WesBrooks Posted April 28, 2020 Share Posted April 28, 2020 8 hours ago, Ed Poore said: Why not get a pot that's double the value but only use half it's travel? That's where I was going with the 'not insurmountable' comment. At the moment I've got a complete system from the Range, aside from this sensor and the bags. I'm thinking the best approach is to get this working, then have a crack at my own controller. The control settings (0-255) from the youtube videos of EASUnlock indicate an 8 bit analogue to digital converter. With a single turn (but no limits) pot attached to the stock controller it would still be getting a 5V signal but the range of valid positions would be halved. The controller (probably bang-bang rather than PID) would probably be only working within a range of 60-80 bits before the swing/radius arms hit their limits. Potentially too small for decent control? Moving it steps towards the full custom controller this is less of an issue. First less stock approach would be to break of the posative supply to the pot and over-volt it so that the range of returned values is in the 0-5V (or smaller to avoid 'fault' readings) range, with care to limit current and clip over voltage from signal to the ground. Having said that I think as microprocessors are so plentiful and cheap now a digital signal back from each corner of the vehicle would be best, there must need to be a fair measure of signal smoothing and transient voltage suppression needed on a 5V signal wire thats 2-3m long which essentially chokes resolution and responce time of the sensors? Quote Link to comment Share on other sites More sharing options...
Snagger Posted April 28, 2020 Share Posted April 28, 2020 The detail going into this is incredible. I thought most making these conversions just strapped a RRC or P38 system on complete and called it done. I don’t understand electronics, so I can’t even follow Gary’s thread about fitting Megasquirt to his 2.5 build, so I admire your ability and bravery in confronting this! Quote Link to comment Share on other sites More sharing options...
Ed Poore Posted April 28, 2020 Share Posted April 28, 2020 4 minutes ago, Snagger said: The detail going into this is incredible. I thought most making these conversions just strapped a RRC or P38 system on complete and called it done. I don’t understand electronics, so I can’t even follow Gary’s thread about fitting Megasquirt to his 2.5 build, so I admire your ability and bravery in confronting this! Electronics ultimately follow some fairly basic rules so conceptually are quite simple to understand. Then this thing called the universe got involved which intertwined all those simple, neat, elegant rules into a massive ball of intertwined bits of string. The Arduino and Raspberry Pi have made things incredibly accessible. Think of them like the Haynes manual for electronics, a really good introduction that will get you started. But once you've played long enough you realise that the workshop manual is much better for getting details from. If you get ambitious like @landroversforever then you throw all the simplified manuals out the window and start designing your own from scratch 3 hours ago, WesBrooks said: Having said that I think as microprocessors are so plentiful and cheap now a digital signal back from each corner of the vehicle would be best, there must need to be a fair measure of signal smoothing and transient voltage suppression needed on a 5V signal wire thats 2-3m long which essentially chokes resolution and responce time of the sensors? I'd be inclined to do this, there's actually a reason why CAN and LIN were developed and even more a reason why they've stuck around. Most microcontrollers can accept a wide voltage ran in now and there are plenty of cheap / small switch mode supplies / LDO that are designed for automotive environments. If they're not stable enough for the analogue conversions then there are plenty of reference chips that will provide the stable voltage reference. For prototyping there's plenty of Arduino form factor chips that are designed to accept a 12V power supply (e.g. the blue pill STM32 ones) 1 Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 28, 2020 Share Posted April 28, 2020 Ed I think you're getting mixed up - the Bluepill boards are 5v powered / 3.3v logic with 5v tolerant IO. Also not aware of many/any micros which accept 12v natively without a power supply, in a nominal 12v car system you need to tolerate ~18v at a minimum with much larger spikes when the starter engages/disengages etc. Also I think adding micros to the pots is way overkill as you then have 4 lots of communications to handle rather than reading 4 analogue voltages which is far simpler - if you run all 3 wires to the pot from the controller you do away with many of the issues with interference / ground float etc. and ultimately I doubt it needs massive precision, the pots are unlikely to be better than 5% tolerance and noise can be filtered by averaging a lot of samples, you don't need to read 1000 samples/second off the ride height sensor and you don't need to make adjustments much faster than every few seconds unless you're trying to implement active cornering Quote Link to comment Share on other sites More sharing options...
