As a uni placement student I wrote a full screen 'analogue' clock display.
on IBM system/36 attached greenscreen terminals (of various types).
Using RPG II and the SDA...not really designed for animated graphics, but it worked !
27 posts • joined 17 May 2012
'Airlines should be able to assume that a plane they plan on ordering is fully functional and safe;'
Yes, but I assume that 'indicator that all is not well with the sensor data' is there to cover a faulty sensor that was functional and safe when the aircraft was certified, but that got bent or worn out in service.
Some years ago my father upgraded from his old cuboid shaped Apple Mac to a new mushroom shaped Apple mac. He assembled it and then found a problem ... how do you turn in ON ?
He called me in and It took me ages to work it out - including reading the manuals.
Old Apple computer had a power key on the keyboard. New Applce computer did not. Had no similar marked keys ... had no obvious key combination of 'command'+enter etc...
New Apple did not have any obvious power button or switch - on the base, screen support stem or screen.
The OLD way was a large rectangular button on the top corner of the keyboard with a 'play' style triangle on it.
The NEW way to power it on was a tiny round white button flush with the white casing marked with the ISO? 'O/I' embossed symbol ... on the BACK of the base unit tucked up against a connector (possibly USB, not the power lead?).
Even more helpful was the manual that simply said 'after connecting up as shown in the diagram, power on and follow the easy on screen instructions'. The set-up diagram had all the ports labelled BUT NOT the power button.
I have a Samsung laptop - about 2 years old.
About 6 months ago I noticed intermittant charging / output from the PSU block...so I investigated expecting it had failed.
I found the power lead (UK plug to cloverleaf socket) was very hot and plastic melted at the cloverleaf end. Not from the PSU block, or bad contact in the pins, and it was intermittant when I flexed the lead/strain relief.
I dissected it - bad assembly of the conductor to pin - all nicely molded up in solid plastic.
It would have probably have lasted as it spends most of its time static on the floor ... until I took it on a couple of trips and the wrapping and bunging in the bag precipitated the failure.
Hmm...Rosetta has solar arays to do what ?....absorb the light at the best wavelengths to turn it into electricity.
So how much is going to be reflected off? not a lot.
Then you have to steer them precisely, and the spreading 'spot' will be much larger than the lander's panels...which will be a the wrong angle most of the time.
And Fusion of course...
Its crazy that politicians are scrimping on the ITER project which will cost the world only about as much as a couple of olympic games...
(Or a crossrail phase 1. Then there will be a phase 2 and three at another 15 billion each)
(Were the London Olympics worth it? 14000 athletes at 9 billion pounds = c650,000 per athlete for a 2 week event !)
It is odd we can throw away cash like that for a bit of immediate sport gratification but cannot see further than 10 years ahead for the big important stuff.
It is sad to see - lots of people work really hard to make these things happen.
Spacex have had their near misses too - https://www.youtube.com/watch?v=nxSxgBKlYws
I was watching this live and thought...hmm, that 90 degree roll at launch dosn't look healthy.
This Antares launch looked slightly odd right from the start - to me it seems like the hot end drifts slightly to the left (towards the launch tower) at release, then corrects a couple of seconds later, but it is hard to tell as the camera is moving a bit too.
In my day at Uni, we learned concepts using PASCAL, then MODULA-2...which was good for me as I had done all my previous learning in BBC Basic. I just loved procedural programming and recursion.
Found this lovely mess of logic last month : http://interactivestructures.org/
Chap claims he is a programmer...and was employed as a lecturer at Yale !
Hmm...ITER will not be next year....(there is a schedule on the ITER website.)
ITER will run pulses for a lot longer than 10 seconds : http://www.iter.org/newsline/122/182
ITER has no fission reactor in it's plan. (power to site arrives over the French grid...so will have come from a fission plant somewhere, and from renewables. it is not intending to export any power. the site will not have any turbines or generators on it. (except as emergency site backup power).
I don't need to downvote...I just google for accurate information.
Not sure about lighting, but it seems to be a flipped image.
Anyway the millennium falcon scenes in star wars were probably faked : there is a chap who is trying to build a full size one but there is no way he can fit all the separate internal scenes from the 'star wars' documentary together inside the outer envelope.
