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OpenROV

During the Spring of 2014, students at Twindly Bridge Charter School will build an OpenROV. This was made possible by the generous support of the Paul G. Allen Family Foundation which paid for the lion's share of the materials. For more information regarding how this project was funded as well as pictures and my impact statement, please visit the project page at DonorsChoose.org.

Progress
  • Jan 23rd: We took care of some paperwork, learned a little about how to use the BeagleBone Black (made some LEDs blink in Cloud9) and soldered longer wires to the motors.
  • Jan 30th: Focused on using VNC to remote into the BeagleBone and on sharing the host computer's Internet connection with the BeagleBone in order to install software (such as the Adafruit_BBIO library) . Took a look at cementing some acrylic but decided to wait for the 2.6 instruction set since the pieces pictured in the first steps of the 2.5 instruction set don't match what we have.
  • Feb 6th: Spent time remoting into the BeagleBones again. Wrote scripts to execute commands on the BeagleBone to share Internet and set the date/time so that software installations from repositories work correctly. A couple students began wiring their breadboards with an external LED. Broke into groups to work on various components of the ROV. One group built the internal structure which is now done. Another began work on the battery endcaps. Another began work on the main endcaps and we discovered the instructions were somewhat unclear and incomplete regarding how and why to cut the syringes.
  • Feb 13th: Everybody logged into their Beaglebones in relatively short order and had programs of one kind or another running. Some wired buttons to print messages to the terminal and/or control LEDs. One student was having a little trouble connecting to his Beaglebone via USB so he learned how to plug it directly into the router and connect to it over the network (we spend a lot of time dealing with driver and connection issues). Work on the ROV went well today. The group responsible for the battery tubes just about has them ready to pot with epoxy. The main endcaps are ready to be wired. The tether management system was built, and work began on attaching the ESCs to the controller board.
  • Feb 20th: Two students started out working on their BeagleBones. One went through the process of installing the drivers on his Windows 8 computer while the other tested a DVI to HDMI cable (which worked), and a Wifi dongle (still trying to get this to work). He also tried to get the camera to work, but to no avail as of yet. Another pair of students finished waterproofing the motors and attached them to the internal structure. One student built the topside adapter and another built the electronics chassis. The same student who started attaching the ESCs to the controller board finished today and ended up attached the other end of the adapter and the BeagleBone. She then attached everything to the electronics chassis. We also had a student work with his father to wrap the wire onto the tether management system.
  • Feb 27th: Continuing where he left off last week, one student started working on getting Wifi up and running on his Beaglebone. Eventually we ran into difficulties trying to connect to the school's WPA2 password protected network (we were able to connect to an unprotected network, but Angstrom doesn't seem to handle WPA2 well). So we switched over to using the OpenROV image and he installed the LXDE desktop and xrdp to remote in. Everyone else worked on the robot. One pair mounted the battery tubes and routed and zip tied all the wires for the wire harness. They came in the following day to mount the propeller shrouds. Another pair modified and mounted the servo and attached the LEDs and camera which completed the E-Chassis. And one student prepared the motors for attachment to the propellers. We are now ready to epoxy everything during our next meeting.
  • Mar 6th: Potted all encaps and attached props to motor bells. Put epoxy around the syringe in the endcap without the wire harness and did the same to the endcap with the wire harness Friday morning. After our fun with epoxy, 4 students worked on turning servos with their BeagleBones while another worked on programming random events when a button is pressed and the last started on blinking an external LED.
  • Mar 13th: Spring Break 
  • Mar 20th: One pair of students began soldering wires to the DB-25 connector while another pair tried to assemble the IMU/Depth Module. Unfortunately they were only able to solder a few wires before they had to stop as we have run out of acrylic cement (I bought some as soon as I got home this evening). I helped another student with the lasers once he soldered the wires together, but I mounted them a little too far out, so we will need to redo that step next time. One students took a look at programming the ESCs, but he was unable to move forward since they need to be powered and the DB-25 connector is only half complete. So, he started working getting figuring out how to use a motor driver. Last but not least, a father/son pair did battle with connecting their BeagleBone Black to the Internet using their Wifi dongle.
  • Mar 27th: One student finished the DB-25 connector while another finished the IMU/Depth Module. A third worked with his father to align the lasers. Thereafter we potted the IMU/Depth module and epoxied the lasers into place.
  • Apr 3rd: We put in the batteries and plugged in the computer today. Getting the Cockpit to fire up took a while (had to reseat the homeplug adapter underneath the Beaglebone Black twice). Once that was working the students were able to upload the Arduino software and program the ESCs. Thereafter they calibrated the ESCs, but for some reason the space bar did not stop all of the motors.
  • Apr 10th: We tested the OpenROV in the toolbox/tank we have at the school. Everyone got a chance to drive it for a bit. It hung up a couple of times (not sure why) but we were able to reset it by removing the battery caps and unplugging the topside adapter. Otherwise, everything worked well.
  • Apr 12th: Everyone met at the Wasilla Pool to drive the robot around which was much more exciting than the toolbox/tank. The robot had to be reset once, but other than that, it was a fantastic trip. When we pulled it out of the water we saw where one of the extra wires got caught around a prop, which we will fix before the next dive. There are a few other items we are looking at improving as well, but one step at a time.


To Do List

  • Align lasers and solder broken connection.
  • Buy more batteries (a few were slightly damaged when the fell out of the ROV during a reset).
  • Replace servo (the current one has plastic gears inside-the new one has metal gears).
  • Cut the camera's USB cable down to length.
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