Hi All,
Today I ordered two Turnigy-nano tech 5000mah 3S 35C LiPo batteries from Hobby King, one EC5 Battery Parallel Y-Harness, and two sets of E-Flite EC5 Device/Battery connectors to change the LiPo battery 4mm connectors to the E-Flite EC5 battery connectors and one EC5 device connector for the input cable for the Battery Junction Board.
As soon as these components arrive I will change out the battery connectors with the EC5 connectors, size the length of the Battery Junction Board input cable, and then install a EC5 device connector on the input cable. At this time I will also size the Velcro strap that I will use to hold the two LiPo batteries to the battery sub tray to keep them from shifting around when the ROV chassis rolls.
Now I will be ready to attach the ESC power cables coming from the cable penetrators to the power cables attached to the Battery Junction Board.
As far as the Navigation Controller goes, I am still waiting on the custom Tether that I have on order and I am also considering looking into collaborating with a local electronics developer to design and build inexpensive ROV top side and bottom side navigation control and video boards for hobbyists. I plan to use these in place of my original simple two board ROV control system.
More to come.
Regards,
SSN626B/TCIII
Experimental ROV Design using Blue Robotics Components
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
Since I cannot move forward with the Battery and Navigation Controller portion of the Project until additional components arrive, I thought that I would test the buoyancy and trim of the chassis today.
With an assist from my son-in-law we took the ROV chassis down to the Association swimming pool and gently slipped it into the pool water. In all honesty I was expecting the chassis to start to sink to the bottom of the pool, but much to my surprise it actually floated at a slight angle with about 25 percent of the chassis above water.
I suspect that the Thruster ESC cables, being connected to the WTCs in the rear of the WTCs, is causing the chassis to list slightly towards the stern. So it looks like I am going to have to add some ballast to the chassis even after I add the batteries and the navigation controller to their respect WTCs. However I suspect that not much ballast will be required to reach neutral buoyancy and to trim out the chassis.
Since I plan to add a gripper and lights to the chassis, I think that I will need even less ballast in the long run.
I plan to run a ballast and trim test as I add the additional components, like the batteries, navigation controller, and lights to the chassis and adjust as necessary.
More to come.
Regards,
SSN626B/TCIII
Since I cannot move forward with the Battery and Navigation Controller portion of the Project until additional components arrive, I thought that I would test the buoyancy and trim of the chassis today.
With an assist from my son-in-law we took the ROV chassis down to the Association swimming pool and gently slipped it into the pool water. In all honesty I was expecting the chassis to start to sink to the bottom of the pool, but much to my surprise it actually floated at a slight angle with about 25 percent of the chassis above water.
I suspect that the Thruster ESC cables, being connected to the WTCs in the rear of the WTCs, is causing the chassis to list slightly towards the stern. So it looks like I am going to have to add some ballast to the chassis even after I add the batteries and the navigation controller to their respect WTCs. However I suspect that not much ballast will be required to reach neutral buoyancy and to trim out the chassis.
Since I plan to add a gripper and lights to the chassis, I think that I will need even less ballast in the long run.
I plan to run a ballast and trim test as I add the additional components, like the batteries, navigation controller, and lights to the chassis and adjust as necessary.
More to come.
Regards,
SSN626B/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
For those of you with a GoPro HD/2 or GoPro 3/3+/4 and would like to use your GoPro on your ROV, you might want to checkout the GoPro watertight housings offered by Eye of Minehttp://www.eyeofmineactioncameras.com/c ... s/1817.htm.
These housings have a SD composite video connection to the back of the camera housing and are good down to 200 feet. The SD composite video cable is 5 mm in diameter and will easily fit into a BR cable penetrator. The SD composite video can then be brought into the WTC through the cable penetrator and then connected to the ROV Tether. The nice thing about this housing is that the camera can be positioned anywhere on the ROV chassis and the GoPro can record HD video on the removable SD card, for later review, while streaming the live SD composite video topside.
Regards,
SSN626B/TCIII
For those of you with a GoPro HD/2 or GoPro 3/3+/4 and would like to use your GoPro on your ROV, you might want to checkout the GoPro watertight housings offered by Eye of Minehttp://www.eyeofmineactioncameras.com/c ... s/1817.htm.
These housings have a SD composite video connection to the back of the camera housing and are good down to 200 feet. The SD composite video cable is 5 mm in diameter and will easily fit into a BR cable penetrator. The SD composite video can then be brought into the WTC through the cable penetrator and then connected to the ROV Tether. The nice thing about this housing is that the camera can be positioned anywhere on the ROV chassis and the GoPro can record HD video on the removable SD card, for later review, while streaming the live SD composite video topside.
