Tesla made their July 2012 delivery date in grand style on June 22. Video of the event HERE.
This week, I could not help but comment on both the paramilitary precision with which they are executing this very heartfelt dream, but also the audacity of what they propose.
By way of comparison, the Audi A8 ($78,000) and BMW 750i ($84,000) are really very similar cars in all respects. Their appearance is very close to the Tesla, in weight they are similar, and most of all in price they are similar.
BUt the Audi sold 5700 cars in the U.S. last year and the BMW750i only sold 11,299. That Tesla would introduce a new sedan, otherwise similar but with range - limited electric drive and expect 20,000 sales the first year borders on the preposterous.
I think if they fall short, it will be by inches.
Beyond that, it's all good news. Already this weekend since we shot the video they did release some weights and the Model S is somewhat more porcine than I discussed at over 4600 lbs. That makes their 375 Wh/mile look considerably better.
As for us, we suffered the thrills of victory and the agony of the feet all in one week with the Elescalade.
Jeff Jenkins of EVnetics kindly provided two circuit designs to spoof our MAF and MAP signals. I had pretty much came to the same chip with the Manifold Pressure Signal and in fact had one built. But we needed a voltage controlled oscillator design for the Mass Air Flow signal badly and he came up with a good one.
In any event we obtained the parts and I clumsily soldered the little circuits together onto some bread board and wired them into the vehicle.
Along the way testing them, we just went to hell on tachometer signals. First, we lost our THIRD Westach 702-12R we've had on this project. Maybe our voltage is a little high at about 14.5v, or maybe our magnets are two strong, or I don't know what. But we blew up two pronto and the third lasted about two weeks during very light testing.
This is the hall effect magnetic pickup we use to send an RPM signal to the Soliton 1's. So we bit the bullet and went with EVnetics recommendation for an Automation Direct AM1-AP-3A inductive proximity sensor. Turns out to be a pretty good recommendation. This sensor will pick up bolt heads or gear teeth or anything ferrous. We tried it on our magnets and it worked great. Plus it has a little LED that flashes each time it pulses so you can visually see it working. We loved it. We've added it to the online store HERE. It's certainly the one to use with the Solitons.
Once we had that on, we could START and idle again. But our sensor for the Escalade reluctor ring was acting up and it needed to be impossibly close to the teeth to do anything. We actually obtained a replacement on the chance that the one we had was faulty. No luck. We finally got it aligned, but it would drop out as we increased rpm. The mounting plate was apparently vibrating. So we remounted that with a piece of rubber ROOFING TAPE.
It improved dramatically.
And so. With both sensor spoof circuits, and both tachometer sensors working, we were FINALLY able to start the vehicle simply by setting the key to IGNITIION, and then START. The Solitons fired up the motors and quickly reached an idle of 600 rpms.
Without the MAP and MAF sensors, when we would accelerate, the ECU would quickly throw a diagnostic trouble code and slam the throttle plate to idle. It then sent an advisory to the screen in the dash - REDUCED ENGINE POWER. Well hell yes its reduced, you've reduced it to idle.
But with the MAF and MAP sensors deployed, it seems satisfied for the moment to allow us to accelerate using the throttle.
Let's talk about the circuitous route all that takes. The accelerator sends an accelerator position signal to the ECU. The ECU sends a throttle drive signal to the throttle, and receives a throttle position signal back to the ECU. We use the TPS as a throttle INPUT to our two Solitons through an opamp buffer. The Solitons then actually drive the motor of course.
By the time we get out of the opamp, our whole range of throttle signal is 1.9 to 4.3v. So the throttle feels a little "touchy".
Fortunately, the Solitons have another adjustment where you can set the amount of power provided at half throttle. We reduced this from the traditional 50% of power at 50% throttle to 35% power at 50% throttle.
This gave us much finer control at low rpms. Of course, having 35% range on the lower half of the pedal position leaves 65% remaining power for the LATTER half of the pedal throw. But you should expect this sort of tuning "for feel" on any EV project.
This also interplays with the amps/sec ramp rate on the Soliton. You can set this from a couple of hundred amps per second up to say 5000 amps per second. This is the rate at which the SOliton will ramp up power to the motors. Too fast a rate and you snap axles. Too slow a rate and your pedal feels sluggish and delayed.
