ASA direct drive mount - rumours.

[harry page]

Hi

I do not have a ASA drive and cannot comment on its performance , but I do not think its unreasonable for it to do what its supposed to do !

I fully support new ideas , and most people will accept teething problems as long as they are rectified

But as I said earlier I would not buy anything else off them as my dealings with them so far have not been good !

It took them three weeks to admit they had got my money and still waiting for my corrector

Harry

[ollypenrice]

Thanks for the support.

I think we are talked out on the ASA situation in the absence of further evidence. I would, though, like to know more about how you make an electric motor that turns at the speed of a watch's hour hand. The electric motors that I know would only work on a mount being used by an observer living on a pulsar!

I'm sure it must be the future and if it is really software dependent then it might not be too expensive in the end. A digital watch costs less to make than an analogue.

Olly

[MartinB]

These direct drive mounts are pretty exciting and I hope the technology becomes robust. Even if I had the money to blow I would still prefer to let others do the pioneering!

Thanks for the info Olly.

[johninderby]

By the time the direct drive mounts are perfected maybe I'll be able to afford one

How long before we see something like a Celestron CGE PRO Direct Drive mount?

John

[Ogri]

"but I do not think its unreasonable for it to do what its supposed to do !"

Well that depends. As always, there can be unintended consequences (e.g. what about possibly unavoidable and excessive localised bearing wear?). Any links to info on the system they use available, out of interest?

"I fully support new ideas"

Within reason, so do I. It wouldn't be reasonable to have a £5 billion nuclear powered can opener, for example. Plus solutions looking for problems tend not to end up turning out well.

Just because you CAN do something (or THINK you can do something), doesn't mean you necessarily SHOULD do something.

There's a lot of fortunes been lost through lacking that sort of common sense, and there always will be.

I know someone that did precisely that, with a very well designed, very well engineered, but totally impractical, pointless, and 'marketless' toothpaste dispenser.

A very nice, very intelligent guy that should have stopped what he was doing well before he got to a £500 investment of his money in it. But it ended up burning a few extra zeros on the end of that, sadly.

[Marmite]

I would, though, like to know more about how you make an electric motor that turns at the speed of a watch's hour hand.

Olly

Ask the people at Astelco. They successfully make and sell direct drive mounts commercially. Go ask PlaneWave's engineers. They have built a direct drive mount which they're offering for sale. Go ask the people who design and construct mounts for professional observatories. They use direct drive exclusively.

The advantages of direct drive are simply too great for that system to remain unavailable to the general amateur astronomical market. Things change. Those who initially resisted CCD imaging were eventually forced to embrace it or give up. Those who attempt to resist any overwhelmingly superior new technology eventually get converted or shoved aside.

You don't understand or like the direct drive concept but seem to think that means it's unworkable, even though direct drive has been the preferred mount system of professionals for decades. Now mass-market technology has finally caught up with the pros, which means that sooner or later - like it or not - the current stable of mount manufacturers will either have to switch to direct drive if they wish to survive as major players, or limp along offering "old school" mounts to a dying breed of old fogies who refuse to accept change, even when it's for the better.

That's the way the world works.

[Merlin66]

When I worked for Rockwell in Automotive, they developed and patented a small pizo electric motor: almost infinitely small step size and a torque which would lift an elephant.

The principle is very simiple.... you know the "clicker" you use to give a spark to light the gas.... well what is happening there is you are squeezing a crystal and it gives off electricity... reverse the process... put a pulse of electricity into the crystal and it will "shrink" ...now imagine a stack of these crystals where the edges can index a shaft....

I was going to use this fantastic technology for electric window operations.... Rockwell were "made an offer they couldn't refuse" by Hitachi to buy the patent so they could use it in small motor applications... Haven't hear anymore about it. It would have made a great direct drive solution to our astronomical drive problem.

Ken

[steve51450]

I like new technology and although it can have teething problems these are sorted within the 1st few consumer glitches. To this effect, I took a risk in September and sold my much loved ap1200, even though it was by far and away the best mount i have ever owned, it is still based on old technology, albeit very robust well machined old technology

I have replaced my ap with a chronos hd 32 which should arrive sometime in march and i am quite looking forward to being a guinea pig for new technology , although i must admit its a big leap going from a proven Thoroughbred to the new fastest colt on the block.

Out of interest what is the difference between direct drives & harmonic drives ?

[Merlin66]

A direct drive is just that.. no intermediate gearboxes just straight onto the output shaft.

The harmonic drives are a bit like a small disk being rotated internally against a slightly larger ring; as the disk rotates it tends to roll the ring at a slower speed. ( This principle is also used in mirror grinding machines to slowly "index" the mirror under the polisher)

By accurately setting the "gap" between the disk/ ring and a good choice of input speed a harmonic gearbox works very well - and much cheaper and easier to produce than an epicyclic gearbox which is similar but has multiple gears and supports.

Ken

[steve51450]

ken

thanks for that, it helped

[ncjunk]

Interesting topic even if some replies are edging towards contfrontational...normal for some threads though.

