Powered Technic Forage Harvester

Forage harvesters are essential on many farms. They are useful for cutting green crop (corn, grasses, etc.) and chopping it into silage for animal feed. Presented here is a Technic large scale version of a self-propelled forage harvester (there are smaller tractor-pulled versions, but this isn't it). Inspired by work I've done creating a large scale Technic combine harvester (separate Ideas submission), I turned my attention to another farm machine that's underrepresented in LEGO. This design takes advantage of new panels and parts released by LEGO in recent years to create a faithful rendition of the full-size prototype.

The design scale is based off of the same reference as my prior combine: the largest off-road tire available, which also is appropriate sized for older Technic figures. The design itself is based off of techniques learned from building many other LEGO creations. There is a solid substructure of liftarms and pins that support the internal mechanics and external paneling and features. The panels limit weight (vs. solid brick built) while following the essence of the prototype contours. Though not a perfect match, they capture the feel. The color scheme harkens to the New Holland brand Forage Cruiser. Exterior details include the detachable header (with mechanics detailed below), an operator cab with detailed interior including consoles and switch panels, rear hitch, and covered engine deck with chute support. The positionable discharge chute uses Technic gearing to be manually positioned by turning adjusting knobs. The header has 6 cutter heads that rotate in prototype-appropriate directions, all feeding into the center.

The internal mechanics makes use of the latest Technic Hub and motors. There are 4 powered features: 1) driving forward/reverse, 2) steering, 3) header raise/lower, and 4) header drive. With the Technic Hub, programming is done on a smart device via the Powered Up app. The drive and steering are straightforward. The header raise/lower makes use of Technic linear actuators to approximate hydraulic lift cylinders. Within the feeder (what the header attaches to) there is a small motor that powers a coupling going to the header. Via trial and testing, I've come up with an efficient means to power all of the cutter heads in prototype-correct directions.