In any event we FINALLY got it all cobbled together to the point where we could get in, turn the key to IGNITION, and here we have to pause for just a second or so delay for the contractors to close and the SOlitons to come up. We're going to add an LED to the dash using the Soliton RUNNING output to signal this "ready" situation but you can hear the contractors. Then to START. We had of course located the signal the ECU sends to the starter on the gasoline engine, and wired that into the Solitons AS a START signal.
The Solitons run up the motors and quickly find the 600 rpm idle speed. Note that we have all of this going to TWO Solitons and two motors. I cannot detect any unusual hunting for rpm or "fighting" between the two systems to bring it to idle. They appear to work very well in tandem this way. Of course we have all the other settings setup identically as well with the exception of the optional OUTPUT gage drivers. But given the PID circuits in the Solitons really act independently, we did not know whether they would "play nice" with each other or not. But it appears they work VERY WELL together. While we have two motors, they are on the same shaft and we have ONE tachometer signal, whenever we can keep one running.
With the MAP and MAF sensors in place, and the crankshaft position sensor, the ECU seems reasonably happy. We can very smoothly accelerate up to about 3500 rpm which is as high as I can bear with it loaded only by the torque converter. It is quite smooth, both in acceleration, as well as vibration and noise. The blowers on the motors make more noise than the motors of course but the entire installation is very nearly vibration free.
At idle, the system draws between 11 and 14 amperes at 188 volts. That's a 2kW idle which means without air conditioning, just turning the motors and the power steering/brake pump, we use 2 kWh per hour sitting there. Not a great feat of efficiency in an electric car. As this car will probably average 750 Wh per mile, idling for an hour would be the equivalent of about 3 miles range. Viewed in that way, it's not too bad.
And so early Friday afternoon, we went to shoot some video of all this and explain our sensor spoofing. Just as we turned it up, we heard a loud pop and everything went dead. We never did find the pop. But it took three hours to figure out what happened. We had NO 12 volt power. Our rear DC-DC converter read about 2.5volts. If we disconnected the load from it, it was happily 14.5volts. But when we hooked the load back up, 2.5volts.
We entered three of the most frustrating hours of troubleshooting I've encountered in some time. If we pulled the fuse block, we were at no load of course and had our 14 volts. So we assumed something was loading the circuit heroically. We put the fuse block back on and pulled EVERY SINGLE FUSE one by one and every relay on the fuse block. To no avail.
After three hours, we discovered that our battery box, which we had used as a ground for the rear DC-DC converter, and which had always worked fine, really didn't have a ground to the frame of the truck. We could READ the DC=DC voltage as long as no load was applied, but it couldn't supply any significant current at all as it had lost a good ground connection. This is about the fifth time I've cured something that was driving us crazy on this truck with a GROUND solution. ALL the grounds in the wiring harness are there for a purpose and needed. They do not tie together at some central point. If you miss one, you have a problem. In this case it was OUR added equipment, but it didn't matter. A ground was the solution and it fixed it completely.
Of course, that meant we got to shoot the segments of the video looking into the Elescalade at about eight o'clock at night and THEN do the broader segments on Tesla et al.
Do I sound like I'm complaining? Fear not. I'm in my salad days here. In the first place, I LOVE it when something is screwed up and I can't figure out what it is. The day everything just works and there is nothing to troubleshoot is the day I walk out of the garage and the end of your weekly fix of EVTV. I only play on the frontier of things. I don't do well with "townies."
But this was a very good day of winning milestones along the way. I am totally devoted to the concept that everyone should drive magnetically driven personal transportation - electric cars. I don't actually think we need to give UP anything. We can play with ICE vehicles as antiques for the next 200 years. If we got half the people to do HALF their miles electrically, the world is just entirely different in so many simultaneous good ways that it will be incredible to watch this all unfold.
But I almost singularly REALLY DO understand how technological change happens in our population. And this change falls almost entirely on two factors. The first is, you have to have DESIREABLE cars that are lusted after by early adopters. And second, you have to have information sources to disperse that info to the population - better trusted sources. TV advertisements and press releases don't cut the mustard in this case.
