ENME400 Machine Design
Studio Problem 2 – Free Body Diagram and Stress Calculations
Description
For the proposed design cart from Studio Problem 1, teams conduct stress analysis and design the
layout of shaft(s) including the locations of bearing(s), gear(s) and wheels when necessary. For
calculations, consider shaft diameter of 25 mm.
• Determine the minimum required torque on the driving shaft(s) using acceleration calculations
• Draw free body diagram of shafts
• Determine the reaction forces and torques on the shafts
• Determine the location and magnitude of the greatest tensile, compressive, and the shear
stresses in the shaft; use a two-plane analysis if needed (see example 3-9 from the textbook).
• Draw shear and bending moment diagrams for each shaft
• Document each student’s contribution to this assignment
Objective
Students will develop an appropriate understanding of stress analysis, shaft design and find reaction
forces using equili
ium equations.
Submission
Each team will submit their assignment through Canvas in PDF format.
Ru
ic
10 points for torque and acceleration calculations
20 points for free body diagram of shafts (at least two shafts)
20 points for reaction forces and torques on the shafts
20 points for location and magnitude of maximum tensile, compressive, and the shear stresses
20 points for shear and bending moment diagrams for each shaft
5 points for student’s contribution documentation
5 points for professionalism and well-articulated submission (clear, concise, coherent, complete)
Microsoft Word - Studio Assignment 1
ENME400 Machine Design
Studio Problem 1 – Problem Definition and Requirements
Description
Each team will meet to document team contract using provided outline. Teams review the design
project posted on Canvas under Files > Design Project folder.
Document team contract using provided outline
From the project description, students are to document a list of requirements or design
specifications. The requirements should be a clear and complete sentence.
Students will provide a possible concept solution for the problem. It could be an abstract hand‐
sketch or a CAD model with some text explaining the solution. No calculations or detailed design
specifications are expected for this assignment.
Finally, students will write about the general design process and the type of analysis that are
needed to solve this problem.
Document each student’s contribution to this assignment
Objective
Students will develop a high level of understanding of the Design Project and possible solutions.
Submission
Teams will submit typed assignment through Canvas in PDF format.
Ru
ic
Professionalism will be considered in the grading and can result in a maximum of 20 points off the final
score. Professionalism includes but is not limited to co
ect spelling, proper grammar, proper
formatting, clear display of information, and inclusion of document metadata (name, date, course,
document topic, page number).
10 points for a complete team contract
20 points for complete list of requirements (minimum of 10 requirements)
25 points for a hand‐sketch or CAD model with some text explaining the solution
20 points for general process and analysis type
20 points for professionalism and typed, well‐articulated submission (clear, concise, coherent, complete)
5 student’s contribution documentation
Shaft FBD
X
Y
.1m.025m
Wheel
Axle Shaft
Cart
Axle Bearing
Z
Y
.025m
Wheel
Axle Shaft
.1m
.025m
.075m
Cart
.3m
Axle Attaches
to differential
Z
Y
.025m
Wheel
Axle Shaft
.1m
.025m
.035m
.0125m
.3m
Z
Y
Axle ShaftAxle Bearing
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2/16 Studio Submission
During the class today, we completed the acceleration and torque calculations on wheels using
Kinematic equations and then related Newton's first law equations. As a result, we achieved
values that seemed reasonable given the slow speed of the car, around XXXXXXXXXXN-m on each
wheel, with a wheel radius of 0.05 m . Towards the end of class, we reevaluated our chosen
wheel diameter, based on the amount of space needed below the car. After some deliberation,
we believe that the wheel diameter of .1 m was realistic, there will be some clearance between
the wheel and the bottom of the cart, this should allow for the gea
ox and motor to be
approximately 0.06 m thick, leaving 0.05 m between the bottom of these and the ground. We
also establish the total number of shafts to be 5, with an input shaft into the gear box, a layshaft
inside the gea
ox, the output shaft, then two shafts to the two rear wheels to power the cart.