Curiosity nearly killed my cat......

[Jammey Dodger]

Last weekend I was intrigued to see what happens to solo when the battery depletes fully....

Sat in the garden, set the return home to launch site, set the height to zero meters and thought what's the worst could happen.

GPS lock, lift off... Solo sat there about 1m-2m off the ground for about 15 or so minutes.

As I watched the battery slowly deplete, I think it tried to return home but I cancelled it to see what the bird would do at 0%... Still hovering in the back yard, where it took off, battery was flashing 0% and still hovering nicely....

As I thought how very uninteresting and I'll land now, all of a sudden, the solo went up to say 10m and shot 10m horizontally away from the launch site..... With this I lost all response on the controls.... It sat there for a few seconds then dropped like a stone.......

Despite there being no damage, what shocked me was the return to home height being set to zero meters but the solo still climbed to approx 10m and lost response.....

Silly question.....is this normal for the solo to do what it wants when you loose battery power?

 

[Solo Keith]

So what happened to the cat?

 

[User Name]

So what happened to the cat?

We won't know until we open the box. Until then, the cat is in a superposition of alive and dead.

Regarding the test, I would definitely submit a ticket to 3DR, as it sure seems to be some type of bug in the RTL code. Perhaps some combination of already being at the home position and RTL altitude confused it.

At some point, there was a change in the RTL altitude which automatically reduced it from what the user set based on the distance from the home point. I understand the reasoning behind this - no point climbing to a set altitude of 150 feet if you're only 30 feet or so from your home point. On the other hand, I'm a proponent of maximum predictability - I don't like to be surprised and have to decide in a split second or two why it's doing whatever it's doing and whether or not it'll run into problems in doing so. I think it's better for an operator to have to keep one thing in mind (RTL altitude), than be surprised.

 

[Pedals2Paddles]

Were you watching the voltage? If not, you probably did irreversible damage to the battery, which was not very wise. Can you download and post the log files? We can probably figure out what it was trying to do from the logs. My inclination is the RTL kicked in for one of numerous reasons, and the GPS home position or current position was not accurate. Especially if you manually set the home position yourself, which it sounds like you did.

 

[LuvMyTJ]

Were you watching the voltage? If not, you probably did irreversible damage to the battery, which was not very wise. Can you download and post the log files? We can probably figure out what it was trying to do from the logs. My inclination is the RTL kicked in for one of numerous reasons, and the GPS home position or current position was not accurate. Especially if you manually set the home position yourself, which it sounds like you did.

I agree. The OP should do some research on how lipo's work and their care so as to avoid damage and/or fires. They are not your average household alkaline.

 

[Maddog]

This might be useful:
Electric RC info, how-tos and such - TJinTech

Everything you ever wanted to know about lipos.

 

[Maddog]

Last weekend I was intrigued to see what happens to solo when the battery depletes fully....

Sat in the garden, set the return home to launch site, set the height to zero meters and thought what's the worst could happen.

GPS lock, lift off... Solo sat there about 1m-2m off the ground for about 15 or so minutes.

As I watched the battery slowly deplete, I think it tried to return home but I cancelled it to see what the bird would do at 0%... Still hovering in the back yard, where it took off, battery was flashing 0% and still hovering nicely....

As I thought how very uninteresting and I'll land now, all of a sudden, the solo went up to say 10m and shot 10m horizontally away from the launch site..... With this I lost all response on the controls.... It sat there for a few seconds then dropped like a stone.......

Despite there being no damage, what shocked me was the return to home height being set to zero meters but the solo still climbed to approx 10m and lost response.....

Silly question.....is this normal for the solo to do what it wants when you loose battery power?

From the Solo user manual page 33, under Return To Land:

When a call to Return Home is triggered and Solo is flying above the Return Home Altitude (default: 25m), Solo:

1. Climbs 10m
   
   
2. Traverses to the Home Position
   
   
3. Descends and lands
   
   If you set RTL altitude to 0 this might explain the climb. Don't know about the horizontal shift.