Machine Shop Productions

Manufacturing in Motion

Team members Jose and Ryan with their work of art.

This week, manufacturing for several components were started:

• Digger brake
• drilling of digger plate
• Spindle
• material was cut
• Mounting bracket
• drilled
• mounted (as shown in picture)

To be done:

Tap upright and thread front axle to have spindle ready for welding.

Receive remaining material and begin prep work for welding.

Steering design Completed

Steering for the cart has been completed, allowing integration of the rest of the cart's components to be possible.

To-do:
Use the updated bill of materials to purchase materials for:

• Steering 
• Suspension
• Top frame

Spindle Static Analysis

Static Analysis of 500 lbs

Static Analysis of 600 lbs

Static Analysis of 700 lbs

Moving forward

This week was very informative as we conducted analysis on our spindle/axel set up. Further test will be done to confirm our results.

As we move forward, completion of the rear wheel assembly is needed in order to finish welding the base of our frame. 

Below is an image of a new bracket needed to complete this design.

Updated Gantt Chart

Welding Setback

This week, the team was set back on welding due to design. A few of the cart's components must be redesigned in order to continue welding:

• spindle
• suspension arms (possibly)
• reinforcement of front wheel (new design)

To-do:

Finalize design for mentioned components and run through our machinists (Mike and Joe) in order to proceed with welding.

Lauren the Machinist

Today, we have a special entry, as our team member Lauren learns how to use a mill.

 

Frame Material Purchased

With a completed cut plan, material(Aluminum 6061-T6) was ordered and cutting began almost immediately.

To do:
Prepare the aluminum by Wednesday and begin welding late this week, possibly Monday (10/14/13)

Bottom Frame Static Analysis

 

With the bottom frame finalized, static analysis was done to simulate a pulling force of 500 pounds.

The analysis produced the following results.

 

 

To do:

Further analysis will be on suspension

Create caliper mounting bracket if needed.

Buy material to begin welding frame.

Spindle Assembly

With the purchase of the disc brakes and calipers, the team encountered problems with the caliper's mounting bracket. A solution was proposed that would allow the mounting bracket to be attached to the entire frame via the designed spindle assembly.

Top Frame Of Cart On The Design Table

The team brainstormed a lot about the top of the frame. Things concerning the top frame that were discussed were:

• collapsible vs. detachable
• drill patterns
• overall design. 

To-do in the coming week.

• Talk to our school machinist (Mike and Joe) about a machining plan and where to buy material. 
• New bearings needed for the wheels and the top of the frame. 

Updated A-arm Set

The Buying Process Begins!

The weekend was very productive with several critical purchases being made. The items purchased were all four wheels/tires and brake assembly. A final base frame will be designed with the following dimensions in consideration.

• Diameter of wheels ~18 in
• Width of wheels with brake assembly ~ 4 in (2.94in wheels only)
• Axel diameter - 15mm

The top portion of the frame is also in the design process with generic lengths (will change with the final dimensions of the base). See below

In the week to come, the team will research the cost of material needed for the entire frame based on our design. 

Solid Model of A-Arms

CAD designs and drawings have been made for the A-arms. (subject to change with the addition of final dimensions)

Updated Gantt Chart

Click here to view Gantt Chart.

Updated PDS

Critical decisions

This week the team made a few critical decisions. With an updated gantt chart, the team realized they're were behind schedule therefore the following decisions were made.

1. Round tuning was thrown out and square tubing was chosen
   
   1.5 x 2 inch
2. Created a buying list for the following items:

• Wheels
• Brakes
• Tires
• Shock absorber
• Tie-rods

For the coming week, the teams plans to have items on the buying list on order by no later than Monday (Sept 16, 2013)

First Meeting of the 2nd Semester

The team met to discuss future plans on the mushing cart's construction as well as revisited the work that was done before the summer. With each individual teammate having a different schedule during the summer, a lot of scheduled items were pushed back. Therefore the team brought up topics that needed to be completed in order to get the building process in motion.

The team decided focus on the items that need to be purchased. A few items that will be purchased are:

• Wheels & Tires*

• Disc Brakes*

• Shock Absorbers*

*Items pictured may not be used in the final product.

Action Items

	Action Items: Entire Project		5/5/2013
	Task	Status	Lead
Sketch
	dimensions configured	DONE	all
	components chosen	DONE	all
	research	NA	all
Model (Solid Works)
	brake system	21-Jun	Ashley
	shock system	21-Jun	Jose
	steering system	21-Jun	Ryan
	frame	21-Jun	Lauren, Rochelle
	entire assembly	28-Jun
Analysis
	tubing	14-Jun	Lauren, Rochelle
	frame	21-Jun	Lauren, Rochelle
	entire assembly	28-Jun
Budget
	configure budget	DONE	all
generate parts list
	brake system	12-Jul	Ashley
	shock system	12-Jul	Jose
	steering system	12-Jul	Ryan
	frame	12-Jul	Lauren, Rochelle
get quotes for material
	brake system	26-Jul	Ashley
	shock system	26-Jul	Jose
	steering system	26-Jul	Ryan
	frame	26-Jul	Lauren, Rochelle
	fundraisers	TBD	all
	distribute funds	2-Aug
	generate Pos	16-Aug
Buy All Needed Parts
	brake system	30-Aug	Ashley
	shock system	30-Aug	Jose
	steering system	30-Aug	Ryan
	frame	30-Aug	Lauren, Rochelle
Assembly
Frame
	generate a machining plan	30-Aug
	machine all necessary parts	4-Oct
	Weld all necessary components	1-Nov
Steering
	machine all necessary parts	4-Oct
	assemble components	1-Nov
	integrate into final assembly	22-Nov
Brake System
	machine all necessary parts	4-Oct
	Assemble components	1-Nov
	Integrate into final assembly	22-Nov
Shock System
	machine all necessary parts	4-Oct
	assemble components	1-Nov
	integrate into final assembly	22-Nov
Final Assembly
	integrate all components together	22-Nov
	integrate collapsibility	22-Nov
	check for safety measures	22-Nov
Assembly Testing and Analysis
	define testing procedures	22-Nov
	run tests	6-Dec
	analyze test results	13-Dec
Final Report
	generate report	20-Dec	Rochelle
	generate presentation	20-Dec	Rochelle

