Servers by jDrones

I can arm and disarm but engines never stop?


(ahmet omer ozgen) #1

Hello. I have successfuly calibrated the GPS and the others. Assembled the boat. Set the differential thrust. I simply want to make engines stop when the right stick is at zero.

Things i did.
I just connect the turnigy 9x(mode 1) to Pixhawk(it supports pwm without encoder) directly( i didnt mix any channels on the RC transmitter)
I just connected the ESC’s(cut the 5v+ bec line) to pixhawk.

pix hawk is connected to the Mission planer via telemetry.

everything works and just this by itself made me doubt everything. the boat is in stationary mode(on desk). it says bad ahrs (maybe because im at home?)

Well, when i put the steering (right) stick to right for 2 secs, the engines start running(quite fast). I even saw soem sparks for an instances above the motors. Then i just turn of the ESC’s.

It is in manual mode but why the boat does start with a quite fast paced pulse? I want it to be at zero speed. Since this is the manual mode?

I want to test the transmitter. If i go to my pool it will just crash at a quite fast pace. (twin 12V 540’s)

Please help me :frowning: :frowning:

I need to test it in manual mode and see how skid steer works. The Boat is around 5KG and 92cm. It wont go fast but i actually want it to run very slow tho.

This is the boat!



.


(David Boulanger) #2

What do you mean by having the motors stopped when the right stick is zero? What do you consider zero?


(ahmet omer ozgen) #3

Hello,

Sorry for the lack of terminology. When The throttle stick at the down position (min.), motors still run. Is there a way to configure it to start from no pulse (0 percent rotation) to gradually increase the volt?

Btw i wired the motors normally (to red wire to +). I suppose the parameters automatically makes one engine go in reverse(port side) (cw). Starboard in ccw?

I simply want to figure out to assign flight modes in 3 way selector of transmitter. And want to see no movement when the throttle stick is at minimum (down)

Thank you


(ahmet omer ozgen) #4

Rc transmitter shows the device is a copper maybe i should select the plane?

Thanks


(David Boulanger) #5

Sounds like a speed controller issue maybe. If your throttle stick is all the way down it should be in full reverse. I’m not real familiar with setting up parameters for a brushed motor.


(ahmet omer ozgen) #6

Well i didn’t know that. :flushed: So center means no throttle. Btw if the boat goes in reverse is there a chance that my props will fall off?

Because while testing earlier i switched the props. When i pushed forward (stick), boat went backwards and props unscrewed themselves…

But of course i fixed them. And they are in correct orientation. But now since there is a complete different setup(new esc pix hawk controller etc), would the screws undo themselves?

I now im a total newbie. But this is my first rc project :grin:

Your help is greatly appreciated


(Dave) #7

You set it up for skid steer then center throttle is neutral. If the props spin off then clearly it wasn’t designed to run in reverse. The sparks may be an indication the motor brushes didn’t like reverse either although most brushed motors run in reverse no problem.


(ahmet omer ozgen) #8

yes this makes too much sense. I didn’t know this. But i didnt know it and i armed the boat on the with the stick all the way down. Which is too much amp and volt for the motors suddenly. I saw the spark for a second tho at the back. The ESC’s are pretty responsive.

I thought it was a config. error. but clearly it’s my lack of knowledge. The whole RC transmitter is a mistery for me

thank you. I’ll test stuff again when I’m home.

Dave noreply@ardupilot.org, 16 Nis 2019 Sal, 15:59 tarihinde şunu yazdı:


(Dave) #9

I’m not as familiar with skid steer but you may be able to setup a mix on your transmitter for throttle stick low being neutral and neither motor would reverse just supply differential forward thrust. You would have no reverse then and it would not zero turn. This sounds like the way the stock boat was setup. Did you run it stock?

On my rover, which is not skid steer, I have this setup on the throttle because I do not like center throttle neutral with forward/reverse stick high/low. I use a switch to select reverse kind of like a gear shift lever.


(ahmet omer ozgen) #10

Thank you.

