2004 DarkSabre MPC

Articles in this series

The following is a list of pages pertaining to Mission Possible for Division C. Some of these pages may contain outdated information.

• Main Article
• Documented Devices
  • 2004 DarkSabre MPC
  • 2005 DarkSabre MPC
    • A guide to programming with Lego Mindstorms and NXT
  • 2010 Paradox21 MPC
  • 2018 Davecutting MPC
  • 2018 FHC MPC
• Useful Components
  • Thermal Devices
  • Optical Devices
  • Mechanical Devices
  • Electrical Devices
  • Chemical Devices
• Year-Specific Information
  • 2018 Tasks
  • 2019 Tasks

2004 DarkSabre MPC

This is Dark Sabre's Energy Transfer List (ETL) from the 2004 National Tournament. Added on are two columns (Picture and Description) to help explain what is going on. The pictures here have been cropped significantly to help show exactly what is going on. Many more pictures are available on the gallery here.

Note that the rules for the ETL have changed every year and the below should not be considered an example for whatever the current rules are.

This machine was not nearly as successful as my entry in 2005. This is mostly my fault, rather than the machine's. At nationals, I was nervous and over-volted my laser, which broke it (goodbye starting transfer). I also forgot to uncap the sharpie that was supposed to draw a figure-8 on the post-it. I also misaligned the squirt gun and it got water on a judge :P. Nationals was in Juniata that year and it rained. A lot. My static detector, which was a little gimpy to start with, failed completely. Needless to say, I went into 2005 having learned some lessons about building machines and not screwing up from being nervous.

