Flatpack

**harry hills** · 16th September 2015, 19:37

Decided to build something a bit more passive. No large KE weapon I'm afraid.

Flatpack is a 4wd 4 bar lifter which will be competing in the MMM competition in Germany.

Drive: 2x saturn-16 gearboxes with 775 motors
Weapon motor: 4240 sk3 brushless outrunner with a saturn-16 gearbox as the first stage of gearing.
Escs: 2x Tz85a botbitz 1x trackstar 150a
Batteries: 2x 2.25ah 5s Nanotech
Wheels: 2.5"x1.25" colsons with custom hubs
Frame: 5mm 304 stainless steel
Armour: 2mm and 5mm 304 stainless steel

first bit of design work. Rouging the layout to see what can fit where.

more in depth model work happening

Pretty much done here. It's not even close to being a full detailed model but I'll probably end up working arse backwards and redoing the CAD to be super detailed once the robot is complete.

Parts began to show up. I'll give you three guesses as to what this was and the first couple don't count.

Here you can see a motor mated to a wheel and a 3d printed timing pulley. I love having a printer. It gets way more use than I thought it would.

the weapon motor and how it mounts onto a the gearbox.

**harry hills** · 16th September 2015, 19:37

And here are all the parts for the weapon transmission. The lifter has 4 stages of gearing, 2 planetary by way of the saturn-16 then a spur gear stage and finally a timing belt and pulley stage.

A 12mm bore through the pinion gear for the second stage wouldn't have left enough meat in the gear so i made it a 10mm bore and stepped the shaft down. I had a whole new shaft CNC milled instead of modifying the stock one so I could have a spare for the drive. The pins are machined from the billet, not press fitted. I have no idea if this will make it weaker but it shouldn't really matter. It still runs dead smooth.

The pulley is machined into the lifter arm which is fairly neat. Props to Ellis for helping me draw the tooth profile.

The arm assembly with the bars.

Bare bones pretendo of the robots internals.

Pretendo of the steel frame.

my absolute favorite part is this bent steel wedge. I don't have the facilities to weld so I just went with a bent one for now. Needs grinding and sharpening but should be decent at keeping out some of the nasties.

lid is 2mm steel. Will have plastic or CF covers underneath the cutouts

**harry hills** · 16th September 2015, 19:38

Mounted the drive motors, machined the front driveshafts and bushings. Small amount of stiffness but it feels like it should wear in nicely.

Got all the holes tapped for the arm and countersunk all the plates for that.

beginning to look pimp and like a real robot.