Our progress towards a $79 UAV mod kit for toy RC blimps is going well. We've now got a much better, two-sided PCB board that we're having fabbed. It's smaller, has more features and now integrates the IR sensors on the same board (Eagle schematic here; mask files here)
The board is an Arduino (ATMega168 CPU) clone at heart (we call it "Blimpduino"), with:
--Four motor drivers (two 2-motor chips)
--Four IR sensors and associated supporting components
--Ground-based IR beacon
--A choice between rechageable (more expensive) and non-rechargeable (cheaper) Lithium batteries
--Port for Ping))) ultrasonic sensor
--ISCP and FTDI programing ports
Pretty cool--a complete blimp autopilot and sensor package (with one ground beacon) for $79! Don't place your orders yet--we've still got a lot of sourcing and testing still to come--but I'm looking at having it ready for Christmas ;-)
Around $1.50 each at 1k quantities. Looks like the TSOP34856 is $0.70 at the same level, so the benefit isn't economic. However, there might be a weight benefit. The data sheets unfortunately don't show weight.
Ah. Good idea. The original Pololu IR transceivers had that functionality, but we nixed them on cost, weight and size reasons. Maybe the Vishay transceivers would allow us to get the same functionality without those tradeoffs--what do they cost each?
It would be useful if you wanted to use the IR for proximity sensing or if you wanted to do multi-blimp configurations, where the blimps would use the IR to exchange info. However, you could save these features for Version 2.0
Did you look at the Vishay IrDA transceivers when evaluating IR components ? I'm wondering in particular about the Vishay TFBS4710. It's a bit more expensive than purchasing separate emitter and receiver, but there's some convenience in having the components combined into a single package. I'm going to get some samples from Avnet or direct from Vishay, but thought I'd ask first if you had considered this option.
Just to clarify, pins 23-28 are all dedicated analog inputs on the ATMega168 (see datasheet), so they would only be suitable for analog sensors such as touch or light. We only have one free digital I/0 pin, which I will make available for digital sensors or GPS.
If we go to a surface mount board, we can switch to the 32-pin version of the ATMega, which would free up some more I/O pins. That kit would cost a bit more (perhaps $99) since we'd have to ship the board in finished form. We'll see how much demand there is for that...
You read my mind. I've been redesigning the board to add connector blocks for those extra pins so you add additional sensors. Just adds a few pennies to the cost, and won't change the final price..
Comments
The ground beacon is IR transmit-only. The blimp is IR receiver only. We use the Vishay TSOP34156 IR receivers on the blimp board.
I don't really see the advantage of the combined package, because we only need half the components in each case.
Did you look at the Vishay IrDA transceivers when evaluating IR components ? I'm wondering in particular about the Vishay TFBS4710. It's a bit more expensive than purchasing separate emitter and receiver, but there's some convenience in having the components combined into a single package. I'm going to get some samples from Avnet or direct from Vishay, but thought I'd ask first if you had considered this option.
If we go to a surface mount board, we can switch to the 32-pin version of the ATMega, which would free up some more I/O pins. That kit would cost a bit more (perhaps $99) since we'd have to ship the board in finished form. We'll see how much demand there is for that...
You read my mind. I've been redesigning the board to add connector blocks for those extra pins so you add additional sensors. Just adds a few pennies to the cost, and won't change the final price..
-
1
-
2
of 2 Next