Proposed Designs

The most completed system of the final design is the chassis.  It will be made out of 6061-T6 aluminum round tubing. A couple different diameters will be used to accommodate the different amounts of strength needed in each area, while remaining somewhat standardized. 

                The structure of the suspension will be made of hollow steel tie rods and will use rear bicycle shocks as the shock absorbers.  The specific lengths of the tie rods and the load capacity of the shock absorbers still need to be determined.

The steering system will also be comprised primarily of tie rods as well.  They form a four bar linkage to transfer rotation from bicycle handlebars in the back to the front.  At the front the front bar of the linkage will be connected to the wheel mounts.  Exact dimensions must be calculated to acquire the desired turning radius.

                The wheels and braking system will be primarily purchased.  The brakes will include a hydraulic disk brake on each wheel as well as a “digger” brake. 

                The collapsible portion of the cart still must be designed.  The primary function of this portion is to support the steering handlebars and provide something for the passenger to hold onto.  This will likely be made of some form of lightweight tubing, but dimensions and materials are yet to be determined.

Suspension

The current focus of the team at this moment is the suspension. The importance of the suspension is high, the team must establish a design that allow the user of the mushing cart to maneuver the vehicle safely from a rear position while all the pivoting wheels are located on the front of the cart.

After searching for ideas, the team was able to find an off-road handcycle used for extreme sports by the handicap.

Inspired by the design, the team hope to use this for their mushing cart with steering being possible from a rear position. 

Solid modeling has begun on the suspension system, and the team hopes to have those completed in the near future.

Updated WBS

Decision Making

Over the Spring break, the team met to make further decisions on the urban mushing cart. The following are possible options that we have narrowed down for the use of our chassis.

• Square vs. Round Tubing
• Thickness of material
• 4130 Alloy Steel (Chromoly) vs. 606-T6 Aluminum

Pros:

• Easier to weld

Cons:

• Load concentration areas

Pros:

• Cheap
• Widely Available

Cons:

• Harder to weld/bend

Future tasks

• Budget
• The team also spoke about funding for the cost of the material. The budget is currently $1000, but in the case that budget will be exceeded the team has determine that fundraising will be a necessity. The team has contacted fundraising coordinators at Warner Brothers Studios to attend TV show tapings in the event that more funds are needed.
  
• CAD
• A few things that the team will be working on in the following weeks is create rough CAD designs in order to get an idea of what materials will be more advantages. This task will also assist in determining what material and shape we should use when our CAD designs undergo static analysis. 

Finalizing the Design

The team set limits for components in order to prepare for narrowing the options of components in an attempt to finalize the design. Below is what the team established:

=

where,

1. Tires
2. Length of frame
3. Double barrel lever disk brakes
4. Height of frame
5. Steering
6. Suspension 
7. Digger brake
8. Hitch

The Decisions that were made were made the week of the (3/18/13) were:

• Tires
• Buy
• Size: 12-16 inches (in diameter)
• Frame (length & height)
• Build frame
• 6ft. x 3.5ft. x 3ft.(L x W x H) in approximation
• Brakes
• Buy
• Double barrel lever (disk brakes)
• On all four wheels
• Steering
• Make handlebars
• Buy handlebar grips
• Front steering
• Suspension
• Buying
• Front suspension
• Digger Brake
• Make
• Hitch
• Make
• Hook to carabiner

To be determine in the Following weeks:

With certain areas of the design still in a grey area, the team will work together to fully complete the design by establishing how the suspension will work together with the steering. The steering will also be looking into, currently the idea is to create a four-bar linkage that connect from the back to the front, in order to steer from the back. Finally the team will also finalize whether the cart will have both front and back suspension or just front suspension.

Urban Mushing Cart Visits The Team

The team gathered on campus to examine the client's own mushing cart to gather information and ideas on how to improve on their design.

Google Drive

https://drive.google.com/?tab=mo&authuser=0#my-drive

PDS

Attribute	Type	Metric/Requirement	Unit	Notes
Safe	Objective	# of ways to cause bodily harm
Resilliance	Objective	Varying impact and Temp.	Force/Temp.
Low-Cost	Objective	less than $1000	Dollars
Low-Weight	Objective	less then 85lb	Pounds
User Friendly	Objective	Ease of transport
Regulate Speed	Function	Accelerate as fast as dogs/80% efficiency
Regualte Direction	Function	Change alignment within 5 secods	Time
Decrease Speed	Function	Decelerate from 30-0MPH	MPH
		Stopping must range from 50-100ft	Feet
Stabalize Driver	Function	Reaction force must be less than 2/3 of impact force	lbf
Secure Passenger	Function	Hold lateral force of 500lbf	lbf
Attach Dogs	Function	Sustain tensile forces of 250lbf/dog	lbf
Transfer Energy	Function	Transer Kinetic Energy of at least 25%
Absorb Impact	Function	absorb 60lbf of impact	lbf
Prevent Damage	Function	Components must hold 60% of yield strength