If anyone is to adopt an electric car, his first official act will be to talk to someone he trusts who actually lives with one. Let me reiterate, the check ain't a happening thing until I talk to probably SEVERAL people who live with the new technology and clearly gain advantage by it. That's manno a manno kemosabe. A super bowl ad won't do it. No first person recommendations, no check. And I have to be persuaded the first person is not a copper foil helmet kook who is also trying to keep his dog from reading his mind.
Tesla has built a plant in Freemont California to mass produce an all electric all aluminum sleek looking European sedan with enough computer power in it to edit my videos on. Lust.
We build Speedsters which are automatic head turners. I can't go to the grocery store without hearing about it. The Elescalade is a POWER demonstration of the same thing. It imprints the concept of ANY car. It's not a very practical example for most. But it will be impressive.
And the cars you build, from a Porsche 914 to a VW THing, to a GT-40 right down to a 1939 Dodge Brothers half ton pickup truck and yes, including a Glastron power boat, where done well, are a demonstration of the same thing. And YOU are a first person trusted source to dozens and potentially hundreds of people around you.
I cannot adequately express, or persuade or put into words how very powerful this is. It is NOT the usual gratuitous "if we all join forces together" power to the people bunch of horse shit that many of you would be perfectly willing to accept. EACH one of you has ENORMOUS power to influence others by the dedication of your ducats and handwork to this cause. It actually causes CONSTERNATION in the populace. Gas prices are this. Cars are that. We are told this. We know that. But then how come this old man in Lexington Kentucky can make a 1939 pickup truck run on no gas? And he seems HAPPY with it. What if it doesn't go as far as he wants to? Ah, but what if it does?
Pebbles in a pool? How about a small block V-8 dumped into a bathtub. The effect you guys have on the world INDIVIDUALLY is so far beyond what you are aware of it is nearly comical. CUMMULATIVELY I don't even know what it means. You are unaware giants walking among aboriginal pygmy dwarves. While they watch TV, you build your electric car. While they whine over every ducat, confident in their knowledge of the cost of everything and the value of nothing, you spend on parts they can't comprehend after you've explained it. If you don't know what it DOES what difference does it make what it COSTS?
The mission is not to put every one into a 1939 electric truck. It is not that everyone can afford a Tesla and should have one. It is to make them WANT one. It is to build desire, awareness, and demand. The design. The manufacture. The costs and the pricing. All follow from demand. It is not the other way around. Demand doesn't build as the costs fall. The costs fall BECAUSE of the demand.
You guys are the flag wavers. We've had flag wavers in the past. They mostly waved the flag. They didn't actually buy or build electric cars. They were "activists" and "environmentally aware" and they even "demonstrated". Largely in futility and yes, I dismiss their efforts as almost entirely salutary and trivial. The sum total of them all wouldn't warrant 12 minutes out of one of my days. Lots of people have truly profound opinions on what others should do with their money to make the world better for us all. Noise. And not very useful noise frankly.
But when you commit to a project to convert an existing car to electric drive, pursue it to completion, and then demonstrate it to all who have an ear to hear and an eye to see, the effect is sufficient to change the world on its path. And I am pretty much personally committed, 24x7 and with every breath drawn, to aid and abet you on this mission where and how able.
Whether you do or not, I know who and what you are. And there are not yet enough of you. There will be more...
Meanwhile we struggle with the twelve blind men around the elephant effect, each struggling to describe in words what an elephant looks like. Brandon Hollinger believed he liked electric cars. This week, he upgrades his Saab96 from lead to LiFePo4 and now has lithium underfoot on the road. The difference is the difference between a science project and a car. And now he knows ALMOST as much as his mother does about electric cars. (She drives a lithium Miata). The Saab went 119 miles and had 30% SOC left and it gets scratch on takeoff now. As he drives this daily, the marvel will grow - not subside. And if he thought he had drank the kool-aid before.....
The heart of this is the marvel that becomes a mantra "If people just KNEW about this, they would...." That's the feeling I get every single day.
Spread the word...
Jack
Editor Rotundus
Sunday, June 24, 2012
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Top marks for this epic video and all who contributed.
