Tesla Cybertruck Steer-by-Wire System
Sandy and Armin demonstrate how steer-by-wire works and examine the components that make it possible in the Cybertruck.
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#tesla #cybertruck #elonmusk
For a second I thought Armin was a Jordan but super sized 😂Both are buff looking dudes
i did the same thing. then he started talking lol
yeah lol
They could joke around and call each other “ twins”
my first thought was, is that his bigger brother?
@@ralanham76 [twin spider-man meme]
Glad to see other Munro team members showing their expertise in these tear downs.
They are experts in “reverse engineering” LMFAO!!
@@Gr0gansm1th You're underestimating reverse engineering?
I can honestly say I didn't think this was going to happen but I'm taking delivery of my cyber truck before Sandy finishes the teardown.
And it’ll be rusty before he finishes it 😂
@@kentonian wow you are really out of touching that one
@@kentonian Cybertrucks don't rust. Try to keep up.
@@kentonianand youll still be a tard
me, too, I hope.
Jordan had a growth spurt! Haha. Great video guys!
Thanks for watching!
Roids.
At least a foot taller
@@richardkule9384no. KISS boots. 😅
lock-to-lock is closer to 340 degrees. From centered to max turn is about 160-170 degrees.
You REALLY need to get your eyes checked. LOOK AT the video again. IT IS NOT 340 degrees. It is more like under 300 degrees, maybe 280 degrees is more like it. 360 is the full circle.
@1flash3571 he is correct 170 degrees.
@@1flash3571 he is correct - there are pictures of the CT screen showing +/-160-170deg steering wheel angle for lock 32deg at the front wheels. So 320-340deg lock to lock depending on the ratio provided (by nature of the system it can be changed to even less SWA required)
@@felixweinreich3999 Soooo, when SM did the ACTUAL TURN, that is FAKED???????? WTH you talking about????? I saw what I saw, and he turned it from left to right to the MAX and it wasn't 320 degrees.
@@1flash3571 SbW is variable gear ratio! You could also do plus minus 10deg lock to lock if you want to... but actually cybertruck on the road has standstill lock to lock around 320-340deg!!! Will be different when you change the vehicle speed (even more indirect ratio) Cybertruck shows the data on the screen with steering gear rack travel, steering wheel angle and road wheel angles...
As much as I like Tesla and the Cybertruck- I have to point out that the 2 ribbon cables which provide steering input commands to the rack and pinion motors does not qualify as redundant, much less "double redundant" Both ribbon cables share a single connector which means the connector becomes a single point of failure that impacts both systems. This concerns me as it would not qualify in an industrial application as "redundant" much less when applied to a "people mover" application.
Thought the exact same thing. There also seemed to be an implication the steering motors were powered by that ribbon cable, which is clearly not the case. Also, no doubt the front module just communicates with the steering motors/sensors using can bus. Also find it intriguing that a massive connector almost the size of a human hand is apparently a marvel compared to a simple, compact and cheap 4 pin connector which would otherwise be used (12v, gnd, can high, can low).
Agreed, redundant would be two separate cables taking separate paths to separate ports.
Sandi pretends to be all knowing, expert on all subjects, that's the worst kind, pretend to know, blow smoke, hope the check clears. Another fake, phony fraud...And he doesn't understand what vertically integrated means either. He claims Tesla is, tesla is far from it. What a tool.
3 cheers to Sandy and his crew for yet another so nice explanation.
really ??? :-)
Wait, so the redundancy on the cabling is done with cables that are TOUCHING each other? So if some physical damage occurred to one wire will very likely affect the other wire set that is TOUCHING it? Crazy.
Truck is Stainless Steel , NOTHING can penetrate.
@@markplott4820Penetrate? Wires don't need to be penetrated with external stuff to get cut... Besides, most of Cybetruck is built from anything but stainless steel.
@@markplott4820 only the outside...far away from these wires that can easily wear on other things...ive seen wires that are rubber coated in rubber clamps still wear through fully and short
whoa keyboard engineer! don't jump to conclusions..
@@stunnerdoc true
One of my favorite things to do in my Cybertruck is u-turns. Especially when I have someone with me who drives trucks.
A regular Toyota Hilux has a shorter turning radius though, so I doubt they'd be impressed.
@@logitech4873 A Hilux is a much smaller truck. Like, MUCH.
Until your accelerator pedal sticks and ur doing doughnuts at 120 mph. Good luck champ
@@FrickYourHandle hater gonna hate
@@logitech4873turning radius? Wheelbase of Hilux?
Thank you for bringing that to us. Surrealism defined.
Great video, very educational. It's all about the tech! Thanks guys.
Thanks for watching!
@@MunroLive this isnt a true 48 volt architecture another tear down company on autoline daily proved it. plus the honda prelude back in the 80s had rear wheel steering lol nothing new and steer by wire isnt required or nessasary for a vehicle. this truck would be alot better if it was a hybrid so it could actually tow 500 miles unlike false advertisement from 2019. this truck is a gimmick period obsolete and outdated.