The concept looks good and i like the idea of a system that regulates

its tracking rate using encoders"100 times a sec to achieve .03 (?) arcsecs"

for me the price has to drop and i want to see it working as, like olly says,

software is sometimes unreliable to begin with.

In response to mentioning Microsoft as a bad example there aré also good

examples of hardware software combos like plc systems in the automation industry. The software and hardware in these is simple and reliable so not all software is bad....just who programmed it.

[NickH]

Oh there is no doubt the future is in direct drive, non at all...but I think the issue was the tech support and teething problems with this specific model and how they were being addressed, and the nature of the way that the thread was taking its course. If Marmite is a dealer, or is in some way connected with the product, it would be far better to say so.

[RobH]

I agree, technology moves on and direct drives are highly likely to be the future and when thay are proven to work at an amateur level and can work as effectively and reliably as my AP1200 I will happily buy one.

Marmite. Olly never said he was against direct drives at all. He was simply saying that there was a problem with an ASA that he knew about, and for anyone considering buying one to be careful.

He has always been a polite and helpful memeber of this forum and does not deserve the tone you have been taking to him in your replies.

As a professional sound engineer of 30 years experience at a high level, I have seen the demise of analogue mixing consoles and now exclusively use digital ones.

When they first came out however, I wouldn't use them as they had a track record of unreliability and in my opinion were still in a testing stage.

This wasn't because I had anything against the technology as such, it was simply because they weren't ready yet.

When they were, I switched over.

I have no personal experience of DD mounts, but the same principle applies....make sure your product works properly before marketing it.

This benifits both the manufacturer in terms of reputation, and the customer who wants a reliable working product.

Rob

[NickH]

Oy....you're talking about my research & dev work Rob...:-) (Promix/01V/02R etc etc)...

lol

[ncjunk]

I have similar issues with PC based PLC systems..in principle a great idea but the early ones were a card mounted on a spare slot of an industrial PC. Great idea to put a system which requires stability on an unstable base.

They are a lot better now as there are a few out there specifically designed for the job rather than piggybacked onto a .....insert rant here...PC.

I think the prices of the direct drives will eventually fall as to me there doesn´t seem to be anything complicated in the theory and I am sure a trade off could be reached between quality and price to provide a mount which improves on the currently available EQ6 but for a similar price (trade off being that perhaps we could settle for a higher PE which is still better than the EQ6)

I am thinking lower end of the market as I would rather buy a new motorbike than a direct drive mount for 13,000 euros (sorry guys!)

[Merlin66]

IMHO we need to consider what is driving the market. Let's be honest and say compared with automotive or games consoles etc we, the amateur astronomers, don't exactly represent a hot growing market.... To get new technology into our field either we pay the upfront R&D costs and live with the limited production volumes which will always result in higher unit costs or we "piggyback" on some mature technologies which can be easily and cheaply adapted to our area of need.

Over my 40 years in manufacturing I've seen some great, I mean like really great ideas prototyped, but never saw the light of day in full production....tooling, testing, jigs and fixtures, target market volume...all work against you.

Ken

[RobH]

Oy....you're talking about my research & dev work Rob...:-) (Promix/01V/02R etc etc)...

lol

Sorry Nick ....you know the scenario....when a digital console crashes mid-show it's 'end of story'....and who gets the finger of blame pointed at them....the bloke who ordered it ....the finger of blame is usually followed by the P45

Happily, although I've had a couple of minor issues since changing, they haven't been show stoppers.

Were you also involved in the PM1D/5D?

Cheers

Rob

[NickH]

The guy sat next door to me was/is...

and my old boss is..

PM1D...you weren't at that Clapton gig were you?

[RobH]

No, I wasn't at the Clapton gig, but I did hear about it of course!

I'm a Soundcraft VI6 fan myself, although I will happily take a 5D as you can find them pretty well anywhere and thay are bombproof, although right fiddly to use on the fly

Cheers

Rob

[MartinB]

Ultimately there is potential for direct drives to become much cheaper than current high end geared mounts so lets hope any problems continue to be ironed out.

[NickH]

Amen to that!

[George]

What I don't get is the mount has software issues and some mounts work and others don't how can that be? Software either works or it doesn't, the only thing that could throw the software is if different components were used from mount to mount, then obviously the software would have to accommodate different hardware.

Maybe the pre-production models were overly expensive and the production models had cheaper electrical.....something doesn't add up.

[barkis]

I don't understand the difficulty. All that is needed is to directly drive the polar shaft at the sidereal speed of .000696rpm.

How hard can that be.

Ron.

[George]

I don't understand the difficulty. All that is needed is to directly drive the polar shaft at the sidereal speed of .000696rpm.

How hard can that be.

Ron.

Is that metric or imperial I remeber NASA crashing a probe into Mars because they got the two mixed up

[NickH]

Astrosysteme Austria

That's not far short of being affordable for most serious imagers using high quality refractor setups