Sunday, November 18, 2018

JureZ's 13" Nutball

Extracts from RCG:

Mine is 61g AUW , 13" dia. Dollar tree foam with paper off.

using UMX HW and 1S brushed motor and prop ( don't remember which one is the donor...)
had to put six pennies under the nose to get proper CG.
Is windy today to say much about it besides that it is tossed around like a leaf... it flies anyway ...

---
it flew fine, nicely slow, a floater... until I managed to damage the propeller. Grounded for now...

https://static.rcgroups.net/forums/attachments/4/8/6/8/1/9/a11335684-255-UMX%20Nutball.JPG

---
and here is a video, after switching to a 10g brushless motor (custom rewound, Y , 36 Turns per tooth, Kv= 635 RPM/V ) , 
10 A ESC,
Battery 2S 300 mAh 30C, 
APC 7*3.8 SF Propeller , 
FrSky 4 Channel RX.
two UMX Spectrum Linear Servos ,
82g AUW, wing loading = 3.16 oz/sq ft , 
Static test current draw at full throttle : 2.2A @ 8V , 17.6W into the ESC.

https://www.youtube.com/watch?v=qDRXXUVhvio

Thursday, October 25, 2018

Phoenix 1600 ESC Brake programming

The ESC is programmed from the factory to have prop brake OFF.

TO PROGRAM THE ESC FOR PROP BRAKE: Turn radio and plane off. Turn radio on and put throttle at FULL throttle. Turn plane on. You will hear some tones indicating that the ESC is in "programming" mode. The first tone is a simple beep tone (with just one beep if I recall).

When it changes to a different tone/number of beeps (i.e., the SECOND type of beeping that is DIFFERENT from the first type of beeping - this second beeping is a triplet beep (e.g., dit-dit-dit) if I recall), this is when you want to yank the throttle to the lowest point of its throw. This will turn the prop brake ON.

Then, when you're flying in thermals or slope lift, and you pull throttle down to off, the prop brake will engage and your folding props will fold and now your FPV cam will not be obstructed by the prop spinning.

-- courtesy of Pianoman at RCG

Thursday, September 20, 2018

Shunda TEC-06 Battery Tester



Operation:

  • current used in AH.  Press to start Mode 1 testing.
  • battery voltage. No testing, current voltage.  Mode 1: open circuit voltage (no load). Mode 2: voltage under load.  Press to start Mode 2 testing.
  • final voltage.  Testing stops at this voltage.
  • discharge current in mA.  50-3500.
  • internal resistan in Ω. Reported in Mode 1 with 4-wire harness.

Best reference:
Reverse engineered serial protocol:

Wednesday, July 25, 2018

EastBay RC Guide to Sections 343 and 344.

Disclaimer: I am not a lawyer, etc.  Here's my layman's interpretation of sections 343 and 344 of this document: https://www.congress.gov/bill/115th-congress/house-bill/4/text.  Note that I'm not expressing any opinions, just trying to understand what the bill says.

The top part is my interpretation, followed by my interpretation inlined with original text. Did I come close to getting it right? Let me know what you think!


SEC. 343. SPECIAL RULES FOR MODEL AIRCRAFT.
FAA can't make rules regarding model aircraft. except as noted here.


FAA can require you to register and put your registration number on your aircraft.


FAA can make rules if you have an autopilot or BLOS (beyond line of sight) features and you meet these requirements: fly as a hobby, join a CBO, fly with their rules, less than 55 lbs, fly safely, don't fly over amusement parks, tell airport operators when you're flying nearby. See section 344 below if you don't meet these requirements.


When FAA has an "automated airspace authorization system" you have to use it, unless you're at an approved "permanent location".


CBO-sponsored educational stuff is simple model flying even if you're paid, e.g. sponsored pilots.

They can come after anyone endangering safety, no matter what.


CBOs are nonprofits who further model aviation, provide safety guidelines, support local clubs, and provide support for developing local flying sites.


FAA will publish recognition guidelines for CBOs.
This all becomes effective when the Act passes.


SEC. 344. RECREATIONAL UAS.
This if for everyone who doesn't meet the requirements in section 343 (above) or part 107 (which talks about commercial operations).  I think this is the section that will apply to non-AMA members.