ReplyDeleteInterestingly I've been rummaging the 'net for good idea's on the circuitry front and this supplemented it all quite nicely. The circuitry offered was far better than what I could achieve with a pair of pliers.
I'm including an NTC resistor or SCR with a slow feedback with the safety diode for low load soft starting capacitive (or any) loads like DC-DC converters, air conditioning electronics, controllers, what-have-you.
http://en.wikibooks.org/wiki/Power_Electronics
So much more to add but not yet. ;)
I am glad you got your signal spoofing mostly sorted out. With a little twinkling of the resistors and caps you can probably dial in the Manifold pressure a bit tighter. Analog circuits have always driven me crazy and are not my specialty.... I can do them, but they wind up being a lesson in learning how to cuss...
ReplyDeletework is progressing on the EVThing. Engine is out, trans is out. Sand blasted and painted the engine compartment. If my back holds out I should have it running by EVCCON...
Just bought our conversion vehicle: a European shaped 2007 Civic. Looks like a flying doorstop but my son thinks it is seriously cool.
ReplyDeleteOne of the things that I've been doing since EVCCON is to allow anyone I know, who has expressed an interest in my EV, to drive it. Truthfully, I've been the one to bring it up on many occasions. I announced to all my co-workers, that anyone who wanted to drive it could. They lined up, and they loved it.
ReplyDeleteIt's like Jack had said sometime ago, "You can't appreciate the difference until you experience it for yourself." At EVCCON Jack encouraged everyone who had brought their EV to find someone that had never driven an EV and allow them to experience that difference. I carried that request away from the convention and have worked to get as many people's butts in that driver's seat as I can.
They know I built it. They know I drive it every day. They know it goes as far as I need it to go and they know that it costs almost nothing to drive it. And after they jump out, they know what it's like to drive an EV. That experience carries weight; they remember it. When it comes time for them to get a new car, it might just carry weight in that decision as well.
That may be the single biggest thing I can contribute to the cause.
The first single biggest thing, is to build a car. The second is to share it. It is just ENORMOUSLY powerful. The shockwaves sent out from that central act are so widespread that unfortunately you don't get to observe them or their impact. Just the EV grin at the beginning where it lands in the pond.
DeleteAbsolutely true.
Tim, your blog about your conversion was a big inspiration for me getting started on my Porsche 911 conversion and blogging about it.
Deletehello Jack, again very nice show .
ReplyDeleteI´m converting a Smart fortwo car and I found that signals from the Curtis 1238 are reference to battery pack negative and the ECU to 12V negative, so I had to isolate signals going from the ECU to the Curtis 1238 , and from the Curtis 1238 to ECU , so I dont have a frame leak from the battery pack.
So the question is : are the signals from the Soliton isolated from battery pack negative ?
best regards
That is an EXCELLENT question Celso. I have to believe they are as the outputs are meant for gages and so forth. But I will check this TODAY.
DeleteJack Rickard
They are. The Soliton and the Zilla run from the vehicle 12 volt power source. You can not do this if you're tied to the traction pack in any way.
DeleteThe Curtis controllers (1238,1231,1221, 1253 etc.) on the other hand are entirely powered by the traction battery. All signals are referenced to the traction pack negative.
Hello Jack, very nice show, like the way you can spoof the sensor inputs. For me I don't have enough elctronics knowledge to do what you do.
ReplyDeleteI would like to explain what I found about 30 years ago when me and a mate put a turbo on a 2000cc triumph 6 cylinder car we actually set it up with the 2500 mechanical timed fuel injection modified to do fuel enrichment on and off boost and low and hi vacuum mechanically.
What we found was the vacuum for this motor was about 10 to 12 in mercury at idle and about 3/4 inch at full load now this was not dependant on revs so much but on throttle position. I will try to explain it as best as I can. At idle fuel was about 1/4 of what it was at full load at same revs. ie if we use on time for electronic injector say 2ms at idle and about 8ms at full load at the same revs. This relationship will have to be worked out for the escalade vacuum to injector on time.
In the earlier days the automatic transmissions had a modulator diaphram connected to the manifold so the auto could work out the engine load dpendent on the vaccum of the engine. Cruise hi vacuum, floor accelerator low vacuum and auto trans would select right gear for the situation.