Ed Poore Posted April 28, 2020 Share Posted April 28, 2020 Fridge - I think you'll find that the bluepill boards will accept 12V on the VIN pin which is what I was referring to. From memory the LDO used will accept higher voltages - with just enough headroom for automotive use. It's not what I'd personally use in an automotive environment but for prototyping it'll be happy. You've also got to be damn careful which pins you use on the ST devices because not all of them are 5V tolerant and from experience it's also a bit of a sod trawling through datasheets to confirm which ones are. They're also usually only 5V tolerant on input and also only valid on open drain outputs. Quote Link to comment Share on other sites More sharing options...
WesBrooks Posted April 28, 2020 Share Posted April 28, 2020 Interesting to read lots of different takes on the same base topic! I have it in mind that anything thay I build for the truck will be designed to run as normal on upto 24V input, have reverse polarity protection (the MOSFET trick for low power loss), with appropriate noise, and reverse polarity protection. Beyond that I will need to take a closer look at current best practice when the time comes. I think step one will be over-volted pots with a trim pot on the ground side to shift the signal away from 0 if needed. Is anyone familiar enough with the EAS system to know what values are classed as fault readings? Quote Link to comment Share on other sites More sharing options...
Ed Poore Posted April 28, 2020 Share Posted April 28, 2020 2 minutes ago, WesBrooks said: I have it in mind that anything thay I build for the truck will be designed to run as normal on upto 24V input, have reverse polarity protection (the MOSFET trick for low power loss), with appropriate noise, and reverse polarity protection. Beyond that I will need to take a closer look at current best practice when the time comes. There are chips these days that do everything in one, for example take a look through: https://www.analog.com/en/parametricsearch/11394#/. Quote Link to comment Share on other sites More sharing options...
WesBrooks Posted April 28, 2020 Share Posted April 28, 2020 Nice, thanks for the heads up there. There is some good information on the stock height settings on this thread: https://www.aulro.com/afvb/p38a-range-rover/78026-eas-height-settings.html Quote Link to comment Share on other sites More sharing options...
WesBrooks Posted April 28, 2020 Share Posted April 28, 2020 On 4/9/2020 at 11:24 AM, Turbocharger said: The minimum length of the springs is going to be very important - I can see why Robert had those extended bump stops - there's 160mm package volume for the spring at full compression to the bump stop, and I'm keen to design it as if the 50mm bump stop was removed, or at least substantially compressed. Have you got the minimum packing lengths for the classic and P38 bags? Quote Link to comment Share on other sites More sharing options...
mad_pete Posted May 2, 2020 Share Posted May 2, 2020 Found this. I thought it was a useful watch see a system be fitted. System is £3500 apparently. warning - volume on the video is all over the place. Quote Link to comment Share on other sites More sharing options...
Snagger Posted May 2, 2020 Share Posted May 2, 2020 “Handle like a Golf GTI” and feel “like a Range Rover”. I think he’s way, way over optimistic. Really needs to sort his video sound balancing - the music is deafening if you set the volume to hear what he’s saying. Quote Link to comment Share on other sites More sharing options...
mad_pete Posted May 2, 2020 Share Posted May 2, 2020 He has taken those comments onboard it seems. I think he is planing a road review. I think the kit is the 90 version of this http://onairsuspension.uk/full_air_defender_110_130 but my iPhone struggles with that web site. Just emailed them and they will do just the springs apparently just for reference. Quote Link to comment Share on other sites More sharing options...
mad_pete Posted May 6, 2020 Share Posted May 6, 2020 I mailed to see if they do the air bags only and they do for £1750. I found that over budget.... Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted May 7, 2020 Share Posted May 7, 2020 11 hours ago, mad_pete said: I mailed to see if they do the air bags only and they do for £1750. I found that over budget.... Ye Gods ! Quote Link to comment Share on other sites More sharing options...
elbekko Posted May 7, 2020 Share Posted May 7, 2020 11 hours ago, mad_pete said: I mailed to see if they do the air bags only and they do for £1750. I found that over budget.... Bags only or adapters too? A set of Gen3's for a P38 is ~€900, so yeah, still a bit over the top. Quote Link to comment Share on other sites More sharing options...
mad_pete Posted May 7, 2020 Share Posted May 7, 2020 Adapters too, so the bags and adaptors to fit straight in, pipes and fixings. I guess it has some custom billet work to it or something. I’m sure it’s very nice though. 🙂 In theory all this not the turrets. Quote Link to comment Share on other sites More sharing options...