Within 120 days, FAA will issue rules regarding this category of flying, as detailed below.
You have to take an online class.
It's OK if you're under 16.
When "automated airspace authorization system" is implemented, you have to use it.
FAA can't require special licensing, exams, certifications, etc.


---------------------------------------------------------------------------------------------------------


The following is the comments above, inlined with the text at https://www.congress.gov/bill/115th-congress/house-bill/4/text


SEC. 343. SPECIAL RULES FOR MODEL AIRCRAFT.
(a) In General.—Notwithstanding any other provision of law relating to the incorporation of unmanned aircraft systems into Federal Aviation Administration plans and policies, including this subtitle, the Administrator of the Federal Aviation Administration may not promulgate any rule or regulation regarding a model aircraft or an aircraft being developed as a model aircraft,


FAA can't make rules regarding model aircraft. Same as before, but with exceptions below.


except for—
(1) rules regarding the registration of certain model aircraft pursuant to section 44103; and


FAA can require you to register and put your registration number on your aircraft.


(2) rules regarding unmanned aircraft that by design provide advanced flight capabilities enabling active, sustained, and controlled navigation of the aircraft beyond the visual line of sight of the operator, if—
(A) the aircraft is flown strictly for hobby or recreational use;
(B) the model aircraft operator is a current member of a community-based organization and whose aircraft is operated in accordance with the organization’s safety rules;
(C) the aircraft is limited to not more than 55 pounds unless otherwise certified through a design, construction, inspection, flight test, and operational safety program administered by a community-based organization;
(D) the aircraft is operated in a manner that does not interfere with and gives way to any manned aircraft;
(E) the aircraft is not operated over or within the property of a fixed site facility that operates amusement rides available for use by the general public or the property extending 500 lateral feet beyond the perimeter of such facility unless the operation is authorized by the owner of the amusement facility; and
(F) when flown within 5 miles of an airport, the operator of the aircraft provides the airport operator and the airport air traffic control tower (when an air traffic facility is located at the airport) with prior notice of the operation (model aircraft operators flying from a permanent location within 5 miles of an airport should establish a mutually agreed upon operating procedure with the airport operator and the airport air traffic control tower (when an air traffic facility is located at the airport)).
FAA can make rules if you have an autopilot or BLOS features and you meet these requirements: fly as a hobby, join a CBO, fly with their rules, less than 55 lbs, fly safely, don't fly over amusement parks, tell airport operators when you're flying nearby. See next section if you don't meet these requirements.


(b) Automated Instant Authorization.—When the FAA has developed and implemented an automated airspace authorization system for the airspace in which the operator wants to operate, the model aircraft operator shall use this system for authorization to controlled airspace unless flown—
(1) at a permanent location agreed to by the Administrator; and
(2) in accordance with a mutually agreed upon operating procedure established with the airport operator and the airport air traffic control tower (when an air traffic facility is located at the airport).


When they have an "automated airspace authorization system" you have to use it, unless you're at an approved "permanent location".


(d) Commercial Operation For Instructional Or Educational Purposes.—A flight of an unmanned aircraft shall be treated as a flight of a model aircraft for purposes of subsection (a) (regardless of any compensation, reimbursement, or other consideration exchanged or incidental economic benefit gained in the course of planning, operating, or supervising the flight), if the flight is—
(1) conducted for instructional or educational purposes; and
(2) operated or supervised by a member of a community-based organization recognized pursuant to subsection (e).


CBO-sponsored educational stuff is simple model flying even if you're paid, e.g. sponsored pilots.


(e) Statutory Construction.—Nothing in this section may be construed to limit the authority of the Administrator to pursue enforcement action against persons operating model aircraft who endanger the safety of the national airspace system.


They can come after anyone endangering safety, no matter what.


(f) Community-Based Organization Defined.—In this section, the term “community-based organization” means a nationwide membership-based association entity that—
(1) is described in section 501(c)(3) of the Internal Revenue Code of 1986;
(2) is exempt from tax under section 501(a) of the Internal Revenue Code of 1986;
(3) the mission of which is demonstrably the furtherance of model aviation;
(4) provides a comprehensive set of safety guidelines for all aspects of model aviation addressing the assembly and operation of model aircraft and that emphasize safe aeromodeling operations within the national airspace system and the protection and safety of individuals and property on the ground, and may provide a comprehensive set of safety rules and programming for the operation of unmanned aircraft that have the advanced flight capabilities enabling active, sustained, and controlled navigation of the aircraft beyond visual line of sight of the operator;
(5) provides programming and support for any local charter organizations, affiliates, or clubs; and
(6) provides assistance and support in the development and operation of locally designated model aircraft flying sites.


