RC Technology
03-10-2007, 09:36 AM
#17
Originally Posted by Kyew
our rc cars' power to weight ratio is quite superior to most real size racing cars. hence theories on 1/1 scale car dynamics do not apply in some cases.
Not to mention that our rc cars spend very little time in steady-state cornering. Most in transient. Esp true in tight tracks where we are throwing the cars in and out of corners rather than feeding power slowly.
03-10-2007, 10:27 AM
#18
Originally Posted by Ray Lan
Agreed agreed. Not to mention that our rc cars spend very little time in steady-state cornering. Most in transient. Esp true in tight tracks where we are throwing the cars in and out of corners rather than feeding power slowly.
Not to mention that our rc cars spend very little time in steady-state cornering. Most in transient. Esp true in tight tracks where we are throwing the cars in and out of corners rather than feeding power slowly.Need to apply dynamics and control on RC meh.......hahaha
Anyway, when I'm free, I'll go scan some notes on Gear Ratio Optimization and post here. It's on how to make full use of the motor's max torque and overload capability.
Althought I myself would not go and calculate it......haha........just try gearing lower until motor burnt........hehehehe..........
Last edited by Nipple; 03-10-2007 at 10:54 AM.
03-10-2007, 10:51 AM
#19
Maybe Ah Lan would like to explain why a hollow steel shaft is better then a solid titanium shaft in terms of weight and strength.
That explain why some company release hollow steel drive shafts rather then titanium shafts as optional or standard parts.
That explain why some company release hollow steel drive shafts rather then titanium shafts as optional or standard parts.
03-11-2007, 10:10 AM
#20
hehe.. Interesting discussion. Well I'm kind of a tech freak, so although I may be lazy in applying the theories, I like to find out... curious me.
But its true that we have to keep our hobby FUN. I was once stuck in a meticulous mode, must setup everything perfect, I spent so much time doing it I didn't have fun at all. The "like that can oreadi la" attitude lets us enjoy more and keep us sane.
The transient and steady-state stuff is better left to the big boys at F1. we should use what we know and enjoy as much as possible.
Titanium = $$$ due to material cost and machining cost, harder to cut.
Steel = Cheap, hard to cut, but most tool steels are made for cutting steels.
A hollow tube is almost as strong as a solid tube in torsion and less so in bending. So its a matter of cost effectiveness. Full size racing cars almost never use solid tubes whether its chassis or suspension(arms,roll bars), drive shafts. Only the most highly stressed parts like crank shafts, cam shafts(hollows do exist, but $$$$$$) valve stems use solid pieces.
But its true that we have to keep our hobby FUN. I was once stuck in a meticulous mode, must setup everything perfect, I spent so much time doing it I didn't have fun at all. The "like that can oreadi la" attitude lets us enjoy more and keep us sane.
The transient and steady-state stuff is better left to the big boys at F1. we should use what we know and enjoy as much as possible.
Titanium = $$$ due to material cost and machining cost, harder to cut.
Steel = Cheap, hard to cut, but most tool steels are made for cutting steels.
A hollow tube is almost as strong as a solid tube in torsion and less so in bending. So its a matter of cost effectiveness. Full size racing cars almost never use solid tubes whether its chassis or suspension(arms,roll bars), drive shafts. Only the most highly stressed parts like crank shafts, cam shafts(hollows do exist, but $$$$$$) valve stems use solid pieces.
03-11-2007, 10:39 AM
#21
Looks like most pple that posted here are EP Players.
Anybody like to discuss on Capacitors and diodes?
I think most pple know the general effect of them, but what's the theory, calculations? The bigger the better? Why different capacitors have different effect on different brand of batts?
And also on Seo Tune "Magic Band"
TN Racing "Black Beans"
Battery Charging Mats
Etc Etc....
Anybody like to discuss on Capacitors and diodes?
I think most pple know the general effect of them, but what's the theory, calculations? The bigger the better? Why different capacitors have different effect on different brand of batts?
And also on Seo Tune "Magic Band"
TN Racing "Black Beans"
Battery Charging Mats
Etc Etc....
03-12-2007, 08:17 AM
#25
Originally Posted by SuPerDraGon
Black beans? take how long to cook and eat?
Anyone need some accelerometers to mount on the RC cars to measure vibrations and dynamics? I can lend some...
Anyone need some accelerometers to mount on the RC cars to measure vibrations and dynamics? I can lend some...
My Formula SAE electronics team tried to do up such a thing but had no time/effort/money. Maybe I can adopt this setup for my guys.
What kind of setup are we talking about?
Cost?
03-12-2007, 08:24 AM
#26
Actually, my personal interest is ball bearings, bearing/bushing oil and grease.
For EP Touring, I like NMB ones. Stainless Steel, Metal Shield, Sound checked. Squat Preision call them VC (Vibration Control), a higher grade is RD (Racing Dry). (For GP, anything that can turn can liao lah.......haha)
I will soak the bearings in a special solution for 1 week to degrease. Then soak in turpentine, then use RPM bearing blaster and contact cleaner to clean, then use hair dryer to dry them. Next soak in Microlon for 1 month.
I only use squat LO-1 Bearing oil nowadays. It's cheap, not too light until bearings will slip under hard acceleration, not too heavy and will give very smooth spin. Can last for 2-3 runs. Do not react with dirt and other particles.
Please remember. good bearings spin smoothly. But if you think bearing that can spin very long is good, think again. I give you a used clutch bell bearing, it can also spin very long......haha.....but it slip like hell.
