Superway Spring 2016 summary: II (Intermediate) Bogey

II Intermediate Bogey

Background and context for the work of the sub-team

Description of the subteam and objectives

i. Redesign for traversing +- 17 degree guideway

ii. Design of fail-safe mechanism in case of falling

iii. Re-design the bogie and h-bar to integrate all supporting teams (propulsion, steering, braking, guideway, suspension, wayside power, and cabin)

Design Requirements and Specifications for the Sub-team’ s Work Products

Bogie must have multiple fail-safe mechanisms for the following situations: Falling straight down/Falling to the left or right
Fail-safe mechanisms must be mechanical and operate without the usage of sensors and/or power
-Each fail-safe mechanism must be able to hold 300lbs(weight of whole bogie and cabin)
-Bogie must be able to traverse up and down a guideway sloped at ±17° (30% grade)
Bogie must have at least a safety factor of 2

State-of-the-Art/Literature Review for the Sub-team’ s Sphere of Work

Fail-safe mechanisms for project were analyzed based on roller coaster designs (only designs that deal with suspended transport)
Chain dog used as fail safe mechanism (consists of Ratchet and Pawl)
This design concept was not implemented since the braking system was not enough to keep it from moving backwards
Friction wheels also used
Able to stay on track from all directions, allowing for complete fail-safe
Stabilizes incline and decline

Description of Your Design

Fully mechanical safety system (No need for external systems that could be subject to power loss)
Upstop wheel placed on static portion of bogie (stabilizes bogie during incline/decline)
The solid catches are fastened on to the top and bottom of the bogie
If the object falls vertically, then the bottom catch will hit the bottom track
Cutches are not too long to interfere with the guideway
Since the guideway now has a slope of 17 degrees, superway H-bar now must require 2 degrees of freedom
U-joints were designed to allow for horizontal and vertical travel between bogies
Bogie now like 4 bar mechanism
U-joints allow for incline, decline, and turns
Hub motor moved between half-bogies
H-bar constructed using 1”x1” 11 GA A36 steel square tubing
90° angle bar was cut and welded in for additional support
Total length of H-bar is now 30” to accommodate for space needed for actuators
Bogies were fabricated using ǩ” thick A36 steel
1”x1” 11GA A36 steel square tubing was usedfor structure of the frame of the bogie
The six square tubes provide support for the bogie as well as mounting holes for the eight wheels needed
All structures were MIG welded together

Analysis/Validation/Testing

Every part simulated with load of 300 lbs (maximum load)
A36 steel was chosen as material
Upper catches suggest that materials and dimensions would produce a safety factor of 3.5
U-joints tested by connecting both half-bogies/connecting bars→ simulating movement that would be experienced while traveling in slops and turns
U-joints + Bogie were able to fully support load conditions without failing

Money Spent on Project

Results and Discussion

i. load wheel on top of the lower rail on the guideway

ii. 6 inner wheels that roll on inner sides of guideway rails

iii. 2 upstop wheels that roll underneath guideway

iv. Steering mechanism that rolls on outer sides of upper rail of the guideway (Locking Bogie in all directions)

- If any of these wheels fail, then the upper/lower catches will prevent bogie from falling/derailing

Conclusions and Suggestions for Future Work

Superway Spring 2016 summary