exploded iso

Plan of Procedures

1.) Cut ¾” PVC piping into four 12” long pieces, four 9” long pieces, and four 8” long pieces

2.) Insert one 12” PVC pipe and one 8” PVC pipe into each 90 degree PVC elbow. There should be four elbows with an 8” and 12” pipe in each; similar to the item in the picture below.

3.) Now position the Tee connectors onto the 12” PVC pipe. Two should go onto each 12” PVC pipe, in ¾” from each end of the pipe. This can be scene in the figure below

4.) Now use the other four 90 degree elbows to connect these four pieces together. This can be scene in the figure below. There should now be two of these parts complete

5.) Next insert a 9” PVC pipe into each of the openings on all eight Tee connectors. This should connect the two parts you have and finish the structure.

6.) Now, connect one propeller to the left, upper 12” inch PVC pipe using screws. Make sure that the propeller is facing up and away from the structure. Do the same for the upper, right 12” PVC pipe. This can be scene in the image below.

7.) Next, connect a propeller to outside of the left, rearward 8” PVC pipe. Then connect another propeller to the outside of the right, rearward 8” PVC pipe. This can be seen in the image below.
8.) Now, the frame and propulsion should be completely finished. It is now ready to have the robotic arm and tether attached to it.

Rendered Isometric

Calendar 2nd MP

Week of November 11th-17th

• 12th- Contact Mentor
• 13th- Log Update/Start Calendar
• 14th- Finish Calendar
• 15th- Participation/Schedule/Calendar and Log Sheet
  Orthographic Views w/Dimensions and Materials
• 16th- Log Update

Week of November 18th-24th

• 19th-Begin Exploded Drawing
• 20th-Log Update
• 21st-Continue Exploded Drawing
• 22nd-Finish Exploded Drawing
• 23rd-Log Update

Week of November 25th-December 1st

• 26th-Contact Mentor
• 27th-Log Update/Begin Rendered Isometric
• 28th-Continue Rendered Isometric
• 29th-Finish Rendered Isometric
• 30th-Log Update

Week of December 2nd-8th

• 3rd-Contact Mentor
• 4th-Log Update/Begin Plan of Procedures
• 5th-Continue POP
• 6th-Finish POP
• 7th-Log Update

Week of December 9th-15th

• 10th-Contact Mentor
• 11th-Log Update/Begin Bid Process
• 12th-Continue Bid Process
• 13th-Finish Bid Process
• 14th-Log Update

Week of December 16th-22nd

• 17th-Contact Mentor
• 18th-Log Update
• 19th-Developmental Work and Bid Process Due
• 20th-Begin Math and Science Analysis
• 21st-Log Update

Week of December 23rd-29th

• 24th-No School
• 25th-No School
• 26th-No School
• 27th-No School
• 28th-No School

Week of December 30th-January 5th

• 31st-No School
• 1st-No School
• 2nd-Contact Mentor
• 3rd-Continue Math and Science Analysis
• 4th-Log Update/Finish Math and Science Analysis

Week of January 6th-12th

• 7th-Contact Mentor
• 8th-Log Update
• 9th-Create Outline For Presentation
• 10th-Math and Science Analysis Due
• 11th-Log Update

Week of January 13th-19th

• 14th-Contact Mentor
• 15th-Log Update
• 16th-Prepare for Presentations
• 17th-Presentations
• 18th-Log Update/ Presentations

Week of January 20th-26th

• 21st-Presentations
• 22nd-Log Update
• 23rd-Mentor Contacts Due
• 24th-Begin 3rd Marking Period Calendar
• 25th-Log Update
  

Selection/Rejection

I have designed three alternate solutions for the structure and propulsion of an underwater ROV designed to be operated by a team of three. For each solution there is a brief description, along with a list of pros and cons. Each design description will incorporate the propulsion and structure together, for the two go hand in hand.

The first solution is rather simple in nature. The structure is made up of 1” PVC piping. There are two propellers placed internally in the rear of the structure to propell the ROV forward. These also function to steer the ROV to the left or right without using a rudder system. Centered externally on each side of the structure, is a propeller facing up and down. These will aid in the surfacing and submerging of the ROV. The propellers will be those used on the previous year’s ROV.

This solution seems very pratical. The resources necessary are easily available to me and my teammates. Also, the design should be able to perform all the tasks necessary to complete the competition requirements. I like how the inside of the structure is left open to include the robotic arm, lights, video cameras, and anything else necessary for the ROV.

Pros

• The PVC structure will be postively buoyant which is good because it is easier to add weight for buoyancy than to take away weight.


• Able to surface and submerge without needing to move forward.


• Two upward propellers will keep ROV balanced during ascent or decent
  

Cons

• Requires a lot of power to steer the ROV.


