Pletternberg motors
- Thread starter Droider
- Start date
Mmmm... very interesting! Funny thing is, I could use the lower Kv and the additional balancing, for sure, but the shaft mods would be a little redundant for my application. I actually like the motors mounted heli-style, through a mounting plate. The weight saving of 27g, across six motors (in my case) comes to 162g total - not greatly significant on a 7kg machine. (Just thinking aloud here)
Nevertheless - can't wait to see more detail!
Nevertheless - can't wait to see more detail!
Sure - but it's weight on or close to the axis of rotation, so it's not going to raise the inertia by much. My reason for preferring to mount the motor the other way is really my dislike of the exposed/vulnerable motor position (and the vulnerable wires) when using the DW scheme (especially for six €150+ motors). Fine (IMHO) for a smaller craft where every gram saved is valuable, but less applicable when it's a "big-mission" craft carrying an expensive payload on a paying gig. In fact, I'm designing my machine up to a target weight - I want it to weigh just under 7kg AUW. So, while I don't have "loads of room to play", I can afford to prioritise function, robustness, reliability (and even form) above lightness in certain areas.
Are these motors going to be offered for sale by you, by DW or by Plettenberg?
Are these motors going to be offered for sale by you, by DW or by Plettenberg?
Bartman
Welcome to MultiRotorForums.com!!
mounting on top of the bell instead of at the bottom puts the props closer to the mounting point and reduces the effect of run out in the shafts. mounting at the bottom with the shaft up, adding a prop adapter, then adding the prop puts the prop way up high away from the motor mount. it magnifies the runout if there is any. i think DennyR first pointed this out. makes sense, no?
Runout? On a Plettenberg? 
Seriously - yes, I believe you're right. It's another of the reasons I favour the heli-style mounting. It does tend to bring the prop closer to the arm, though - a potential disadvantage (that's hard to quantify) - arms shouldn't round anyway (and definitely not square) - an aerodynamic streamline shape is what we really need.
I'm playing the 80/20 game here - 80% of the function and performance needed is available with 20% of the effort/cost. Accessing that last 20% of function/performance costs you dearly, in time and money.
Seriously - yes, I believe you're right. It's another of the reasons I favour the heli-style mounting. It does tend to bring the prop closer to the arm, though - a potential disadvantage (that's hard to quantify) - arms shouldn't round anyway (and definitely not square) - an aerodynamic streamline shape is what we really need.
I'm playing the 80/20 game here - 80% of the function and performance needed is available with 20% of the effort/cost. Accessing that last 20% of function/performance costs you dearly, in time and money.
Bartman
Welcome to MultiRotorForums.com!!
here's an idea I've had that you might want to try.
Mount a motor to an arm and under the arm attach a free pivoting flat flag of some sort. Run the motor to about what you'd have for hover and see what angle the flag assumes. that should be your zero reference for airflow over the arm. if you then put symmetrical streamline tubing over the arm and orient it at that angle, it shouldn't generate any lift (actually yaw given the axis it would be lifting about) and be the most efficient design for an arm at the same time. it might make lift/yaw at other throttle settings but maybe the FC can accommodate that?
if you do this it must be called the Bart-Arms, that my only licensing requirement
Bart
Mount a motor to an arm and under the arm attach a free pivoting flat flag of some sort. Run the motor to about what you'd have for hover and see what angle the flag assumes. that should be your zero reference for airflow over the arm. if you then put symmetrical streamline tubing over the arm and orient it at that angle, it shouldn't generate any lift (actually yaw given the axis it would be lifting about) and be the most efficient design for an arm at the same time. it might make lift/yaw at other throttle settings but maybe the FC can accommodate that?
if you do this it must be called the Bart-Arms, that my only licensing requirement
Bart
The Bart Arms - thought that was the pub we're meeting at
Nice idea! Airflow off a prop is theoretically a spiral and I'm guessing it's precise direction will vary with throttle. Streamline tube is a bit of a headache - only available in aluminium (that I can find) unless I commission a short run on a custom mandrel at a specialist outfit. Not "good" aluminium, either - "cream cheese" model-maker's aluminium - Then there's the issue of how to clamp it, but I guess that's what CNC machines are for - a foam sleeve over a CF tube? nah! too fiddly. My guess is that the lift/yaw a streamlined arm might unintentionally make will be less of an issue that the turbulence/drag of air flowing past a square or round arm.
Nice idea! Airflow off a prop is theoretically a spiral and I'm guessing it's precise direction will vary with throttle. Streamline tube is a bit of a headache - only available in aluminium (that I can find) unless I commission a short run on a custom mandrel at a specialist outfit. Not "good" aluminium, either - "cream cheese" model-maker's aluminium
- Then there's the issue of how to clamp it, but I guess that's what CNC machines are for - a foam sleeve over a CF tube? nah! too fiddly. My guess is that the lift/yaw a streamlined arm might unintentionally make will be less of an issue that the turbulence/drag of air flowing past a square or round arm.rallymattSFP
Member
Bartman
Welcome to MultiRotorForums.com!!