THere are similar problems with 2001 ships.
I think (and tell people who can remember them) that 2014 3D printing is like 1982 dot matrix printing. Noisy, slow, bumpy, feint, fanfold fed (didnt fit A4 folders) monochrome etc.
I used it to print program listings. I tried to print graphics. I had an old moveable type press for crisper output. Other people used linotype? systems to produce blocks of text that were pasted up and rephotographed to make print plates. I had a pen plotter for linear stuff. Horses for courses.
But I too hate the media hype around 3D printing - and I do remember massive media hype around 'desktop publishing'.
Like the dot matrix printing dumped the pins...3D printing will probably dump the squirty plastic nozzle of curent designs in order to move on. But it is the software that is also driving this revolution. Slicing CAD models for printing is like the screen dump printer driver I wrote : part of the system that can make a useless lump of mechanism perform better, and the basic ideas of rasterising/slicing form the basis for newer mechanics to perform better.
...But I was sitting one evening and my backlight flickered. Hmm I thought, Is that related to the electrical magic smoke smell that is now drifting past...
Yes. The mains power lead was all hot and bothered at the clover connector. I mined into the plastic (having unplugged it) and the termination didn't look too good.
All is well - I went and dug out a replacement lead from my old laptop parts pile. OTOH, perhaps I should be worried - the old lappy was a HP...
Yes, except that the 555 is realy not a good choice for longer duration delays. Too much drift on the R or the C.
I designed some stuff years ago with a similar IC, but it had a built in counter so the timings could be pushed out reliably, but I cant remember the number - it had four digits and one of them may have been a 7.
Saved using a 4000 series counter bolted on.
But it is not quite that simple.
Trafic intersections controlled by lights operate in 'phases' where one or more light heads can be green. Eg a crossroads where there is not just one approach green at a time - usually the opposite approach is paired up. In many junctions there are all sorts of combinations of flow. Then there are pedestrian phases.
IF the hacker can find the level in the control system that makes their own aproach green and all others red, then that may be OK, but it would require more study of every junction;s setup.
PS, will people pleas stop flashing their lights (or horn) at roadwork temporary lights - in Europe, its will not work, and never has. (See my username - I design them).
Oh yes, reminded me too - way back when I upgraded my brothers PC motherboard...needed to make some veroboard adapters for the SIP > SIL sockets. One edge of the Vero strips sat in the SIL socket carefully crafted ends to fit the clips, soldered a row of DIP pcb sockets (cut in half to make SIL) to the other edge sort of surface mount for compactness....
Magnets to attach the power wires.
Yes they have been suggested and found to be too strong to just pull off but...don't just arrange for them to direct pull.
Magnets are strong close up, but the pull drops off rapidly so only small motion is needed. Thus arrange for the lead wires to run along a lever so that the force to pull the connections is minute.
Keep the wires and levers lightweight but stiff (carbon fiber etc.) so they don't contribute significant force on t6he magnets during jiggling.
---------------------------------------- rear face of rocket
Key: (=wire. _ = lever O=magnet pair with contacts between V=fulcrum fixed to rocket ....=space so the ascii art works.
At rest, there is a small gap between the lever and the fulcrum point. As the rocket starts to move, the feed wire tensions, loads the lever that can rock until the fulcrum makes contact and the magnet is popped apart and hangs free. The end of the lever could even strike a tag fixed to the flying truss instead of loading the wires.
As others have already said, you don't want to fire before balloon burst cos that would be silly. And not optimum mission.
Detecting burst is simple - tension on the support string will almost instantly drop to zero. Depending on rate of climb, G will decay to zero - she has mass and will continue to ascend after loss of baloon lift. This decay will be quite rapid too.
Potential problems : Swinging about could cause a false trigger - having seen a couple of other project videos with alarming swinging going on. This is where the barometric is used - to inhibit firing below a chosen altitude. THis will aid ground handling and launch.
Stability after burst is a big problem, but a pre-deployed drogue 'chute just below the balloon would help there. This would not cause significant drag on ascent and may also help dampen out swinging etc on ascent - the baloon is a large spring in itsself.
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