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lnxfergy
12-20-2009, 01:00 PM
I finally started assembling Issy2 yesterday. It's not 3 weeks to RoboGames, but I figured I'd get a bit of a head start this time around (Robogames is just about 4 months away, so I have like 5X as much time to build Issy2 as I had to build Issy!). The body is now assembled, I'll be adding mech gear over the coming weeks.

Issy2 isn't all that different from IssyDunnYet, most of the changes are in software. Changes for this year include:


Bigger body, IssyDunnYet was just too small to fit those target plates on easily, it limited his range of motion. The body this year is about 6" long and 5" wide.
Back to 3DOF legs. Changes in software make this possible. Issy2 has a full IK solution, and is doing interpolation in the ArbotiX, thus the servos get full power (Last year, I was effectively running my servos at 1/3-1/2 power due to a mis-understanding of the internal AX-12 software).
With IK, and the gait engine, I'm hoping to double Issy's burst and turning speeds over last year.
Better software for the Trendnet camera is a priority. I was using a very poor frame grabber last year, which caused some interesting side effects.
Better fine grained control. This is probably the most important part, especially for targeting.
If time allows, implement fly-by-wire. I envision a number of Sharp IR sensors helping Issy2 avoid obstacles.

I'm not entirely sure what his firepower and upper body will look like. I've got a hacked defender sitting on the desk, but I may end up using 2 tank guns instead.

Here's a video of Issy2 walking around, no mech gear yet though:

http://www.youtube.com/watch?v=enpNE0SS2uA


-Fergs

Zenta
12-20-2009, 02:22 PM
Hi,

Great work on the different gait and kinematics!
The body rotation seemed a little bit rough though, but overall very impressive!
What sort of remote controller are you using? A joystick connected to a PC?

Looking forward to see some mounted gear.

-Zenta

lnxfergy
12-20-2009, 05:38 PM
Here's the CAD models I'm working off of for this build. The black squares around the bottom edges are the target panels. The target transponder would be mounted behind the front panel. A single defender gun, camera, and arbotiX are located on the tilt servo for the head.
http://forums.trossenrobotics.com/gallery/files/1/7/6/8/issy2-defender_578121.jpg

-Fergs

lildreamer
12-20-2009, 07:22 PM
To think Rodney Brooks from MIT was doing this kind of work 15 years and it was considered cutting edge
most of his insects were built around the FSM engine ( Finite Sate Model)
his belief was intricate designs of behaviour can occur if you have several layers of simple finite state rules layered over each other....
and now we are using such designs for play things....amazing

excellent work - love the design:cool:

Noog
12-21-2009, 02:39 PM
Nice work Fergs! I love to see how a good robot evolves into the next iteration.

Do you have an estimated final weight for Issy2?

Noog

lnxfergy
12-21-2009, 03:01 PM
Do you have an estimated final weight for Issy2?

Legs + center chassis plates = 1090g
Battery = 158g
Tilt Servo + brackets = 81g
Defender Gun = 267g
Trendnet = 87g
ArbotiX = 49g
Scoring system (4 plates + MINI) = ~100g

I figure about 1832g, I figure another 150-200g or so for wiring, lexan, and turret framing. So, somewhere in the 2kg, 4.5lb range? It's heavier than the final 2DOF IssyDunnYet, but I'll also be running the servos at full power, and my IK+gait developments will reduce wear and tear.

As you may notice from that parts list, I'm planning to go with a defender for now. I'll be making some brackets this afternoon, hopefully I'll have some pics of the progress tonight.

-Fergs

Noog
12-21-2009, 08:38 PM
Defender Gun = 267g

As you may notice from that parts list, I'm planning to go with a defender for now. I'll be making some brackets this afternoon, hopefully I'll have some pics of the progress tonight.


Personally, I prefer the look of the defender. It seems a little more menacing to me. =)

Did you include ammo in the weight calculation above or was that just for the defender hardware?

