Guest
1651
VB and the development of wizards / Re: P, Q, R parameter
« on: May 03, 2010, 12:12:04 PM »
Seconded. Thanks Russ.
Cheers
Ian
Cheers
Ian
Hello Guest it is April 26, 2024, 06:22:46 AM
Show Posts
This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.
HIYA Stirling, question ,there is a fellow doing probing of an engine intake ports. Can your crawler routine probe the inside of a 3d object such as a port?
HIYA Stirling, question ,there is a fellow doing probing of an engine intake ports. Can your crawler routine probe the inside of a 3d object such as a port?Hi - It's basically a bed o' nails with the added benefit of only probing inside a prescribed boundary. As you know a standard or dumb bed o nails only probes inside a defined rectangle which can mean it spends an inordinate amount of time probing useless space. All I can sugest is your fellow gives it a whirl. Don't know if you've seen it but there's an Italian company in this thread www.machsupport.com/forum/index.php/topic,4352.msg97649.html#msg97649 that has a couple of nice vids on their site and youtube of the routines in action.
Let me know how you get on.
Cheers
Ian
HUM there is really nothing to probe in the Z axis just a big hole. The area to probe would be in the X/Y directions and step down in z as it goes deeper into the port.
Your crawler routine works great but I don't think it will work in this application unless it could be modified to crawl the perimeter from the inside out then step down.
(;-) There IS a market for a PORT probing routine to do this IF you are interested.
I have seen your routine do the combustion chambers of the head, that IS a perimeter and bed of nails type of probing solution
Thansk
HIYA Stirling, question ,there is a fellow doing probing of an engine intake ports. Can your crawler routine probe the inside of a 3d object such as a port?Hi - It's basically a bed o' nails with the added benefit of only probing inside a prescribed boundary. As you know a standard or dumb bed o nails only probes inside a defined rectangle which can mean it spends an inordinate amount of time probing useless space. All I can sugest is your fellow gives it a whirl. Don't know if you've seen it but there's an Italian company in this thread www.machsupport.com/forum/index.php/topic,4352.msg97649.html#msg97649 that has a couple of nice vids on their site and youtube of the routines in action.
Is that also why we can't nest macro calls?What happens?
Ah, but there is so much more to it, Ian...LOL - hang on a cotton pickin' minute! I offered my answer to the question that was asked. I'm well aware there are all sorts of complexities with interpolated motion but that wasn't the question here.
It is actually outside the realm of the original question, but...Too right...
...multi-axis moves is where it gets interesting. On linear moves, do you scale each axis independently, or deal with the dominant axis and have tests for the dependant axes on when to take a step?The latter
And how do you deal with circular moves?The same way, but with the added complexity that the dominant axis changes (depending on the length of the arc) as the path progresses.
On the last system I was involved with, acceleration was handled with a lookup table. Modern stepper motors all have a "knee" in their torque/velocity curves, and with an acceleration lookup table you can take advantage of the increased torque at lower speeds without overtaxing the motors above the knee. It is those aspects in which I'm interested (I'm a mechanical engineer but very interested in all aspects of motion control so I know intelligently how to maximize system performance). My familiarity with DIY CNC led to the adoption of the Allegro 3977 driver chip for several products at my last employer in preference to less integrated solutions...
