View a sample movie of the robots in ACTION!
Contest Date: Thursday June 9th 2005, 8:00am-11:00am
Location: Main Gym in-between Revelle and Muir
Building 263 is location C9 on the Campus Map
Public is Invited
Kit Part List and Motor CAD Models
Inventor Model - Download the Inventor model here!
Contest Description
Hoppers, Part Feeders, and other Material Handling devices are critical components of automation:
Vibratory Feeder Built by MAE156 Students
The Spring 2005 MAE3 contest is inspired by these devices, and each team of students will build a materials handling robot that will transport balls from a set of troughs to a depositing bin. The contest table has an upper trough that will be loaded with orange balls and a lower trough that will be loaded with white balls. A vibrator will shake the upper trough creating small ball motion.
Machines start on opposite sides of the troughs, as shown by “Start A” and “Start B” positions in the figure above. There is a chute between the upper and lower trough as shown below. The chutes open only towards the starting positions.
There is an arched base on the upper trough, tending to move balls away from the middle, as shown below:
There are bins on each end of the table (not currently shown in figures). The object of the contest is to collect the balls from the troughs and bring them back to the bin on the starting side of the table. Scoring is as follows:
One point for every white ball placed inside your bin.
Two points for orange ball placed inside your bin.
In the event of a point tie, the number of points attributed to orange balls will be the tie breaker.
Each MAE3 design team will build a robot that will compete head-to-head on the contest table. The robots will be arbitrarily assigned to start in either the right or left starting platforms. The starting size of each machine is limited to a cube of 12”x12”x12” and must fit unconstrained (i.e. not touching the sides) of the test cube. The airflow will be started prior to the beginning of the contest.
Each team will receive points for balls placed into their bin during a 60 seconds playing period. The scoring does not differentiate which side of the table the balls started from, so theoretically one could gain points from balls starting on either side of the table, but read the detailed rules below carefully to ensure compliance! There will be three playing fields built to accommodate all students in the class, and manufacturing tolerances will results in small variations between the contest tables. It is the design teams responsibility to develop a robot that will work on all contest tables.
Each team will build a machine using the kit parts described below to perform the task. The kit will include 5 DC motors (2 will have gearboxes) and one solenoid. Electrical power will be provided from a power supply with a maximum of 5VDC output. The power will be controlled by the following switches:
· Two 5 Volts DC switches
· Two variable voltage switches (note; maximum current output is less in these switches!)
Each switch is Double Pole Double Throw (DPDT) switches, which can operate a DC motor in either direction. Note the kit contains five DC motors and one solenoid, but only four user controlled switches. More than one electrical device can be connected to a single switch, but the voltage may drop if a large current draw is placed on the power supply. Use of motors, solenoids, and switches will be covered in lecture and is described in the Mechanical Device textbook.
Contest Event Description
The contest will be held during the MAE finals period and will be open to the public. The contest will be held in a single elimination fashion (like a tennis tournament). During the lab period of the last week of classes, each section will hold a section-wide contest. The results of this contest will be used to seed the placement of the final contest. Thus teams that perform better during their section contest will have statistically easier contests in the early rounds. Since the number of teams in the class will not be exactly a power of 2, the higher seeded teams may get a "buy" during the first round. If necessary random numbers will be used to ensure a proper contest pyramid.
Performance in the contest depends on numerous factors that do not relate to engineering quality of the robot, including driving skill and luck! The grade for the project will not be adversely affected by poor performance in the contest, but will be based upon:
· Ability to achieve to design objectives selected by the team, and performance of the machine without an opponent.
· Effective communication of the design (orally and in the web report).
· Documentation of the design process and justification of decisions made.
· Analysis of machine performance.
· Following good design practices.
A trophy will be presented to each member of the winning teams, and a number of machines will be selected for display in the Design Studio and MAE Department. Team members must work out among themselves who will keep the final machine (after their display period). All members will make a web page describing their machine (including video), which they can cherish forever.
Each team must return the geared motors, since their price is not included in the course fee. Anyone wishing to keep their complete robot can purchase replacement geared motors, and turn them in to keep their robot.
Contest Rules
Energy Sources: The energy used by the devices in the competition must come solely from:
Potential energy derived through a change in altitude of the center of gravity of the machine;
Potential energy achieved by the deformation of the Springs provided by the Kit
Electrical energy derived through the umbilical during the 60 seconds when the power supply is energized.
Size: At the start of each competition, every part of the machine must fit, unconstrained, inside the 12”x12”x12” starting area, whose base is completely aligned with the marked starting area on the playing field.