I really don’t know how to do it. Esc’s are directly plugged into the pix hawk.

Would it work? The transmitter looks complicated.

When i bought the boat it came with 1 channel transmitter.

Yes the settings are stock. (turnigy)

I’ll dig that this evening.

Thanks


(Dave) #11

What Turnigy radio do you have? It’s pretty simple to setup this mix on the throttle channel. 50% weight and 50% offset will do it.

Also, setup a switch for arming. A lot easier to manage than the stick arming and there isn’t the danger with a boat that there is with switch arming a flying craft. Worst case you go for a swim :grinning:


(ahmet omer ozgen) #12

Turnigy 9x https://hobbyking.com/en_us/turnigy-9x-9ch-transmitter-w-module-ia8-receiver-mode-2-afdhs-2a-system.html

Mode 1(right stick is free to move)

But im not sure about the software version


(Dave) #13

Well now I’m not sure that changing the throttle stick channel mix will work as expected for a skid steer configuration. But you could try it on that radio by changing the Trim and Endpoint settings so low throttle stick is at 50% and high throttle stick is 100%. Check with Mission Planner on the radio calibration page if your settings are producing this before running the boat.

Or maybe you can just leave it as is and come up with a way to prevent the props from spinning off in reverse. How are they attached to the propshaft?


(ahmet omer ozgen) #14

You just turn them. But each one turns in a different direction. You must hold the shaft while putting the prop


(Dave) #15

Ah, self tightening. That doesn’t help matters any, not sure how you will be able to prevent the props from spinning off in reverse. Maybe you will have to replace the propshafts with something more adaptable.

What ESC’s do you have? Some ECS’s for cars can be configured for Forward and Brake only (no reverse) which could work.


(ahmet omer ozgen) #16

Changing the prop shafts could work i guess.

The esc’s are https://www.promodelhobby.com/urun/fircali-80a-320a-rc-esc-7-2v-16v-fanli-2s-4s

Nice thing is i can always add 2 more motors with the same configuration as a boost :joy:

I got home. It doesn’t arm now. :sob: Did some forced arms. It doesn’t move on center.

Both engines run ccw. I will make the port side wired in different ways (+, -).

Do i really need reverse? It could be really useful. My biggest issue is configuration. It is hard. I can’t do it well.

Keep saying bad ahrs…

Gps doesn’t fix. İ need to recalibrate stuff. I’ll do it tomorrow on the balcony.


(Dave) #17

I don;t think those ESC’s can be configured for Forward/Brake. This is usually either done by jumpers on the ESC or thru a programming device. But in the description it simply states " * Movements: Forward, Reverse and Brake" So you will have to do this thru the radio.

No, you don’t need reverse and in fact that boat was not built to run in reverse. But unless you want to leave your props at the bottom of the lake by hitting reverse accidentally I think you will want to set it up so It can’t run in reverse at all.


(ahmet omer ozgen) #18

That’s correct! So there is no way to block reverse thru the mission planner?

I will figure out the radio, hopefully.

This one doesn’t have the jumpers. But when it’s armed it makes some beeps.

Can you elaborate on the BAD AHRS warning?

Is there any special way or tricks to calibrate the accel and compasses.

How will i calibrate the GPS tho?

in a week I’m supposed to make this thing run in auto mode. I will add the lidar soon. I think stop function will be better than the going around.

your help is extremely appreciated.

It is kinda sad to not have ready to run parameters.


(Dave) #19

Block reverse from Mission Planner. I’m wondering if this could be accomplished with setting the Servo max/Min/Trim settings. I’ll try something out on the bench.

Bad AHRS could just be a poor GPS reception indoors. Take it outside and see if it clears.

GPS is not calibrated. Accels can be done with the Pixhwawk on the bench in 3-axis then when it’s in the boat level it and then use the 1 axis calibration. Compass cal just spin the boar around a few axis using a long USB cable.


(David Boulanger) #20

I think you can use servo min and max setting to not reverse. Not sure how that would do with differential thrust though.