swansont Posted July 30, 2015 Posted July 30, 2015 Always running out when it's inconvenient. Expensive . Key word: inconvenient. It's a "first-world problem". You haven't said anything to convince me that lugging around an antenna is more convenient, and it's not like this system will do away with the need for batteries. And expensive? You've mentioned your system will be free but haven't explained that at all. This will be provided by the space-solar elves? You want power-on-the-go for small electronics? Work on a kinetic charger that generates power from you moving around. (This is something that's actually in development)
Mike Smith Cosmos Posted July 30, 2015 Author Posted July 30, 2015 (edited) Key word: inconvenient. It's a "first-world problem". You haven't said anything to convince me that lugging around an antenna is more convenient, and it's not like this system will do away with the need for batteries. And expensive? You've mentioned your system will be free but haven't explained that at all. This will be provided by the space-solar elves? You want power-on-the-go for small electronics? Work on a kinetic charger that generates power from you moving around. (This is something that's actually in development) .Antennas can be very creative , nowadays. The big coil was just a bit of humour ! The 'free issue ' is a bit like wi fi is going , with data , so with energy . Consumers ( Home owners and Industry ) subsidise the common utilities. Personal carriers could similarly take on a new industrial development from simple beginnings. Mike Edited July 30, 2015 by Mike Smith Cosmos
swansont Posted July 30, 2015 Posted July 30, 2015 . Antennas can be very creative , nowadays. The big coil was just a bit of humour ! Humour as an addendum to technical discussion is good. As a replacement for it, not so much. The 'free issue ' is a bit like wi fi is going , with data , so with energy . Consumers ( Home owners and Industry ) subsidise the common utilities. More "analysis-free" commentary. "free" wi-fi isn't free. It's just rolled into the cost of the other things you are buying at the establishment that offers it. If it gets you into Starbucks to buy one of their drinks, it's a money-maker, like advertising. But ultimately the customer pays for it. Personal carriers could similarly take on a new industrial development from simple beginnings. image.jpg Mike These don't suddenly become possible with low power being available. If we don't have them already, they aren't going to sprout up like mushrooms with this system
Mike Smith Cosmos Posted July 30, 2015 Author Posted July 30, 2015 (edited) Swansont said Quote " Humour as an addendum to technical discussion is good. As a replacement for it, not so much." Reply :- See this small antenna . Long wave . Few inches long Swansont said Quote " More "analysis-free" commentary. "free" wi-fi isn't free. It's just rolled into the cost of the other things you are buying at the establishment that offers it. If it gets you into Starbucks to buy one of their drinks, it's a money-maker, like advertising. But ultimately the customer pays for it. Reply : true . But this is the sensible way to operate the system . Mike Smith Cosmos, on 30 Jul 2015 - 2:28 PM, said: Personal carriers could similarly take on a new industrial development from simple beginnings. Swansont said These ( personal fliers ) don't suddenly become possible with low power being available. If we don't have them already, they aren't going to sprout up like mushrooms with this system. Mike said " It's the chicken and egg syndrome " put them there both together! " I would just love nothing better , than in my dotage 'to develop a personal flying machine ' , that could work off continuous 300 watts . Let me at it .! I rescued a hang 30 ft glider from from a skip once . Never did get to fly it . Probably the bungee jump put me off. Until then the personal vehicles will have to remain earth bound ! But let's just step up a few 10's of feet , and enjoy cruising gently ,the third dimension . The staff in our cafe made an input as to which way they would prefer to be ' orientated ' Me ( leaning forward ) , another leaning backwards, another in the superman position. I have just designed the shape of the helium tank . Just the drive and we are ready ! Drive in principle . ( brown ) Antenna in principle ( red ) A whole concept design In place for a prototype / model to be built and tested . That's what you said was needed. This together with a long wave transmission of energy , and the system in principle can be built as a model prototype system , for testing . Mike Edited July 30, 2015 by Mike Smith Cosmos
swansont Posted July 30, 2015 Posted July 30, 2015 " I would just love nothing better , than in my dotage 'to develop a personal flying machine ' , that could work off continuous 300 watts . Let me at it .! Start with the physics that would let you fly around using 300W. Upwards of 1 kN minimum thrust just to hover. (for ~100 kg person+device) Art without the requisite science and/or engineering is not design. It's art. See this small antenna . Long wave . Few inches long image.jpg How much power can it receive from a 100 W/m^2 signal? Conversely, how many of them do you need to get 100 W from that signal?