Redundant and sometimes triple redundant on everything.... Except power! No mention of a redundant 48 volt power supply.
@@DavidJohnson-tv2nn you sound like an expert. What redundancy would you expect to see?
@@tomz1364 I'm not an expert. But... On something as critical as steer by wire, I would like to see end to end redundancy, including power. That means a backup battery separate from the 48 volt battery and separate from the car's main battery. In a different location in the vehicle. These systems should be completely failsafe. At least before I would ever consider buying one. Also... I would hope that if there is a failure, the computer doesn't allow someone to continue driving the car. 50 to 100 miles to get home and it should shut down until the problem is corrected. Again, not an expert, just my opinion on the subject.
Very nice that the logo of ZF (Zahnradfabrik Friedrichshafen) from Germany is on the case. This confirms, once again, how self-confident ZF is, that they are able to enforce their logo there at Tesla. This also shows that Tesla simply uses the innovations of Tier 1 suppliers for many components.
And proving Sandi is all confused when he keeps using the term "vertically integrated"....tesla is far from it. they are an assembler like all others, that get parts from thousands of OEM suppliers. sandi is so confused, so many times. He thinks if he pretends to know stuff, and keeps the same lies, like a politician, it becomes the truth. Wake up, 70's porn mustache
In 1988 a friend bought a Honda Prelude with 4 wheel steering. Not steer-by-wire, but that thing was fun to drive. Thanks for the descriptions and views of the beast's steering.
Do you remember if that year prelude has the long steering driveshaft to a separate rack in the rear? I know they started using electronic rear steering on the preludes but can't remember which year
@@dd89210 That I don't know. It was a new 1988 .
@@dd89210 Electronic 4ws didn't come until the 4th gen Prelude.
@@ShaunRF ah that's right the ugliest of the preludes
Also, Armin has been working out, holy smokes!!!
I think he must be a distant relative of Arnold Schwarzenegger or something. He's got the accent and everything :)
Just awesome presentation. Keep it up Sandy. We're counting on you!!!
More essential info , any driver should be interested in ! Good work Sandy , I live for this .
Impressive tech - thanks for the tour guys. Couple thoughts come to mind on truly redundant systems - I would want those ribbons routed differently through the vehicle structure vs side by side, and I certainly wouldn’t want them terminating in a common connector. It would be interesting to know if that conversation happened during the design phase - especially on the common terminal and if someone pulled up data to say the chance of failure at that point was so small it wasn’t remotely worth designing two different interface points.
My thoughts too - using a common connector means the redundancy isn't there. Additionally, in both tear-downs I've seen, there seems to be only a single sensor at the end of the steering shaft measuring the driver input, so if that's correct that's a huge gap in the system's overall redundancy,
It's a single pair that allows bidirection ethernet data transfer. The cables are flat to allow better routing. The other motor will have an independent pair. The tie breaker will have another independent pair. Command signal is triple redundant, drive motors are dual with a fail safe design. ^guessing
@@christophercullen5256 They only mention the one pair of ethernet cables. Seems like there's some redundancy, but it only extends as far as the steering motors and sensors on the rack, not on the cabling / connectors or steering input sensor reading driver inputs. I'd love to have clarity on this, but thus far it seems and looks only partly redundant.
@gruppefbc I think Sandy got caught out talking electrical stuff. Where is the steering wheel, where are the front drive units (close), why is that ethernet cable several meters long with a single connector? I think it's for the back wheels.
@@christophercullen5256 That's certainly a very plausible theory of the cabling being for the rear motor. Still leaves questions unanswered though, especially the key one of if there is any redundancy on the steering wheel input sensor. If there's only one sensor, that's a huge failing of a key safety aspect of the system.
excellent in depth overview. thanks
Thank you!
Thanks! Difficult topic, feel like I'm starting to get it, much appreciated
Really enjoying these CyberTruck tear downs. Nice
Does anyone else want to see Armin and Jordan standing next to each other, or is that just me?
What about Sandy and Armin: is Sandy short and Armin tall? Or is Sandy normal and Armin a giant?
Armin is what Jordan Arocha would look like if you put him in the Captain America machine!
Lmaooo
Grats @TeslRebuilders, happy that you’re getting something you’re so excited about. People hating on Tesla cause it’s en vogue while ignoring the content of the videos they post on really need to re-evaluate their priorities in life. Constructive criticism is one thing but being an ass just for the sake of it or trying to make people feel bad for what they choose to do with their money is such a waste of energy, go focus it on something constructive.
Great show/ report - Thanks
It’s more ZF steer by wire, than Tesla. They build these systems for years. Don’t understand the hype. The problem is not steer by wire, which is old technology, but need for a backup steering system outside the US.
re: "Don’t understand the hype." A: well Ego and regardless of where the Stock is at...? the "scam" of the Jordan Belfort Pump And Dump must continue unabated.