Noog

lnxfergy
12-21-2009, 08:39 PM
Personally, I prefer the look of the defender. It seems a little more menacing to me. =)

Did you include ammo in the weight calculation above or was that just for the defender hardware?

Noog

Yeah, after I took the body/turret design from the tank gun design, plopped a defender on it, I liked it. Looks sorta like something from Skynet....

That weight is after I've cut a bunch of plastic off the gun, and with the hopper is about 60% full.

-Fergs

lnxfergy
12-22-2009, 09:31 AM
I got the gun, camera, and arbotiX mounted last night. He walks pretty well still. I'll probably be dis-assembling him later today/tomorrow to paint the gun, make the lexan cover for the turret guts, and die the Bioloid brackets. Then during re-assembly I can put in the final wiring, and he'll be mechanically done (except for targeting plates and transponder).

-Fergs

http://forums.trossenrobotics.com/gallery/files/1/7/6/8/issy2_543163.jpg

jes1510
12-22-2009, 01:09 PM
Dang it Fergs, this is simply not fair. We need something to give us and edge over your awesome machines.

mannyr7
12-22-2009, 03:18 PM
Dang it Fergs, this is simply not fair. We need something to give us and edge over your awesome machines.

I suggest a third category of competition... competent roboticists :p (of which I am am not one)

Noog
12-22-2009, 09:20 PM
I'll probably be dis-assembling him later today/tomorrow to paint the gun...

Have you thought about painting the brackets? I realize that the cosmetics of Issy2 may not be your highest priority, but a cool paint job never hurt. =)

lnxfergy
12-22-2009, 09:37 PM
Have you thought about painting the brackets? I realize that the cosmetics of Issy2 may not be your highest priority, but a cool paint job never hurt. =)

I'm actually going to dye the bioloid brackets (some black, some orange, pretty much like the CAD model). Take a look at my other bot SMALdog, he's got red-dyed brackets. The metal brackets will be mostly hidden away inside.

-Fergs

lnxfergy
12-23-2009, 02:38 PM
So, Issy's brackets got dyed this morning, I'll be making the new tilt chassis later today:
http://forums.trossenrobotics.com/gallery/files/1/7/6/8/issycolor.jpg

nagmier
12-23-2009, 04:28 PM
Nice looking mech fergs!

Adam
12-23-2009, 07:56 PM
The orange looks cooler than I would have thought.

rebel
12-23-2009, 10:13 PM
Orange looks good :p

lnxfergy
12-27-2009, 12:06 PM
Painted the gun, got the lexan covers ready. I may still redo the inner turret bracket once more to shorten up the cab about an inch (it's about an inch longer than I would like, I forgot to account for wires on the arbotiX in the CAD model).

I'm going to have to find something different to drive the guns, the motor driver on the ArbotiX just can't source that much current, it drives the tank guns alright, but not this big beast of a gun. Final wiring is also in place. It's mostly now just software work and mounting target plates eventually (and tuning the turret size if I decide to).

-Fergs

http://forums.trossenrobotics.com/gallery/files/1/7/6/8/issy2_604101.jpg

darkback2
12-27-2009, 12:13 PM
Hey Fergs...I swear by the battle switch. (http://www.trossenrobotics.com/store/p/5467-BattleSwitch-radio-controlled-10A-relay.aspx)..though there are probably cheaper things out there.

DB

lnxfergy
12-27-2009, 12:38 PM
Hey Fergs...I swear by the battle switch. (http://www.trossenrobotics.com/store/p/5467-BattleSwitch-radio-controlled-10A-relay.aspx)..though there are probably cheaper things out there.

DB

Yeah, I've got a pile of 42V,14A SSRs in an SOT-23 package sitting here... just gotta find a breakout board for them. I swear I had a dozen of those Sparkfun breakouts for that package, but can't seem to find them.

-Fergs

rebel
12-27-2009, 12:41 PM
Looking good. :p