ago, DerekL1963 said:


I think that you're monstrously confused here.   Guidance and stability control (and whatever you're using for attitude reference) are intimately related.  Not the least because the signals from the first have to be mathematically combined with the signals from the second to derive a single control signal for whatever you're using for thrust vector control.  And that's setting aside the fact that thrust vector control is a very complicated problem in it's own right.  Heck, the problem of properly mixing the signals and deriving a combined control signal is very much a non-trivial problem.

No offense, the basic problem here runs much deeper than not knowing anything about controllers and how to program them...  You don't even have a good handle on the problem domain. let alone the difficulty of the overall project.

No I understand that, the My "guidance system" will be a soft ware version of the V1, atleast similar it will do a certain perimeter Ex: Motors turn for 1.3 seconds and then the "SAS" will only keep it from not flying off from the wind. It isn't supposed to keep it on a set flight profile. I could care less about small deviations. 

2 hours ago, PakledHostage said:

Or a develop a model rocket control system...

Atleast I had to get taught it 

3 minutes ago, Shpaget said:

What sort of a rocket are we talking about?

Pretty much every amateur rocket I've seen in real life has a burn time of about one second or less. While for a computer one second is an eternity, there is only so much you can do with control surfaces in that time. Better not touch them at all and make sure you rocket is stable by itself. 

It will have a burn time of atleast 5 seconds. 

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DerekL1963

DerekL1963

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1 minute ago, Cheif Operations Director said:

No I understand that, the My "guidance system" will be a soft ware version of the V1, atleast similar it will do a certain perimeter Ex: Motors turn for 1.3 seconds and then the "SAS" will only keep it from not flying off from the wind. It isn't supposed to keep it on a set flight profile. I could care less about small deviations. 


You do realize that "keeping from not flying off from the wind" and "not caring about small deviations" are mutually incompatible statements?  Not to mention keeping it "not flying off from the wind" (keeping it on a flight profile) is a guidance function, not a stability control function.  Just like SAS in KSP, the rocket steers until it reaches the desired attitude (as determined by the guidance function) and then stability control keeps it there.   The two functions (stability control and guidance) are intimately bound together.  And that's not even getting into the flight control function, which takes the output of the guidance and stability functions and translates them into actual hardware commands.  Non trivial, not the least of which because you may have to correct the commands for roll orientation - possibly while correcting roll orientation.

This isn't plug-and-play Estes (or even Cesaroni or the like) level rocketry.  (Their burn time, and thus effective control time, is too short.)  This is serious high level rocketry.

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Cheif Operations Director

Cheif Operations Director

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2 hours ago, DerekL1963 said:


You do realize that "keeping from not flying off from the wind" and "not caring about small deviations" are mutually incompatible statements?  Not to mention keeping it "not flying off from the wind" (keeping it on a flight profile) is a guidance function, not a stability control function.  Just like SAS in KSP, the rocket steers until it reaches the desired attitude (as determined by the guidance function) and then stability control keeps it there.   The two functions (stability control and guidance) are intimately bound together.  And that's not even getting into the flight control function, which takes the output of the guidance and stability functions and translates them into actual hardware commands.  Non trivial, not the least of which because you may have to correct the commands for roll orientation - possibly while correcting roll orientation.

This isn't plug-and-play Estes (or even Cesaroni or the like) level rocketry.  (Their burn time, and thus effective control time, is too short.)  This is serious high level rocketry.

Ok here is what I mean: I'm going to have 4 fins they are going to move in a certain time period. The SAS will just fire thrusters and sensors. 

I mean in MY rocket they will be separate systems. SAS will have no idea where it is. It will just counter wind. The guidance systems is very simple just a turn motor for xyz time program.

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DerekL1963

DerekL1963

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43 minutes ago, Cheif Operations Director said:

I mean in MY rocket they will be separate systems. SAS will have no idea where it is. It will just counter wind. The guidance systems is very simple just a turn motor for xyz time program.


Stability control maintains attitude, it does not control trajectory ("counter wind").  Guidance controls trajectory.  And to do so it has to know at least the rudiments of where it is - it can't counter the wind if it can't detect that the wind has affected trajectory.  Flight control takes the output from stability control and guidance and generates the actual hardware commands.  These are inseparable functions.

Your control problem is going to be much worse if you have a separate set of controls operated automatically.   How are you going to prevent one set from work in opposition to the other?

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Cheif Operations Director

Cheif Operations Director

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2 hours ago, DerekL1963 said:


Stability control maintains attitude, it does not control trajectory ("counter wind").  Guidance controls trajectory.  And to do so it has to know at least the rudiments of where it is - it can't counter the wind if it can't detect that the wind has affected trajectory.  Flight control takes the output from stability control and guidance and generates the actual hardware commands.  These are inseparable functions.

Your control problem is going to be much worse if you have a separate set of controls operated automatically.   How are you going to prevent one set from work in opposition to the other?

If a sensor is triggered then is sends a signal and fires a thruster.

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Cheif Operations Director

Cheif Operations Director

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1 minute ago, HebaruSan said:

The main mistake you've been making is to ask for advice and help and then to argue with the advice and help that you receive instead of taking it on board.