Squat got other 2 types of bearing oil, 1 have I guess contain telfon powder (like Kawada's natalie) and the other claims to be bearing oil with world's smallest particles (Can't remember how many nano). I have tried that 2, but still prefer the LO-1.
Many pple may use F-Zero, but it's not cheap and have to be sprayed before every run to make full use of it. Cos it's very light and dry up fast.
For bushing, I have also tried a few bushing oil, the only one that impresses me is Power's Gigalube. Did some testing and it produced some impressive results. Also it's not expensive.
For grease, metal to metal, I use kawada Jodie, plastic to plastic or plastic to metal, I use hybrid's.
Many lubrication such as gigalube, kawada natalie, jodie etc claim to have osmosis effect or thin film coating. Other claim to be nano technology......
Nano carbon marketed by yokomo is quite interesting too.
And Seo Tune "magic band" somehow affect the electrons flowing in the wire and result in less motor arcing.
For EP Touring, I like NMB ones. Stainless Steel, Metal Shield, Sound checked. Squat Preision call them VC (Vibration Control), a higher grade is RD (Racing Dry). (For GP, anything that can turn can liao lah.......haha)
I will soak the bearings in a special solution for 1 week to degrease. Then soak in turpentine, then use RPM bearing blaster and contact cleaner to clean, then use hair dryer to dry them. Next soak in Microlon for 1 month.
I only use squat LO-1 Bearing oil nowadays. It's cheap, not too light until bearings will slip under hard acceleration, not too heavy and will give very smooth spin. Can last for 2-3 runs. Do not react with dirt and other particles.
Please remember. good bearings spin smoothly. But if you think bearing that can spin very long is good, think again. I give you a used clutch bell bearing, it can also spin very long......haha.....but it slip like hell.
Squat got other 2 types of bearing oil, 1 have I guess contain telfon powder (like Kawada's natalie) and the other claims to be bearing oil with world's smallest particles (Can't remember how many nano). I have tried that 2, but still prefer the LO-1.
Many pple may use F-Zero, but it's not cheap and have to be sprayed before every run to make full use of it. Cos it's very light and dry up fast.
For bushing, I have also tried a few bushing oil, the only one that impresses me is Power's Gigalube. Did some testing and it produced some impressive results. Also it's not expensive.
For grease, metal to metal, I use kawada Jodie, plastic to plastic or plastic to metal, I use hybrid's.
Many lubrication such as gigalube, kawada natalie, jodie etc claim to have osmosis effect or thin film coating. Other claim to be nano technology......
Nano carbon marketed by yokomo is quite interesting too.
And Seo Tune "magic band" somehow affect the electrons flowing in the wire and result in less motor arcing.
Last edited by Nipple; 03-12-2007 at 09:05 AM.
03-12-2007, 08:33 AM
#27
Originally Posted by Ray Lan
Hey thats really cool! The car that pulls more lateral G's have more grip and therefore will be a better contender for fast laps.
My Formula SAE electronics team tried to do up such a thing but had no time/effort/money. Maybe I can adopt this setup for my guys.
What kind of setup are we talking about?
Cost?
My Formula SAE electronics team tried to do up such a thing but had no time/effort/money. Maybe I can adopt this setup for my guys.
What kind of setup are we talking about?
Cost?
You can also connect some strain guages to measure your car's flex....hheehe
...Your guys just want to collect data using data loggers or DAS transmitting real time via bluetooth/wifi to a pc or a on board dynamic control system??
I think for RC, Eagle Tree is a example of a datalogger. It collect data of your run. Then you can analysis the data offline. In fact Robtronic I-Cube has rather similar function also.
Too bad NTU don't want to compete with NUS thus they made a Solar (PV) Powered Car instead to compete in Australia this year.....
One question Ah Lan, do you guys do 3D Finite Element Analysis of your components?
Last edited by Nipple; 03-12-2007 at 09:08 AM.
03-12-2007, 09:35 AM
#28
Ya, wanted to do datalogging. We managed to log the throttle position, engine rpm and a few other stuff. I wanted to measure Gs pulled cos I do suspension, wanted to see what works and wat doesn't. The Elect guys don't want to buy off-the-shelf cos they wont score in FYP... but hey you have to start somewhere. must be humble admit defeat and learn form pros ma... oh well... those were frustrating times...
At the end of the day I borrowed Ah Ben's Pro LCS and strapped it to the car to time our laps.
Some competition will be great... We always hopped to have NTU build a car to run against us. friendly competition will always lead to improvement in every way. Oh well.. maybe someday.
We do FEA, but use COSMOS works cos our school run SolidWorks. Self learnt, so we do design with some buffer in mind.
At the end of the day I borrowed Ah Ben's Pro LCS and strapped it to the car to time our laps.
Some competition will be great... We always hopped to have NTU build a car to run against us. friendly competition will always lead to improvement in every way. Oh well.. maybe someday.
We do FEA, but use COSMOS works cos our school run SolidWorks. Self learnt, so we do design with some buffer in mind.
03-12-2007, 12:01 PM
#30
Back to RC, now a bit on GP.
Not something new, Supercharger and NOS for RC,
Source: http://www.rbinnovations.com
Anyone applied Fluid Dynamics to calculate and optimize fuel line inner diameter, how it should be coiled, height, length, pressure.....etc etc
Not something new, Supercharger and NOS for RC,
Source: http://www.rbinnovations.com
Anyone applied Fluid Dynamics to calculate and optimize fuel line inner diameter, how it should be coiled, height, length, pressure.....etc etc
