Thursday, 29 April 2010

VIC-E Back up and running

Replaced the chips in VIC-E and have spent the day testing the new control electronics. Have had a few teething issues, most of which could be fixed with suppression diodes!
 One problem I have been experiencing is sticky relays, something I have not had an issue with before, but have read an article that defines the problem being partially caused by back EMF protection diodes. I have ordered up some zener diodes to place in series with the protection diodes which should help. However, I'm slightly concerned that the relays are arcing together, they are 6A relays, and the valves are 2.5A max, I'm sure there is a larger start-up current, but the relay should handle 15A no problem.

Tuesday, 27 April 2010

More delays!

Found out today that the waterjet cutting has been delayed, due to a machine malfunction, great! Also just noticed I have fitted the wrong RS485 driver chips in VIC-E, so out comes the hot air solder gun :)

FACU renamed: VIC-E

VIC-E (Valve Interface and Control Enclosure), pronounced Vicky. Assembly is nearly finished on this unit, I have checked most of the functionality, such as the DAC and power relays. The 5V power draw is quite high, which causes the voltage regulator to get pretty hot! I have reduced the current draw from 187ma to 155ma by switching off unused peripherals on the dsPIC and reducing the drive to some of the LED's. It is running ok, but I may still glue a heat-sink to the VREG, or replace the LED's with low current versions. Irritatingly I missed a bunch of pull-up resistors on the main board, so had to bodge some on!

Monday, 26 April 2010

SID box complete

SID (Signal Distribution) box has been completed and has come together very well. Needs to be fully tested on the leg.

Tuesday, 20 April 2010

Pilot/Operator Chair

Just received our operator chair! First impression are good, the chair has a good range of adjustments, its comfortable, has good adjustable arm rests and of course weight compensated suspension :) We will fit the controls directly to the arm rests, to minimise fatigue and maximise precise control.

Friday, 16 April 2010

FACU V2 build

The remaining components arrived for the V2 FACU controller, so I have nearly completed the assembly. I have yet to machine the box to take the board, so I will work on it on the bench for the time being, just to get the firmware up and running.

Wednesday, 7 April 2010

Operator Interface software

I have started to look at what development environment to use for the operator interface GUI. As this needs to be a fast boot lean system, I think it will run on Linux, and so far I have come up with Qt. I have installed QtCreator on both my Xp and Ubuntu machines, so far so good. I am developing a simple app within Ubuntu first, just to get all of the OI comms working between the GUI and the HexEngine, then I will start to get something a little more sophisticated together, and ultimately ported to the target system, which is yet to be defined!

Monday, 5 April 2010

Larger sized foot

We have changed to foot for a slightly larger 300mm diameter tyre. It looks more like it should be the correct size, although the tyre does seem slightly softer, so we will need to check it doesn't get crushed too easily.