• Taking turns slows the ROV due to opposing motion of one propeller.


• Structure may be too positively buoyant.

The second solution is very similar to the first. The structure is also constructed of 1” PVC piping. The structure resembles the skeletal nature of a rectangular prism. Two propellers are used to ascend and descend the underwater ROV. One is located in the bow of the ROV, and the other is located on the stern to ensure that the ROV does not lean back or forth during surfacing. The two propellers located externally on the stern of the ROV are used to propell the ROV forward and rearward. These propellers also function to turn the ROV left and right.

This solution is also very practical to make. It requires the same resources as the first solution. Also, there is no major expertise in certain tools or materials necessary for this design. The only concern I have about this design is that the propeller placed in the front may interfere with the robotic arm, which is also placed in the front of the ROV.

Pros

• Capable to ascend and descend without needing to move forward


• Is light weight and will not require a lot of power to move


• PVC structure will be positively buoyant

Cons

• Requires a lot of power to turn the ROV left and right


• Little space in front for robotic arm, lights, and video cameras


• Turning cause the ROV to slow down
  

The third design is the most complex of the three. This design can be most easily compared to an airplane. On the top are two wings extending over the side. These would be made out of some kind of plastic, such as plexiglass. Under each wing is a propeller to move the ROV back and forth. At the rear of each with is a diving place. These curve up to make the ROV surface and curve down to make it submerge. All the way in the rear of the design is a rudder. This is placed in between the propellers to move the ROV left and right. The bottom is a PVC box which will contain the robotic arm, video cameras, etc.

This solution is rather complex and would be quite difficult to produce. By using the diving planes, the ROV is forced to move forward during surfacing and submerging. Also, since the ROV is so complex then there are more potential problems that I will run into during the production. If something were to happen with the rudder, then the propellers can act as the steering if necessary.

Pros

• Can surface and submerge while moving forward.


• Has less propellers so it uses less power

Cons

• More complex means more problems


• Is heavy and may be negatively buoyant


• Cannot surface when stationary

After looking over the pros and cons of each design, I decided that the first solution seems to be the most practical. However, i felt there was not enough torque to turn the ROV left and right. So i decided to do a combination of the first and second design. The final solution will be the first design, only with the rear propellers located outside the ROV rather than inside

Alternative Solutions

The first solution is rather simple in nature. The structure is made up of 1½” PVC piping. There are two propellers placed internally in the rear of the structure to propell the ROV forward. These also function to steer the ROV to the left or right without using a rudder system. Centered externally on each side of the structure, is a propeller facing up and down. These will aid in the surfacing and submerging of the ROV. The propellers will be those used on the previous year’s ROV.


The second solution is very similar to the first. The structure is also constructed of 1½” PVC piping. The structure resembles the skeletal nature of a rectangular prism. Two propellers are used to ascend and descend the underwater ROV. One is located in the bow of the ROV, and the other is located on the stern to ensure that the ROV does not lean back or forth during surfacing. The two propellers located externally on the stern of the ROV are used to propell the ROV forward and rearward. These propellers also function to turn the ROV left and right.

The third design is the most complex of the three. This design can be most easily compared to an airplane. On the top are two wings extending over the side. These would be made out of some kind of plastic, such as plexiglass. Under each wing is a propeller to move the ROV back and forth. At the rear of each with is a diving place. These curve up to make the ROV surface and curve down to make it submerge. All the way in the rear of the design is a rudder. This is placed in between the propellers to move the ROV left and right. The bottom is a PVC box which will contain the robotic arm, video cameras, etc.

Brainstorming

All three designs for the frame and propulsion of the ROV are similar in several ways. One way is that all of the frames are skeletal in nature. What the means is that there are no outer covering on any of the designs, only the frame itself. Also, all of the ROV designs are meant to be made of aluminum structure. Another way they are all similar is that for propulsion, a propeller is used rather than any other instruments of propulsion. In all designs, supports can be added for the cameras, lights, robotic arm, etc.

The first design is shaped like a rectangular prism. The propeller is located inside the structure of the ROV. It is also located in the rear of the ROV to push the ROV forward.

The second design is similar to the first. The structure is shaped like a rectangular prism. This design also has a tail, onto which the propeller is mounted. The propeller pushes the ROV like in the first design. However, in this design, the propeller is located on the outside of the structure rather than inside.

The third design is also rectangular in nature. Rather than having a tail, this design has an aluminum nose. The propeller is located inside the nose of the structure. From here, the propeller pulls the ROV rather than pushing. This will provide more control over the ROV, similar to how front wheel drive has more control than rear wheel drive in automobiles

Testing Procedures

Expectations:

There will be a number of different aspects of the underwater ROV that will be tested before competing in the MATES competition. The testing procedures will be done at the Monmouth University swimming pool located on campus in the gymnasium. The ROV structure will be expected to support the weight of every object that will be mounted to it. The ROV propulsion will be expected to move the ROV in all directions, with and without added weight. The following testing procedures are specifically for the structure and the propulsion of the underwater ROV.