It's all ZF and third party suppliers, Tesla couldn't do shit without those innovative giants.
You don't understand the hype.
It looks like center to lock is a bit less than 180 degrees. Therefore lock to lock is about 330-340 degrees, not “less than 180”
Thanks for video!
You're very welcome!
That little lift is pretty neat seeing the safety latch automatically engage when it isn't moving.
Isnt it better to make the cable separate? What if something happens that the cable is damaged. If they are so close together they can be both damaged
I have been begging for a wiring episode. I would assume elon wouldn't want it because everyone is kinda trying to catch up to elon, but yeah, we all got questions. they could separate the cables, so it runs on either side of the battery, so one gets damaged, it uses the other....
And both cables connect to the same point, a little corrosion there takes both out. Not really a triple redundant system.
And what happens if you lose power? Either through battery failure, accidental/intentional power off or connection failure. Is there any sort of mechanical steering wheel lock on Teslas as there are when legacy ignition keys are removed?
@@GntlTchNope. Check Out of Spec reviews… they tested and answered your question.
A rat would chew both cables ar once
Great video. Thanks.
Armin can do this All Day 🛡️⭐😅
The gearbox shown at 8:18 is clearly a worm gear driving a wheel which is on the pinion shaft. There might be planetary reduction as well, I suppose.
That is what it looked like to me, too.
100% - no planetary drive required for the ratio between motor and rack. That is a worm drive connecting motor output shaft (worm) and pinion (connected to worm wheel).
About Sandy's last ppoint/ sentence, El on just reminded us in the Earnings Report, "Tesla is a Technology Co."🤔..😆
Great series!! 👏👏😍😍
Thank You ...once more!
Confused by REDUNDANCY terminology. Also had same issue with the Boeing computers description I have seen elsewhere. For instance you showed what seemed to be a twin cabled lead and called it double redundant. Is this a difference between American English/Math and English English/Maths? In English English a double cable would simply be called a (single) redundancy. A double redundancy (two redundancies) would be three cables. Likewise "triple redundant" system would be four systems. Or did I not see/hear all the redundants being described?
No, it's not a region difference, it's just poor understanding of the terminology.
@@brianb-p6586 As in my poor understanding or various engineers on KZhead? My UK 1980's training (and since) was very definite that a single redundancy consists of two systems, and so on.
@@johnpublicprofile6261 I was referring to Sandy's poor understanding of terminology.
Not quite sure where this claim of triple redundancy is coming from. There's either some complete ignorance of the meaning of "redundancy" at Munro's shop, ot there's some clever marketing (lies) coming through back channels from Tesla to Munro.
Any OEM that isn't paying Munro for their teardown analysis will be the first to go bust. BZ to SM and his team for educating the masses. Well done folks from all of us in Canada. I cant wait to take delivery of mine. Cheers
Tesla don't supply vehicle to Munro. Munro buy the vehicle & sell the reports to pay for the vehicle.
I think Sandy remarked on this a few years ago. Only the Koreans and Japanese were paying him for the analysis (that or the USA OEMs were paying but not making any of the recommended changes). He said that Tesla was the only OEM that implemented all of the recommended changes (or maybe most? ...I think he was talking about the Model 3 ...my brain is a little slow this morning lol). It is very hard to make changes for domestic (USA) OEMs especially if the changes eliminate a union job. (I lived in NE Ohio and had relatives working for Delphi & Lordstown in management and on the line ...crazy stories!)
Electric steering has under development by OEMs for over 2 decades. I’m not seeing much unique here, only the 48V power.
@@boredKiwi Yes, you said it. In development in last 2 decades & still under development. What a winner!
Do you really think the OEMs do not themselves buy and look at cars from competitors.
Sandy and Armin Rock!
Looks like the Car Wizard is moonlighting at Munro and disassembling the Cybertruck!
Weeeezard
Standing next to Sandy this guy lives on an entirely different planet
Hey Sandy their is a little Easter egg for you when you open up the steering feed back actuator and look at the PCB.
In control engineering, the arrangement is called 2oo3 ( 2 out of 3majority voting ) system....not triple redunandant. Triplr Redundant to a SINGLE control unit is adequate to guarantee an acceptable level of safety such that any fault will automaticallly force the car to go into a safe state to protect the car and its occupants from an accident.
My guess is that the third sensor is not for safety or redundancy. Odds are that ZF/Tesla went with two servomotors on the front steering rack in order to provide enough steering power to steer this giant tire/wheel combo in certain off road environments. Anyone that's ever worked on a dedicated offroad racing truck would understand this. I believe the third sensor is for power management between the two servomotors since they have to run synchronously all the time. This is not a design for redundancy.
