Mach 30 #EngineerSpeak Hangout Nov 14, 2013
Discussion Topic: Catching up on Ground Sphere
Attending: J, Juli, Jeremy, Tim, Matt, Chris, Alicia
Start: 2200
End: 2320
Minutes:
- Introductions
- Report on OSHWA’s legal consultation
- Alicia - wants to address/report on Mach 30 questions
- Alicia - IANAL!!!
- Alicia - her report is below...
- OSHWA had a meeting with Julie Samuels (sp?) from EFF; works to fight “stupid patents” and other lawyers (scholar from NYU who has worked on patent pools for open source)
- started with overview of OSHW
- if OSHW figures out a new standard (something like USB, bluetooth, etc), could obtain a patent for it and then license it openly and make part of the licensing for the patent include enforcement of open provisions
- started a discussion on each of the licenses, but did not go into as much detail about them as Alicia was hoping
- Michael Wineberg from Public Knowledge is probably best legal resource for OSHW
- discussed the ease of use of copyrights and how most OSHW licenses are currently based on copyright; there are limits on what the licenses can protect (especially with respect to instantiations of the hardware itself) - this is especially true of the CERN OHL (still have to wait and see what happens when it is challenged in court)
- also got some pointers
- people are afraid of having OSHW designs getting patented by someone else - if this happens (not sure it has yet, don’t think so) there are steps to take (includes telling USPTO about the OSHW as prior art, if that fails can go to EFF)
- note, OSHWA is looking at setting up a watchdog group to keep an eye out for OSHW in patents and setting up repo of OSHW prior art
- regarding the questions on attribution only style licenses - it is unclear how attribution only licenses would be enforced by the courts without patents being involved; though it is possible that the interpretation from the courts would still fall toward enforcing the license through “social contract” (actually very positive about “social contract”)
- regarding patentable ideas being contributed - started a very interesting conversation, including the idea of a reverse NDA to protect the project managers from this event
- concerning questions about liability to corp or volunteers - that is all warranty/terms of service stuff, so completely different area, best place to address this is in the “warranty” clause (Alicia likes the Arduino clause)
- Tim’s summary on where Skycube is at
- It’s at Houston.
- Scheduled for launch on December 14 from Wallops
- Launch window closes on December 21
- Omega has been sent to Australia
- Not sure when they’ll be deployed from ISS
- Last cubesat was sent in August and is still awaiting deployment
- 3rd week in January is the earliest, end of June is worst case scenario
- Could be operational for 6 months
- SkyCube is not the only CubeSAT operating in this frequency range
- Two satellites using the same radio launching 11/19
- Will make for a good test for GroundSphere
- Expecting a week of shake-down time after deployment from the ISS
- Aaron’s summary on where GroundSphere is at (prototype 1)
- Prototype 1 - Scheduled for 3 complete prototypes before the first kit
- Changes that were made from the first prototype have worked out well
- Ground plan was changed to a conductive ripstop fabric, and is good up to 3 GHz
- Body is plastic conduit that is available at Home Depot
- Everything except the material for the phasing loops and the ground plane fabric can be purchased at Home Depot
- Anticipates being able to pick up the pace and be able to meet the original schedule
- Need to test GroundSphere for repeated acquisition before kitting
- Tim - The fact that the antenna is omni-directional is a big win
- Maybe we should look at separating the parts of the projects i.e. electronics vs antenna
- Chris - Are the three prototypes different phases?
- J - They are progressive builds culminating in the kit
- First prototype - address signal loss issues (proof-of-concept of new preamp at frequency
- Second prototype - Improvements on first shooting for kit
- Three - Address mistakes in prototype two and move to production.
- Chris - Do you have changes in mind already for prototype two?
- Yes - The overall height can be lessened
- Fabric cuts very well. It has an under-fabric to prevent contamination from the underlying frame
- The reflow oven that Aaron got can do 24 of the pre-amps at a time
- J - Wants to have some detailed discussion about the kit business model side of things
- Alicia - Have you used a Robot Craft?
- They’re like a laser cutter for fabric
- Tim - Has access to one
- Jaye - Has thought about using a plastic mesh to support the conductive fabric
- Ethan - Can do a die cut using a screw press
- Tim - Is it expected that the electronics will fit in a project box with a connector to the antenna
- Aaron - Yes, dual gang plastic box with a cover
- PCB board was provided by the kit vendor and Aaron will install the parts
- Aaron - Has a goal to take power off the USB interface for the amp
- Tim - Having something in one box would be another big win
- Aaron - Thinking of using MCX connectors even though makers won’t have ready access to them
- J - Tim, after we’ve demonstrated orbital acquisition we want to get you a prototype to do benchtop testing
- Tim - Yes, there’s software work we want to do
- J - Will allow us to work on the hardware and software in parallel
- Aaron - Needs signal source ASAP
- Tim - Have a radio coming from AstroDev, which could be loaned out, but isn’t here yet
- J - Fan of testing in chunks
- Getting a radio just so that we can test for tone would be important
- Better to test for packet reception as well
- J - How much will a radio that can transmit at 915 MHz cost us?
- Aaron - Not sure yet
- Tim - One option is Blade RF, a higher quality SDR with transmit capability. In the ball park of $400 to $500
- Might be able to get ahold of one of these
- J - Tim, can we get a firm number on the units that need to go to backers