Gate 2: Product Dissection - Harley-Davidson® Rocker™ Power Wheels

From GICL Wiki
Revision as of 00:44, 18 December 2010 by MAE 277 2010 Group 25 (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Contents

Project Management: Preliminary Project Review

Cause for Corrective Action:

Our original management plans consisted of a combination of the Gantt Chart posted in Gate 1 and a Google calendar outlining due dates and meeting times. We also assigned specific jobs to the different group members (shown in the Group Member Details Chart in Gate 1). So far our original management plan has run smoothly with respect to the deadlines for the different parts of the project. Otherwise, we have run into a few major problems concerning group meetings and our original conflict resolution plan. Because of the scheduling conflicts we have had difficulty meeting as a group.

Problem: People have had difficulty attending the mandatory meeting on Saturdays. So far we have not had one Saturday meeting with all group members in attendance. Because of the poor showing to the Saturday meetings, conflicts have gone unresolved.
Solution: As of right now, we are going to attempt one more Saturday meeting, and depending on the attendance to that meeting we will either keep the mandatory meetings on Saturday or move them to Fridays after class. After class on Fridays, all group members have no scheduling conflicts, therefore we all have nearly no excuse for not being able to come to the meeting. The group members can also be directly confronted if any one of them cannot or have not been going to the meeting.

Product Archaeology: Product Dissection

Disassembly Steps

*Ease of Disassembly Scale is below the disassembly steps.

*Anything without "Not Meant to be Disassembled" is meant to be disassembled.

Step # Step Time (min) Ease of Disassembly Tools Used Image
1 Remove the 2 screws attaching the seat assembly to the fender and remove the 4 phillips head screws, disassembling the seat and its bottom piece. 1:10 2 3/16" Phillips Screwdriver 1dis.jpg
2 Remove the phillips head screw keeping the battery retainer in place and the battery retainer. 0:10 1 3/16" Phillips Screwdriver 2dis.jpg
3 Remove the battery and detach it from the cable connecting the battery to the motor. 0:10 1 None 3dis.jpg
4 Removing 8 phillips head screws, 4 from each side, detach the headlight and the left and right headlight retainers. 1:52 2 3/16" Phillips Screwdriver 4dis.jpg
5 Detach the handle bar and the handle bar retainer from the top part of the front fork by removing 2 phillips head screws. 0:26 2 3/16" Phillips Screwdriver Reass20.JPG
6 Remove the front wheel assembly from the hole at the front of the frame. 0:05 1 None Reass19.JPG
7 Detach the front axle to the front fork by removing 4 phillips head screws and the left and right front wheel retainers. 1:00 2 3/16" Phillips Screwdriver 7dis.jpg
8 Remove the front wheel axle and 2 front wheel spacers. 0:10 1 None 8dis.JPG
9 Detach 2 front wheel covers to the front wheel by removing 6 phillips head screws. 1:20 2 3/16" Phillips Screwdriver 9dis.JPG
10 Detach the top and bottom frame braces from the front of the frame, removing 2 phillips head screws from each. 1:00 2 3/16" Phillips Screwdriver 10dis.jpg
11 Remove the hub cap, .437 retainer (using the needle nose pliers), rear wheel cover, left wheel, brushing .437 long black, washer, and other brushing .437 long black from the left side of the rear axle in that order. 4:00 3 - Not Meant to be Disassembled Needle Nose Pliers Reass14.JPG
12 Remove the hub cap, .437 retainer (using the needle nose pliers), rear wheel cover, right wheel, brushing .437 long black and the wheel driver 10 RIB from the right side of the rear axle in that order. 4:00 3 - Not Meant to be Disassembled Needle Nose Pliers Reass13.png
13 Remove the rear axle from the back part of the frame. 0:10 1 None 13dis.JPG
14 Detach the fender by removing 8 phillips head screws, one of which holds the cable that connects to the battery in place. 1:50 2 3/16" Phillips Screwdriver 14dis.jpg
15 By removing 6 phillips head screws, detach the left and right frame. 1:30 2 3/16" Phillips Screwdriver 15dis.JPG
16 By removing 2 phillips head screws, detach the console panel from the left and right frame and detach the console panel and its bottom piece by removing another 2 phillips head screws. 1:00 2 3/16" Phillips Screwdriver 16dis.jpg
17 Detach the left and right engines from their corresponding frames by removing 4 phillips head screws from the left and 3 phillips head screws from the right. 2:00 2 3/16" Phillips Screwdriver 17dis.JPG
18 Remove the phillips head screw holding the wiring to the right frame. 0:10 2 3/16" Phillips Screwdriver 18dis.JPG
19 Remove the motor clamp holding the motor-gearbox assembly in place by unscrewing 2 phillips head screws and take out the brushing .437 long black which is placed in the frame, behind where the motor-gearbox assembly was. 0:30 2 3/16" Phillips Screwdriver 19dis.JPG
20 Detach the pinion from the gearbox by removing 2 slotted head screws. 0:30 2 3/16" Slotted Screwdriver 20dis.jpg
21 Detach the 2 sides of the gearbox by removing 4 phillips head screws. 0:50 2 3/16" Phillips Screwdriver 21dis.jpg
22 Remove the 3 gears within the gearbox. 0:10 1 None 22dis.JPG
23 Remove the footboard assembly from the right frame by using force and possibly a knife to cut the sides a little. 1:00 3 - Not Meant to be Disassembled Knife 23dis.jpg
24 Remove the flat head slotted screw to detach the footswitch from the footboard assembly. 0:10 2 3/16" Slotted Screwdriver 24dis.jpg

To watch a video of the disassembly of the product follow theses links Disassembly Part 1, Disassembly Part 2, Disassembly Part 3

Ease of Disassembly Scale

  1. The piece is intended to be disassembled, disassembly can be done using common tools, and there is little effort required.
  2. Can be taken apart with non-specialized tools, and only average effort is required.
  3. Not intended to be disassembled or is tamper resistant, must be taken apart using uncommon tools, and requires a lot of effort.