I like the video/audio of the guys doing their work. The “reaction video” thing of you all taking apart the different major, minor and sub assemblies would be neat along with the usual videos where you discuss what you learn after studying the goodies. Just a different kind of content maybe? Anyway, love the way you all are having a blast with the CT. Mine is coming in about a year or so lol I expect there to be a few significant improvements vs this tear down victim.
Airplanes have redundancy on all crucial systems, but Cybertruck doesn't have redundancy on power for example. So if power fails, you will lose steering. There's a reason why other brands still have mechanical backup on drive by wire systems. Also the amount of electronic overhead on this system leads me to believe it's not as cheap or as light as its mechanical counterpart. As far as boats, we've seen what happens when they lose power, they collide into bridges because they lose steering, for example.
Can someone explain what the purpose of the redundant ethernet cables is when they share the same connector? I would think you'd want redundant connections as well. What am I missing?
PARTS Reduction. the BEST part is no Part.
@@markplott4820 @sphigel1 it's because they have two sets of pins in the same connector. Connector probably ridiculously robust. Really impressive engineering, both design and DFM.
I can - it is BULLSHIT. That connector connects front zonal module and rear zonal controller to RWS INSIDE the vehicle. The flat ribbon cable and this connector are NOT designed for environmental conditions in the "engine bay". You can see the male connectors on the SbW rack actuators (split into BIG power and communication seperate). Each one - no way that blue one is connected to the SbW system directly! I also highly doubt it is 100% ethernet. And redundancy terminology is also mixed up in the whole video. The power is coming from a different wiring to the power packs (each probably >1kW, you don't run >20A @ 48V on that tiny ribbon cable!). And then they get the steering commands from another gateway/ethernet switch connecting feedback actuator (driver steering wheel) and the SbW gear.
It's MUSH engineering, and Sandi is clueless. He's always knowing more, just ask him. and he has been impressed by a matchstick, if it had "Tesla" on the box
@@cengeb - SANDY knows MORE about TESLA , than he is Disclosing. MUNRO makes Business of SELLING Teardown reports & vehicle COSTING. I bought a $5 (FULL) Report from MUNRO on the BMW i3, I was thinking of making a Affordable city car , at the time. If I were Stranded w/ just a Matchstick in a Foreign Country , I would make it back , with $1 Million in my pockets. DONT underestimate what Match can do.
That etherloop wire+connector looks interesting. First of all, the cable is not twisted pair like we're used to seeing with Ethernet.That seems important, since twisted pair and differential signalling is the way ethernet builds resistance to interference. I would love to know how this system was made resistant to interference, or if Tesla perhaps found that twisted pairs are not needed and differential signalling works just fine over this flatcable design. It would be helpful to know how this cable is routed in the actual car. Second of all, I would be interested to know how many contact points are present on the connectors.
That’s such an amazing technology
Can you guys measure any response delay? Probably just the flex of the rubber, but the sound of the sand under the tyres definitely is delayed a little.
So the Tie Breaker sensor would be polled and if it was significantly out of synch you would get an error code to have the car serviced soon, but if one of the main actuator position sensors failed, then I wonder if it would disable that actuator and then rely on the 2 remaining position sensors in a limp mode to get the car to a service. Or perhaps the 2 good sensors could operate both actuators and operate more normally with the error code. Triple redundancy is pretty cool.
I think it is actually just continuous. By that I mean every input is polled in real time--probably more than 100 times per second--and whichever two sensors are closer to agreement for that particular polling event are assumed to be correct. If there is a repeating discrepancy by the same sensor where it is the odd man out over some preset time span, then the system will flag it as defective and signal a fault that needs attention.
I suspect that each sensor module actually has two sensors so that if a sensor fails it can be detected and ignored. This is how SpaceX designed their triple redundant system.
Unless this system is a poor design the sensors and actuators as independent. They're packaged together for convenience. What happens when a sensor fails is up to the software. I can tell you what I think makes sense. Read all 3 sensors all the time. If any sensor disagrees or fails to respond we still have enough information to drive the truck but should a 2nd fail we don't. That could be very bad news so the truck needs service. *An error code alone would be a bad idea.* What the software allows the driver to do is up to Tesla. If it were an airplane we could continue to fly with 2 and even 1 sensor. With the car one has to allow the car to safely stop. We don't want people driving around with less than 3 good sensors but we don't want to endanger them by forcing their hand at an 'inconvenient' moment. There are both engineering and legal issues here.
That sensor is actually a plastic box containing two completely independent sensors with two independent circuits. Which means that the two sensors are actually quadruple redundant. This way they can look at each pair independently and when one is in agreement and another one is also in agreement but slightly different they can measure that there is a slight difference but if it fails in a way where one of the four sensors is significantly off It can ignore it and make an assumption about which one is bad. There's a lot more information you can get.
