Log December 20, 2011

This week, my group and I have been diligently working on drawings and paper work to submit for our developmental work.

Plan of Procedures

Plan of Procedures: Tank Assembly

1)      Place 10’x10’x1” piece of pine wood on the floor (if there is no 10’x10’ board, use 2 10’x5’ boards next to each other)

2)      Using 3”wood screws and power drill kit, secure 3’x10’x1’ by placing one wood screw through the bottom of the 10’x10’ board, once every 5 inches so that the walls are 3’ tall.

3)      Secure another 3’x10’x1’ on the opposite end of the 10’x10’ square using the same procedure

4)      Cut 1” off long ways off both sides of the two 3’x10’x1” boards

5)      Attach the two boards on opposite ends of the base from the bottom of the 10’x10’ board with 3” screws placed once every 5 inches using the power drill kit so that the walls are 3’ tall

6)      Using 3’ screws, starting at the top of the 3’ walls, attach the corners together with one screw every 5 inches from the outside panel of each wall (shown below).

7)      Cut 1” off both ends off two 3’x10’x1” boards long ways, and attach them to the base, directly in front of the longer walls, parallel to them. Screw them to the base using the same procedures as previously done

8)      Cut 2” off each end of two 3’x10’x1” boards long ways and attach them to the base, directly in front of the shorter walls, parallel to them. Screw them to the base using the same procedures previously used.

9)      Attach Tico hangers to the outside corners of the tank as structural support.

Plan of Procedures: Liner Assembly

1)      Cut 4 15’ strips of 5’ wide liner

2)      Using glue on both ends, attach the liner strips to each other long ways with 30% overlap on each end (i.e. 4 inches for every foot)

3)      Place liner in the tank

4)      Using a staple gun, attach the liner to the tank along the outside upper rim with 2” spacing between staples

5)      Fill liner slowly with water, caulking any leaks along the way

Materials List

• 2 gallons of HH-69 Vinyl Cement
• Pool Liner
• 1 10’x10’x1” Piece of Pine Wood
• 8 3’x10’x1” pieces of pine wood
• 200 count box of 3” wood screws
• 4 tico hangers at least 1 ft in height
•  Power drill kit
• Caulk
• Caulk Gun
• Staple gun
• Staples
• 100 ft + of ½ diameter rope
• Saw
• Clamps
• Staple Gun
• Staples

Orthographic Front View

Orthographic Side View

Orthographic Top View

Exploded View

Isometric

Log December 9, 2011

With further construction of the bot being completed, there were only 2 remaining challenges to create apparatuses for. Fortunately for us, one ancillary piece would accomplish both tasks. As can be seen in the front left of the kit, the hook has been assembled for the boat tow as well as the sinking of an enemy vessel and was added this week. The camera was also added in the center of the vex kit to aid in the aiming of the slingshot. 

Log December 7, 2011

After much work sith the VEX kit, there was a continuation of construction today and an assessment of flaws associated with the original design. After much deliberation, the apparatus for dropping the buoy was shortened from the square design to the triangle design. Also, there were structural supports added to the central slingshot.

Log December 4, 2011

This week, after the generous donation of one Mrs. McD, we utilized plastic baggies and further organized our vex kit into its component parts, labeling each bag along the way. There was also a continuation of construction this week. 

Log November 28, 2011

This week, my group and I began to organize the VEX robotics kit into specific systems and began construction of the hull of the aquatic vehicle. The primary focus was to understand the pieces we were working with and understand the limitations and possibilities for the vex robotics kit.

Log November 23, 2011

This week, I worked to modify my model, so that it would meet the class standards. I also worked to modify my calendar to show my due dates for this marking period, as well as to help me manage my time.

Log November 15, 2011

Today in class, I worked to improve my mentor contacts, and did final editing to my progress poster. Yesterday I completed my raw Formal progress update poster, which as previously stated, I edited today.

Update Poster

Mentor Contacts

Lou (Hobby Masters Employee)
2 Hour Contact

Items learned
-There is a difference between motors and Servos
-A higher voltage battery will increase our power output as well as operational time
-our Reciever also works as a transmitter and power modulator

Mentor Contacts

RECIEVED- Joe Helble

Robert,

Thanks for the update and the link to your blog.  It’s well put together, and gives a good sense of the project and design process.  I have just a couple of questions and suggestions for you at this point in time.

