Hack (Mod?) for a Safer Solo near People

[John Githens]

There's a saying about "two kinds of projects", something like: (a) the project starts with a Design, then the parts are gathered and assembled; (b) the project starts with stuff on hand, then some of the stuff is assembled into some thing. My recent project was a bit of both.

My goal was to have the safest Solo to operate near (not directly above) people for slow-and-low filming. I have lost some sleep worrying about slicing a face, eye, hand or other body part in the event of loss of GNSS lock, an operator failure, or an equipment failure. Liability insurance won't prevent the suffering related to harming a person or pet. Unlike some who like to be stealthy, I want my flying robots to be very visible to any Participant, and to be easily seen and avoided by anyone else near by. Even those two dogs I have met who seem to think a Solo coming in to land looks like a Frisbee...

I had a hunch that a stock Solo could be the basis for a safer Solo, if it was partially disassembled and reassembled on a PEX frame I had from HooperFly. I also had some nice Cobra 2221/16 940KV motors and APC props on hand from previous DIY projects. Turns out that this hack/mod can be done, and the result is safer and quieter than any of my other Solos. However this is not an easy, quick project.

Of course there were a few tradeoffs:
(1) The gimbal must be aimed down a few degrees to avoid the PEX frame in the shot (I use Peau 3.97mm and 3.37mm lenses).
(2) There was a net increase in All-Up Weight (AUW) from adding the PEX frame, hardware and slightly heavier Cobra motors. However safer operation was more important than losing some flight duration. (comments and videos later in this thread)
(3) In this configuration you lose the ability to easily swap out payload items. This build was customized for the Solo Gimbal.
(4) It took time to find a way to securely attach legs to the PEX frame in this configuration (note the inverted motors and props). The upside: Nothing impedes the prop wash. No vibrations from prop wash over the frame.
(5) Not so easy to reach the Pair hole with a paper clip when upgrading firmware! I added an access hole to the HooperFly frame plate which is bolted to the underside of the Solo frame.

I won't write a book about this project, however you can see the attached, numbered images to get clues about some of the assembly challenges.

 

[XevetS]

Very nicely implemented, Now for some flight footage! Please...oh and thanks in advance.

 

[Maddog]

Let us know how that impacts flight time, camera vibration, etc.

 

[Pedals2Paddles]

I don't think that's going to fly. Or at least not very long after lifting off. One screw holding each hoop on with zipties. It has no structural integrity. The motors will flop that to pieces in the air nearly immediately.

 

[John Githens]

There's a saying about "two kinds of projects", something like: (a) the project starts with a Design, then the parts are gathered and assembled; (b) the project starts with stuff on hand, then some of the stuff is assembled into some thing. My recent project was a bit of both.

My goal was to have the safest Solo to operate near (not directly above) people for slow-and-low filming. I have lost some sleep worrying about slicing a face, eye, hand or other body part in the event of loss of GNSS lock, an operator failure, or an equipment failure. Liability insurance won't prevent the suffering related to harming a person or pet. Unlike some who like to be stealthy, I want my flying robots to be very visible to any Participant, and to be easily seen and avoided by anyone else near by. Even those two dogs I have met who seem to think a Solo coming in to land looks like a Frisbee...

I had a hunch that a stock Solo could be the basis for a safer Solo, if it was partially disassembled and reassembled on a PEX frame I had from HooperFly. I also had some nice Cobra 2221/16 940KV motors and APC props on hand from previous DIY projects. Turns out that this hack/mod can be done, and the result is safer and quieter than any of my other Solos. However this is not an easy, quick project.

Of course there were a few tradeoffs:
(1) the gimbal must be aimed down a few degrees to avoid the PEX frame in the shot (I use Peau 3.97mm and 3.37mm lenses).
(2) there was a net increase in All-Up Weight (AUW) from adding the PEX frame, hardware and slightly heavier Cobra motors. However safer operation was more important than losing some flight duration.
(3) in this configuration you lose the ability to easily swap out payload items. This build was customized for the Solo Gimbal.
(4) it took time to find a way to securely attach legs to the PEX frame in this configuration (note the inverted motors and props). The upside: Nothing impedes the prop wash. No vibrations from prop wash over the frame. (No, I have not done a flight duration test.)

I won't write a book about this project, however you can see the attached, numbered images to get clues about some of the assembly challenges.