Unfortunately, in the software world we see different design considerations that people mistake for triple redundancy. Rather these big clusters can operate on three systems, but is not triply redundant. Instead it supports up to hundreds of systems, but locks when there are just two. That's because the chosen failure mode is different because people don't die if the server goes offline.
I saw a Cybertruck at their King of Prussia mall showroom. Loved it. Finally had one pass me on the road in my Model 3. Was that you Mr. Kelce? Damn it is huge. I felt like I was driving underground .
Heads Will Roll Amidst a chaotic month for Tesla - even by its continuously plunging standards - Facebook cofounder and multi-billionaire Dustin Moskovitz has made some pretty dire predictions for the automaker, accusing it of committing "consumer fraud on a massive scale." "This is Enron now, folks," Moskovitz wrote on Threads, referring to the corporation that went bankrupt in 2001 after it was exposed for one of the biggest accounting frauds in history. "It may keep going, but people are going to jail at the end." His concerns stem from a graph Tesla shared to mark a key milestone: one billion miles driven using Full Self-Driving, the company's highly fraught advanced driver assist system. He then compares it with a new graph released during Tesla's latest earnings call - an event that came with its own eyebrow raising moments. The point of the side-by-side is this: according to Moskovitz, the automaker is wrongly recognizing its deferred revenue - revenue for a product that hasn't been delivered, like an annual subscription fee - as earned revenue through the wider release of its Autopark feature last month. This is a sketchy move, Moskovitz claims, because an earlier version of Autopark was already released with FSD years ago, resulting in inflated numbers. "The data is presented in fraudulent ways, and it doesn't say what they claim it says even when they make it up," he wrote.
Cheers 👍💪✌
Next level engineering. Nothing but minor tweaks from lessons learned for the Gen 2. Incredible design.
lol, no
I truly think Armin is secretly press benching the Cybertruck between breaks
Hey guys, I'm glad you're impressed with this technology... I was hoping you might want to examine the ability, if Tesla has allowed, to convert to right hand drive fur us down under!!
Sounds like the 2 mic audio tracks weren’t synced in the edit hence the echo/reverb when they both talk and both tracks need to be unmuted for those sections
Sandy Wishing you a quick recovery for your hand :)
Tesla's signature steering creak 🤣
Great work guys!! Thanks for everything!
Thanks for watching!
Wow this is the automotive technology of the future. Very exciting. Also sounds expensive😮
At first I thought they shrunk Sandy
Brilliant! 😂
My 1994 Stealth RT/TT has active all wheel steering and it's 30 years old. Porsche 928, BMW 850, and even some Honda Preludes all had it in the 90s.
Thanks for your information
Were they steer by wire, or all mechanical?
@@1flash3571 Makes no difference if it works
Yep they called out the other types of 4w steering in the video. Hydrolic, mechanical etc.
928 is passive system where wheels move to direction providing understeer. There is one extra rubber joint in lower control arm. When brake is applied wheel turns inwards instead of outwards as in usual suspension arm. There is no rack or any other extra control mechanism in it. Prelude, 850 etc. were more sophisticated systems back then.
Sure wonder how that would function driving on ice or snow, or a mixture. Please test it on ice, since where it used to be snow, it is now ice. Keep it up Munro!
AWESOME
Sandy was right; the next software update will increase the steering angle of the rear wheels. Yes, ZF is developing the Steer by Wire system for the CT together with Tesla. Tesla works with many hidden champions in Germany, but of course, you know which Tier 1 and Tier 2 suppliers Tesla has.
crap!!!! didnt tesla made the steering angle up to 10 degrees+ from factory!? why didnt tesla made the locking diff also available?! those are just lame excuses! the very old chevy quadrasteer had a significantly much bigger rear steer angle from factory.
ZF is the worlds largest automotive supplier and makes parts for literaly all manufacturers, rear wheel steering is also been in development with all manufacturers too! mercedes and other manufacturers have much bigger trucks that offers up to 3 or 4 steering axles.
Tesla had bought RIVERA tool & die , and GROMAN Engineering many years ago.
@@alanmay7929 Bosch is the largest, whilst ZF is big, Bosch is bigger
@@cengeb zf is both
I would say the steering system has redundancy with parity check vs it being triple redundant.
I was hoping for a teardown of the front rack to see how the two drive units deal with failure modes. Clearly there's a worm and wheel pair turning a pinion driving the rack on each side. Also the description of the electrics sounds a bit presumptive. I mean are they really using ethernet packets for realtime control as Sandy suggested, or was that just a guess? Hook it up on the bench and find out. This is the 'technology' we're told is so great, can that not be demoed? Thanks for the video!
Another ZF symbol under the encoder casting at 9:01
It's all ZF, or other major suppliers, Tesla would never be able to develop those things on their own.
Is there only one steering input sensor??? If so, this system has zero redundancy.
All of it is bs , this will get a massive recall the moment the first one broke and made a massive accident.
Pleased to see Tesla cooperating with ZF
FMEA on that must’ve been fun!