(1) you did a nice job explaining the decision matrices as a means to guide your approach to each challenge.  I noticed, however, that for a few of them, the differences among some of the leading choices were fairly small (i.e. 1 point).   Since the numerical score associated with each criterion is fairly subjective, are there cases where you can explore perhaps two different options briefly before making a final design decision?

(2) you used the decision matrices to make a choice on the best way to meet each individual challenge, but my understanding is that each one of these “solutions” needs to be mounted on the vehicle at the same time.  (i.e., you don’t take oof the upward hook to mount the slide when moving from challenge 3 to 4, correct?).   If that is the case, have you considered a fifth matrix that would enable you to evaluate the merits of integrating the different components onto the core vehicle?   I can’t tell the size of your vehicle from the information I have seen, and if you have a large vehicle (and small claw, slide, etc.), then this isn’t an issue.   But if you need to worry about balancing the load, and making sure each “appendage” is free from interference from the other “appendages” during operation, an additional matrix that considers issues of integration could be helpful in making design choices.

(3) the relationship between the problem statement describing sand dune erosion and the amphibious needs of the vehicle wasn’t clear to me.  It may be in one of your earlier posts, but I didn’t get a good sense of this from the pages I read.

(4) in the Rationale Report, the sentence just above the first table isn’t complete.  I suspect some text was cut off when you added the table.

Let me know if you have any questions.  Overall, it seems you’ve gotten off to a good start on this.

Joe

RECEIVED- Joe Walsh

Rob,

I quickly looked over your project and found it very easy to follow and it was very informative.

When I have more time (hopefully tomorrow) I will look at your proposal closer.

Have a good day.

Joe

RECIEVED- Joe Walsh

Rob,

Sorry I haven’t gotten back to you until now.

One quick question is your project based on keeping the dunes intact?  And if it is, what exactly are the aquatic challenges since the dunes are mainly upland?

Joe

Mentor Contacts

RECIEVED

Robert,

Thanks for the update and the link to your blog.  It’s well put together, and gives a good sense of the project and design process.  I have just a couple of questions and suggestions for you at this point in time.

(1) you did a nice job explaining the decision matrices as a means to guide your approach to each challenge.  I noticed, however, that for a few of them, the differences among some of the leading choices were fairly small (i.e. 1 point).   Since the numerical score associated with each criterion is fairly subjective, are there cases where you can explore perhaps two different options briefly before making a final design decision?

(2) you used the decision matrices to make a choice on the best way to meet each individual challenge, but my understanding is that each one of these “solutions” needs to be mounted on the vehicle at the same time.  (i.e., you don’t take oof the upward hook to mount the slide when moving from challenge 3 to 4, correct?).   If that is the case, have you considered a fifth matrix that would enable you to evaluate the merits of integrating the different components onto the core vehicle?   I can’t tell the size of your vehicle from the information I have seen, and if you have a large vehicle (and small claw, slide, etc.), then this isn’t an issue.   But if you need to worry about balancing the load, and making sure each “appendage” is free from interference from the other “appendages” during operation, an additional matrix that considers issues of integration could be helpful in making design choices.

(3) the relationship between the problem statement describing sand dune erosion and the amphibious needs of the vehicle wasn’t clear to me.  It may be in one of your earlier posts, but I didn’t get a good sense of this from the pages I read.

(4) in the Rationale Report, the sentence just above the first table isn’t complete.  I suspect some text was cut off when you added the table.

Let me know if you have any questions.  Overall, it seems you’ve gotten off to a good start on this.

Joe

Mentor Contacts

Email Message:

SENT

 

To My Mentors:

    Over the past month or so, I have been working on the paperwork accompanying my project, along with my other studies. Most of this paperwork is done and I am going to be giving formal project update presentations next week, and a few weeks after to my class. You may see the work I've been doing at the following link: http://sharkeyvex.blogspot.com/. I would love to hear your opinions on everything from formatting, to ease of use, to content, etc. I look forward to hearing from you. if you have any questions, please do not hesitate to ask.

