Recent content by Gepard

Hi, I'm trying to draw a Cardinal Spline and understand them - however I can't get my head around the formula. Now, after lots of research I keep coming back to this formula: Ti = a * (Pi+1 - Pi-1 ) taken from this page(there's a similar one on Wikipedia)...

Hi, I'm currently designing a model torpedo and plan to use compressed air for it's propulsion and am working out if it's feasible. At the moment I'm trying to calculate how long it takes for X volume of compressed air at Y pressure to leave (IE return to atmospheric pressure) through a...

Thanks Cristo, that makes a lot of sense. Cheers, Michael

Hi, Apologies if this is in the wrong place but I've no idea what *it* does... I should just mention that I'm currently doing my A-levels (16) and so my maths skills aren't that advanced... The problem: I've found a paper on the Kalman Filter on the internet (source...

Wow thanks Tom, I'll look over what you gave me and contact you if I have any problems if that's alright? Michael

Already considered it, average radio control submarines can go 10m max in fresh water, in salt water, barely past the surface. I'm looking for 15m+ Still waiting on the speaker to arrive... Michael

Wow, I'm impressed by the RX. Here's the result: http://www.mhims.co.uk/Sub/acoustic%20recording.wav (Sorry about the end :D ) I tried to use a loudspeaker in a water box to produce some sounds and see if they could be picked up at the other end however they were just getting stopped by the...

Right, about to go to bed (late here in the UK) the tubes are lined up, horizontal (about 5 degrees out which I'll change tomorrow, capped both ends, and filled with water. As my garden is on a slope I had to use wooden blocks to raise one end. I've also cut a hole in the top at both ends using...

Well been and picked up the tubes, going out later to get some piezo transducers.. At the moment I'm just going to try submerging a piezo siren that's designed for air, no plans to go ultrasonic just yet, want to build the RX and see how well that performs. In terms of money I'd say $200...

Thanks for the link, I'll have a look, I'm going to setup a tank in the back garden tomorrow. 10m long made up of drainage tubes and probably some sort of lining to adsorb some waves. I've got a piezo siren which I'll take apart and build an preamp to add to the rx piezo disc and see what...

Oh, one point I ought to make is that the AUV will be run in a fresh water environment (local pond) and so traffic in the area will be minimal. Michael

Thanks for the link Michael

Only book I've looked at Physical Computing, a run though of circuit basics. And everything I've learned for this topic has been in the last 24hours staying up well into the early hours reading all sorts of PDFs and reading through old forum posts etc. It was this thread...

I start electronics classes in September, everything I know at the moment is self-taught. Although I'm very keen to see this project through as lot (both time and money) has been invested in it. Not looking for a detailed what-to-do, just areas I should look into/ investigate etc. Other...

I'd say <50bps, I just want to be able to get something working that I can improve upon as time progresses. Not looking for the ideal solution first time round. Michael