Team Death - New Heavyweight

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Yeah. That is definitely an issue we had on sunday. It was slipping on the surface we used, although we weren't able to fully decide if it was due to the wet and slippery surface, or an issue a little bit more sinister at the time. But in hindsight, Jamie is probably correct.

Weight wise, we are already probably within 5-15kg of the limit, so we can't do too much extra, unless we take stuff off. I wonder if we could weld a slab of something between the wheels, to weigh them down a little and give them extra traction.

If I recall correctly, the current wheels are wheel barrow wheels, the type that don't have air in them.

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Another week into 2018, another weekend of building!

Before today however, Colin had spent some time with an angle grinder, retreading the tyres. They almost look like they could have always had that tread!

We started today by weighing everything, as for the past few Sundays both myself & Colin have starting voicing concerns over the overall weight of everything, so we brought out the scales, piled everything onto it, and we are up to within 5kg of the weight limit at this point.

Next, we discussed our options for the concerns raised during the motor testing last weekend, which were somewhat disappointing. Two options were discussed, we can either get some extra sprockets in the mix, and increase the ratio from 4:1 to 8:1. There is a potential issue here though, as there isn't enough space at both sides needed for this, the right hand side would fit correctly, but the left would go over to where the jaw control sprocket, chain/belt and motor is. Whilst there is space in other places to do the same but in a different place, so it might end up a bit of a jigsaw puzzle inside. Another option, is using friction drive. There is just enough room on both side to do this, without having to jiggle things about or place things in mismatched locations at each side, we reckon. Later this week, Colin is expecting a large box of sprockets, bushes and other similar items. So next Sunday we'll take a look in there and see if there is anything in there to sway our decision.

A large portion of the day was also spent drilling out holes in the scoop and jaws, after realising we may need to add extra weight as part of the drive changes, even if we don't end up going that way, the less weight will perhaps afford us more armour in areas where needed. The holes have been drilled strategically, in places where it won't cause weaknesses, such as in the jaws themselves, which will usually be within the scoop anyway.

We ended the day by testing out the motors, but removing the ESC from the equation. The roughly 50% charge LiPos were quick to spin up the wheels, although they still skidded on their new treads. The first thing we'll do next week is probably repeat the test with the ESC, and slowly increase the speed to see if we get any better control, and if with a controlled acceleration the new treads will prevent major slips. What we find in Colins box of stuff and how that test goes will take us in the future direction for the bots drive.

Some images from today;
1) The new tread on the tyres
2 & 3) The cut holes in the jaws
4) The holes on the outside of the jaw
IMG_20180204_123549.jpgIMG_20180204_143001.jpgIMG_20180204_145206.jpgIMG_20180204_123435.jpg

[team death]

BRRRRR-it's been a raw day with a freezing wind but the build continues.
First task was to test the drive system via the speed controller to see
if the wheel spin problem is better with a gradual power increase,
So we set too wiring up the motors and the speed controller and the
radio control-this seemed to take quite a while, I think mainly because
the wiring circuit is not so much plug and play its more screw,zip ties
and gaffa tape-but we are working on the correct wires and connections
for this and the final version should take 5 or 10 minytes tops to
connect.
Anyroad we tried the Robot with the RC gear and although it managed
to bust the door again the performance was sluggish and some wheel spin
still occured so reluctantly we need to modify the gear ratio.
After removing the speed controller we began work on a idler sprocket with
a 2 to 1 ratio, this was in the form of a stub axle type shaft supporting
a couple of sprockets on a brass bush-fabrication went really well until
I realised that the axle shaft had been made too short and didn't allow
for the second smaller sprocket-this was a real set back but after I had
taken Adam to the bus stop I was able to rectify the mistake and I'm
just awaiting sprocket size confirmation to finish the lathe work.