CBOs are nonprofits who further model aviation, provide safety guidelines, support local clubs, and provide support for developing local flying sites.


(g) Recognition Of Community-Based Organizations.—In collaboration with aeromodelling stakeholders, the Administrator shall publish an advisory circular within 180 days of enactment that identifies the criteria and process required for recognition of nationwide community-based organizations. This recognition shall be in the form of a memorandum of agreement between the FAA and each community-based organization and does not require regulatory action to implement.


FAA will publish recognition guidelines for CBOs.


(h) Effective Date.—Except for rules to implement remote identification for unmanned aircraft that by design provide advanced flight capabilities enabling active, sustained, and controlled navigation of the aircraft beyond the visual line of sight of the operator and for rules regarding the registration of certain model aircraft pursuant to section 44103, this section shall become effective when the rule, referred to in section 532 of the FAA Reauthorization Act of 2018, regarding revisions to part 107 of title 14, Code of Federal Regulations, becomes final.


This all becomes effective when the Act passes.


SEC. 344. RECREATIONAL UAS.
(a) In General .—Not later than 120 days after the date of enactment of this Act, the Administrator of the Federal Aviation Administration shall issue rules and regulations relating to small UAS flown for recreational or educational use, and that are not operated within all of the criteria outlined in the special rule for model aircraft in section 45505 of title 49, United States Code, or the requirements of part 107 of title 14, Code of Federal Regulations.


This if for everyone who doesn't meet the requirements in section 343 (above) or part 107 (which talks about commercial operations).  I think this is the section that will apply to non-AMA members.


Within 120 days, FAA will issue rules regarding this category of flying, as detailed below.


(b) Regulatory Authority.—When issuing the rules and regulation pursuant to this section, the Administrator shall—
(1) require the completion of an online or electronic educational tutorial that is focused on knowledge of the primary rules necessary for the safe operation of such UAS and whose completion time is of reasonable length and limited duration;


You have to take an online class.


(2) include provisions that enable the operation of such UAS by individuals under the age of 16 without a certificated pilot;


It's OK if you're under 16.


(3) require UAS operators within Class B, C, D and E airspace to obtain authorization, as the Administrator may determine to be necessary within that airspace, but only after the Federal Aviation Administration has developed and implemented an automated airspace authorization system for the airspace in which the operator wants to operate; and
(4) include provisions that provide specific operational rules for UAS operating in close proximity to airports in class G airspace.


After the "automated airspace authorization system" is implemented, you have to use it.


(c) Maintaining Broad Access To UAS Technology.—When issuing rules or regulations for the operation of UAS under this section, the Administrator shall not—
(1) require the pilot or operator of the UAS to obtain or hold an airman certificate;
(2) require a practical flight examination, medical examination, or the completion of a flight training program;
(3) limit such UAS operations to pre-designated fixed locations or uncontrolled airspace; or
(4) require airworthiness certification of any UAS operated pursuant to this section.


FAA can't require special licensing, exams, certifications, etc.


(d) Collaboration.—The Administrator shall carry out this section in collaboration with industry and community-based organizations.


----------------------------------------

Tuesday, April 24, 2018

Stepper Motor: Microstepping

A coworker explains it to me:
TL;DR; is that instead of just having full forward/reverse current or not on each winding, the driver can also do things like 90%/10%, 80%/20%, 70/30, etc. current for the two windings to position the motors at angles between the full/half step positions. the actual ratios aren't quite this simplistic, and are designed to achieve something close to constant holding torque and even step spacing, but since the exact angle achieved for any winding current ratio depends on the motor design, and application, it's more or less impossible to get microstep positions that are a precise fraction of the full step angle for all motors/applications. this is mostly OK because 1) you're not making the full step positions any less accurate, 2) you're still making motor motion smoother by taking smaller steps.
a longer explanation can be found at https://hackaday.com/2016/08/29/how-accurate-is-microstepping-really/. if you want to go deeper that that, there are lots of motor controller app notes out there with all the gorey engineering details.

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