Is there any 5+R (maybe with +N) sequential remote controllable gearbox?

[bekesizoltan]

Hi,

I'm looking for a reliable remote controllable 5+R sequential gearbox or ideas how to build one. If it would have a neutral as well it would be perfect.

Please share your ideas and if you are aware of any kind of existing solution please share the link.

Thanks,

Zoltan

[Alex Ilea]

Sheepo is the master (but instructions cost money)

[aeh5040]

I'm guessing the index mechanism from Didumos's Hammerhead would be a good place to start:

 

[Splat]

I have a few videos on my YouTube Channel:

Lego Technic Smooth Linear Gearbox - 6 Speed + Reverse
Read the video description for more information.

With 6 Speeds + Reverse, the gearbox ends up quite big though.

A neutral gear can also be added, as shown in my 3 Speed + Neutral + PTO version of this gearbox:

Lego Technic Smooth Linear Gearbox - 3 Speed + Neutral + PTO
Again, check the video description for more information.

[TheMindGarage]

Sheepo has some good ones, but instructions are expensive.

5+R is a very difficult combination to build because you need three driving rings. Would a straight-8 (8 forward, no reverse) be an option? That would be easier because you can make a 4-speed sequential connected to a 2-speed (I recommend having the 2-speed's gear ratio difference around 1:1.25 - this can be done with a 16-tooth and a 20-tooth).

[Didumos69]

Al though Sheepo's geatboxes are well known and impressive, the master himself reports on correct speeds change ratios of 85-95%. I would personally never settle for such a high fault rate.

There are better shifters out there these days that can be motorized quite easily. I know @DugaldIC has motorized a modified version of my shifter. Something similar should be doable for the shiftera in @Jeroen Ottens DB11. His 8-speed sequential is also a serie of a 4-speed and a 2-speed.

[DugaldIC]

I was looking into this recently as well, one thing I noticed was due to shifting options there's no easy way to motorize a 5+R gearbox. I settled for a four speed forward but wasn't happy with any gearboxes I came across and made my own compact four speed with a modified version of Didumos 90° limiter.

1 hour ago, Didumos69 said:

reports on correct speeds change ratios of 85-95%. I know @DugaldIC has motorized a modified version of my shifter. Something similar should be doable for the shifter in @Jeroen Ottens8speed

However I'd have to say I have about the same issue Sheepo has with the driving/shifting rate, it's not perfect unfortunately. Your best bet for sequential is a four speed or if you'd like to get fancy an 8 speed due to the limitations of Lego shifting capabilities! Unfortunately I don't have ldd of my shifter otherwise I'd say try it out. 

Edited April 17, 2017 by DugaldIC

[bekesizoltan]

The best candidate I have found on youtube is 

 

[StudRobotics]

I'm having this issue too. After months I'm still trying to find the right gearbox like this (except four-speed) for my GX EV3. I tried Sariel's 4-speed sequential that's shifted by remote control and modified it many times, but it only resulted in high complexity and lots of gear grinding while the car was moving.

[Rikus]

Sheepo 4 speed sequential mini-gearbox and 7 speed sequential gearbox are free to download, actually.

Another good starting point can be Sariel's ultra-compact 4 speed sequential gearbox... free instructions as well.