Transcript Stair Stepper Mechanism Innovated design

Stair Stepper
Mechanism
Innovated design
Jarrett Johnson
Advisor: Cris Koutsougeras
Instructor: Cris Koutsougeras
Et 493 - Senior Design
Fall 2013
Introduction
Stair steppers continue to be popular options for home exercise. They offer the same
benefits as running stairs, but with the "any time, in any weather, without having to leave the
comfort and safety of your home" added convenience. They don't take up much space, require
moderate balance and coordination, and can provide an effective workout for all levels of
users, from beginners to serious competitors. Like most exercise equipment, stair steppers
have come a long way, technically speaking. Advanced computers on most newer models
allow users to track their vitals at a glance. However, the most important benefits of stair
steppers are still the basic ways they provide excellent cardiovascular workouts that get the
heart pounding, along with the impact the exercise has on muscle tone in the legs, thighs, and
buttocks.
Objectives
The main objective of my project is to design an exercise mechanism that will
allow the foot to achieve natural motion during operation. Some challenges are
that I need to create an optimal design that will require low maintenance and be
durable while keeping the cost to a minimum. I will use computer simulation to
prove that the design will operate efficiently.
Mechanics Of Stair
Negotiation
2 quantitative domains

Kinematics- detailed description of motion

Kinetics – understand the causes of motion
Kinetics

Inverse Dynamics – to derive the forces and moments from
kinematic equations and parameters of body segment analysis

Use Newton’s Laws of Motion


Divide lower extremities of body into segments and make FBDs
Support moments – to show effects of all moments of lower
extremities during support phases of ambulation

Joint power analysis – to determine the contributions of each
joint’s moment of force to the overall mechanical energy of the
body
Kinetic Analysis
Kinematic Analysis

Linear Position

Linear Acceleration

Angular Position
COMSOL MULTIPHYSICS
Similar to AutoCAD but also has a FEA(finite element
analysis) software built in
Fall 2013
•
Study biomechanical engineering and kinematics to determine
muscle groups used in order to specify design components to
meet criteria based on average physical ability, height, weight.
Etc.
•Study
and understand natural ambulation (walking stairs) and
develop a mechanical system to simulate the process
•
provide graphical representation of projected design
Elliptical Design
Elliptical system uses system of links to prevent the foot pedals
from moving side to side or sliding back and forth while allowing the
machine to operate in an elliptical motion. A well designed and tested
system will provide an adequate amount of support to the feet while
allowing the user to feel comfortable and safe while attaining a good
workout.
Adjustable Design
An adjustable design to better equip users of different sizes and
physical abilities. The design will easily accommodate a range of
different workouts that will all target the same muscle group for users
of different sizes.
Timeline
October 25- Presentation/Proposal
October 31- begin stress analysis calculations
November 5- have the stress analysis calculations completed
November 15- formulate design based on calculations
Thanksgiving Break- have the design complete and start presentation
December 3 – finish final presentation