Monro is a national treasure. Thank you for educating the masses on the innovations of Tesla and all EVs.
All I can say it I picked my CyberTruck up Tuesday and it is awesome!
give it time, it will have issues, major issues. What's it like to be a test guinea pig?
@@cengebwhy you speaking with hand rubbing.
when wrecked cybertrucks start to show up, sim racing community would be in joy for steering assembly. it would be a great base for sim racing.
Or they could make a sim wheel.
Being able to adjust the steering ratio sounds like a dream. There are plenty of times I wish my truck had a quicker ratio but I'd have to somehow find a steering rack that fits my truck and is quicker, so basically it ain't happening.
million dollar question: How is the 48v power supply redundancy / backup handled and where? A total loss of 48v power is going to be a problem! Does the rack still have mechanical self centering, ie is the motor drive ratio and motor friction/cogging low enough for the castor angle to push the wheels back to centre in the case of a complete loss of 48v power, or can the vehicle use brake bias to steer in extremis?
you aren't the first person to think of that. Maybe go watch more tesla vids. Tesla has two electrical systems in each car. The main battery winds down, and it slows you down. Eventually, when the battery is 1% it doesn't let you go faster than 1 mph. Then it shuts off. You still have lights and steering powered by the backup battery system.
@@davidanalyst671 no. i'm not talking about a HV traction battery discharge or failure, i'm talking about redunancy on the 48V battery and asscosicated electrical distrubution system. I'm sure the SBW meets ISO 26262, i just would like to understand how that is achieved with respect to the 48v power architecture. I'd immagine it is furnished through very careful fusing and discretisation of dual feed paths,using both the 48v storage battery and the HV-LV DCDC to provide seperate and non-cascadable redundancy!
seems , you haven't EVER driven a TESLA . total FAILURE is Exceptionally RARE.
@ MunroLive how can "steering by wire" be TRIPLE redundant, if we could smash/disconnect SINGLE Ethernet-loop connector.. hmmm ?
My biggest question: Is the toe in angle controlled by strictly mechanical connections? Or is there a dynamic adjustment to the toe-in depending on what the rear steering is doing?
Strictly mechanical. The difference is how the pinions are driven. The rack is the same.
This is very interesting. On the front steering motors, how much is steering performance impacted by the the loss of one motor? Also, is there redundancy built into the angle sensor for the steering wheel? That is one of the only items you didnt mention redundancy on. I am not a big fan of the dual Ethernet wires running right next to each other. It seems that is one is severed then there is a high likelihood that the o the would be damaged.
enough , to be Safe & in Control, pull over side of Road.
Is it really wise physically running the 2 redundant data cables attached together? A physical event that damaged/severed one cable would likely damage/sever the other since they are attached. The cables should be separated and run down different sides of the front chassis for safety. Just seems crazy to me for a system that’s supposed to be redundant for safety.
If you've had an impact so severe that those cables are seriously damaged, that would have completely destroyed the steering shaft in any other vehicle.
They aren’t attached, they do run independently, Sandi holding them together is not the same 🙄
@@fredbloggs5902 There’s only a single connector on each end of the cables, they do appear to be attached/run together.
@@Weezedog Now go lookup the published wiring loom of the Tesla 48V system, you can clearly see everything is duplicated.
@@otm646 honestly we don’t have an idea exactly where/how the cables are run through the chassis so no idea how susceptible the cables are to pinch/crush/rubbing damage.
This explanation was way convoluted I feel. My try: 1. The complete turning radius of the steering wheel is 200 to about 240 degrees. 2. at slower speeds small motions of the steering wheel result in big motions of the wheels. 3. at high speeds bigger motions of the steering wheel lead to smaller motions of the wheels. =)
Sandy’s videos are for semi informed people in the automotive industry. It’s going to sound complex and dragged out. For a lot of us we like to see and hear all the details, not just the basic information that’s been said by everyone.
nothing special actually!
@@Zeesneakyninja No, it's just incoherent. It's neither succinct nor detailed.
Please, please, please... someone at Munro's shop enlighten me, and the rest of the world, why they think this system is "triple redundant".
I don't understand how you can call this system "triple redundant". It is NOT triple redundand at all. It's not even close to dual redundant. In my experience in the aerospace and aviation industries, this is not even remotely redundant.There's multiple single point failure modes. First is steering sensor and feedback motor at the bottom of the steering column, then the rear steeing drive motor, and unleess there's full redundant circuitry in the control unit, it is also a single point failure component, especially if the redundant circuits share a common enclosure and electrical connector. As far as high a reliability design for such a critical function, this is a haphazard and dangerous approach. Even the wiring cable you displayed as "redundant" is a poor design. Having boith cables bundled together, and both cables terminated in a common connector fully defeats the propose of redundant conductors. The only part of this system that should have "triple" associated with it is the sensors on the steering rack that tell the controller when one of the front steering motors craps out. The list of single point failure items in this system is frightening. There is only one reason for the 48v bus and the ethernet data speeds; this grossly complicated "drive-by-wire" system. 48v is required for the peak impulse power demands of operating 3 steering actuators, and the high speed data is necessary to reduce latency between the steering wheel and the steering rack actuators. Other than that, it's just overkill that complicates supply chain problems for automotive electrical system suppliers.