Regards,
SSN626B/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
Today I removed the 4 mm bullet connectors that came with the HK Turnigy 5000mah 3S LiPo batteries and replaced them with E-Flite EC5 battery connectors that can handle up to 120 amps and are much easier to connect and disconnect. I also reworked the battery hold down strap slot in the battery sub tray so that there is now both one on the top and one on the bottom of the tray. I purchased a set of these Velcro black cable straps to hold the horizontally stacked batteries in position on the battery sub tray. A picture of the battery sub tray with batteries is shown below:
As far as the ballast effort goes, I purchased a 2 foot long piece of 1 1/4" ID diameter PVC at Home Depot and four rounded end caps. After doing a little math I decided to slice a 17 inch section off the original 2 foot piece. I then attached a rounded end cap to one end of the tube and began to fill the tube with my bb supply. I was able to use almost all of the bbs (~5 pounds) to fill the 17 inch long tube before I had to put the other end cap on the tube. If I drill a hole in one of the end caps, I can fill the tube almost all the way to the top with bbs and then use the Loctite marine grade epoxy to seal the hole off. But in the meantime I will keep the end cap just pressed on until I see if this 5 pound ballast tube will get the ROV Chassis close to neutral density. Though I think that it is going to take two 5 pound tubes of ballast to get the ROV Chassis close to neutral density.
More to come.
Regards,
SSN626B/TCIII
Today I removed the 4 mm bullet connectors that came with the HK Turnigy 5000mah 3S LiPo batteries and replaced them with E-Flite EC5 battery connectors that can handle up to 120 amps and are much easier to connect and disconnect. I also reworked the battery hold down strap slot in the battery sub tray so that there is now both one on the top and one on the bottom of the tray. I purchased a set of these Velcro black cable straps to hold the horizontally stacked batteries in position on the battery sub tray. A picture of the battery sub tray with batteries is shown below:
As far as the ballast effort goes, I purchased a 2 foot long piece of 1 1/4" ID diameter PVC at Home Depot and four rounded end caps. After doing a little math I decided to slice a 17 inch section off the original 2 foot piece. I then attached a rounded end cap to one end of the tube and began to fill the tube with my bb supply. I was able to use almost all of the bbs (~5 pounds) to fill the 17 inch long tube before I had to put the other end cap on the tube. If I drill a hole in one of the end caps, I can fill the tube almost all the way to the top with bbs and then use the Loctite marine grade epoxy to seal the hole off. But in the meantime I will keep the end cap just pressed on until I see if this 5 pound ballast tube will get the ROV Chassis close to neutral density. Though I think that it is going to take two 5 pound tubes of ballast to get the ROV Chassis close to neutral density.
More to come.
Regards,
SSN626B/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
The weather here in southern Florida has turned cool, cloudy, and slightly rainy so I have been unable to test my ROV chassis in the Association swimming pool with the newly constructed 5 pound ballast.
However while I have been waiting for the weather to clear up I have had a chance to test a new Blue Robotics product designed to simplify the vacuum testing of WTCs. Unlike the original vacuum tube adapters which consisted of a 1/4 X 1/4 tubing coupler epoxied into a 6 mm cable penetrator, this vacuum tube adapter takes the place of the screw-in plug used in the enclosure vent so there is no additional cable penetrator to install for testing as before. The pictures below show the vacuum tube adapter and its installation in the enclosure vent:
Vacuum Plug with O rings and Test Plug
Vacuum Tube Adapter installed in Enclosure Vent
Once I got my vacuum pump, gauge, and cutoff valve attached to the new vacuum tube adapter I pumped the Battery Compartment WTC down to 560 mm Hg, shut the vacuum cutoff valve, and waited for an hour. Just like when using the original vacuum tube adapter, the vacuum gauge reading remained at 560 mm Hg and I am sure that it will show a loss of around 20 mm Hg after 24 hours just like the original setup due to the vacuum cutoff valve leaking.
I must commend Rusty on his ingenuity concerning the design of this vacuum tube adapter which has now made the vacuum testing of the BR WTC a slam dunk.
Regards,
SSN626/TCIII
The weather here in southern Florida has turned cool, cloudy, and slightly rainy so I have been unable to test my ROV chassis in the Association swimming pool with the newly constructed 5 pound ballast.
However while I have been waiting for the weather to clear up I have had a chance to test a new Blue Robotics product designed to simplify the vacuum testing of WTCs. Unlike the original vacuum tube adapters which consisted of a 1/4 X 1/4 tubing coupler epoxied into a 6 mm cable penetrator, this vacuum tube adapter takes the place of the screw-in plug used in the enclosure vent so there is no additional cable penetrator to install for testing as before. The pictures below show the vacuum tube adapter and its installation in the enclosure vent:
Vacuum Plug with O rings and Test Plug
Vacuum Tube Adapter installed in Enclosure Vent
Once I got my vacuum pump, gauge, and cutoff valve attached to the new vacuum tube adapter I pumped the Battery Compartment WTC down to 560 mm Hg, shut the vacuum cutoff valve, and waited for an hour. Just like when using the original vacuum tube adapter, the vacuum gauge reading remained at 560 mm Hg and I am sure that it will show a loss of around 20 mm Hg after 24 hours just like the original setup due to the vacuum cutoff valve leaking.
