Spur II build

[shakesc]

Well this was Spur. It was my first featherweight and in general happy with it



Good points
- Chassis was solid. It used 10mm HDPE but the corners were joined with angle iron and had a 3mm base. You didn't want to drop it on your toe!
- Traction. It used 4 drill motors with 100mm blue wheels with mountain bike tyre. The tyre had a nice open tread and wear rate was low
- Its a lifter and the linear actuator was very powerful

Bad points
- The wheels were exposed so vulnerable. It got slipped once landing on a wheel wrecking the gearbox
- Linear actuators have no give. So landing on the forks meant the forces had to go somewhere. Generally into bending the forks

So after getting my axe robot into a working state, and learning a bunch from steel chassis bots, I have decided to build a new Spur imaginatively called Spur II

I wanted to keep the bot nice and small. This allows me to use weight in a more flexible manner.

Key objectives
- good traction
- protected wheels
- strong lift but able to withstand shocks i.e. flips
- able to go full combat

[shakesc]

Re: Spur II build

Steel is more unforgiving so went for drawing and templating the steel before cutting

[shakesc]

Re: Spur II build

So this is the basic layout



Its tight inside but enough space for the important bits

[shakesc]

Re: Spur II build

I've got the steel templates cutout

Currently 4mm Hardox sides. The chassis plate is 3mm but looking to move to 4mm as well




Just need to buy a welder to put it together

[shakesc]

Re: Spur II build

The lift motor is from an AEG 18V cordless drill I picked up cheap from ebay
Its a monster but the gearbox is 2 speed and general quality seems very good
I'm building this on a self contained frame for maintenance. It will chain drive the front end lifter mechanism

[plargen]

Re: Spur II build

have you left enough space for the esc's

[shakesc]

Re: Spur II build

Yep - 3 TZ85a. They line up nicely under the battery
I might move one under the lifter motor. Enough wiggle room to decide in a bit

[Eventorizon]

Re: Spur II build

How is the AEG 18V getting its power to the forks? There seems to be very little space

[shakesc]

Re: Spur II build

Chain and sprocket

A 14 tooth sprocket on the motor (welding onto the shaft)
The lifter will be a 17mm shaft running in needle bearings with sprocket welded on there again

[Max]

Re: Spur II build

So will the chain go around one of the Gimson drive motors?

[shakesc]

Re: Spur II build

Yes, might need to get some guides in place but the larger sprocket on the lifter helps and the rotation of the chain is minimal

[shakesc]

Got the basics of the chassis welded up.

[psychostorm]

That looks familiar.

[shakesc]

Well done some welding. Internal bracing is in. This is the basic layout. Can squeeze 4 GR02's , 1 huge lifter motor and gearbox plus a decent sized battery. Will have 3 hacked TZ85a's.

The control for the lifter is going to be electronic through a Arduino Nano. I've been developing the code for axe control and decided that a few small mods it can be used for a lifter including torque control. This allows me to remove the need, and weight, for a mechanical torque lifter. Shame I decided this after I bought the mechanical control

[typhoon_driver]

So that's what that shaft was for. I did wonder why you only needed one.