I have built and flown several APM-based quad rotors, but I am not an experienced RC person, so please be gentle with me regarding my next question. I have a feeling I'm going to start something of a controversy.
I would like to put a main power toggle switch on my quad rotor.
I have the impression the RC folks don't like main power switches because they think they will accidentally be turned on in transit in the car (maybe there are other reasons, too).
In my case, I walk outside into my backyard and I fly, so that particular issue is not an issue.
When I'm in the field, I think it's very useful, convenient, and most of all SAFE to be able to very quickly turn my quad rotor on or off with one hand.
Thus far, I have always used a plug-in style arming switch like I've shown in the attached picture. I've cut it up and soldered it into my power system. It works pretty well. But it's kind of a slow, two-handed task to insert or remove the plug. I would like something that is far quicker and easier.
So, I want to put a toggle switch on my quad rotor.
I have a feeling there are reasons people don't do this (or I would see more switches on quad rotors).
Another possible issue with a switch is that quad rotors use a 11.1v high-amp battery. So, theoretically, you need a high amp switch, which is big and bulky. On the other hand, I've used all sorts of different kinds of switches (large and small) on my land-based robots that use 11.1V high-amp LIPOs and I've never had a problem.
What are your thoughts about the idea of a toggle switch on a quad rotor?
Does anyone have a switch on their quad rotor? Or does everyone just connect and disconnect the Deans connector manually? (Which I find to be a slow, two-handed, not-very-safe task).
Does anyone have any recommendations for switches they've used or think would be worth trying?
Replies
Why not just use a spare XT60 connector as a switch? Connect the female end in series with the motor battery, solidly mount it in a place where you can easily get at it. The male part is the switch. Connect the two male terminals together. Plug the male end in to the female to enable the battery. Maybe put a large "tab" on the male end so you can pull it faster. One nice thing about these XT60s is they are quite easy to mate, one hand is good enough under most circumstances, even when not used as a "switch". Real Deans connectors are never a one-handed dis/connection job if both ends are loose, and most of the Deans clones are pretty tight too.
Alternatively, just change to XT60 connector and position your battery connector where you can get at it easily. This works and is easily a one-handed disconnect job. I like Deans too, but for some cases the better handling of the XT60 is required for safety, and really Deans are probably not the best choice for connecting the main battery to any but the smallest quads (their current rating is a bit low). Yes this might screw up using your multicopter batteries with other models, or for charging, but a couple of XT60/Deans adapters and that's done.
Not as sexy as electrical/electronic switch, but not really practical for the benefit. Typically we use a small switch to control a larger power relay, typically an automotive type for size/cost reasons. 40A or 60A relays are common and light and only a few bucks. You will discover the "issues" once you get into it. I would not bother, it is an unnecessarily "complicated" (and thus less reliable) solution to the simple requirement of quick battery disconnect.
I know there is some age to this thread , but this question of switches for the power of a quad has me baffled as well. I would love to install a small rocker switch on my dual 4s lipo operated (in parallel) Hexacopter. I hate to unplug the XT60 connectors I had on it originally , and the Deans connectors are quick to unhook, they throw sparks while hooking up . I am looking to mount an On/Off switch to take care of this . Any luck finding a decent /low cost/light weight switch?
Hi, so has anyone figured what switch is compatible with a quadrotor uav? I am also looking into this issue for my quadrotor. If anyone figured a successful solution to this problem can share it with me? Thanks
Just to offer my experience... I use a BEC to power my electronics and a switch to turn on or off the ESC/moters. I turn on the switch when the APM is up and finished booting. I turn it off for safety when handling the Quad. Though a MOSFET switch would be ideal, I have used in several Quads a Rocker style switch rated about 20A's. I have done this without any switch failures even under quick heavy loads. I have choosen switches that are all plastic outside to reduce weight and used a rocker style so it could not be turned on or off easily. As an engineer I know that the rating of a switch is not how much current it can pass, but how much it can handle actively switching current on or off. It is the turning on high current that is hard on the contacts, therefore what the contacts can actually handle when closed is much higher. This switch is never used to switch but only pass high current. The contacts may well pass double the rating. It has worked well for me and has added some safety.
HI,
I got a switch on my copter. But without a special kind of electronic high power switch behind the manual switch will solder itself and stay in on or off position.
For an electronic switch I use a: HIGH-CURRENT-PROFET BTS555 TO218
A guy in Austria is selling a setup ready for build in: http://plischka.at/BTS555-Schalter.html (in German...use Google Chrome for translations)
More information as available here: http://www.mikrokopter.com/ucwiki/ElektronischerHauptschalter (in German also).
But if you just need the pictures and the scematics than you don't need have the page translated.
CyberCrash
There are lots of discussions in the RC forums online about this. Until now, I have avoided expressing any thought. But I believe if you get a good quality switch, rated for your needs, select the right gauge wire, do a quality job on soldering and wrapping the work, it should never be a problem. Switches do wear, and poor quality switches or unrated switches can fail. But if you keep it simple, bear in mind that you are adding several (not one) new fail points (joints, stress points, resistance across connectors and length of cable, and the switch itself) then I think it should work just fine.
Really, if you cannot trust a single switch, if constructed and assembled in a quality way, then you should not put faith in the millions of switches that make up your electronics ;)
But it is another failure point. But I think that is more in your hands than it is a feature of the concept. Do shotty work, get shotty results...
Hi Robert
Im also evaluating this . Why no general switche ?
I would also find it much safer (physically at least) to be able to completely connect/disconnect/disable lipos with a single finger, from top, instead of exposing my two hands and my two forearms in a sacrificial crouched prayer (exposing sometime my face at close range)
Another time while flying really low and slow, i briefly landed, nearly stopped motors, tried to take off again and for some unknown reason it stayed there, my motors stopped responding to my radio thrust input, at 30% ; hopefully not enough to take off and fly away
I had to ask my wife to help so i could grab the hexa from top and expose the lipo cable underneath so she could disconnect it safely.
You cannot grab an hexa at arm length, motors on, from top, and then simply grab it from underneath with your other hand ; you'd certainly seevrly hurt your face and arm in the process.. and i wouldnt imagine what would happen if the quad or hexa started at that exact time to spriously wooble hard trying to compensate your movements without warning
So why not so many switches on all the rigs we see ? :)
resistance in current draw, danger ? loss of lipo perfs ?
ps : i use xt60 connectors;