No.	Action	Ending Energy	Points	Bonus	Picture	Description
	Playing card drops through slot onto see-saw, raising light barrier	Mechanical
1	Laser shines through diffraction grating, breaking beam into primary, secondary, tertiary, etc dots	EMS	10	15		This setup was designed to satisfy a number of bonuses. The starting task was to drop a playing card into the machine. There was a bonus for using a mirror and also one for using the principle of diffraction. When the card dropped, it lifted a shield from in front of a laser, which then shined through a piece of diffraction grating and then one of the diffracted dots (not the primary laser path) shined on the light sensor.
	Some dots reflect off of a mirror	EMS		15
	A secondary dot hits Lego light sensor which signals RCX	Electrical
	[RCX triggers motor]
2	Motor turns Lego arm, hitting switch	Mechanical	10			Hard to see here, but it isn't really important. Just a motor hitting a microswitch.
3	Switch disconnects the electromagnet	Electrical	10
4	Electromagnet releases metal ball	Mechanical	10	15		Electromagnet (magnet wire from Radioshack wrapped around a nail using a drill) drops a ball bearing into the seesaw.
	Ball tips see-saw, raising permanent magnet	Mechanical
	Magnetic switch is triggered by movement of permanent magnet	Mechanical		15		Cow magnet on a window security sensor (has a magnetic reed switch inside that toggles in the presence of a magnet). Bought it at Radioshack.
5	Magnetic switch completes circuit	Electrical	10
	Electricity passes from an audio source (radio) through a 1:1 transformer	Electrical		30		This is actually a picture from my 2005 MPC, but I used the same setup. Use of a transformer was a bonus. The little green box on the left is a 1:1 transformer. Lacking an AC signal in the Mission box, I used a weather radio, which provided a working alternative. The green Lego box housed the LED that the radio powed via the transformer. The transformer is from Radioshack.
	LED is lit	EMS
	Light from LED triggers a Lego light sensor, which signals RCX	Electrical
	[RCX triggers motor]
	Motor pushes trigger of the (non-flammable) air can, releasing pressurized air	Mechanical				The state bonus was for playing two consecuative, different notes on a harmonica. This massive rig held a compressed air can (for cleaning keyboards). I tried out a few brands until I found one that didn't use an ignitable propellant. The upper motor pressed in the trigger of the air can, which blew air through one note and tipped over the orange arm (right side) to cover a light sensor. This triggered the motor at the bottom, which switched the pneumatics to play a second note and then disengaged the air can.
	Air pushes arm over a light sensor [plays first harmonica note]	Mechanical
	Change in light triggers light sensor, which signals RCX	Electrical
	[RCX triggers motor]
	Motor turns and switches the air flow through a pneumatic switch	Mechanical
	Air pushes second arm over, rotating axle [second harmonica note plays]	Mechanical		50+50+15
	Change in position of arm's axle triggers rotation sensor, which signals RCX	Electrical
	[RCX triggers motor]
	Motor turns arm, hitting a switch	Mechanical
	Circuit is completed	Electrical
6	Nichrome wire increases in heat, lighting the candle	Thermal	10	15		The candle is actually not present here, but it was a tea-candle and rested between the two alligator clips, which held a piece of Nichrome wire that was wrapped around the wick.
7	Candle burns natural fiber	Chemical	10
8	Formerly suspended weight is dropped	Mechanical	10			There were two bonuses here, one for storing energy in a spring and one for releasing energy from a spring. Neither were allowed to be "spurs". The weight it shown hooked onto the hook from which it would usually be suspended with fishing line. You can see one of the alligator clips that held the Nichrome wire. When the weight was released, it fell down the tube and compressed a fairly powerful spring (storing energy in a spring). Underneath the spring was a momentary switch, which was in turn depressed by the spring. The spring then lifted the weight (releasing energy from a spring) and the switch at the bottom was released. This oscillation happened a few times. The switch at the bottom controlled a solenoid, which was pressing and releasing a touch sensor as the switch at the bottom of the tube was pressed and released. The RCX program counted the number of press/releases and would only trigger the next transfer after x cycles. This demonstrated that the spring's oscillation and sequential storage and release was vital to the operation of the machine.
	Switch is depressed by weight's weight	Mechanical
9	Circuit is completed	Electrical	10
10	Nichrome wire increases its heat, melting the fishing line	Thermal	10
	Weight is dropped, storing energy in the spring	Mechanical		30
	As the spring releases its energy by depressing the switch at the bottom of the tube, it lifts the weight	Mechanical		15
	This is repeated, pressing the switch and completing the circuit multiple times	Electrical
	Solenoid alternately depresses and releases touch sensor	Mechanical
	Touch sensor sends signals to RCX	Electrical
	[RCX triggers motor]
	Motor lowers the cathode into vinegar jar	Mechanical				The first part of the Chemical Battery bonus, the copper pipe was lowered into a vinegar jar to complete the battery. This was also where I manually adjusted time for how long the device would run. The higher up the pipe, which lowered very slowly, started, the longer the device ran.
11	Anode, cathode, and vinegar react	Chemical	10			A vast improvement over the 2003 Mission, I used an ice cube tray with copper and zinc metal strips. I believe each side was in series with itself and in parallel with the other side. Regardless, it generated enough current to power the LED featured below.
	Reaction produces voltage	Electrical		15
12	LED turns on, shining on light sensor	EMS	10			Low-current LED from Radioshack, housed in an enclosed Lego box.
	Light sensor signals RCX	Electrical
	[RCX triggers motors}
	Pen and paper drives move in coordinated motion to draw a figure eight	Mechanical		100		The National bonus that year was for drawing a figure-8 on a piece of paper. This was a two-axis drawing machine I built that I could attach a sharpie too. Just programmed it to draw the shape I wanted.
	Movement of the paper drive activates a touch sensor	Mechanical
	Touch sensor signals RCX	Electrical
	[RCX triggers motor}
	Motor spins PVC pipe against rabbit fur	Mechanical
	Static charge is built up via the mechanical transfer of electrons	Electrical
	The "Static Detector" detects change in static potential	Electrical		30		There was a bonus for using static. This rotated a PVC pipe against the "fur" of a fake mouse toy. Sorta visible is a resistor and a Field Effect Transistor, which acted as a rudimentary static detector. This triggered a low voltage LED.
	Circuit is alternately completed and broken by Detector	Electrical
	LED flashes on and off repeatedly	EMS
	Repeated change in light is sensed by Lego Light sensor	EMS
	Light sensor signals RCX	Electrical
	[RCX triggers motor]
	Motor turns, dumping Na2CO3 into jar	Mechanical				This is an example of chemical precipitation, which was a bonus that year. I kept the darker half of the solution, the ferric chloride, in the test tube (which had the light beam passing through it to the light sensor) so that it was demonstrable that it was not the color of the two components separately, but the actual precipitation reaction that triggered the next transfer. I got the ferric chloride from my chem teacher and the washing soda from the grocery store.
13	Na2CO3 reacts with FeCl3 to make a semi-opaque precipitate	Chemical	10	15
14	Precipitate blocks light source from light sensor	EMS	10
	Light sensor signals RCX	Electrical
	[RCX triggers motor]
	Motor dumps Ammonium Chloride pellets into water	Mechanical				For the "Decreasing heat" bonus I opted for a chemical reaction in 2004. The 2005 solution is much more elegant. This dumped the pellets from the one-shot cold-packs you can buy at the grocery into a bin of water, which had a temperature sensor in it. The chemical reaction made the water quite cold and triggered the next transfer.
15	Combination of substances results in a decrease in heat	Thermal	10	15		To speed the above reaction, I mounted the water bin on a rotating base, which swished back and forth rapidly, stirring the mixture.
	Decrease in heat is sensed by temperature sensor	Thermal
	Temperature sensor signals RCX	Electrical
	[RCX triggers motor]
	Motor turns, changing position of pneumatic switch	Mechanical
	Pneumatic piston pushes the trigger of a toy squirt gun	Mechanical
	Water is hydraulically forced out of the toy squirt gun, runs down a funnel, and lands on candle	Mechanical		15+15		The final task was to extinguish the candle that was lit earlier. There was another bonus for using a toy squirt fun in the machine. This did both: the pneumatic cylinder pressed the squirt gun's trigger and the water ran down the plexiglass, through the funnel, and onto the candle.
	Candle is extinguished by water	Thermal