Despite the description at 4:29, four wheel steering is not new. Active 4WS still isn't common, but it has been around for many years.
How about a bit of grease in those rusty wheel holes. Great! Thanks!
On ehuge benefit of by-wire steering is the ability for the system to decide what steering roadwheel angle to apply no matter what the driver input to the handwheel is. The biggest problem when calibrating a dynamic stability control system is drivers who "wang" the handwheel all over the shop, upsetting the system. With by-wire steering, you can perfectly control vehicle yaw with a roadwheel steering input as well as, or in preference too, a brake yaw application. Add in machine vision and lidar, and you can finally break the age old problem of drivers simply getting target fixated on the thing they are about to hit, and as a result hitting it. In advanced driving we teach "look where you want go, not where you don't want to go" but for most drivers, and emergency is so rare, unfolded quickly and un-expectidly, and as a result, a lot of fundamentally avoidable (through handwheel inputs in conjunction with braking) are not avoided at all....
Wenn Du sowas willst oder brauchst, ok - aber ich schalte im Winter je nach Straßenglätte und Schneelage sogar das ESP AUS - aus dem einfachen Grund, weil es hoffnungslos überfordert UND eben viel zu langsam und träge ist. Bei sportlicherer Fahrweise, ist das System sehr schnell überfordert. Probiere es mal aus, ein außer Kontrolle geratenes Auto MIT und dann OHNE ESP wieder einzufangen - dann weißt Du was ich meine. Bei mir, war es also genau anders herum, dass das "überforderte ESP" ständig und verspätet MEINE Lenkkorrekturen dann praktisch zunichte gemacht hat. Man spürt dann regelrecht, wie das ESP mit 0,5 Sekunden immer zu spät eingreift.
What's the real benefit of having drive by wire? Because now tesla has to install two electric motors, where it would be cheaper to install a manual steering wheel shaft.
Since it can drive itself (potentially) it needs most of that, anyway. This way, you lose the weight and collision risk of a steering column, and you can do the variable steering ratio thing.
@@geirmyrvagnes8718 But does it save money? I know tesla is about that.
@@xxZerosumxx Presumably. Just think about manufacturing. Bolt in the assemblies and plug in connectors. Done. Probably very automated. In addition to not having to pay for a steering column with linkages and going through the firewall with a big movable thing. The other parts are mostly needed for self-driving, so you can't delete them.
My 1st truck didn't even have power steering and it worked excellent.
Yes and it polluted causing global warming and bad air quality
And didn't cost as much to purchase or maintain nor weigh as much
And? It probably didn’t have airbags, anti-lock braking or seatbelts either 🙄
@@fredbloggs5902 And death rates are no different
@@MegaWilderness - Well, the dead don't complain about the lack of safety systems!
Armin seems to have that young immigrant energy that Nikola Tesla himself had, and he seems to understand Tesla’s game plan in innovation well. Sandy, more with Armin, please.
Smile for the camera 😃
Beautiful system, yet very expensive. I'm surprised Tesla adds the complexity and cost of a rear wheel steer system, it kind of goes against "the best part is no part".
You don't understand "the best part is no part". Your saying the best car is no car.
re: "I'm surprised Tesla adds the complexity and cost of a rear wheel steer system" no worries, be less surprised as the CT's wheelbase is a whopping 143 in. for reference this is 7 inches longer than the RWS equipped Hummer EV, but 3 inches shorter than the wheelbase of the RWS equipped Silverado EV. Tradesman and Contractors already struggle to get in and out of tight-ass Home Depot parking lots with the existing wheelbases of their Crew Cab gassers and Duallies.
this , is just FIRST production version of Cybertruck. many MORE Iterations , coming soon.
Could you do a tensile test on the door? I really want to see how strong their custom alloy is. I'm still betting 1'690 MPa of tensile strength and 25% elongation at break, that would make it one of the toughest steel alloys ever made.
toughest steel aloy ever made?! are you high on something?!
@@alanmay7929 Stainless steel is known for being tough, that's why it gets so hot during machining. Besides you can tell at the sharp angles with no orange peel that's it is very ductile for an alloy with this level of strength.
@@johntheux9238 lol!!!!!!!!!!! keep that lie with you!
@@alanmay7929 this guy knows more than you. You’re making a fool of yourself.
@@brendanmeyler1641 yeah "Einstein" lol!! he knows literaly everything wow.....
what are all the silver and black dots on the parts for? thx 4 the great videos.