Umbilical Cables: The electrical connections will made to a single umbilical cord hung from above the table; one on each side of the table. The umbilical cord cannot be touched during the contest, and there will be some drag from the cable. Each machine must be designed to overcome this drag if necessary for motion of the machine.
Detailed Rules
1. Judges and/or instructors will disqualify any device that appears to be a safety hazard.
2. Any machine that has flying parts must notify opponents, and all contestants must wear safety glasses during the machine operation.
3. If a projectile is used, for reasons of safety, it must have a frontal area greater than 2 inch squared.
4. Contestants will randomly be assigned to start on either side of the playing field.
5. A maximum set-up time of 2 minutes will be allowed at the contest table.
6. A maximum of 1 minute will be allowed for removal of all parts of each machine after each contest.
7. Operators may interact with their machine during a contest only through normal operation of the switch boxes (for example you cannot touch the machine with one's hands during operation).
8. It is allowable to adjust the configuration of the machine between contests; for example adjusting the configuration to the side of the playing field the machine starts on.
9. Each machine can only interact with the surface of the playing field and objects on the playing field.
10. The judges will wait until all the playing pieces have stopped moving before determining the winner.
11. A ball will be considered inside the bin if it is completely inside the bin.
12. Points will be awarded based upon the final location of the playing pieces, regardless of which machine moved them.
13. A playing piece will be declared out-of-bounds if it is off the playing field.
14. The tie breaker must be on the playing field for it to count.
15. Damaging the playing field or the control boxes may result in disqualification.
16. Purposefully using the electrical cables for any purpose other than transmitting electrical is not allowed.
17. Gaining traction by use of adhesives, or by abrading or breaking the surface of the playing field is not allowed.
18. A machine may not contaminate with lubricant or other substance the playing field, an opponent's machine, or the playing field (internal lubrication of a machine is permissible).
19. Kit materials may not be changed chemically. DC Motors may not be rewound.
20. The paper that is attached to the acrylic in the kit cannot be used as a separate element in the machine. If any piece of paper is detached (even partially) from the acrylic it must be discarded.
21. The insulation must remain on the electrical wire in the kit except where the wire end is attached to another component, and there up to 0.5” of insulating can be removed.
22. The clear acrylic 0.25 thick is for testing. If you include any of this acrylic in your final machine, you must remove an equivalent amount of colored acrylic that was used in making the part.
23. Spare parts are available on a limited basis. Students should go to the tutors of their section to receive replacements for parts broken. Student can purchase replacement acrylic from upper campus machine shop or off campus (see Chris Cassidy for sources)
24. Machines may be designed to interact. However, it is not in the spirit of the competition to intentionally damage another machine and no part of the kit may be used in a manner that is intended to cause harm. Any device which is designed to chop, break, or penetrate another machine will not be allowed to compete. If you think your machine may be at risk for violating this rule, ask early before you build it!
25. Machine advertisements and decorations must be of the nature that it does not offend any other students or audience participants (use common sense!).
26. All rulings of the judges will be final.
Any modifications or clarifications to the rules or kits will be posted on the class web page.
Clarification to Contest Rules
Kit Parts Rules
Each machine must be constructed solely from materials provided in the Kit listed below, i.e. one cannot substitute a 12"x16" piece of acrylic with a 6"x32" piece.
If a part of the kit is damaged it can be replaced from the scrap pile, as long as the design team can show that they could completely rebuild their machine solely from the kit.
In addition to the kit parts listed in the table, the following items may be included in the machine:
· Nuts, bolts, and washers included in the Design Studio bin. These include bolts from size 2 to size 10, and metric screws for mounting the motors.
Only take nuts and bolts from the bin as you need them, and search through the spare bolt bin before taking more (we went through $1,500 in fasteners last year!)
· Fasteners can be used only for fastening purposes, and thus must fasten at least two other parts together.
· Adhesives; including hot melt glue, and acrylic adhesive.
· Tape used ONLY for electrical insulation
· Lubricants used only to reduce friction.
· Nonfunctional decorations.
Replacement Material Policy
We have some extra material that can be used for experimentation. This material will be made available in the lab scrap bins. In addition each section tutor has access to a limited amount of replacement material for their section. If you need replacement parts, contact your tutor. Some replacement of "mistakes" made to kit parts will be available, but supplies are limited, and replacement is not guaranteed.
Kit Part List and Motor CAD Models
Frequently Asked Questions (FAQ)