Again how is relation to rocketry could I make it simpler, I would love to make it simplifier seeing as I can't even write one working line of code.

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steve_v

steve_v

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Just now, Cheif Operations Director said:

how is relation to rocketry could I make it simpler

You can't. Rocket science is complicated.
A certain minimum complexity is required for the system to work properly, if you really want to do this you will have to learn.
"I want to do [coding related thing] but I don't want to learn to code" is a common and annoying request. People give up answering such questions quickly.

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Cheif Operations Director

Cheif Operations Director

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1 minute ago, steve_v said:

You can't. Rocket science is complicated.
A certain minimum complexity is required for the system to work properly, if you really want to do this you will have to learn.
"I want to do [coding related thing] but I don't want to learn to code" is a common and annoying request. People give up answering such questions quickly.

I know that's my point I keep getting told make it simpler yet but I skimpily can't make it simpler than an if A is triggered do B system. 

I could easily do this in drag and drop code in less than an hour. 

Atleast the basics outline. Not including bugs

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Green Baron

Green Baron

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I try :-)

If you are in front of a programming project you must first identify your problem. Then you break it down into components that you can each handle separately.

You haven't yet done so, not even given the components of your problem. "Is there a drag and drop python program to control a rocket" does not address the problem. First, Python is not the right tool for the job, second, if the toy rocket manufacturer doesn't offer such a thing then this is for a reason (all the hard- and software would make it too expensive and a radio relay needs certification).

I give you an example out of my fantasy, i do not claim that this is real:

Wish: I want to control a rocket ascent. I have a rocket that has a fixed motor that can be started and then burns with a thrust for a time. In that time the rocket mass goes from a to b and the acceleration from x to y. I neglect any atmosphere.

For that, to get a number for the actual climb rate and acceleration the rocket needs a timer that starts at motor start. From the timer, with the initial information, current mass and acceleration can be calculated. Furthermore, it needs something to tell it in what direction it is facing (GPS can't do that, there is no time in the short flight, a gyro would), actuators and position sensors for the fins and some modeling of how the fins affect the course.

A microprocessor program must integrate the values. It needs readings from gyro, sensors, control of the actuators and an internal model of the flight to fell the right decisions.

Tools: Since the flight is short (seconds) it must be fast, like 100s of loops per second of read out, crunching and sending to the actuators as well as feedback with the gyro. And it must be lean since we can't take a full operating system on every flight when half of them are doomed to end up in a pond or on the rocks. Which brings us to C and Assembler, the typical tools for microcontroller programming.

Which brings me back to the initial question: it can't be answered that easily, if you want to get into coding start with C. It is free, straightforward, doesn't overwhelm you with data structures, i/o and libraries (in the beginning) and you are sure to do things right from start or they won't work.

:-)

 

Edited by Green Baron
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FleshJeb

FleshJeb

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Practice in KSP first. https://krpc.github.io/krpc/. Follow the "getting started" guide, and the excellent tutorials.

The guide tells you how to install Python (a real-world programming language).

Python ALSO runs on some Raspberry Pi and Gumstix models, which both have good form-factors for fitting into a model rocket.

The SAS built into KSP is already quite "smart", because it runs in a simulation and not the real world. It already knows where it is and where it's heading. However, it will allow you to play with your ideas in the same language that you'd use on a real model rocket.

EDIT: I got ninja'd by Green Baron :D

Edited by FleshJeb
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steve_v

steve_v

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1 hour ago, FleshJeb said:

Raspberry Pi and Gumstix models, which both have good form-factors for fitting into a model rocket.

Eh? Isn't a Pi a bit overkill for a model rocket? I'd use the smallest, cheapest micro that will run guidance fast enough and has sufficient I/O.
Why launch unnecessary hardware just to run a high-level language like python? You're probably going to drop it in a lake anyway. Inefficient.
 

9 hours ago, Cheif Operations Director said:

I could easily do this in drag and drop code in less than an hour. 

"drag-and-drop" is just a lazy excuse to not learn to code. I don't know of any such interface to a real microcontroller, which is what you want on a rocket. The Arduino IDE is pretty easy to use though.
Arduino micro or mini, some micro servos, an accelerometer, battery & voltage regulator, a bit of C = DIY guided missile. You might even get lucky and find some schematics and code you can adapt on the 'net, I'm sure this has been done before.
The thing holding you up is your insistence that it needs to be "drag and drop" and "no coding". Unless some company makes a toy rocket with a toy programming interface, this is fantasy.

Edited by steve_v
Just noticed a stray "l", dunno how that got in there.
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FleshJeb

FleshJeb

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On 3/14/2018 at 3:23 AM, steve_v said:

Eh? Isn't a Pi a bit overkill for a model rocket? I'd use the smallest, cheapest micro that will run guidance fast enough and has sufficient I/O.
Why launch unnecessary hardware just to run a high-level language like python? You're probably going to drop it in a lake anyway. Inefficient.

I have an ulterior motive for suggesting that course of action in that order.

Edited by FleshJeb
I was rude, and it was un-called for.
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