I must commend Rusty on his ingenuity concerning the design of this vacuum tube adapter which has now made the vacuum testing of the BR WTC a slam dunk.
Regards,
SSN626/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
Today I was able to check the buoyancy of the ROV Chassis with the batteries installed in the Battery Compartment WTC and with the 5 pound ballast PVC tube.
With the batteries installed in their normal position in the Battery Compartment WTC the chassis still had some positive buoyancy, but the chassis was now trimmed fore and after whereas before it was tilting towards the stern due to the weight of the cables/cable penetrators in the WTC rear End Caps.
Addition of the 5 pound PVC tube at the center of the longitudinal axis of the chassis caused the chassis to maintain its trim, but be just slightly submerged indicting that I was now getting close to neutral or slightly positive buoyancy.
I will now empty the bbs from the 5 pound ballast PVC tube, cut it in half, fill each half with the bbs, and seal the ends of both tubes. The two tubes will be mounted on the bottom of the chassis at the center of its longitudinal axis. This should result in a ROV chassis that is trim fore and aft and is very close, if not at neutral buoyancy.
Now someone might point out that I have not included the Navigation Controller hardware which could add some slightly negative buoyancy, however I do not doubt that the addition of a slight amount of negative or positive buoyancy can be easily compensated for.
More to come.
Regards,
SSN626B/TCIII
Today I was able to check the buoyancy of the ROV Chassis with the batteries installed in the Battery Compartment WTC and with the 5 pound ballast PVC tube.
With the batteries installed in their normal position in the Battery Compartment WTC the chassis still had some positive buoyancy, but the chassis was now trimmed fore and after whereas before it was tilting towards the stern due to the weight of the cables/cable penetrators in the WTC rear End Caps.
Addition of the 5 pound PVC tube at the center of the longitudinal axis of the chassis caused the chassis to maintain its trim, but be just slightly submerged indicting that I was now getting close to neutral or slightly positive buoyancy.
I will now empty the bbs from the 5 pound ballast PVC tube, cut it in half, fill each half with the bbs, and seal the ends of both tubes. The two tubes will be mounted on the bottom of the chassis at the center of its longitudinal axis. This should result in a ROV chassis that is trim fore and aft and is very close, if not at neutral buoyancy.
Now someone might point out that I have not included the Navigation Controller hardware which could add some slightly negative buoyancy, however I do not doubt that the addition of a slight amount of negative or positive buoyancy can be easily compensated for.
More to come.
Regards,
SSN626B/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
I completed splitting the 5 pound 17 inch ballast tube in half and fabricated two 8 1/2 inch tubes that weigh approximately 43 ounces (2.7 pounds) each for a total of approximately 5.4 pounds of ballast.
Each ballast tube is mounted on the bottom of the ROV Chassis at the mid point of the longitudinal axis of the Chassis. The picture below will give you an idea of the ballast tube construction and their mounting location on the Chassis:
Ballast Tubes mounted on the bottom of the ROV Chassis
The ballast tubes are a slip fit in their U shaped clamps and can be moved fore and aft to help trim the Chassis. I plan to use tie raps around the tubes on either side of the cross brace, on which the tubes are mounted, to keep the tubes from sliding in the U shaped mount.
This weekend I plan to finish the Battery Tray and connect the Power Junction Board cables to their respective cable penetrator cable connections and complete sizing the length of and installing the connector on the Power Junction Board battery input cable.
More to come.
Regards,
SSN626B/TCIII
I completed splitting the 5 pound 17 inch ballast tube in half and fabricated two 8 1/2 inch tubes that weigh approximately 43 ounces (2.7 pounds) each for a total of approximately 5.4 pounds of ballast.
Each ballast tube is mounted on the bottom of the ROV Chassis at the mid point of the longitudinal axis of the Chassis. The picture below will give you an idea of the ballast tube construction and their mounting location on the Chassis:
Ballast Tubes mounted on the bottom of the ROV Chassis
The ballast tubes are a slip fit in their U shaped clamps and can be moved fore and aft to help trim the Chassis. I plan to use tie raps around the tubes on either side of the cross brace, on which the tubes are mounted, to keep the tubes from sliding in the U shaped mount.
This weekend I plan to finish the Battery Tray and connect the Power Junction Board cables to their respective cable penetrator cable connections and complete sizing the length of and installing the connector on the Power Junction Board battery input cable.
More to come.
