Sariel.pl

Model of a Caterpillar articulated wheeled dozer. Features 4×4 drive, suspension, remote steering, remotely raised and tilted blade, lights and custom stickers.

Datasheet:

Completion date: 17/12/2008
Power: electric (Power Functions)
Dimensions:  length 57 studs / width 30 studs / height 22 studs
Weight:  1.73 kg
Suspension:  front – none / rear – pendular with shock absorbers
Motors: 4 x PF Medium

Another articulated Caterpillar vehicle. Partially similar to my earlier 990H front loader, but slightly larger and with different functionality. I wanted to use linear actuators instead of pneumatics, and that required more internal space that available inside a front loader. Therefore I decided to build a wheeled dozer, which offers more space inside the front hull’s part.

The drivetrain was simplier and more compact thanks to the use of new, 3-studs wide differentials. Only two motors were needed in the rear part of the hull, which could be therefore less massive and more realistic in size. The battery box was located in the same place, that is low behind the rear axle. It caused some problems with the weight distribution in case of the front loader, which did not have any heavy parts inside its front part. Here, another two motors were located above the front axle, so the weight distribution was much better.

The steering system was changed too. Earlier it was based on the horizontal 36-teeth gear braced in liftarms traversing the vehicle’s frame. This time, I wanted to try to save some space, and used a 12-teeth gear instead, with much weaker, yet more compact bracing. I was not satisified with the final result – the steering system worked, and supported model’s weight even when carried in hands, but the precision of steering was poor, and the central joint lacked stiffness.

As for the blade, I have attentively studied the construction and functionality of its real counterpart and decided to make it simplier and less functional. In the real 854G, the blade has the ability to turn to sides to a limited angle. Only a single hydraulic cylinder is needed to control this mechanism, but it meant that blade’s every point of attachment had to have two degrees of freedom. Thus the entire structure supporting the blade would become much more complex, and probably less rigid. Eventually, the blade was controlled by four actuators and turned out to be strong enough to lift the dozer’s front axle off the ground. The dozer performed reasonably well, except for the forementioned poor precision of steering. It could use a PF XL motor for drive to be able to push heavier loads, yet still the Medium motor provided a satisfactory torque.

The model was received much better than I expected. For me, it was merely a development of my earlier Caterpillar models, built partially for relaxation after the arduous work on the Colonial Marines APC model. Still, a considerable number of viewers expressed their accolade for the dozer.

Photos:

Video:

Media reference:

Focus.pl, TechnicBRICKs