Team Eventorizon: Build Diary

[Revsmin]

Looking at it I think that's a double acting ram... is this the stuff from Hells Angel? And by the layout I'd say it's a flipper?

[Eventorizon]

Yes its meant to be a flipper, keep forgetting to say that.

Yes, the ram is double acting but I will only be using it as single acting. No, none of this is from Hells Angel, that's all in the garage.

[Revsmin]

If you're running it single acting with bungee return you don't need that monster 5/2 valve. All you need is a LP 2/2 with high flowrate.

[Eventorizon]

I figured. Got a link to something that will do the job?

I am also planning to widen the lower port for better flow in and then make a new insert for the base with a hole in it to act as the dump. Not very efficient but light weight.

[Liftoff]

With that type of ram ( both end caps are retained by circlips if I'm not mistaken) you could put a hole in the bottom endcap and fit a 1/2bsp QEV. Then you would not require high flow/large port solenoid valves to operate it. A small (1/8bsp) 5/2 valve will work fine.

[Eventorizon]

Yes, its has circlips top and bottom. So the 1/2bsp would go in the side and like I said before a small hole in the base?

I am going to try replacing the ram rod as I am certain that the one it comes with wont be able to take the forces. I will try Titanium as the same diameter and if that bends I will have to get it on the lathe and makes a 12mm or 16mm one.

[Liftoff]

No, I'd put a 1/2bsp at the base and put a QEV there. The other port I'd plug it off as you won't need it, if you use a QEV with a 5/2 valve then the 1/2 base port is all you need...it acts as a dump as well ( via the 5/2valve)
The top port you would need to enlarge to reduce back pressure.
(I had posted a couple of schematics on a thread somewhere)

What's the diameter of the rod? I'd guess is about 20mm steel - not going to bend that easy... on mine I replaced it with an aluminium one to save weight!

EDIT: Ermm, actually you do need the other port as a dump (sorry my mistake! )

[Mega Masher]

I have managed to get the Castle Link software working so I have uploaded Conker 3's data for you all to examine.

The different switch ons are as follows

1: Direction Test (Low voltage)
2: Interrupted spin up (No spin up)
3: Test Video
4: Tech-Check
5: Flow & Kaizer
6: Massacre and Drumroll
7: Galactus & Nightfury
8: 720

I have just uploaded the interesting ones (IMO): Current, Temperature and RPM at the output.

The key points though are...

Maximum Current: 254.7A
(The average given is useless because of all the stops and starts, unless it ignores those)

[ATTACH=CONFIG]4559[/ATTACH]

Maxiumum Speed: 11'096 RPM (Oh yeah!)
(It seems to happy sit up in the 10K range when its not hitting anything. You can see where the big hits happened where the RPM dives)

[ATTACH=CONFIG]4560[/ATTACH]

Maximum ESC Temp: 55.6 Degrees C
(Not overly interesting but just surprising considering that it was sat next to 3 straining batteries in a metal box!

[ATTACH=CONFIG]4561[/ATTACH]

Might seem stupid asking this, but why does the time on the graph go up to 700 seconds. Surely a fight would only last 180 seconds

New bot looks good btw

[Eventorizon]

Because that is the total length of time that it has been recording over since I got it and I have not reset it. None of the fights lasted anywhere near 180 seconds. Each thick vertical line indicates when the ESC was switched off.

[Mega Masher]

Oh ok then
Thanks

[overkill]

The current readings from the Castle ESC may not be accurate - I have been testing Mr Mangle's beater spin-up with a Castle ICE 160 HV ESC and monitoring it with an Eagletree data logger and a clamp ammeter. For some reason, the ESC is reporting much higher currents than the data logger or the ammeter, which broadly agree with each other.

[Mouldy]

How far out was the logger at peak currents nick?

[Eventorizon]

I thought 253A was far to high, it has a built in trip at 220A. Any chance of working out if its a ratio or scale?

[overkill]

Without digging out the data file, the Castle ESC was at least 50A higher than the other instruments. The meter and the Eagletree use dedicated hall effect current sensors that the ESC does not - I'm guessing the ESC measures the voltage drop across the FETs and doesn't get it right at the extremes. The ESC and the Eagletree logged the voltage almost identically.

[Eventorizon]

Need a reality check here. I am trying to calculate the bite I should set on Conker 3's new weapon and this is what I have.

Motor KV rating: 1083rpm, Max Voltage: 4.2v*4 = 16.8v, Speed: ~18'200 rpm, with 16:1 gearbox, Shaft speed 1137.5rpm, Wheel Dia: 73mm = ~4.34m/s

Weapon Speed: 11'000 rpm. (Taken from the data-logging on the original weapon)

4.34m/s > 260.4m/min > 260400mm/min / 11'000 = 23.67mm for 1 revolution.

If all that is right then the maximum bite of the weapon should be ~23.5mm. After this bite can only be less as the voltage drops and the maximum speed of the machine decreases.

Can anyone see a problem with that?