This is all done by the magic of electronics now. What will probably happen when you drive the escalade on the road the transmission might not select the right gear. If you could link the MAP sensor out put to be driven by the amps the motors use ie High amps equals low vacuum (flooring accelerator)and low amps equals cruising (light throttle hi vacuum). As I understand it the MAF sensor just measures the amount of air flowing into the motor and The MAP sensor measures the manifold pressure (ie the load on motor) and these are referenced to engine revs in some non linear relationship dependent on the particular engine.
Hope this explanation makes sense and helps
Best regards
Haven't watched the show yet, but your blog reads as though you are channeling Ralph Waldo Emerson. As my profile suggests, this is a compliment. I know you said you don't travel well these days, but you and Brian on the road with the Speedsters and Elescalade in tow would be great hands-on PR and get us to the tipping point all the sooner.
ReplyDeleteJack,
ReplyDeleteA few things did get me thinking however as it relates to your signal spoofing.
Most PCMs over the years have done a number of checks and balances in regards to signal integrity. Unfortunately those decisions were based on the dead band area of the signal.
OBDII added rationality checks to fray. This allows the system to know whether the signal is valid for all conditions.
The MAP performs a “load” and BARO function at KOEO and with WOT at low to mid RPM.
Factory fuel and timing mapping records MAP, RPM, TPS, IAT & ECT for numerous engine-operating conditions. Airflow is measured by industry standard. Dyno data is arranged on 3-dimensional graphs and algorithms formed that allows the PCM to know precisely what load (torque & HP) the engine is developing.
The PCM is constantly running a rationality checks. You have already confronted this rationality stuff in the Drive-by-Wire TPS. The signals from the TPS must coordinate within a given window or the PCM throws a fit.
The MAP signal is a crosscheck for the MAF signal. With given MAP, RPM, TPS, and IAT data the PCM knows the “X” amount of air mass entering the engine. If the rationality check is not within tolerance a code is recorded and the PCM defaults. Many owners will never know that something is amiss except that the CEL is on.
As it relates to transmission operation, TPS, RPM, VSS and MAF, for the most part, control the part throttle and comfort zone shifting of the transmission. MAP adds the most important information in regards to load or power that is coming from engine. The MAP and TPS sensors perform the TV or kick down and vacuum modulator functions that we had on the old mechanically controlled automatics. MAP, MAF and TPS are the biggest control inputs for controlling line pressure. They affect the TCC function and with the other inputs fine tune the shift points and comfort. I am not completely familiar with the trans operation in your vehicle, but from past experience MAP may have some effect on skip shifting function as well. If there is a conflict of rationality between the MAP, MAF, VSS, RPM, TPS relationship the PCM may go to or remain in default mode. If things go far enough out of whack it could make sorting out tranny function a real headache.
It has been a while but I believe the system will default to MAP based control as its basic function as MAF sensors can become skewed to the dirt and other environmental issues.
In the case of your MAP spoofing I believe it has a few glitches. First off it is not a real indication of what engine load is.
One thing electric motors and ICE have in common is they both have a direct relationship to load. ICE vacuum drops and electrical, amperage goes up.
In order to make things a little more accurate might I suggest that you use the signal from the amp shunt to give a more accurate indication of motor load. A circuit could be made up that could convert that quite easily I would think. In this way the PCM would see values that better match the lookup tables.
Another tidbit is the ECT sensor. It is a small player in when certain functions happen as well. In the original form it is used to inform the PCM when the system can go to full closed loop control. It can also be used as a cross check to the temp sensor in the transmission. If the ECT is not showing a “normal” operation temperature the PCM could change transmission operation because it is thinking something is amiss. As an example it may prevent TCC if it sees the engine in not up to operating temperature. This would probably be overridden by the PCM time based rationality check and default to trans temp input. Because the PCM still thinks there is an ICE installed it is looking for real world operating temperatures of between -40 and 250 degrees. It also expaecting to see engine operating temperatures in the 170 to 230 range after the timers have turned off. If it is on the high end it throws things into protect mode so to speak. If too cold things just won’t happen for a while.
Just my $0.02 worth.