Technical Details

The eBarrow Kit that you see here in the photos and videos (the one with the square battery box) is a fully functional prototype that has been put through rigorous testing in my own yard for over a year prior to initiating our Kickstarter campaign to fund the development process of the commercial unit.  Here are some testing results:

 

• The battery lasts for days of occasional yard work without charging. Battery capacity is 10Ah, which is about 5 times that of the plug in batteries you get for weed whackers or hand drills.  Please see battery capacity description and the battery testing video.

• The motor is so powerfull that it has never failed me in hauling any heavy load up the slopes on my property.  It is a fully sealed gear motor that generates 35 N.m of torque (26 ft.lb).  With a 14" wheel and a deep tread, I've never had problems climbing hills with a heavy load. Check out the testimonial video from a happy user here.

•  The bracket fits all the commonly sold wheelbarrows here in the US, that are sold at Home Depot or other hardware stores.  If the wheel is mounted with 4 bolts, this kit will fit.  If you are unsure, just measure the brackets and compare this to the technical requirements in the Installation section.

• The case is waterproof to the IP67 standard.  It has protective bumpers in front and below, and after 6 months of hard use in the backyard, nothing has broken or fallen apart.  The square blue box that you see in some of the older videos is the original prototype case, 3D printed in my basement. As you can see from the current photos, the component case used in the commercial version is far more elegant.  The commercial version also features a revised support bracket with enhanced bumpers that protect the case against collision and rough handling.

• The system also employs a number of clever design features.  For example, the bracket not only supports the battery case but also acts as the heat sink for the motor controller.  The heat generated by the MOSFETs during operation is conducted directly to the bracket which then acts as the heat exchanger.  That way, the case does not need vents and can be completely sealed against moisture, yet still enable the internal heat to be rapidly conducted to the outside environment.

• The tire was developed specially for the eBarrow. Initial testing was done with conventional air filled tires.  But along the way it became clear that punctures and leaks can develop.  Indeed, my old wheelbarrow tire needed to be filled up at least once a month.  But new technologies allow solid polyurethane tires to be moulded to any shape and tread design.  The new tire therefore has a wide and deep tread for grips and stance on soft ground, yet is completely puncture resistant when used in a construction site where there is the potential of nails and other sharp objects.

• The version with the more rounded, motorcycle-style battery box and the solid rubber tire is the final, much improved version that is being offered for sale. Click here to view the model in 3D.