Hi,
Vital Byte's skipper screws it up!
Vital Byte's latest voyage was down at Dover at the weekend (not in the Channel but at Kearsney Abbey!). The Model Boat Association Dover had its annual open day on Sunday and the oportunity was taken to do some test runs and play around with the control settings.
Questions were naturally asked about boiler certificates etc., but it was soon understood that none were required for a flash boiler.
The first run was going fine for the first 15 minutes, until Richard from the Maidstone Cygnets MBC made the remark that the response was very impressive - that was the death knell! Vital Byte was going at Warp Speed 9, when it became apparent that steering was not what it had once been - "She's not answering the helm Cap'n" cried out an imaginary Scotty from the engine room!
As we were literally heading to the rocks something had to be done fast - luckily the engine went into reverse, VB slowed down and Alan Poole, of the Dover MBA, quickly organised a rescue mission. With the use of other members boats, VB was nudged to the shore. Thanks all round.
A quick examination revealed that the servo to rudder adaptor had become loose ( all that showing off of the response!); with a quick application of the screw driver, VB was soon back out on the pond, but without the skipper throwing the rudder all over the place.
VB did two long runs - one of 31 another of 44 minutes, the timing being done by VB itself. The new software features worked (except for total revs for some reason) and maximum and minimun parameters were logged. Gas consumption was 4.0g/min for the first run and 4.5 for the second run.
I did alter the feed water controller for the second run a bit too much and VB stalled out in the middle of the pond and became stationary - another rescue mission was offered by club members, but this became a test of its automatic recovery mode of operation (the Mars Rovers have nothing on this babe!). After a few minutes a wisp of steam was seen to rise and slowly VB came back to life.
I managed to capture some valuble data and will also now incorporate an average RPM reading. The maximum RPM achieved was 570 although I'm aiming for 800 which is what I obtained from Malcolm Beak's equations.
At the moment I'm trying to understand where the limitations are - gas nozzle size? gas consumption? heating area? etc.
Thanks once more to Dover MBA for their help and interest.
Ian.
p.s. One secret development I've not mentioned is the Carbon Capture environmental feature of the boiler. This was secretly photographed by Alan Poole of Dover MBA and I have obtained an exclusive copy for Mayhemers! The green carbon capture spheres (CCSs) are collected from the pond after the experimental runs! (see attached photograph).
Hi Mayhemers,
Warning: this post contains computer speak!
Whilst waiting for some fine weather to test Vital Byte, I've started on the new control computer (designated the AE35 unit) which, hopefully, will be about a third of the size of the original and will fit into a smaller range of boats.
I'm also taking the oportunity to strip out a lot of redundant code and give the data displays a better layout. The AE35 will be using serial communication between the chips in place of parallel comms and the dedicated analogue and digital signals.
The test board for learning how to use serial comms is working and I'm now migrating the RPM software into the PIC chips for testing.
Previously I was using 40-pin PICs for measuring the pumps and engine RPM and have now replaced them with 18-pin PICs, thus saving a lot of room. Also, one of the original 40-pin PICs was totally redundant.
When using parallel comms, the Veroboard had 15 tracks dedicated for communication - using serial has reduced this to just four, thus another space saving measure.
Hopefull, Vital Byte will be testing its new "brain" (the AE35) before Christmas.
Meanwhile, back in the machine shop (shed!), the feed pump for the steam jet engine is nearly complete and the boiler casing will be started on soon.
I'm up at the Warwick International Model Boat show on Sunday, flitting between the Maidstone Cygnets stand ( with the 13ft HMS Kent) and Blackheath's stand chatting with Phil Abbott about --- flash steam - what else!
I hope to see some Mayhemers there.
All the best
Ian G.