The Bart Arms - thought that was the pub we're meeting at
Nice idea! Airflow off a prop is theoretically a spiral and I'm guessing it's precise direction will vary with throttle. Streamline tube is a bit of a headache - only available in aluminium (that I can find) unless I commission a short run on a custom mandrel at a specialist outfit. Not "good" aluminium, either - "cream cheese" model-maker's aluminium
actually, if you mount multiple little flags you might find the angle is slightly different at each interval along the arm. a foam airfoil would allow you to twist it to shape then you could just hard coat it with epoxy and sand it smooth.
drag over a streamline tube is a quarter of that over a round tube.
pretty funny, The Bart Arms
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BorisS
Drone Enthusiast
Anyone of you chatched on to the problems with the plettenberg motors in the german MK forum ?
http://forum.mikrokopter.de/topic-post397736.html#post397736
Seems to be that several users are having issues with the 15 series and 5s in combo with bigger props 13 14 " resulting in the ESC shutting off, mainly MK BL CTRL but also stated that this happens with the Aerodrive board and the Herkules boards.
Seems to the that the recommendation which props and voltage that should be used with the 15 series was newly stated and now 4s is recommended instead of 5s.
Not stating this because i have the orbits, just wanted to inform you guys since they are expensive motors and most of you don't speak german so this info probably wouldn't reach you.
Boris
http://forum.mikrokopter.de/topic-post397736.html#post397736
Seems to be that several users are having issues with the 15 series and 5s in combo with bigger props 13 14 " resulting in the ESC shutting off, mainly MK BL CTRL but also stated that this happens with the Aerodrive board and the Herkules boards.
Seems to the that the recommendation which props and voltage that should be used with the 15 series was newly stated and now 4s is recommended instead of 5s.
Not stating this because i have the orbits, just wanted to inform you guys since they are expensive motors and most of you don't speak german so this info probably wouldn't reach you.
Boris
redridinghood
Member
After reading the forum thru google translate I am sure a lot was lost in the translation.
So the problem is that the Orbit 15-20 draw too many amps for BL 2.0 and people are angry because the advertisement said that the motors are designed for that...
So its a BL 2.0 and other esc inadequacy and not a motor problem. Isn't it?
So the problem is that the Orbit 15-20 draw too many amps for BL 2.0 and people are angry because the advertisement said that the motors are designed for that...
So its a BL 2.0 and other esc inadequacy and not a motor problem. Isn't it?
BorisS
Drone Enthusiast
Hey Red,
I am not so sure about it. I understood that with all ESCs Aerodrive Herks MK BL CRTLs there seem to be issues with 5s and bigger props. I think best is to ask http://www.multirotorforums.com/member.php?394-achta achta, who has several sets of them and issues with them !
Boris
I am not so sure about it. I understood that with all ESCs Aerodrive Herks MK BL CRTLs there seem to be issues with 5s and bigger props. I think best is to ask http://www.multirotorforums.com/member.php?394-achta achta, who has several sets of them and issues with them !
Boris
DKTek
Member
A bit too late for me...:upset:. AEROdron only reply so far is that their techs will contact me. That was a few days ago.
Well, there are two problems:
1. You have to get the max setpoint in the BL-firmware down to 190-220, depending on the props you're using.
2. When hoovering and applying a faster throttle burst, the engines can't deliver the torque to spin up the props fast enough and the copter starts to tilt away, engines start to scream the same time -> You have to reduce the power immediately, otherwise your copter will do a roll resulting in a nice crash. We had this phenomen with 14x5 and 15x4 props, without (!) any payload: SkiJib 8, AV200 360, retracts, 2x 5s 8000, BL-Ctrl 2.0 & Aerodrive.
Imagine you have to do a faster maneuver with a heavy and expensive cam, either because of an obstacle or because you want to slow the copter down over the ground after a descent.
Don't know if this is a particular problem, or if it only concerns few people. We tried different setups since February and finally gave up.
1. You have to get the max setpoint in the BL-firmware down to 190-220, depending on the props you're using.
2. When hoovering and applying a faster throttle burst, the engines can't deliver the torque to spin up the props fast enough and the copter starts to tilt away, engines start to scream the same time -> You have to reduce the power immediately, otherwise your copter will do a roll resulting in a nice crash. We had this phenomen with 14x5 and 15x4 props, without (!) any payload: SkiJib 8, AV200 360, retracts, 2x 5s 8000, BL-Ctrl 2.0 & Aerodrive.
Imagine you have to do a faster maneuver with a heavy and expensive cam, either because of an obstacle or because you want to slow the copter down over the ground after a descent.
Don't know if this is a particular problem, or if it only concerns few people. We tried different setups since February and finally gave up.
What happened?
redridinghood
Member
Further testing required...
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