-Robert Sharkey 

Final Solutions

Challenge 1: Signaling an Aircraft

            For the first challenge we have chosen solution number two, the use of a slingshot to propel a projective into a hoop. The device will operate on a single 3 wire servo. The projectile will be put into motion by the release of two elastic bands which were kept under tension until the unit needs to be used. The single servo will operate a blade which will cut the string, holding the elastic under tension

            The base of the structure will be one beam, 12 inches long, mounted onto the hull of the vessel at a 30 degree angle. Two 8 inch upright struts mounted perpendicularly will hold the beam in between them, six inches from the deck of the vessel. The elastic bands are attached at the top of the 8 inch struts, two inches above where they hold the beam. At the other end of the 12 inch beam where it meets the deck, a two inch strut will be mounted perpendicularly to the beam. From this strut, a 2 inch piece of twine will hold the elastic back 10 inches, parallel to the beam. The ball will be placed in front of the elastic, sitting on the beam.

            Next to this system will be the cutting mechanism. One blade of a scissor will sit underneath the string, perpendicular to it. The drive shaft of a 3 wire servo will move another blade in a 40 degree arc downward, meeting the fixed blade under the twine. This action will cut the string and release the tension in the elastic, projecting the ball from the vessel.

            This solution was chosen based primarily on how quickly it could accomplish its task and how simple the operation was. It consists of cutting only one string, and that will propel a projectile at a very quick speed. As opposed to the other solutions with design stood above in nearly every facet of selection.

Challenge 2 and 3: Towing a Stranded Vessel and Sinking an Enemy Vessel

            For challenge 2 we selected a hook sweeping downward, and for challenge3 we selected a hook sweeping upward. To reduce material use and motor capacity we have combined both of these actions into one ancillary unit. The hook will move both up and down, spanning a total of 110 degrees.

            The hook will be mounted horizontally on the side of the vessel with the 3 wire servo sitting on the hull. It will be capable of extending 80 degrees upward and 30 degrees below its parallel mark. This will ensure the hook can reach over the transom of the stranded vessel. It will also allow the hook to dip into the water and extend beneath the enemy vessel before it retracts upward in order to capsize it.

            The hook’s arm will be 8 inches long. The drive shaft of the servo will connect to the arm 2 inches from the end. A weight will be placed on the shorter side to help the hook rotate. On the end of the 6 inch side a two strut will be attached perpendicularly downward. This will help the hook anchor itself to the stranded vessel. On the opposite side facing up a .5 inch point will help it puncture when it is extended upward into the underside of the enemy vessel.

            This hook was chosen for both of these solutions because of their ability to be combined into one, the simplicity of their actions, and their chance of success. Neither one of these tasks is easy to accomplish. Using one unit for two solutions gives us an extra motor space for the controls of the vessel itself.

 

Challenge 4: Floating a Buoy

            For challenge 4 we selected the third solution, the use of a motor operated slide to drop the buoy off the side of the vessel. The slide will be titled down at an angle of 45 degrees. The buoy will travel down a grooved path in the slide and into the water. Before the buoy needs to be dropped, it will rest at an angle of 155 degrees upward to prevent any chance of the buoy sliding without the chute going down.

            The slide itself will be 8 inches long. The servo which controls the slides tilt will be attached 2 inches from the back, allowing the slide to tilt upwards and have the buoy rest against a fixed back piece mounted perpendicularly to the end of the chute. The slide will be on the stern of the vessel, mounted to the transom, amidships. The buoy will be dropped over the starboard bulkhead  

            We chose this solution because it was the simplest, and most material effective. The others would have been too complicated or used too many motor units. The slide also has a very high change of success as there are no complex moving parts, only one rotating servo.

Log November 7, 2011

Today, in class, we continued with formal presentations. The wave tank groups as well as the website portion of the herbarium group presented today. Fantastic job guys!

Brainstorming

Brainstorming

• Beginning of the year consulting
• Group Consulting
• “jotted” notes
• Scribbled drawings on papers

Log October 28, 2011

This week we went through presentations as a class and my group and I finalized our alternate solutions, with drawings for each one and paragraphs describing them all.

