Gareth

I started out in my working career as an Agricultural/Horticultural Engineer and was in the industry for 25 years; beginning as an apprentice Tractor Mechanic and working my way up to being a Research & Development Endurance Engineer for the world's largest Construction and Agricultural equipment manufacturer so I can understand what you are trying to achieve. However, there seems to be a few problems: being able to generate enough continual energy to complete the task, weight (remember that the operator is going to have to move the weight of the implements and still generate the energy to power them), Mechanical losses through bearings, gears, belts, sprockets and chains, etc. and being cycling related, quality, hard wearing and durable components are not cheap.

Light duty applications are doable: top dressing, spraying, thatch/moss raking, leaf sweeping, even light snow clearance, and minor tipping trailer work but that's about it.