Team Kaizen - Shu!

[Ocracoke]

A video of the final result, still with speed controller woes though :S

[Scottie]

Shu! look great bro! im looking forward to seeing it in real life. As to that twitching thing, it could possibly be a calibration issue. it might be that your remote is just on the edge of the minimum ppm that your sabretooth is expecting for a move stimulus, this will intern give the motor a really low pwm, to low to exceed stall under a load.

Somethings you can try: are you able to change the trims on your pot? Do you have another remote that you can link your bot to and try to recreate the same effect?

[Ocracoke]

I tried changing the trims and using the RC control from The Honey Badger which doesn't have this issue but the twitch persists. I've spoken to Garfie489 about this and he is OK with it so I guess I can live with it as is but that won't mean I won't try to get to the bottom of this.

With the time I've got left before the event, I think I'll be investing in making some alternate lifting arms to deal with the spinners (I have one idea in mind) and for the Nuts competition

[Scottie]

If it is ok to use then the pressure is off! id be interested to measure some signals on your sabretooth with an oscilloscope.

As for antispinners i hope you make something like when complete control went against ghost raptor. im sure it will be allowed

[Ocracoke]

As for antispinners i hope you make something like when complete control went against ghost raptor. im sure it will be allowed

Hahaha! I will err on the side of caution on that one.

I've fitted a set of longer forks on the front and I've got a even longer set from building Osu cut out but in reality, this is it before the event, bar some battery packing and a couple of supporting screws at the front. Otherwise, it'll be scuttling around the kitchen floor with me giving it various loads to try out lifting.

[Ocracoke]

I did a static test with The Honey Badger 1.0 shell, frame and battery to get to 1.6kg. Shu! was quite capable as it turned out, especially when you consider that the whole robot is running undervolted.

I've since also cut a new serrated lifting arm with a much shallower angle so hopefully that will work against spinners and reinforced the front plates (in the video, you can the front plates nearly coming off).

[MrCawdell]

Do you know whats making it tip itself over instead of transferring the power to the other bot?

[Ocracoke]

Do you know whats making it tip itself over instead of transferring the power to the other bot?

Its all about leverage. The pivot point of the arm, where the motor is, is about half way into the robot. The forks at the front are supposed to help lever onto the floor so more of the upward thrust goes into the lift of the opponent. However, the forks are 3mm thick and have a tendancy to bend.

If the pivot point was at the back of the robot as originally intended (there is a post from about November/December time showing where I originally wanted the motor to be, it would probably be better. Originally, the motor was far forwards but it meant the robor was forever turning itself over.

[Ocracoke]

The UWE Beetle Brawl was the first outing for Shu! and did OK. I don't have any videos of the fights Shu! was in but I know there were plenty of cameras about, I'll update the post later on with the videos.

UPDATE: Many thanks to Joe Brown for the in-arena camera footage. They are his videos linked below.

First fight against Crabsoluely Crawful went fine... right up until the point where the serrated arm broke in half. Upon closer inspection, where I had drilled the hole for the locking pin was too close to a serrated point and the arm simply tore itself apart under load. The worse bit of this was that the arm didn't want to play ball all the time afterwards so I stuck the control arm on Shu! and tried to leave it in the flat position.

Second fight against 7th Circle was the one I was dreading prior to the event as this was a vertical spinner. Although that fight bent a few of the screws to the wheels and cracked a front panel, it wasn't too bad. What was bad was that 7th Circle managed to put Shu! on its back and the arm jammed.

Video (24:43 and 26:47)
https://youtu.be/X_KFXuZN0xA?t=24m43s

So Shu! ended up in the Wooden Spoon melee and despite the arm not working properly, it managed to come 2nd in that fight with OMG the winner (a nippy robot I have to say).

Video (16:12)
https://youtu.be/gAAAE3UtgBw?t=16m11s

Then came the Gladiator fights and in the first one, Shu! again came second in the first fight with Catalyst the winner. The second one went badly as moments before the fight, the removable link for the drive fell into the robot. Shu! can move on just the one link but the speed of the robot reduces to ultra-so-motion. Modus Operandi then decided to take a corner out of Shu! and subsequently ended up in the pit.

Video (both fights)
https://www.youtube.com/watch?v=lGR1725HHlQ

Post mortem on the arm revealed that one of the gearbox gears had some of its teeth stripped, so a new gearbox (and motor) is needed but I am surprised that stripped at all given it was a all metal gear affair. Reviewing the footage, Shu! was definitely underpowered but the basic design works. I won't be working on Shu! now until ~July as I've got The Honey Badger and Kaizen to deal with but Shu! has definitely become a favourite of mine.

From left to right: The bent wheel hub screws, Modus Operandi's handywork on the control arm, the front forks having come loose, the damage in the corner and finally the stripped teeth on the lifting arm.

DSCF6097.JPGDSCF6099.JPGDSCF6101.JPGDSCF6102.JPGDSCF6105.JPG

It was great seeing a few of the roboteers and their robots who I've been talking with prior to this event, rather surprised to get one of Eric the Destructor's spinning discs as a thank you!

[Deathly Hallows]

Congratulations on Shu!'s performance at the event.

I reread the build thread to see how you controlled the limits on the arm. But failed to see how you did this. Do you use limit switches and a Arduino?

[Ocracoke]

I reread the build thread to see how you controlled the limits on the arm. But failed to see how you did this. Do you use limit switches and a Arduino?

I didn't, no. It is completely manual.

[Ocracoke]

Shu! has been on the back burner since the Beetle Brawl with all of the other projects going on but spent a bit of time putting it back together with a couple of minor improvements, those being:

• New DSMX receiver so I can use my OrangeTX transmitter
• M3 bolts added to the rear to prevent it beaching on its back

Other than that, pretty much everything else has been left alone. I'll need to redo the wiring in there at somepoint but it isn't essential right now. Looking forwards to a grudge match with Crabsolutely Clawful, soon hopefully.

[Ocracoke]

So Shu! is in the European Beetleweight championships, a scary thought. :P The robot does need a few new panels making for it (I have some spare polycarbonate laying around so will use that) but today, I built a new arm to replace the snapped arm from the UWE Beetle Brawl, again in polycarbonate. The lid is a test acrylic lid which I'll use as a template but I'll change the front panels as well at the same time.

DSCF6630.JPG

Other than that, the robot won't sport any other major changes until after the Beetleweight championships where, hopefully, it'll come back in one piece.

[scott]

Looking good, will see you at the championships!

[Albear]

Good to see shu! up and running again! Havnt ben on in a while but ive got plans over christmas to get building again