Alternate Solutions

Alternate Solutions:
Every individual aquatic challenge necessitates the design and construction of a unit capable of performing the given task. Below are four different variations of the units designed to complete each challenge.

Challenge 1: Placing a ping-pong ball through a hoop

1. Catapult- The catapult will use a tension release arm pre-loaded manually. A 3-wire servo will release the arm using a standard drive shaft to straight gear system. The arm itself will be constructed from the booster kit with a plastic cup fixed to the end. A structure in front of the arm will limit its range of motion to 70 degrees, also causing the arm to return back to the resting position after firing.
2. Slingshot- The slingshot will consist of two upright structures mounted directly to the hull. Connecting them near their apex will be an elastic string. When pulled back this string will be loaded onto the same mechanism used on the catapult design. A servo will release the tension in the elastic firing the projectile.                                                    
3. Pinball- The pinball mechanism will work like the firing mechanism in a pinball machine. A spring will be attached to a contact surface. This system will be placed into a tube with a release mechanism powered by a 3-wire servo. Once released, the contact surface will strike the projectile and fire it down an exposed pathway approximately 8 inches long. 
4. Telescoping claw- The claw will hold the projectile until it is ready to be released. This action will be controlled by a 3-wire servo. The arm to which the claw is attached will extend under the power of a 269 motor. The drive shaft will rotate a gear which will have contact with fixed gears along the arm. 

Challenge 2: Towing a Stranded Vessel

1. Hook- The hook will be a single jointed with a 3-Wire servo at the base where it is mounted to the hull. The arm of the hook will extend approximately 12 inches with a 3 inch offshoot connected perpendicularly downward at the end. This offshoot will have an adhesive contact surface on its inner side to grip the inside of the hull of the stranded vessel
2. Magnets- The magnet solution will simply be an electromagnet mounted to the hull of the vessel. A 3-wire servo will control the circuit from the auxiliary battery in order to shut the magnet off when the stranded vessel needs to be released, and before the vessel needs to be towed. A piece of magnetic material must be mounted on the stranded vessel prior to the rescue attempt. 
3. Telescoping rod- On the end of an arm an adhesive contact pad will be applied. The arm will be approximately 12 inches long, and controlled by one 269 motor. A gear on the end of the motor drive shaft will rotate and move the fixed teeth on the arm. When retracting, two upright structures will be mounted directly to the hull of the vessel. The arm will be able to retract past these two structures but the vessel being towed will be disconnected. 
4. Pincers- There will be one fixed arm with a contact pad on the inner surface. The other arm will be fixed onto a structure running perpendicular to the arms. The mobile arm will move horizontally across this structure under the power of one 269 motor. The gear ratio will be adjusted to ensure slow but steady movement on the arm.                       

Challenge 3: Sinking an Enemy Vessel

1. Downward hook- The hook will be mounted onto the vessel and pivot from the hull of the vessel. The rotation will be downward 110 degrees in an attempt to capsize the vessel. This motion will be controlled by one 3-wire servo. The arm will be approximately 12 inches long and be constructed form the booster kit.                                               
2. Hole puncher- The hole puncher will be a weighted rod approximately 0.5" in diameter. This rod will be housed inside of a tube with a loaded spring behind it. The spring tension will be release by the operation of a 3-wire servo controlled gear slide system, similar to the one used in the pinball solution for challenge 1.                                            
3. Upward hook- The hook will be mounded onto the side of the vessel. It will dip into the water prior to its operation and them rotated upward under the power of a 3-wire servo in an attempt to capsize the enemy vessel. The servo will be at the base of the hook, where it mounts to the hull. The arm will be approximately 12 inches long.                        
4. Splitter- The splitter will be single jointed mounted at the hull. Two upward struts and an elastic band will provide tension for the splitter to release upward and down in a full 180 degree arc. A 3-wire servo tension release mechanism similar to the hole puncher's mechanism will release the arm of the splitter. The arm will be approximately 12 inches long and have a weighted blade at the end. The blade will attempt to split the enemy vessel, destroying it. 

