I got into Mr's about seven years ago and like many I wanted larger and more powerful machines that could lift heavy cameras. Some weird designs followed and about the only FC around at that time was MK but for reliability reasons I turned to a benchmark KK board. There were a lot of misconceptions formed about what was the best config. Okto Hexa Quad or what ever. Looking back over at least 50 different designs a pattern emerged that has stuck with me and I have a clear concept set of rules. This is just an opinion that I have formed and a lot of people wont agree but if you look in the right places the evidence is irrefutable. I now have a set of pretty advanced machines that can work safely anywhere.
I started with the Okto. Less efficient than a quad. The calculations for that are easy to understand and you can find Holgar's formula on his web site. That deficiency is often made up for by using larger props. Which as the swept area increases so does the lift efficiency. BUT the the thrust velocity decreases, it is the ratio of that value against the disturbance wind speed that creates the stability. It is also a factor of the shorter moment arm for the motor to the CofG. So next we see the Hexa. it is slightly better but not really much of an advantage. I discount redundancy issues because in this age we can get reliable components that work OK if they are set-up correctly. The next is the X8 which has better stability but will loose about 13% in thrust efficiency. Tri copters have good efficiency but weird handling and do not lend themselves well to carrying payload. So it comes down to the fact that a quad is the best solution and the smaller it is the better it will fly in a disturbed wind condition. If our models were all sub 1.5 kilo in weight and could shoot with better quality images and video than a 5D Canon we would be in a far better state than we are, with what is currently being pedaled to the masses. Just my 2 cents worth and sorry if your current thinking and investment is outside of that scenario. These are just observations that led to the creations that I am currently flying. I thought that my F1 carbon 535 was the ultimate but it was difficult to produce and as it was used primarily for pylon inspection the carbon was a risk, being a conductor of electricity. Foam board with EPP and ply/balsa are used today with a little Paxolin instead of carbon. Positive buoyancy being one advantage along with better vibration absorbance :tennis: What are your thoughts on what you fly...
I think it was about two years ago that I posted that in time we should see a Quad with a single motor and vp props. I had a design drawn up that used shaft drive but when my other half gave me that look of disapproval as she wandered into the kitchen muttering something along the lines of yet more time and money to be waisted. It got forgotten. So pleased to see that Curtis came up with his belt drive idea and more importantly he got it to work. The response time is the key to stabilisation so it will become the way to go.
As for my TDR's They have their place as a high speed vehicle that outperforms any type of MR but it can only be used in a controlled environment. As should ALL heavy lift stuff.
I started with the Okto. Less efficient than a quad. The calculations for that are easy to understand and you can find Holgar's formula on his web site. That deficiency is often made up for by using larger props. Which as the swept area increases so does the lift efficiency. BUT the the thrust velocity decreases, it is the ratio of that value against the disturbance wind speed that creates the stability. It is also a factor of the shorter moment arm for the motor to the CofG. So next we see the Hexa. it is slightly better but not really much of an advantage. I discount redundancy issues because in this age we can get reliable components that work OK if they are set-up correctly. The next is the X8 which has better stability but will loose about 13% in thrust efficiency. Tri copters have good efficiency but weird handling and do not lend themselves well to carrying payload. So it comes down to the fact that a quad is the best solution and the smaller it is the better it will fly in a disturbed wind condition. If our models were all sub 1.5 kilo in weight and could shoot with better quality images and video than a 5D Canon we would be in a far better state than we are, with what is currently being pedaled to the masses. Just my 2 cents worth and sorry if your current thinking and investment is outside of that scenario. These are just observations that led to the creations that I am currently flying. I thought that my F1 carbon 535 was the ultimate but it was difficult to produce and as it was used primarily for pylon inspection the carbon was a risk, being a conductor of electricity. Foam board with EPP and ply/balsa are used today with a little Paxolin instead of carbon. Positive buoyancy being one advantage along with better vibration absorbance :tennis: What are your thoughts on what you fly...
I think it was about two years ago that I posted that in time we should see a Quad with a single motor and vp props. I had a design drawn up that used shaft drive but when my other half gave me that look of disapproval as she wandered into the kitchen muttering something along the lines of yet more time and money to be waisted. It got forgotten. So pleased to see that Curtis came up with his belt drive idea and more importantly he got it to work. The response time is the key to stabilisation so it will become the way to go.
As for my TDR's They have their place as a high speed vehicle that outperforms any type of MR but it can only be used in a controlled environment. As should ALL heavy lift stuff.
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