Team Rock On Final Presentation

1
Team Rock On Final Presentation

• ME 4182
• Submitted 7/25/06
• Yuki Miyasaka, Anthony Palladino,
• David Price, Whitney Price, Ricky Sandhu

2
The Problem
Landscaping is a common enjoyment among
homeowners. Heavy boulders are very common on
property however, almost impossible to move. If
one wants to move a heavy rock, they have 2
choices 1. Use brute force and risk
hurting themselves. 2. Rent a bobcat,
figure out how to get it home, tear up the grass
moving it, etc. Neither option is
very easy or practical.
3
The Goal

• Create a cart capable of loading and unloading a
  large rock, and relocating it to different places
  within the yard. It would be designed to
  accommodate up to a 300 lb rock.
• Our idea would be marketed to the average
  homeowner with landscape needs. The individual
  could either rent or buy this device and easily
  store it in a garage or shed when not in use.

4
Original Design
5
Peer Input

• Q Why does the device not incorporate a wheel
  barrel or attach to a
• wheel barrel?
• A It is not sturdy enough and requires too high
  of a user input
• roughly 40-60 of total weight.
• Q What about the vast variety of rocks?
• A Redesigned strap system provides greater
  stability, a rock w/ a
• diameter 13 will work with the device.
• Q What if the rock is underground?
• A It doesnt matter because the spikes dig
  underneath. If the rock severely
• buried, shoveling around it will be
  required.
• Q Any specific design concerns?
• A To reduce friction on the wires, a sleeve
  bearing was incorporated into
• the design.

6
Changes Made to the Design

• Ratchet system moved higher for ergonomic
  purposes
• Sleeve bearing added to reduce friction on wire
  while pulling the load
• Step plate added to help leverage
• Strap system redesigned to be more adjustable
• A 2nd ratchet added to ensure better loading
• Finer details investigated such as materials and
  dimensions

7
The Final Design
8
Bending Moment of Prongs
Engineering Analysis

• Solid Round Shaft
• Safety Factor static loading
• Yield Strength Structural Steel ASTM 36
  58,000psi
• Using Safety Factor of 3
• Bending Moment 1500 lb-in
• Minimum diameter 0.92 in

9

• Tension Scenario 1
• Initially, the tension in the wire is 41.25lb

10
(No Transcript)
11
The Final Design

• The device consists of 5 subsystems
• Frame
• Ratchets
• Strap system
• Wheels/axle
• Pulley system

12
The Frame

• The frame is 48 tall and is made out of
  structural steel of 1 ¼ diameter and 1/8
  thickness
• All connections to the frame are welds

13
The Ratchet Subsystem

• Consists of two ratchets. The ratchets used are
  rated 2 ton.
• They were linked together to allow only one
  ratcheting action however, they are now separate
• Bolted to plate which is welded to the frame
• Connects to strap subsystem

14
The Strap Subsystem

• Made of polypropylene
• Has 2 sets of hooks to attach ratchet system to
  accommodate different diameters
• Hooks placed at 18 and 30

15
Wheel/Axle Subsystem

• Consists of 2 all terrain wheels
• 12 diameter
• Steel axle

16
The Pulley Subsystem

• Consists of a rod within a tube
• Tube is welded to cart
• Rod rotates to redirect tension
• Redesigned from traditional pulley system

17
The Prototype
18
Demonstration

• The Rock Mover in Action!

19
Design/Prototype Differences
Design Pulley System D shaped handle Ratchets interlocking Step plate or Hinge bar 1 round spikes Polypropylene Strap system Prototype Sleeve Bearing Bar handle No connecting bar No Step plate or Hinge bar ¾ hexagonal Chisels Wires used as strap
20
Future Improvements

• Wheel selection
• Remove step plate or allow it to fold out of the
  way for certain slopes of terrain
• Increase height of cart to increase leverage
• Refine the pulley system as the current design
  and prototype design are flawed
• Check for over engineering

21

• Questions?