Regards,
SSN626B/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
Today, with the help of my son-in-law, I was able to check the ROV Chassis buoyancy and trim by immersing it in the Association swimming pool.
The addition of the two 2.7 pound ballast tubes to the bottom of the Chassis brought the buoyancy of the Chassis to a point such that the top of the Chassis was just awash in the pool water. This level of buoyancy puts the two vertical Thrusters just about three inches below the surface of the water. Also the present buoyancy is such that when the Chassis is manually forced downward into the water, it will slowly rise back to a point where the top of the Chassis is just slightly above the pool surface.
The following two pictures will give an idea of the ROVs present buoyancy:
ROV Chassis with the two 2.7 pound Ballast Tubes attached
The ROV Chassis is just slightly awash
Once the Chassis has dried off I will begin installing the Battery Compartment Battery Tray and then move on to the Navigation Controller Compartment Controller Tray.
More to come.
Regards,
SSN626B/TCIII
Today, with the help of my son-in-law, I was able to check the ROV Chassis buoyancy and trim by immersing it in the Association swimming pool.
The addition of the two 2.7 pound ballast tubes to the bottom of the Chassis brought the buoyancy of the Chassis to a point such that the top of the Chassis was just awash in the pool water. This level of buoyancy puts the two vertical Thrusters just about three inches below the surface of the water. Also the present buoyancy is such that when the Chassis is manually forced downward into the water, it will slowly rise back to a point where the top of the Chassis is just slightly above the pool surface.
The following two pictures will give an idea of the ROVs present buoyancy:
ROV Chassis with the two 2.7 pound Ballast Tubes attached
The ROV Chassis is just slightly awash
Once the Chassis has dried off I will begin installing the Battery Compartment Battery Tray and then move on to the Navigation Controller Compartment Controller Tray.
More to come.
Regards,
SSN626B/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
I have completed the battery and control signal interconnections so I can separate the Battery and Navigation Controller Tray connections from their respective ESC power and signal cables.
I will now power up each ESC individually and control it with my trusty servo PWM controller. Once I have determined that each ESC will respond to PWM input, I will program each ESC with its own individual I2C address (0x29 - 0x38). Each ESC comes with a default I2C address of 0x29. The ESC I2C address reprogramming is performed using the ESC PWM control signal per Blue Robotic's BlueESC Documentation.
Once I have completed the ESC I2C address reprogramming, I will test each ESC over its I2C control signal connection using an Arduino Uno R3 and a program available from the BlueESC Documentation.
More to come.
Regards,
SSN626B/TCIII
I have completed the battery and control signal interconnections so I can separate the Battery and Navigation Controller Tray connections from their respective ESC power and signal cables.
I will now power up each ESC individually and control it with my trusty servo PWM controller. Once I have determined that each ESC will respond to PWM input, I will program each ESC with its own individual I2C address (0x29 - 0x38). Each ESC comes with a default I2C address of 0x29. The ESC I2C address reprogramming is performed using the ESC PWM control signal per Blue Robotic's BlueESC Documentation.
Once I have completed the ESC I2C address reprogramming, I will test each ESC over its I2C control signal connection using an Arduino Uno R3 and a program available from the BlueESC Documentation.
More to come.
Regards,
SSN626B/TCIII
Re: Experimental ROV Design using Blue Robotics Components
Hi All,
Good news! Today I confirmed the functionality of each Thruster by controlling them one at a time using their PWM inputs.
Following the instructions on the Blue Robotics website for the BlueESC, I powered up my trusty servo tester first, with its output set to 1500us (neutral) before applying power to each Thruster. I checked each Thruster for forward and reverse performance and was satisfied that each thruster performed as expected.
The next step will be to program each Thruster, using the PWM control signal line as a serial input, with its own unique I2C address between the range of 0x29 - 0x38. The programming will require an Arduino Uno and a PC or laptop. The programming application (either avrdude or KKMulticopter Tool) on the PC/laptop will communicate with each individual Thruster through a program on the Arduino Uno called ArduinoUSBLinker.
More to come.
Regards,
SSN626B/TCIII
Good news! Today I confirmed the functionality of each Thruster by controlling them one at a time using their PWM inputs.
Following the instructions on the Blue Robotics website for the BlueESC, I powered up my trusty servo tester first, with its output set to 1500us (neutral) before applying power to each Thruster. I checked each Thruster for forward and reverse performance and was satisfied that each thruster performed as expected.
The next step will be to program each Thruster, using the PWM control signal line as a serial input, with its own unique I2C address between the range of 0x29 - 0x38. The programming will require an Arduino Uno and a PC or laptop. The programming application (either avrdude or KKMulticopter Tool) on the PC/laptop will communicate with each individual Thruster through a program on the Arduino Uno called ArduinoUSBLinker.
More to come.
Regards,
SSN626B/TCIII