Gimson Robotics

[Ellis]

Re: Gimson Robotics

They really look fab. And for the price they'll be brilliant. But, as Gary sort of said, I fear the shaft being unsupported like that may cause problems. Not sure if it's now just one bearing in the front or two smaller ones or something, but a less supportive bearing setup and the leverage aspect of having a longer unsupported shaft could become an issue?

I realise you can support on the other side of the shaft to help with this, but if these are still mostly aimed at beginners then that sort of thing is beyond many. If it can't simply be screwed in with a wheel bashed on then I can see people being put off.

But, time will tell. Might well be fine. The two reduction options is very interesting.

[shakesc]

Re: Gimson Robotics

Ewan - rather than flats (which with a bench grinder / angle grinder you can do) did you consider keyways?

[ewan]

Re: Gimson Robotics

It's a single bearing this time just behind the front aluminium face. The dual bearings previously did indeed provide good support but there wasn't any real flexibility for mounting, I don't know anyone who didn't mount on the end of the threaded portion (which was the design intention), whereas with the GR02 the idea is that multiple mounting positions are now possible. This arrangement is similar to the Banebots gearboxes in the US, and just as they do I will be putting in the product documentation disclaimers against users placing large loads on the end of an unsupported shaft, as well as guides for good mounting practices. If you mounted close to the front face you'd be very unlikely to need additional support at the end, and if you did mount at the end, as I've said before, incorporating support at the beginning of the shaft can be as simple as adding a bulkhead-supported bearing to the first few millimetres of the shaft (rather than having to implement outer support).

The target for these motors isn't really beginner roboteers - that would narrow the market scope far too much especially as so many of them go down the 'must get the cheapest option' route these days and some even considered the GR01 expensive. The addition of a shaft flat follows this thinking by targeting users of other hobby and industrial planetary gearmotors where this is a standard option, certainly fitting sprockets/gears/pulleys will be more straightforward.

A keyway was considered but found to be both more expensive to implement and potentially too weakening to the 12mm shaft section whose final few millimetres coincides with the left-hand centre-bore.

[Eventorizon]

Re: Gimson Robotics

Are the mounting points in the same place as in the GR01's? So the same depth and width apart and M5 Bolts?

[ewan]

Re: Gimson Robotics

The distance between the hole-centres is slightly narrower at 18mm (from 19mm previously) and the distance between the front and rear holes is now 29.5mm (from 41.5mm)

[Eventorizon]

Re: Gimson Robotics

Tolerances? The GR01's were + 1mm if I remember right

[ewan]

Re: Gimson Robotics

At very worst these are +/-0.1mm on part dimensions or +/-0.2mm on overall dimensions such as the distance from front to rear section mounting holes. It's a big step-up in precision from the GR01's

[maddox10]

Re: Gimson Robotics

So, enlarging the 2 front holes, redrilling the 2 aft holes, adding some washers and shorten the axle should make it a 1 on 1 replacement for the GR01.

[Eventorizon]

Re: Gimson Robotics

Shame both Conker II and Binky were water jet cut to match the GR01's, we are going to have to re drill those beautifully cut bases now

[Max]

Re: Gimson Robotics

Shame both Conker II and Binky were water jet cut to match the GR01's, we are going to have to re drill those beautifully cut bases now

Or try to find some second hand ones

[archie2000]

Re: Gimson Robotics

or make some different gr-02 mounts

[ewan]

Re: Gimson Robotics

Progress is being made, the shafts should be finished by Tuesday then gearbox assembly will begin in earnest.

[ewan]

Re: Gimson Robotics

Having costed up the options we will be offering an external bearing kit for the GR02 for those who want to place a load or wheel on the end of the shaft but don't have bulkheads in which to put a support bearing. The bearing block itself may of course be used separately from the GR02 as well.

Apologies for the appallingly coloured render(!):

[Ellis]

Re: Gimson Robotics

That I like. Really good idea. Makes the whole product more flexible (not like that!) and brings them back into line for replacing drills.

[Bodge Job]

Re: Gimson Robotics

Aha while I was reading though this I was thinking of suggesting that, but I guess you already had thought of it! And they look great though, may have to finally invest in a bruiser 1 upgrade, considering we break at least 1 drill gearbox and motor every event it may just become cheaper in the long run to replace them with those, plus the different ratios looks interesting means I could get more speed using 4wd!