They are little reflector stickers applied to the parts prior to 3D scanning. They are being put on by someone at Munro's shop.
@@Thegrimmechanic cool, thx
Wondering about getting one of these aligned.
Fwiw my 08 Silvy doesnt need alignment after all these years 😂 and ball joints arent greasable even
The same system is used by rack and pinion cars with manual steering. This one is an automated version so no diff.
AUTO alignment.
Here's a question: would the Steer-by-wire system be able to perform what amounts to "dynamic wheel alignment"? I would think that the CyberTruck could perform micro-adjustments to the wheel alignment as the vehicle is moving to minimize rolling resistance. Maybe this has been mentioned at some point but I have not seen or heard anything about it.
Not sure what you mean. The only parameter a steer by wire system could change is toe in. And for that it would need a split rack which doubles the number of motors and sensors a much more complex design. Or am I in left field.
No. You can clearly see the steering rack geometry is pretty standard with the usual way of adjusting alignment manually with a spanner. Both motors work together to drive the same rack. There are 2 for redundancy/safety in case one fails.
@@danharold3087 - it was just a thought, apparently not a terribly good one, but in my defense I had not had my morning coffee so I blame caffeine deprivation. Thanks for your comment!
@@fredbloggs5902 - Understood. Thanks for that clarification. As I mentioned to the other commentor, I believe caffeine deprivation led to my wayward thought. Cheers!
Q: Here's a question: would the Steer-by-wire system be able to perform what amounts to "dynamic wheel alignment"? A: no, well not at least with this system in the way it's currently configured, but that IS an interesting thought you have as it would simply have to be configured in the way Porsche ALREADY does it with the Rear Wheel Steering option available on the 911... that is to say, the current generation 992 (by virtue of being a rear engine mated to a transaxle) is forced to implement the use of Rear Steer by way of 2 separate actuators (1 placed at each wheel) that are not connected as would normally be with a standard EPS rack, therein technically they are able to move INDEPENDENTLY of one another for optimal geometry (think: Ackerman Steering)... to that end your idea of Dynamic Wheel Alignment DOES in fact exist at least in prototype form, yeah the mighty VW Group just debuted it 3 months ago iirc on a Lamborghini Huracan and it's called called AWC (Active Wheel Carrier). that's right, sorry Tesla but you lose again, unfortunately your CEO's Ego is simply not big enough to overcome the DEFICIT Tesla has to an OEM like VW who actively participate in Motorsports and Racing. again i repeat: "Anytime you win Leman 19X since 1970 (mind you someone hadn't even born yet) you learn things that the laymen and pretenders DO NOT..." (my voice) kzhead.info/sun/Z6-bg6lqm4VuYGw/bejne.html
Have we worked out what happens with the steering if the vehicle no longer has power? Will I still be able to steer the wheels to safely manoeuvre the vehicle off harms way? I think this type of situation is more likely to happen than having triple redundancies for system failures.
You have a main battery and an auxiliary battery. If the main battery fails then the vehicle has no motive power but the auxiliary battery can still drive the steering system. If Aux fails then the main battery can provide power. If both fail then regenerative braking can provide emergency power.
they have backups.... but when you run out of juice in the main battery, it slows, slows, and slows even more, and before it completely shuts off, it makes sure you are stopped. There are vids of people running them out of power
It can only steer if it has 48 volt power. There should be redundancy in the power supply; perhaps Munro can cover that in a future video.
@@brianb-p6586 Now I am curious. What is the voltage of the auxiliary battery. Is it 48V?
@@kazedcat yes, the low-voltage battery in the Cybertruck runs at 48 volts, nominally.
What happens to steering in case of a power issue? If the low voltage battery malfunctions while driving, is there any backup power source?
Today featuring a bigger Jordan!!!
All rear-wheel-steering is steer by wire.
All current rear-wheel-steering is likely steer-by-wire, but there have been mechanical systems.
Imagine being a Ford F-150 engineer watching this video... it's like me looking up at the summit of Mount Everest from the base camp.
Ford is one of the signers of the steer by wire standard. Now we will see if Ford puts it in their next generation vehicles.
None of this is super difficult, there just hasn’t been a need, and no R&D justification. Also, the 48v system helps tremendously for this, so now that suppliers know how to work with 48v, it’ll help
Don't think the F150 customers are ready for that. And as a former mechanic myself I also still prefer normal steering. I'm just seeing alot of potential problems to be honest. These cars are gonna be a nightmare to diagnose and repair in a few years. Or it's me who are to old..
they probably have some great engineers who are handcuffed by the penny pinchers and executives with no vision
nonsense!!!! they dont need all this crap! why would they waste money to put on a big truck that is used on massive american roads?! the bigger ford f250, 350, 450..... have solid rear axle to tow more, make modifications super easy! the cybertruck is garbage compared to any ford body on frame period!
is there a double redundancy on the steering angle sensor on the steering wheel as well?