mad_pete Posted May 7, 2020 Share Posted May 7, 2020 I was thinking I could get a couple of bags and take a punt at the rear or something to start or experiment but not for that money. Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted May 17, 2020 Author Share Posted May 17, 2020 Took a couple of weeks away with various lockdown complications... I decided I might do more if it's indoors (and that's half the point of the project anyway). It does *technically* fit indoors on the bump stops, but I snagged a sharp edge on the highest point of the tilt 🙄 Nothing more on the air yet... Quote Link to comment Share on other sites More sharing options...
mad_pete Posted May 17, 2020 Share Posted May 17, 2020 Ouch. Quote Link to comment Share on other sites More sharing options...
PaulMc Posted June 13, 2020 Share Posted June 13, 2020 On 3/30/2020 at 6:16 PM, Turbocharger said: There's several plugs. For each I got the corresponding length off the P38 but that's a limited supply and the wires are old and brittle. Compressorhas a chunky plug with (I presume) power, ground and something from the pressure sensor to trigger it. The solenoid box has two plugs (red & purple) and presumably the slave ECU (yellow) which does the PWM magic. I'll be replacing this with MOSFETs controlled by the Arduino. The purple plug is internal to the box and presumably runs one of the solenoids or a sensor. The red plug would be handy to interface with: Looks like I was smart enough to get the corresponding bits off the P38 too so should be ok with these until I break either. The height sensors each have a short tail of old brittle loom so these will be more of a problem in the longer term. Any ideas for these? The smaller pinned connectors are Econoseal III 070 series - available everywhere. The larger pinned connector is an Econoseal III 250 series connector. Both male and female 250 series 4-way connector kits are available from AutoClick. Male connector kit - https://www.auto-click.co.uk/index.php?route=product/product&product_id=785 Female connector kit - https://www.auto-click.co.uk/index.php?route=product/product&product_id=786 . Quote Link to comment Share on other sites More sharing options...
WesBrooks Posted June 13, 2020 Share Posted June 13, 2020 (edited) Why replace the existing solenoid driver? Edited June 13, 2020 by WesBrooks Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted June 21, 2020 Author Share Posted June 21, 2020 Only a little progress recently, kids + nice weather, and some family things over the last few weeks. Thanks for the plug info, much appreciated 👍 Any idea on these plugs, the electric window switches in a 2002 Defender dash (and a Disco 1 centre console, and late RR Classic - and let's be honest, probably a Metro or Marina too). They look like an elegant way to get inputs that will be glove-appropriate. Today I've managed an hour for some sundry bits, including the bashing and filing to make the Paddock dual spring mounts fit a standard car. Good news: it looks like it'll package nicely. On 6/13/2020 at 9:41 PM, WesBrooks said: Why replace the existing solenoid driver? If anybody knows what inputs and outputs it uses, I'm all ears! No point reinventing the wheel/transistor, though starting from scratch gives me full control of what's going on. Quote Link to comment Share on other sites More sharing options...
WesBrooks Posted June 21, 2020 Share Posted June 21, 2020 Judging by the EAS manual it does the high start and drop for the solenoids from a 12V signal. I'll try to pull together what I saw this week. Quote Link to comment Share on other sites More sharing options...
WesBrooks Posted June 21, 2020 Share Posted June 21, 2020 Is that the P38 front bags fitring with little modification? Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted June 21, 2020 Author Share Posted June 21, 2020 51 minutes ago, WesBrooks said: Judging by the EAS manual it does the high start and drop for the solenoids from a 12V signal. I'll try to pull together what I saw this week. That'd be handy. I've seen the hit&drop graph on the P38 sites but some pinout info would be gold. I'll still use some MOSFETs to drive it but it makes the coding easier. 3 minutes ago, WesBrooks said: Is that the P38 front bags fitring with little modification? Yes, ish. The closed length is still too great but it's got the lower coil seat upside down as a temporary carrier, so there's about 40mm to be had there. I can happily spin off the mounting lug inside the lower seat in a lathe, and/or shape the spring chair on the axle if necessary. I'm aiming for minimum mods though, and not just because I'm lazy... Quote Link to comment Share on other sites More sharing options...
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