Mike Smith Cosmos Posted July 30, 2015 Author Posted July 30, 2015 Start with the physics that would let you fly around using 300W. Upwards of 1 kN minimum thrust just to hover. (for ~100 kg person+device) Art without the requisite science and/or engineering is not design. It's art. How much power can it receive from a 100 W/m^2 signal? Conversely, how many of them do you need to get 100 W from that signal? Yes but it's FUNCTION and FORM . Not FUNCTION without Form nor FORM without Function , So surely we. Need both FUNCTION and FORM namely PHYSICS and ART . Not PHYSICS or ART . but FUNCTION and FORM Mike
swansont Posted July 30, 2015 Posted July 30, 2015 Yes but it's FUNCTION and FORM . Not FUNCTION without Form nor FORM without Function , So surely we. Need both FUNCTION and FORM namely PHYSICS and ART . Not PHYSICS or ART . but FUNCTION and FORM Mike But this is a science forum, and you are ignoring the science completely.
Mike Smith Cosmos Posted July 30, 2015 Author Posted July 30, 2015 (edited) But this is a science forum, and you are ignoring the science completely.No , I have a lot of experience of communications at the science end . FUNCTION But I am deliberately starting with the FORM as this is a user project , at least this low power aspect, where the user is king and his requirements are uppermost . . All too often the science leads ( as with the growth of computers ) it is only now after 40 years is the user king . For those 40 years , software writers and hardware designers, cloaked the systems in scientific mystery . ( perhaps not deliberately ) If we can start this time with what the user would ideally wish for , we can then see if science ( by Function ) is able to provide what the FORM USER would Like by ideal . I count myself fortunate that I have a "boot in both camps " , if I have that quotation correct( sounds a bit odd ) MIKE Edited July 30, 2015 by Mike Smith Cosmos
swansont Posted July 30, 2015 Posted July 30, 2015 No , I have a lot of experience of communications at the science end . FUNCTION But I am deliberately starting with the FORM as this is a user project , at least this low power aspect, where the user is king and his requirements are uppermost . . All too often the science leads ( as with the growth of computers ) it is only now after 40 years is the user king . For those 40 years , software writers and hardware designers, cloaked the systems in scientific mystery . ( perhaps not deliberately ) If we can start this time with what the user would ideally wish for , we can then see if science ( by Function ) is able to provide what the FORM USER would Like by ideal . I count myself fortunate that I have a "boot in both camps " , if I have that quotation correct( sounds a bit odd ) MIKE I build atomic clocks, so I have been in both camps, too. If it doesn't work, it doesn't matter what the form is. How much can you lift, and in what form, with 300W?
Mike Smith Cosmos Posted July 31, 2015 Author Posted July 31, 2015 (edited) I build atomic clocks, so I have been in both camps, too. If it doesn't work, it doesn't matter what the form is. How much can you lift, and in what form, with 300W?. It does not matter , surely ? Because I can use a lifting system that has nothing to do with the 300 watts , namely a helium balloon . Now I am risen the 300 watts can be used, (should it be needed) for propulsion through the atmosphere, namely against air resistance that will be a , definable, calculable quantity . Which I must admit , I do not know the aerodynamic formulae for . However , it will be , what it will be . Very similar to current automotive equations ( without the tyre resistance) as there will be no contact with the ground. I can remember from high school being told by our physics teacher to my utter amazement , that all the petrol was doing , going down the road , was overcoming air and tyre resistance and other internal resistances ! I never got over that shock! I imagine , we will have to put up with a rather ' sedate ' pace . But that I imagine will be good for our demeanour ? Here is someone else's design , I was hoping for something with less contraption being hauled aloft . The (lift is free) , the ' watts ' can be used for forward horizontal propulsion , whatever is available ! Mike Edited July 31, 2015 by Mike Smith Cosmos
swansont Posted July 31, 2015 Posted July 31, 2015 . It does not matter , surely ? Because I can use a lifting system that has nothing to do with the 300 watts , namely a helium balloon . So then the lifting is being done by something else. You don't need EM power transmission to make helium work. We already have helium transport. It is not used widely. Do you really think that the one thing holding us back is the availability of less than half a hp?
