Hello all,
I have spec'd out the ideal parts I'd like to use on my (very near) future quad. What do you think? I'd love opinions, suggestions and a good hard critique of my shopping cart and plans.
Like most people I'm looking for the components with the best performance to value ratio, and cost is the major limiting factor in this project.
My goal is to construct an autonomous quadrotor that can navigate both indoors and out with high level of precision in order to complete various objectives.
Ideally this drone will have GPS, a 3-axis magnetometer, barometric pressure sensor and 10 ultrasonic rangefinders for autonomous navigation and to aid in radio controlled flight. I hope to get the quad control board v2 so I can get it flying immediately by RC and my arduino UNO (I will order the APM later).
If all goes as planned, this will lead up to the construction of a second quad with an aluminium frame, massive RC range, an FPV system, larger battery, visual flow sensors and more powerful motors. However, this is way, WAY out of my ballpark for now, both experience and cost wise.
I believe I'll have a short flight time with the battery I am considering (approx 8-9 mins if I'm lucky?), but I am trying to do this as inexpensively as I can. I chose to consider smaller capacity batteries instead of a single larger one due to weight and price, and so that I can always have one charging and in case something happens to the first. If I need a higher capacity and the quad will support it, I can always wire them in parallel before spending more money on another battery.
I may have access to CNC routers and water cutters in a while, so I'll punch out some designs later... but for now I don't have the means, so I think the frame I'm looking at is a pretty good alternative for on-the-cheap flying. I don't expect it to be very strong, but it hopefully won't be subject to much trauma.
My biggest concern at the moment is if the motors I'm looking at will be strong enough to make this fly...
This is my parts list with the cost and approximate weight of the components;
Frame
http://www.hobbyking.com/hobbyking/store/__16583__HobbyKing_Quadcopter_Frame_V1.html
Weight: 195g
Price:$14.99
Motors (x4)
http://www.hobbyking.com/hobbyking/store/__16229__NTM_Prop_Drive_Series_28_30A_750kv_140w.html
Weight: 67.1g
Price: $11.96 (with purchase of quad control board v2)
Motor Accessory Pack (x4)
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=16719
Weight: 13.8g
Price: $1.89
Motor Controllers (x4)
http://www.hobbyking.com/hobbyking/store/__2164__TURNIGY_Plush_30amp_Speed_Controller.html
Weight: 25g
Price: $12.19
Quadcopter Control Board (May not be necessary)
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=19534
Weight: 14.5g
Price: $22.99
Tx/Rx
http://www.hobbyking.com/hobbyking/store/__16238__HobbyKing_HK6DF_2_4Ghz_FHSS_6Ch_Tx_Rx_Mode_1_.html
Receiver Weight: 9.5g
Price: $28.41
Battery
http://www.hobbyking.com/hobbyking/store/__16479__ZIPPY_Flightmax_2200mAh_4S1P_45C.html
Capacity: 2200mAh
Discharge Rate: 45C
Weight: 279g
Price: $22.92
Microcontroller Board (w/GPS, barometric pressure sensor and 3-axis magnetometer)
https://store.diydrones.com/APM_2_0_Kit_p/br-ardupilotmega-03.htm
Weight: =< 50g ???
Price: $199.99
Ultrasonic Distance Sensors (HC-SR04) x 10
http://letsmakerobots.com/node/30209
Range: approx 2-500cm
Weight: 9g
Price (on ebay): $4.00
Propellers
Price: $3.48
Approximate weight of quad without wiring, props or epoxy: 1061.6g
Approximate cost for the above items not including tax: $433.46
Thanks everyone!
- Calvin
Replies
Wow I was to respond but Jani beat me to it... :)
As Jani said, your list seems ok, Frame is really cheap...
HK have great prices, shipping is hight and takes time so overall do the math and see if buying local "DIY DRONES prooven" parts would be better....
We have put a lot of work on these kits and parts... sometimes it's easier to start with our experience instead of from scratch. But what ever you do, keep up posted! This is how products evolves around here!
Best of luck!
Dany
www.CanadaDrones.com
Few quick hints....
Forget that HK frame, we have two of those in here and well it costs 15 USD and that's what you get.. 15 USD worth of badly pained and fragile plywood. That frame will break almost immediately on crashes. And you are planning to make your own system, prepare for a lot of crashes.
During our ArduCopter project, we have been destroyed totally maybe 10-20 full quad kits and crashed several hundreds of times so I could say, We know... :)
Motors looks rather ok thou we never tested them but in generally you should be able to lift about 1 kg of total weight with those with decent power levels. You might check other propellers as HK 10x6 are not the best ones.
Change your radio. If you put a bit more money on it you can get already rather nice Turnigy 9X radio and 8 fully working channels.
Dump that Quadcopter control board as you cannot do with that anything else except free flight, it does not have "any intelligence" inside. Merely gyros and their control electronics/program.
Either take APM1.0 now with all parts on it or wait 2-3 months while APM2.0 is on market. APM1.0 is really good if you want to start now.
10 sonars... Umm houston we might have a problem. You need to be careful when playing with those as you cannot run them all at same time. You need to let area to be "silent" again before sending another sonar pulse. So you need to have custom electronics to fire them in sequences and then read values one by one. You either need huge amount of analog/digital ports to do that which none of the current flight controller electronics have or you need to have multiplexer electronics and just spend one analog/2-5 digital to control them.
In anycase I would say, forget 10 sonars. You just cannot have them as there are a lot of interference coming out from quads that messes up sonar readings. Horizontal measurement is almost impossible due all the noise that motors, regulators, airflows etc are creating.
Why don't you look one of those ready made kits that are already on market. Like what we have at jDrones, DIYDrones etc.
They have been made in way that you don't guess if it's going to work or not. And still you can easily modify them for your bigger needs. Whole ArduCopter project was created by us to help beginners to enter this world easier as we knew and saw how many people there are struggling with all those million different possibilities.