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Furthermore to Colins post, I have a few images, and a little extra to add. First thing tomorrow, I will go to a local to me dealer of transmission materials which myself & Colin have used a few times now, Calda-Morley. Due to their fast turn around, we should have the new sprockets for next Sunday easily. Then I can pass on the information of the bore size to Colin as noted in previous post so the shaft can be adjusted if and as required. I've also got some different fuses to the currently installed ones too, as our newer ESC tops out at 60A per channel with a higher margin for short bursts of time, so we're going to replace the current motor fuses to ones of that value, as the motors we use shouldn't top 60A even for a burst. We still have another fuse between the batteries and {the rest of the electrics}, this is currently 200A, inline with the batteries maximum draw of 202A - despite all of the electrical components not drawing anywhere near 200A combined, I thought it'd still be better to give the option to draw more, up to the battery maximum rather than risk fusing what is essentially our master fuse for the entire bot.

Some images from today.

Securing our Zippy batteries with some Zippy ties!
IMG_20180211_130040.jpg

For the second consecutive weekend, we managed to break the workshop door.
IMG_20180211_132140.jpg

[team death]

This week we worked on the sprockets to increase the ratio for
the drive from 4 to 1 to 8 to 1 overall.
I had been working on the problem in my mind all week and with a
couple of failed practical experiments with bearings I had settled
on a wheelbarrow style bush/spindle support system.
Adam had ordered 2 new sprockets from calda morley with a bore
size of 12mm but when we looked at the sprockets they were much
smaller than the 12mm required so they needed work first off.

Earlier in the morning before this I had turned down the spindle to
support the 2 sprockets one of which I bought online and welded on
this onto the spindle.

One of the sprockets that Adam had brought was drilled out to fit the
spindle too and we had our 2 to 1 ratio-giving us 8 to 1 overall.
We had made one support bracket last week which needed slight modification
by means of a bush and housing welding to it and a second smaller version
bracket was made with bush/housing for the other side also.
This all seemed good and with the sprocket between the brackets it
seemed to line up well with the wheel and the motor sprockets.
There was a slight stiffness on the spindle in the bush but I narrowed this down
to the end cap of the spindle and I gave this a skim on the lathe after taking
Adam to the bus stop and it was a lot better.
I should be able to fit the chains beofre Adam comes over again and we can
see what difference these changes make.

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Some images to followup Colin's post yesterday evening, and even a gif this week!

Firstly, the lathe - Colin has spent a lot of time at the wheel of this over the past week, turning the poles for the new gearing stuff. Here one of the poles can be seen, after been turned somewhat already.
IMG_20180218_125206.jpg
Secondly, the completed reduction sprockets on their central mount.
IMG_20180218_135157.jpg
Thirdly, a quick gif which demonstrates the level of reduction from chain movements.

[team death]

IT'S ALIVE-ALIVE I TELL YOU!-A very good day on the Robot today, after realising
that the overall gearing to the drive from the motor was wrong at 4:1 we decided
to go for 8:1 and finished one of the reducer sprockets last week.
We usually have a four hour build session on a Sunday 12-4pm but to be sure of
getting any where near being able to test a new ratio set up I put some hours in
on Saturday and Sunday morning too.
On Saturday I turned down a length of bar using a old lawnmower cylinder
blade as the spindle to set the double sprockets on.
I then welded on the sprockets and added the end cap-I was very pleased with
the sprocket alignment, it was straight and true, two bushes were then set into
old sprockets as housings and they were welded to two brackets to support the
spindle / sprocket set up.
When Adam arrived with the half links he ordered on Sunday we were
able to fit the chains to both sets of reducer sprockets and it was time to test.

After a temporary wiring job we set the Robot on the patio and gave it a whirl-
needles to say we were more than pleased and I said to Adam "This is the champagne"
moment.
DSCN2082.jpgDSCN2083.jpg
1 lawnmomer blade used for metal
2 the reducer sprockets
3 Adam adjusting the motor wires

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And a little extra from me!
Also covered today, we replaced the blown out banana / bullet connectors from the old ESC blowout. This allowed us today for the first time in a while, not to resort to using bonding tape around one of the connections, and will help largely with a proper and stable electric circuit over bumps, as its possible this was a contributer to some of the problems.