Mike Smith Cosmos Posted July 31, 2015 Author Posted July 31, 2015 (edited) So then the lifting is being done by something else. You don't need EM power transmission to make helium work. We already have helium transport. It is not used widely. Do you really think that the one thing holding us back is the availability of less than half a hp?No, but we are living in an electrical society . I only picked personal transport as an example . My wife has the car , I either go by motor scooter or more recently I bought a Smart Car , so me and the Jack Russel can go easily places to paint or whatever. You could walk everywhere I suppose . Horses are gone or impractical . The peak oil , will arrive one of these days , or some other related hic-up with supply. We had one a few years ago ( can't remember why ) but everything nearly ground to a halt. So I am trying to think ahead . Remember it is 100 watts per square meter, so every 5.square meters approx , we get a 1 horse power motor. Let's for a moment think of some public transport flying bus with a 100 sq M footprint 5m x 20 m . Will give us a 20 horse power motor . Quite adequate to push a bus load of sightseer's to the next stopping tower . Then I could think about the , lawn mower , the portable live band, the outside camping , food stall , pond fountain, I pad , pizza oven , stadium lights , TV, radio , motor boat, the list is endless when you think of outside use of electrical devices. Also portable ones inside the home . Mike Flying bus :- Edited July 31, 2015 by Mike Smith Cosmos
swansont Posted July 31, 2015 Posted July 31, 2015 Your staunch refusal to incorporate any science in the conversation is something I find exceedingly annoying. So I'll do it. The lifting power of Helium is about a gram per liter at room temperature, or 1 kg per m^2. 5m diameter x 20m long (smaller, if tapered as in your picture) is ~400 m^3. So you can lift 4 or 5 people, if they don't have powered flight. Add motors and propellers, and you can move 3 or 4 people around. 1 is the pilot. That's not a bus, that's a taxi. A slow taxi. How slow is a matter of further analysis. How little wind will it take to ground this, because it can't overcome to breeze? Let's for a moment think of some public transport flying bus with a 100 sq M footprint 5m x 20 m . Will give us a 20 horse power motor . Quite adequate to push a bus load of sightseer's to the next stopping tower . Prove to me it's adequate.
Mike Smith Cosmos Posted July 31, 2015 Author Posted July 31, 2015 (edited) Your staunch refusal to incorporate any science in the conversation is something I find exceedingly annoying. So I'll do it. The lifting power of Helium is about a gram per liter at room temperature, or 1 kg per m^2. 5m diameter x 20m long (smaller, if tapered as in your picture) is ~400 m^3. So you can lift 4 or 5 people, if they don't have powered flight. Add motors and propellers, and you can move 3 or 4 people around. 1 is the pilot. That's not a bus, that's a taxi. A slow taxi. How slow is a matter of further analysis. How little wind will it take to ground this, because it can't overcome to breeze? Prove to me it's adequate. Well we can make the balloon as large as you like to provide the lift. This is what happened in the days around the beginning of the 20 th century . Unfortunately they used Hydrogen without adequate safety standards , the hindenberge disaster where it caught fire brought balloon public transport to a halt. Prior to that people were cruising all over the world Link :- https://en.m.wikipedia.org/wiki/Airship . . Mike Edited July 31, 2015 by Mike Smith Cosmos
swansont Posted July 31, 2015 Posted July 31, 2015 No analysis. No surprise. Bigger means more drag. Also more expensive. Drag is 1/2 p v^2 cd A, and the power at a constant force is Fv the density of air is p = 1.2 kg/m^3 and the drag coefficient of a sphere is 0.5, so let's start with that. P = 1/2 p v^3 cd A To go 1 m/s, you need 1.875 watts. So 300 watts lets you go 5.5 m/s. 20 km/hr, if there's no wind. (also, I forgot the weight of the antenna you need to pick up the 300 w in my previous discussion)
Mike Smith Cosmos Posted July 31, 2015 Author Posted July 31, 2015 (edited) No analysis. No surprise. Bigger means more drag. Also more expensive. Drag is 1/2 p v^2 cd A, and the power at a constant force is Fv the density of air is p = 1.2 kg/m^3 and the drag coefficient of a sphere is 0.5, so let's start with that. P = 1/2 p v^3 cd A To go 1 m/s, you need 1.875 watts. So 300 watts lets you go 5.5 m/s. 20 km/hr, if there's no wind. (also, I forgot the weight of the antenna you need to pick up the 300 w in my previous discussion) . -- Designers and Engineers Fix things . -- If it's too heavy they use lighter materials . If it's not strong enough they use modern materials. What with Carbon fibres , plastics and a host of new materials I am sure we will make this work . I can't even get my loaf out of a plastic mag without crushing the bread , because the plastic bag is so,so strong you can't even tear it apart. And if I pick up a polystyrene packing , it's so light , and crumbly it sticks to my fingers . Engineers fix things Mike Edited July 31, 2015 by Mike Smith Cosmos
swansont Posted July 31, 2015 Posted July 31, 2015 Engineers fix things Engineers use engineering to fix things (i.e. models, and math). Not hand-waving. No amount of engineering is going to "fix" a violation of conservation of energy.