View attachment 7537 View attachment 7538 View attachment 7540 View attachment 7541 View attachment 7542 View attachment 7543 View attachment 7544 View attachment 7545

Update with flight test results today:
43 degrees F. 6-8 knot wind (est.).
Almost new, freshly charged battery.
Battery down to 50% at about 6 minutes. 25% at about 8 minutes.
At 60 feet the mRo GNSS module locked to a new record (for me) of 29 sats.
Easy launch. No Solo issues with bounce on landing.
GoPro Hero 4 Black with Peau 3.37mm lens.
Gimbal angle needs to be at least 75 degrees to avoid frame in view. More if in stronger wind.
Quickly post-processed with PowerDirector15, only for color and sharpness.
>Here< is a link to a short video from the GoPro.
>Here< is a link to a short video from my hand-held iPhone 5S.
As for concerns about the PEX frame from HooperFly, I have had zero problems with losing motors or zipties on two quad builds and many hours of flight time.

 

[Pedals2Paddles]

Well then. In the wise words of renowned robotics scientist Ben Jabituya, "I am standing here beside myself".

 

[J0S0L0]

There's a saying about "two kinds of projects", something like: (a) the project starts with a Design, then the parts are gathered and assembled; (b) the project starts with stuff on hand, then some of the stuff is assembled into some thing. My recent project was a bit of both.

My goal was to have the safest Solo to operate near (not directly above) people for slow-and-low filming. Even those two dogs I have met who seem to think a Solo coming in to land looks like a Frisbee...

View attachment 7545

I give you an A for all your time and effort, and those bigger motors are making me envious..

I've had dogs come out of nowhere in public places, and it turns into a hairy situation.

Although the leash laws prevent liability, I hate all the drama...

 

[John Githens]

I give you an A for all your time and effort, and those bigger motors are making me envious..

I've had dogs come out of nowhere in public places, and it turns into a hairy situation.

Although the leash laws prevent liability, I hate all the drama...

Twice I have been on a beach where some walkers don't leash their dogs. I was bringing a Solo in for a landing and up runs this barking dog. Back up I send it, hoping the owner and pet move on before the battery gets too low. For the record: I like most dogs. A related story is the 5 or 6 year old boy that ran up to hang out under the Solo as I was trying to land. Fortunately I was able to get his attention and wave him away. I have found that many people have yet to see any quadcopter in use. Lots of curiosity, and usually positive interest. But not much awareness of the danger of spinning props on powerful motors.

 

[Maddog]

Twice I have been on a beach where some walkers don't leash their dogs. I was bringing a Solo in for a landing and up runs this barking dog. Back up I send it, hoping the owner and pet move on before the battery gets too low. For the record: I like most dogs. A related story is the 5 or 6 year old boy that ran up to hang out under the Solo as I was trying to land. Fortunately I was able to get his attention and wave him away. I have found that many people have yet to see any quadcopter in use. Lots of curiosity, and usually positive interest. But not much awareness of the danger of spinning props on powerful motors.

There's nothin' you can do about stupid.

 

[John Githens]

Update with flight test results today:
43 degrees F. 6-8 knot wind (est.).
Almost new, freshly charged battery.
Battery down to 50% at about 6 minutes. 25% at about 8 minutes.
At 60 feet the mRo GNSS module locked to a new record (for me) of 29 sats.
Easy launch. No Solo issues with bounce on landing.
GoPro Hero 4 Black with Peau 3.37mm lens.
Gimbal angle needs to be at least 75 degrees to avoid frame in view. More if in stronger wind.
Quickly post-processed with PowerDirector15, only for color and sharpness.
>Here< is a link to a short video from the GoPro.
>Here< is a link to a short video from my hand-held iPhone 5S.
As for concerns about the PEX frame from HooperFly, I have had zero problems with losing motors or zipties on two quad builds and many hours of flight time.

I've worked with a couple of HooperFly frame designs, using versions of Pixhawk. Amazingly rugged, in different ways than a Solo frame is rugged (too bad the Solo Gimbal is not so rugged). Readers of this thread might like to visit HooperFly on Instagram, including this post. (If you're interested in a recent example of computer vision tracking of three small UAVs, see this post.)

 

[John Githens]

For anyone who wants to do this hack/mod for more safety:

a) The weight penalty is about 600 grams (or less, if you use lighter motors than the Cobra 2221/16 that I had on hand, which are 88 grams each per the manufacturer's specification sheet). A stock 3DR Solo motor, less the ESC board and screws, weighs about 64 grams.

b) I used APC 10x4.5 props, which are well matched to these Cobra motors for performance. Two each of 10x4.5MR(ST2A) and 10x4.5MRP(ST2A).