Author: Marcia Franklin, director, Falcon At the recent National Ploughing Championships in Ratheniska, Co Laois, the Overall Winner of the Enterprise Ireland Innovation Arena Award was the Falcon Forwarder, the only Irish-built forestry forwarder. The awards recognise excellence in agri-innovation and 80 innovative Irish companies entered, of whom 30 were shortlisted as finalists. The Falcon F40 Mini-Forwarder is the first forestry forwarder of its type and class to be built in Ireland and the UK. Traditionally, very large costly forwarders were the only ones available and are not suitable for the small to medium woodland plantations that prevail in Ireland and some other European countries. Having identified key design criteria, we created a process plan for more effective use of our manufacturing resources. The design software used in the design and process planning of the F40 was Solid Works 2014. Every detail of the machine was drawn on Solid Works. The hydraulic components and engine were sent to us by the respective manufacturers in step format. Having these components allowed us to incorporate them into the model and incorporate them into a complete design. Stress analysis was also carried out throughout to identify areas where excessive stress may be applied. Thus, side plates and stiffener gussets were incorporated to overcome any applied stress identified. The structure of the F40 is simple, yet strong. High-tensile steel plate and structural box were used throughout the build. The cab and the trailer, known as the bunker, had to be strong, reliable and durable. Strength and durability were key in identifying the material that was used. The weight of the machine is critical to ensure its suitability for sites classed as 'sensitive'. The tyre choice was one of the first structural design aspects to be considered. The nominal ground pressure exerted had to be kept to a minimum to prevent soil structural and root damage.

Ground clearance

12Ground clearance of harvesting equipment is critical, as it must traverse difficult forest-floor conditions and tree stumps. The F40 was designed so that the required ground clearance of 550mm could be achieved. It uses four rocking bogies that also allow the machine to remain relatively level when travelling over uneven ground. The bogie is pivoted from an axle incorporated on the chassis. The bogies are narrow and strong, which is again important if travelling over ruts and stumps. The F40's low centre of gravity ensures steady movements on uneven terrain. With the narrow bogies and a track width of 2000mm a wide trailer frame was designed. Most of the bunkers load is centrally carried, therefore ensuring the centre of gravity is low. [caption id="attachment_16883" align="alignright" width="166"]3 The design has a low centre of gravity[/caption] The middle pivot joint from the cab to the bunker allows for horizontal steering and vertical twisting movements. There is a limit of ±15ᵒ for a weight transfer back to the cab chassis. The middle joint also steers left and right by ±45ᵒ through the use of two hydraulic rams. The F40, therefore, has a compact turning radius, which is key to its manoeuvrability and agility in a forest. With regard to cab design, the cab conforms to all safety regulations to ensure the safety of its driver. When working in woodland areas, the driver must have an unobstructed view in all directions. They must be able to see the forest floor and be able to watch the crane whilst working. The large curved front and back windows are a tinted polycarbonate safety glass. Its sophisticated look was designed for safety, so that trees, stumps, boulders and the contours of the forest floor can be easily seen. The cab was designed to be an independent component from the chassis. Maintenance is easily carried out as the cab hydraulically tilts to the side. Maintenance can therefore be carried out in the forest if required reducing production downtime. [caption id="attachment_16886" align="alignright" width="166"]4 Falcon cab[/caption] The cab seat can turn 180 degrees allowing the operator to drive forward or reverse with optimum visibility. There is plenty of leg room in both forward and reverse driving positions, after all the cab must be comfortable for long working hours. Steering of the machine, the crane and jack operation are handled by two joysticks which remove the need for a steering wheel or foot pedals increasing cab space for the operator. An air-cushioned seat, with height adjustment levels, a cab heater and fan and a USB radio are all included.

Falcon Forwarder power transmission

[caption id="attachment_16888" align="alignright" width="166"]6 The track system[/caption] The Falcon F40 is powered by a 49hp Kohler diesel engine, which won 'Diesel Engine of the Year' in 2012. It also keeps within the tier-three emission regulations and has the power to traverse difficult terrains with high torque at low revs. For ease of operation and to ensure competitiveness, it was decided to drive the machine hydraulically. The hydraulic system is primarily composed of three parts. The diesel combustion engine powers a hydraulic pump, which sends oil to the hydraulic motors that drive the machine and power the crane. Pressure loss is reduced with the larger diameter hoses that are used on the F40. Poclain Hydraulics has been chosen to supply the hydraulic pump and motors. Poclain has a proven track record, particularly with the supply of reliable pumps for equipment used on rugged terrains. It provided support in achieving maximum performance from the Falcon F40. A track option is available on the F40 as an optional extra. Different terrains and woodland types will require different tyretrack options. The tyre system includes eight 500mm-wide flotation tyres for minimal ground impact. The track system is manufactured from high-tensile steel plate, with chains to provide maximum floatation and traction. They are designed for increased performance and are strong to ensure a longer working life. Each track will incorporate two wheels together; it can be manufactured to suit the customer needs. A track with wide plates and narrow spacing is suited to soft ground, increasing contact area. A narrow plate with wider spacing is suited to hard ground and steeper slopes. The design team included Darragh Hand as head consulting engineer and Ray Flynn who managed and created the drawings using SolidWorks. See for more details.