156B Week 2

Overview of Status of Analysis, Design, Fabrication, Tests, etc.

• • The following design decisions/changes were made based on individual component analysis and hardware testing results:

    • 2-wheel cart --> 4-wheel cart

    • front 2 wheels are to be swivel wheels for frame stability

    • 80/20 frame --> Telescoping push-button frame

Accomplishments from Previous Week

• • Research performed and consultation with industry wheelchair manufacturers on design.

  • Critical measurements of client: Bodie's weight, fold-of-flank (rear leg height), body width, etc.

  • Explored over a half dozen mechanism ideas for sit-stand and are in the process of weighing viability

Goals for Next Week (list names after each item). Use specific and measurable objectives.

• • Research remaining design decisions by calling industry wheelchair makers.

    • Frame - method of fastening parts, material, diameter (Elias)

  • Front swivel wheels - size, angle, location (Ming Ming)

  • Sit/stand mechanism - motorized vs mechanical, hinge/pivot vs scissor lift vs spring (Aryan)

  • Order parts: (Sherman)

    • New frame 

    • Frame brackets

    • Part fasteners

    • Swivel wheels

  • CAD models of feasible sit/stand mechanism, of final proposed design. (Team)

Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)

• • Dr. Yu wanted to see more ideation and discussion of alternative solutions. (12/16, in person) 

  • Dr. Yu approved and supported design decisions/changes (4-wheel, new frame) pitched by team. (1/13, in person) 

• Note: Dr. Yu prefers to be billed cumulatively at the end of the quarter with shared access to team's up-to-date budget sheet. (1/13, in person) 

Instructor Comments from Last Meeting and Actions Taken to Address these Comments  (indicate date of comments and if via email or in person)

• • Stay focused on advancing our design process, and don't have analysis paralysis. (in person, 1/10)

  • If the idea doesn't seem like it will work, don't pursue it further. Previous year's team wasted time doing this. (in person, 1/10)

  • Find a more objective way of gauging Bodie's comfort (his visual excitement is a good start). (in person, 1/10)

  • Look at previous year's team's work once given access (CAD). (in person, 1/10)

  • When doing FBD, do vector form rather than x&y components. (in person, 1/10)

Comments from Other Students in the Class (indicate date of comments and if via email or in person)

• • none

Risks and Areas of Concern

• • Parts not arriving in time.

  • Having our mechanism for sit-stand not be a wow solution (currently none of them stand out).

Resources or Information Required but not Available

• • none

Schedule

• • 1/14-1/18: Draft sketches and CAD models for sit/stand solutions. Research, consult with industry dog wheelchair manufacturers (Walkin’ Wheels, K9 Carts) on how dog weight impacts wheel size, how to orient wheels. Order frame, wheel, etc.

  • 1/21-1/25: Fabricate frame, wheels, and wheel struts in shop; set up hardware testing test bed and parameters. Order parts for sit/stand system; fabricate in machine shop. 

  • 1/28-2/1: Hardware testing of frame, wheels, sit/stand.

• Update Gantt chart. <-----We need this

Budget (list amount spent and amount remaining)

• • 4x 8020 extrusion bars--$41.39

  • Loop Clamps--$12.00

  • corner brackets--$29.05

  • Home Depot trip for screws--$4.94

  • Amount Remaining: $2512.62 (out of $2600)

Progress on Report and Webpage

• • none, will work on after presentation on 1/17