INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

African Handcart: Innovative Designs

African Handcart: Innovative Designs

(OP)
Hello,

I am currently working with waste pickers in East Africa to pilot various designs for the standard hand/push cart, commonly used for the transport of goods and waste. At the moment I'm looking for specific input for the recommended PSI for tyres for different surface areas and loads. I'd like to calculate how to measure and fine tune this process. Specific details of the handcarts are below. A photo example of the handcarts is attached.

Handcart Carrying Area

W: 0.64
L: 1.82
H: 0.39

Wheel

0.57 wheel diameter, standard rubber car tyre

Average Holding Capacity/Weight

300kg

RE: African Handcart: Innovative Designs

The maximum inflation pressure for a tire is molded right into the sidewall. Why not start with that, or a few percent less, to provide a little safety factor for old tires?

Reducing the inflation pressure makes the tire ride more smoothly, but makes it harder to push on any normal (Western) road surface.

... probably also including deep sand. Off-roaders here commonly reduce tire pressure in sand, but it's done to reduce the ground pressure, not to make it easier to push.
... and off-roaders also carry compressors with which to restore proper pressure, something that's probably not in your budget.

For a test program, you'll need a compressor, a tire pressure gauge, a representative pushcart, a selection of typical surfaces, and a force gauge with which to measure the needed force. ... or just a calibrated arm.

... or maybe a rope, a snatch block, a tree, and some weights.




Mike Halloran
Pembroke Pines, FL, USA

RE: African Handcart: Innovative Designs

What problem are you trying to solve? Are the handcarts too hard to push? Tyres fail? ...?

RE: African Handcart: Innovative Designs

Star for MartinLe.

Josh, you are trying to improve a design that has been evolved over decades by severe economic pressure; there may not be any fat remaining in such a simple design.

Mike Halloran
Pembroke Pines, FL, USA

RE: African Handcart: Innovative Designs

Following on from MikeHalloran, probably he design is now refined as to what is the best compromise - the only improvement I can see that is likely to assist is a reduction in the overall weight - lighten up on the timber used - might only save a few kilos/ pounds but a save is a save when using human power.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close