Phi for All Posted July 31, 2015 Posted July 31, 2015 ! Moderator Note Mike, there isn't enough rigour in the argument, "I"m pretty sure an engineer will probably find a way, maybe." More science, please.
Mike Smith Cosmos Posted July 31, 2015 Author Posted July 31, 2015 (edited) Well if you want engineering rigour, I am not expert enough on aero dynamics to give you spectacular science in aero dynamics. I can do a scientific experiment with a flying model when I next see those Helium party balloons for sale . By building a small scale airship/pod with scaled down passenger and small electric motor with fan blade. Also I will build a low power long wave transmitter . Send a partially focused beam of long wave in direction of model . Receive with a ferrite rod antenna . Drive the motor , which drives the blade. The helium balloon and supported pontoon pod combination , should move off in a horizontal direction . Thus the prototype can be seen ,as proof of concept Is that rigorous enough science at the model level , to prove that it is worth scaling up to a larger version . ( Possibly carrying my Jack Russell . though I cannot be held to this last idea ) If you want me to do lots of sums ( I am not sure if I know where my slide rule is ? ) Mike Edited July 31, 2015 by Mike Smith Cosmos
swansont Posted July 31, 2015 Posted July 31, 2015 Well if you want engineering rigour, I am not expert enough on aero dynamics to give you spectacular science in aero dynamics. The problem is that you are not even doing an order-of-magnitude analysis. You throw out an idea and I shoot it down, and you reply with "scale it up". That analysis — that science — needs to be done as part of the proposal.
Mike Smith Cosmos Posted July 31, 2015 Author Posted July 31, 2015 (edited) The problem is that you are not even doing an order-of-magnitude analysis. You throw out an idea and I shoot it down, and you reply with "scale it up". That analysis that science needs to be done as part of the proposal. Yes well I understand what you are saying . Is my proposed project of sufficient rigour, to satisfy your requirements? In other words , if I produce a working model with reasonably predictable results , even if not 100% achievement , acceptable as a rigorous scientific experiment ? Mike Edited July 31, 2015 by Mike Smith Cosmos
Mordred Posted July 31, 2015 Posted July 31, 2015 In other words , if I produce a working model with reasonably predictable results , even if not 100% achievement , acceptable as a rigorous scientific experiment ? Mike Yes we have numerous examples where predictions indicate possibilities beyond our technology
swansont Posted July 31, 2015 Posted July 31, 2015 Yes well I understand what you are saying . Is my proposed project of sufficient rigour, to satisfy your requirements? In other words , if I produce a working model with reasonably predictable results , even if not 100% achievement , acceptable as a rigorous scientific experiment ? Mike Do the test, and let's see what you get.
Mike Smith Cosmos Posted July 31, 2015 Author Posted July 31, 2015 Do the test, and let's see what you get.Just got a few components together . Threw most away 4 months ago when we moved house. Kept a few choice components . The initial introductory test will be done on 40 meters . Chanel used for continuous wave cw morse code . My test will be on a legitimate allocated frequency . Later when I have proven principle will test on long wave . Need to build a driver stage , antenna , receiving circuit with motor collection of components photographed : :- - Mike
Mordred Posted July 31, 2015 Posted July 31, 2015 (edited) You know this information is already available. Your HAM radio booklet should have the calcs. [latex]P_d=\frac{P_tG_t}{4\pi R^2}[/latex] [latex]G=\frac{max- radiated -power of -actual -antenna-directional -gain}{radiation -intensity- of omnidirectional -antenna -of -same power}[/latex] P_ t is peak intensity. The recieving antenna only captures a portion of the effective power per square foot. The effective capture area of received power is power density* effective capture area. You can crunch the numbers but you will find you will be dealing with microwatts if not Pico watts at the range your talking from orbit. Not counting stratosphere effects. Then you would also require an immense capture area. Far greater than what is mobile. Edited July 31, 2015 by Mordred
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