Here is my latest creation: a fully remote controlled Backhoe loader based on the JCB 4CX, which is a Backhoe loader with 4 equal-sized wheels & 4-wheel-steering.
Here's the video:
This model features a blend of Pneumatic & power-functions. It has:
* 4-wheel drive
* 4-wheel steering
* V6 engine
* Fully functional front-loader
* Fully funtional backhoe (including sideways-movement)
* Everything (even the lights) are remote controlled by a seperate remote controller.
For years, the 8455 was the standard in Lego Technic Backhoe loaders, but with the presence of the Power-functions system, I know it could be improved. So a specific Backhoe was chosen, in this case the JCB 4CX which was to be modelled. This is a Backhoe with 4 equal-sized wheels, which made the choice for the wheels a lot easier. Now the 8297 wheels could be used. And of course the 4-wheel-drive & 4-sheel steering had to be implemented.
For every function both pneumatic & electric systems were considered. Power functions have the advantage to be very controllable, but generally need quite some space and reliable drivetrains. Pneumatics are easier to construct and quite powerful, but are harder to controll.
While examining the 4CX, I noticed that its complete backhoe could move sideways. This was quie a challenge to recreate. A kind of rails was constructed to guide the moving backhoe. The M-motor which was used for the sideways-motion was placed inside the main body, and the M-motor for rotating the backhoe was placed in the first section of the backhoe.
The remote controller houses a compressor, air-pressure-regulator and all the switches for all the functions:
Quoting Bodo Hogrefe
very good, but I had no air hoses laid to Radio Control
There are 11 (!) fuctions being operated from the remote controller. Since the PF-system has up to 8 channels, the airhoses that connect to the remote were neccecary. But I agree that this air-hoseis a drawback.
The compressor seems to make a good amount of power and I like the range of motion for the front bucket. You did a great job getting so many functions into one model, the sliding rear boom is neat, I've never seen one like that. Overall very impressive.