Challenges with Disassembly

There were very few challenges with the disassembly of the product. The only real challenges were the disassembly of the .437 Retainer, the footboard assembly, and the gearbox.

Subsystem

The Power Wheels Harley Davidson© RockerTM can be divided into three subsystems. The first subsystem is the system which forms the physical structure of the product. The second subsystem is the system that helps in maneuvering and moving the system. The third subsystem is the system, which provides energy for the product to move. These three subsystems are connected to drive the whole system. The first subsystem, which is the frame or structure of the product, is connected to the second subsystem; which is the handlebar, fork, front wheel and the rear wheels, which help in the maneuvering of the product. The third subsystem, which consists of the battery, motor, gearbox, footswitch and forward and backward switches, is connected to the second subsystem which helps in moving the wheels and the whole system when human effort is applied to the footswitch and the forward and backward switch.

Connection:

Physical
The first subsystem that forms the structure of the product is connected using metal screws (#8 x 3⁄4" Screw – 10). This subsystem consists of the right frame, left frame and the rear fender.
The second subsystem consists of the handlebar, fork and front wheel. The second subsystem is connected to the first subsystem by sliding the fork into the slot provided between the right and left frame. The front wheel is connected to the fork using a metal axle. The handlebar is connected to the fork using the handle bar clamp and screws. The rear wheels are connected to the frames by sliding the rear axle into the right and left frames. The wheels are held in place using .437 retainers, which are held in place with an interference fit with the axle.
The third system consists of the battery, motor, footswitch, control switches, gearbox assembly and the wheel driver. The switches are connected to the battery and the motor using the wires. The motor is connected to the rear wheels via the gearbox and wheel driver, which help rotates the rear wheel assembly. The wires are held to the frame using plastic clamps.
Figure 1: Motor, battery, pedal and forward-backward switch connected with the electric current flowing through the wires signally.
Signal
The systems are connected via human and electric signals. The user sends directional signals into the handlebars to steer the product. The user also inputs a force on the footswitch and control switches which then send an electric signal to the motor telling it to rotate the tires either forwards or backwards.
Energy
The stored chemical energy in the battery converts to electrical energy and transfers to the motor when the footswitch is pressed down to complete the circuit. The motor converts the electrical energy into rotational kinetic energy which is then transferred into the rear wheels via the gearbox and wheel driver. Then the rotational kinetic energy is converted into translational kinetic which moves the entire product.

Arrangement and Placement

The product’s subsystems are arranged to increase the vehicle’s performance, comfort and the safety. The subsystems are also arranged in a manner that imitates a real Harley Davidson Motorcycle. Most of the subsystems in the product are simple connections which technically could allow them to be adjacent to each other. The only subsystems that cannot be placed directly next to each other are the handlebar assembly, which is used to steer, and the rear wheel assembly, which moves the toy, but only because doing so would cause the toy to cease function. Certain specific subsystems are arranged in a way that protects them from being tampered with or getting damaged such as the inner wire and motor.

Comfort:

  • The pedal which is placed under the right foot to provide easy access to activates the motor which in turn moves the gears in the gear box.
  • The forward-reverse switch is placed within the user’s reach to facilitate the driving functions.

Safety:

  • The motor and the gear box are placed together with the rear axle to generate rotational energy to move the rear wheels. This subsystem is hidden inside the frame of the toy to prevent tampering and injuries.
  • The battery is placed under the seat in order to allow easy access while providing a barrier from the intended user (a child).

Influences and Concerns:

Global
Standards for safety vary from country to country. As the law varies in different countries, the connections are standardized for usage based on the standards of the country the product is being sold in. The product is meant to be used in areas where the ground is flat and preferably paved, making it unsuitable to be sold in mountainous regions.
Societal
Different societies adapt the same pattern of connections, but vary in the different tools and their sizes used for connecting them.
Economic
The cost to produce the materials used connects the subsystems. The product's subsystems are mostly connected to each other using metal screws and plastic. Because plastics are produced using petroleum, the cost to produce the plastic components of the product varies based on oil prices. The price of the metal components such as the axle or the wires varies on with the price to produce the various metals.
Environmental
The plug and socket clamps for the wires along with the body and wheels are made of plastic and pose an environmental concern because of the materials used to produce plastic. In order to produce plastic petroleum (which is a non-renewable resource) is consumed. Fortunately, most of the plastic components of the product can be recycled, and the metal components can melted down and used in other products.
Performance
The area where the wires connect and where the motor and gearbox are placed as well as other parts of the product effects the performance. In order to maximize that, the product must have the parts placed in certain places or connected in certain ways.

Main Page

To navigate back to the main page click Group 25 - Harley-Davidson® Rocker™ Power Wheels