But the moment we've all been waiting for, include myself and Colin. The robot alive, and moving in a manner we were both happy with!

At this point, we're both confident we're on the right track, and the only real challenge left we hope, will be working out the weapon and its motor, with the added sprockets for the 8:1 ratio limiting space internally a little. I'm sure we'll manage to find a way though.

[katch]

Well done lads.. I Did a test on mine today too must be the day for it

[team death]

In Readiness for this weeks Robot build I ordered a couple of clamps on e bay
and they arrived just in time for use this Sunday.
Unfortunately due to the bad weather, Adam was unable to come through this
weekend but hopes to make next Sunday.
During the week I had time to weld in place the retro fit sprocket to the winch
and managed once again to get it spot on straight.
Today I worked on the Jaws and a possible way to drive the winch sprocket
through the narrowed gap created by the drive reducer sprockets.
It turned out that there was just enough space at the side of the reducer strut to
run a line of chain up to the front mounted motor drive.
To make this idea work meant moving the winch drive motor to a more internal
position and thats where the clamps came in to support the motor.
Upon fitting the chain in place it looked like needing another half chain link, so
rather than settle for that I decided to enlarge the adjustment slots on the winch
so the chain could be easily adjusted.
Lastly-I noticed one of the drive reducer sprockets chains was slightly tight so
I slackened off the drive motor and added a metal shim under the clamp to lift
the motor and so give a little slack in the chain.
There are still the jaws to re fit but thats just a ten minute job and theres no
reason to think they wont work as well as before.
Next week we will probably concentrate on the electrics and get them to
competition standard.
Heres some photos showing the clamp and the chain from the winch up to
the winch drive motor.
DSCN2084.jpgDSCN2091.jpgDSCN2090 (2).jpg

[team death]

Todays build session was set aside for the electrical but unfortunatley
Adam was unavailable this week and a last minute change of plan was
needed.
I had noticed that the rear of the Robot was a little untidy and this was
clearly evident in the first video or the Robot moving around, so todays
plan was to tidy up the rear and discover if the cavity there would house
the switch gear for the jaws.
On inspection there was quite a lot of room in the gap and also there's a
convenient channel in the metal structure to run the wiring loom into.

The Rear of the Robot is probably the strongest part of the Bot-designed to
take the flip of a full pessure heavyweight flipper and also be resistant to
spinners-there may be shock issues with putting the electrics in there but
there is also plenty of room for foam padding.

I then welded the top of the rear of the Robot with some 3mm steel and
the lower (access) door was bolted on
DSCN2092.jpgDSCN2095.jpg
Picture 1-plate to cover gap
2 The rear cavity with a sample switch to show space
3 top view or Robot with plated piece showing

[Roboteernat]

Those fuse switches easily flip off, I would imagine a hit from anything would cause them to switch off... Would advise on replacing them with something more oh what's the word... It clicks and stays switched...

[team death]

Thank's Nat
The switches are just to show the area of space and will not be used in
the Robot.
When Adam returns I will talk to him about speed controllers and types
of switches.
We only need a simple on off really because the jaws need to close as fast as
possible and then we need a powered return so I'm looking at 80 amp
speed controlllers on Ranglebox but they have sold out-any suggestions
welcome.

[shakesc]

Have a look at

https://nutsandbots.co.uk/product/fe...-dual-channel/

https://nutsandbots.co.uk/product/fe...ingle-channel/

Should be fine as it looks like you are running on scooter motors

[Roboteernat]

The turnigy TZ85A are sold out from all suppliers, and according to hobbyking, will be back in stock in 3-4 weeks time now.
The ranglebox ones are the same but programmed to run as brushed motor drivers.

Shakey ones are lower amperage but as shakey says shoudl; work if using the right motors.
Otherwise there may be some avaiilable soon.
Hobbyking ones will need to be programmed yourself or by a fellow competitor. not sure what other options are available.