Challenge 4: Floating a Buoy

1. Magnet- The magnet releasing system will will operated based on a connection controlled by a 3-wire servo between an electromagnet and its ancillary battery. The magnet will attract an opposing magnet on the buoy itself. When the connection is broken the buoy will drop off the side of the vessel.  
2. Rotating claw- The claw will be mounted on an arm approximately 4 inches long. The arm will be mounted directly to the deck of the vessel and rotate under the power of a 3-wire servo. The claw action itself will be under the power of an additional 3-wire servo. When the claw releases, the buoy will be dropped into the water. The arm can then rescind the claw back to its place above the vessel. 
3. Slide- The buoy will be placed before the mission at the end of a platform approximately 8" long and 4" wide. One 269 motor with a gear and drive shaft will move a piling up and raise the side of the platform with the buoy. The piling will extend to approximately 6". The buoy will then slide down the platform and into the water. The 269 motor will reverse, and return the piling, leveling the platform.
4. Cutting a tow string- The buoy will be towed behind the vessel for the entire mission until the time to float it comes. At this time, a 3-wire servo will rotate a drive shaft with one 1" gear on the end. This will turn another, smaller gear next to it, which is attached to the action of a pair of scissors. These scissors will cut the string, releasing the buoy.

The Rationale Report

Rationale Report

For each of our four aquatic challenges we created four possible solutions. Each one of these solutions is a different design of an auxiliary unit attachable to the main hull which is capable of completing the given task. To decide which of the four alternate solutions is to be constructed and implemented we created a design matrix specifically for each unit. The criteria are simplicity, availability of materials, practicality, length of operation and accuracy of operation. Each alternative solution was assigned value from one to five for their performance in each criterion. The totals are given at the bottom of each spread sheet.

Simplicity deals with how many moving parts the solution has, and how many parts are involved. This can include motors and joint units. Availability of materials takes into account the scarcity of the the resources in the vex robotics kit, and how many of those resources this solution would use. This also deals with any materials not provided, and how difficult obtaining those would be. Practicality is the level of physcial possibility of the solution. In other words, its how easily the design would be to construct. The length of the operation is how long the unit takes to complete the challenge. The accuracy of the operation is the chance of success for the unit.

Challenge 1: Placing a Ping Pong Ball Through a Hoop

Criteria	Solution 1: Catapult	Solution 2: Slingshot	Solution : Pinball	Solution 3: Extending Claw
Simplicity	3	4	4	2
Availability of Materials	4	3	3	2
Practicality	2	3	2	4
Length of Operation	5	5	4	2
Accuracy of Operation	2	3	4	5
Total	16	18	17	15

Challenge 2: Towing a Stranded Vessel

Criteria	Solution 1: Hook	Solution 2: Magnets	Solution 3: Telescope Adhesive	Pincers
Simplicity	4	2	1	2
Availability of Materials	3	2	2	3
Practicality	4	3	2	3
Length of Operation	2	5	2	3
Accuracy of Operation	4	3	4	4
Total	17	15	11	15

Challenge 3: Sinking an Enemy Vessel

Criteria	Solution 1: Hook (downward)	Solution 2: Hole Puncher	Solution 3: Hook (upward)	Solution 4: Axe
Simplicity	5	3	4	5
Availability of Materials	3	2	5	1
Practicality	3	3	4	2
Length of Operation	2	5	2	5
Accuracy of Operation	4	4	4	3
Total	17	17	19	16

Challenge 4: Floating a Buoy

Criteria	Solution 1: Magnet Release	Solution 2: Rotating Claw	Solution 3: Slide	Solution 4: Tow and Cut
Simplicity	2	1	4	3
Availablity of Materials	1	3	4	1
Practicality	4	3	5	2
Length of Operation	4	2	3	3
Accuracy of Operation	5	2	5	3
Total	16	11	21	12

With these matrices the selection of each unit is significantly expedited. The design of the unit with the highest total score will be selected and committed to construction and integration.  For challenge one, solution one, the slingshot was selected with a score of 18. The hook was selected for challenge two with a score of 17, the upward rotating hook for challenge three with a score of 19, and the slide for challenge four with a score of 21. These four units will be more intricately designed and drawn out and finally put into construction. The hull will be based around accommodating these ancillaries.