Orbital Scythe Prototype

This page updated January 19, 2005.

O-Sage Power Equipment LLC

Orbital Scythe Prototype

Technology and Innovation
The product is a lawn mower which is substantially more energy-efficient than standard rotary mowers and, in contrast to existing reel mowers, has an inherent capacity to mulch grass. Two key innovations make this possible.
The first is the placement of multiple (two or more) cutting blades inside a slotted, cylindrical reel. The blades and the reel counter-rotate. This counter-rotation creates the mulching action - each blade of grass is cut progressively shorter as the blades pass over each reel bar in sequence. This mulching action is in contrast to all other mulching systems in that the grass in mulched immediately as it is first cut, as opposed to the clippings being recut in the air around a spinning blade. This makes the mulching function predictable and reliable.
The second innovation is the use of thin resilient blades which make sliding contact with the inside surface of the reel cylinder at an acute angle. The grass is sheared at the sliding point of contact between a blade and reel bar, which accounts for the energy-efficient scissors-like cutting action. This arrangement creates a clean cut at the top of the grass (which is good for the health of the lawn), and requires less than 25% of the energy consumed by a similarly-sized rotary mower. This intrinsic energy efficiency enables the cutting mechanism to be operated by a relatively small battery-powered electric motor.
Emission Benefit
The substitution of a 1 hp four-cycle gas engine for an 8 hp two-cycle engine could potentially produce an order of magnitude reduction in the fossil fuel based air pollution generated by such mowers. Proportionately less CO2 would also be produced. The mulching action of the new cutting mechanism also means clippings can remain on the lawn. This sort of "grass-cycling" minimizes the danger of methane generation during anaerobic fermentation - either in a landfill or the user's compost pile.
Project Descriptioin
Based on testing with the "proof-of-concept" prototypes, both the cutting mechanism and the supporting mower (frame, wheels, powertrain, etc.) have been redesigned for better operability, durability, and manufacturability. Also, the original prototype was user-propelled. The goal now is to build self-propelled versions, both electric and gas-powered, and test each for 100 to 200 hours on a variety of grass species. At least one of the units will be tested for 500 hours. An additional non-self-propelled, ultra-light unit is also under development. The goal is to demonstrate that both user- and self-propelled designs are capable of carrying a two-year residential-use warranty, as well as demonstrating the practicality of a unique self-propelled cordless electric mower.

Funding Source

Funding Amount





Weld-Rite Services

$  2,000

ICAT Funded Projects