The picture above is the Monmouth University Swimming Pool
(Photo taken by me and my teammate)

Set-up

1. Assemble structure if necessary


2. Mount the propellers, robotic arm, video cameras, ect. to the structure


3. Attach tether to the ROV
   

Structure Testing Procedures

1. Add ten pounds to structure to make sure it is supportive.


2. Lift the ROV with two people to make sure it can be lowered into the water without a mechanical aid.


3. Put into water for buoyancy check. The ROV should have slight, positive buoyancy. This means that it will stay submerge to about 3 feet and then stay afloat there. If the ROV fails to submerge to 3 feet, then weight will need to be added to the ROV. If, on the other hand, the ROV sinks too deep, then a positively buoyant substance will need to be added to the ROV.
   

Propulsion Testing Procedures:

1. Move the ROV forward. Observe whether the ROV falls off to the right or the left.


2. Move the ROV in reverse. Observe whether the ROV falls off to the right or the left


3. Have ROV turn right


4. Have ROV turn left


5. Have ROV submerge all the way to bottom of swimming pool.


6. Have ROV surface from the bottom of the swimming pool.


7. Have ROV submerge to bottom again. This time pick up a 10 pound object from the pool floor.


8. Have the ROV surface from the bottom, while holding the 10 pounds object.

Summer Research

Buoyancy:
If the weight of an object is less than the weight of the fluid the object would displace if it were fully submerged, then the object has an average density less than the fluid and has a buoyancy greater than its weight. If the fluid has a surface, such as water in a lake or the sea, the object will float at a level so it displaces the same weight of fluid as the weight of the object. If the object is immersed in the fluid, such as a submerged submarine or a balloon in the air, it will tend to rise. If the object has exactly the same density as the liquid, then its buoyancy equals its weight. It will tend neither to sink nor float. An object with a higher average density than the fluid has less buoyancy than weight and it will sink. A ship floats because although it is made of steel, which is denser than water, it encloses a volume of air and the resulting shape has an average density less than that of the water.

Welding:
Base-metal preparation: To weld aluminum, operators must take care to clean the base material and remove any aluminum oxide and hydrocarbon contamination from oils or cutting solvents. Aluminum oxide on the surface of the material melts at 3,700 F while the base-material aluminum underneath will melt at 1,200 F. Therefore, leaving any oxide on the surface of the base material will inhibit penetration of the filler metal into the workpiece.
To remove aluminum oxides, use a stainless-steel bristle wire brush or solvents and etching solutions. When using a stainless-steel brush, brush only in one direction. Take care to not brush too roughly: rough brushing can further imbed the oxides in the work piece. Also, use the brush only on aluminum work-don't clean aluminum with a brush that's been used on stainless or carbon steel. When using chemical etching solutions, make sure to remove them from the work before welding. To minimize the risk of hydrocarbons from oils or cutting solvents entering the weld, remove them with a degreaser. Check that the degreaser does not contain any hydrocarbons.

Hydraulics:
The basic idea behind any hydraulic system is very simple: Force that is applied at one point is transmitted to another point using an incompressible fluid. The fluid is almost always an oil of some sort. The force is almost always multiplied in the process. The picture below shows the simplest possible hydraulic system: (Figure 4)
A Simple hydraulic system consisting of two pistons and an oil-filled pipe connecting them. If you apply a downward force to one piston (the left one in this drawing), then the force is transmitted to the second piston through the oil in the pipe. Since oil is incompressible, the efficiency is very good -- almost all of the applied force appears at the second piston. The great thing about hydraulic systems is that the pipe connecting the two cylinders can be any length and shape, allowing it to snake through all sorts of things separating the two pistons. The pipe can also fork, so that one master cylinder can drive more than one slave cylinder if desired.

Direct Current
Direct current is the constant flow of electric charge. This is typically in a conductor such as a wire, but can also be through semiconductors, insulators, or even through a vacuum as in electron or ion beams. In direct current, the electric charges flow in the same direction. Direct current installations usually have different types of sockets, switches, and fixtures, mostly due to the low voltages used, from those suitable for alternating current. It is usually important with a direct current appliance not to reverse polarity unless the device has a diode bridge to correct for this. DC is commonly found in many low-voltage applications, especially where these are powered by batteries, which can produce only DC.

