The powered trailer/wagon is a practical and capable powered flat-bed or walled trolley we use around the yard or garden. It's quiet and clean and the powerful 500W electric drive takes the strain from moving those heavier garden loads. It has a front mounted, steerable traction unit that can drive in both forward and reverse and can be steered through a full 180° steering angle to give the trailer excellent  manoeuvring abilities. 

The wagon is small enough to fit through doorways and gates but large enough to carry much more compost or grass cuttings than my wheelbarrow and is a great help when cutting the grass, collecting leaves etc. Removable walls allow the wagon to be configured as a flat-bed trolley to accommodate low flat loads such as paving slabs, bags or sand etc, and with side walls attached it has a large capacity for carrying loose materials such as grass cuttings, fallen leaves or compost. The flat bed can be tipped manually for cleaning or to empty light loads although I'd have to add some powered lift capability to empty it with a full load of compost!

For easy operation I tried fitting the wagon with a finger operated wig-wag (joystick) type speed and direction control on the tiller handle. Operation can be either single or double handed. Properly built the wagon is suitable for lighter domestic garden or yard duties and has a load capacity of about 150Kgf (300lbs).

As with all the designs I tried to make it “buildable” by competent DIYers or home-builders using non-specialised tools and materials. The structure is mainly timber and uses a glued and screwed construction. Several key strength components are made of steel and throughout use is made of standard stock engineering components such as bearings, bright steel bar, gears,  sprockets etc. The drive gearbox is home-built too and is described in more detail here. It is efficient and reversible and provides some dynamic braking and slowing in use. The wagon's top speed is about 4  mph (brisk walking pace) and can be smoothly controlled in both forward and reverse to allow controlled positioning for loading or unloading. The total drive box power output is 500W from two DC PM 250W electric scooter motors each driving a 10” pneumatic front wheel. This drive arrangement allows sufficient differential speed action to allow the tight turning in use and the 10” wheels can handle most garden paths, small steps, lawns etc.

The electrical system is standard for small electric vehicles ie motors, motor controller, batteries and speed/direction/ignition controls. The choice of controller is largely the builder's but the controller used on this double motor trailer is the 24V 75 Amp Vortex controller from 4QD which has worked well. Room for two 12 V 38AmpH deep cycle batteries wired in series is built-in which give a generous continuous running time between charges.