Propulsion
A propeller is essentially a type of fan which transmits power by converting rotational motion into thrust for propulsion of a submarine through a fluid such as water, by rotating two or more twisted blades about a central shaft, in a manner analogous to rotating a screw through a solid. The blades of a propeller act as rotating wings and produce force through application of both Bernoulli's principle and Newton's third law, generating a difference in pressure between the forward and rear surfaces of the airfoil-shaped blades and by accelerating a mass of water rearward.
Water jet propulsion is a type of propulsion in which water is pumped through a nozzle, which propels the vehicle forward. Jet propulsion is especially useful in shallow waters.

Background Info

Remotely operated underwater vehicles (ROVs) are the common accepted name for tethered underwater robots in the offshore industry. ROVs are unoccupied, highly maneuverable and operated by a person aboard a vessel. They are linked to the ship by a tether, like the one scene in Figure 2. A tether is a group of cables that carry electrical power, video, and data signals back and forth between the operator and the vehicle. High power applications will often use hydraulics in addition to electrical cabling. Most ROVs are equipped with at least a video camera and lights. Additional equipment is commonly added to expand the vehicle’s capabilities. These may include sonar, magnetometers, a still camera, a manipulator or cutting arm, water samplers, and instruments that measure water clarity, light penetration and temperature.












(Figure 1) (Figure 2)

ROVs range in size from that of a bread box to a small truck. Deployment and recovery operations range from simply dropping the ROV over the side of a small boat to complex deck operations involving large winches for lifting and A-frames to swing the ROV back onto the deck. Some even have “garages” that are lowered to the bottom. The cabled ROV then leaves the garage to explore, returning when the mission is completed. In most cases, however, ROV operations are simpler and safer to conduct than any type of occupied-submersible or diving operation.
Conventional ROVs are constructed with a large flotation pack on top of a steel or alloy chassis, to provide the necessary buoyancy. Syntactic foam is often used for the flotation. A tool sled may be fitted at the bottom of the system and can accommodate a variety of sensors. By placing the light components on the top and the heavy components on the bottom, the overall system has a large separation between the center of buoyancy and the center of gravity; this provides stability and the stiffness to do work underwater. Electrical cables may be run inside oil-filled tubing to protect them from corrosion in seawater. Thrusters are usually located in all three axes to provide full control. Cameras, lights and manipulators are on the front of the ROV or occasionally in the rear for assistance in maneuvering.




(Figure 3)


The disadvantages of using an ROV include the fact that the human presence is lost, making visual surveys and evaluations more difficult, and the lack of freedom from the surface due to the ROV’s cabled connection to the ship. An ROV operator controls the vehicle from a system on board the ship. Using a joystick, a camera control, and a video monitor, the operator moves the vehicle and the camera to desired locations; the operator’s eyes essentially “become” the camera lens.

Limitations

Structure

• The ROV must be able to move without electrical devices
• The ROV will contain at least three video cameras on board
• The ROV can have no onboard power except for lights

Propulsion

• The ROV will operate on less than 13 volts of power 25 amps
• The ROV must function on DC voltage
• The ROV must be able to move without electrical devices
  
  
  

Specifications

Structure:

• The ROV must be able to submerge and surface between depths of 4 meters
• The ROV must be capable of performing in varying water temperatures
• The ROV must be able to be assembled within five minutes
• The ROV must be slightly positive in buoyancy
• The ROV must be capable of supporting a mechanical arm

Propulsion:

• The ROV will be remote controlled
• The ROV must pass a safety test set forward by MATES
• The ROV must be able to move in all directions
• The ROV must be capable of performing in varying water temperatures
• The ROV must be able to be assembled within five minutes

Design Brief

To design and create the structure and propulsion of an underwater ROV to be operated by a team of three

Calendar

September:
17th – Weblog created
19th - Contact Mentor
20th – Calendar created and hard copy handed in
21st – Design Brief, Specs & Limitations updated on blog
25th – Weblog update
26th - Contact Mentor and give update
26th – Background info & Summer research updated on blog
27th- Testing Procedures updated on blog
28th – Weblog update

October:
1st- Weblog update
3rd – Brainstorming and Alternate Solutions put on blog
3rd – Outline for presentation
3rd – Testing and Final Solution ideas
5th – Weblog update
6th – Contact Mentor and give update
8th – Weblog update
12th – Weblog update
13th – Contact Mentor and give update
14th – Choose final solution
15th – Weblog update
16th – Contact Mentor and give update
16th – Start Selection/Rejection report
18th – Finish Selection/Rejection report
19th – Start model
19th – Weblog update
23rd – Weblog update
24th – Contact Mentor and give update
24th – Finish model
26th – Weblog update
27th – Contact Mentor and give update
30th – Weblog update
31st – Mentor contacts handed in
31st – Model and Selection/Rejection report finished
31st – Outline for formal presentation

November:
1st – Presentation Day
2nd – Weblog update
5th – Weblog update
9th – Weblog update
9th - Make 2nd Marking Period Calendar
12th - Weblog udate

Test post

Testing