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Is Model Steering fully electronic or is there a steering shaft?
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A few points, first, the only way to have a hydraulic power steering system would be to install a small ICE to power it. Second, many ICE's are moving toward electric assist. The reason is they’re mechanically simpler; they’re touted as more reliable, they weigh a lot less, and because electric assist only uses energy when you’re turning it boosts fuel economy. Third, my first car didn't have power assist, outside of a parking lot it is really not that hard to drive.
Babylonfive
Power12
The solution is easy. Just get yourself a 1965 Mustang without power steering and practice.
I did that for a while (Red 65 Convertible) but had to sell it to make room for Nikki. <sigh>
Technically, you can use an electric motor to power a hydraulic pump - you don't need an ICE. In fact, the brake system in the Model S is an electric power-assist hydraulic brake system.
I haven't noticed it either. That's not of function of the steering being electric because the Prius doesn't have a dead spot. I guess it's just how Mercedes wants the steering to behave.
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The solution is easy. Just get yourself a 1965 Mustang without power steering and practice.
I've had several vehicles without power steering. The main effect of no power steering is that the steering wheel is larger.
Most manufacturers actually build the "dead spot" in as a feature not a flaw. This is to keep a car's steering from feeling "darty" or "twitchy". By having a dead spot or "slop" with the steering on-center (no steering input) you can move the wheel slightly during normal driving conditions and not have the car make sudden or dramatic movements. Typically, OEMs are moving to variable steering ratios too to give more feedback as you dial in more steering angle.
The MS does have a slight "dead spot" when the wheel is on center to prevent the darty feeling. Eitherway, I feel that Tesla got the steering spot on with the MS despite being an electric setup. The car delivers good feedback during spirited driving without being over communcative during normal driving activities.
Disclaimer: Steering feel is VERY subjective and based upon what YOU want out of it. You just have to drive one to get a good feel for how it fits your tastes.
Sorry to everyone commenting, but here are the facts, with all due respect. The definition of progress when it comes to technology, specifically cars and vehicles and things of that nature, is the elimination of steam era mechanics by replacing them with software and electrically actuated systems.
Multirotors are one such example. Eliminate the complexities of a helicopter and replace them with software and brushless motors. Even conventional helicopters are looking adopt fly by wire technologies in the near future.
A mechanical system has one point of failure. It is very easy to incorporate redundancies into electromechanical systems as well as electronic/software controllers.
I once had a power failure in an old car I had. The steering wheel locked on me and I could not steer the vehicle, even with that big iron shaft connected to the steering box.
They will incorporate a steering shaft for awhile to appease the late adopters, then it will be completely eliminated.
When was the last time you stopped at a green light to make sure the cross traffic indeed had a red light? Did you trust your life to those infernal contraptions known as computers and wires? Did you fly through the green light like a complete madman? I did.
Multirotors are one such example. Eliminate the complexities of a helicopter and replace them with software and brushless motors. Even conventional helicopters are looking adopt fly by wire technologies in the near future.
A mechanical system has one point of failure. It is very easy to incorporate redundancies into electromechanical systems as well as electronic/software controllers.
I once had a power failure in an old car I had. The steering wheel locked on me and I could not steer the vehicle, even with that big iron shaft connected to the steering box.
They will incorporate a steering shaft for awhile to appease the late adopters, then it will be completely eliminated.
When was the last time you stopped at a green light to make sure the cross traffic indeed had a red light? Did you trust your life to those infernal contraptions known as computers and wires? Did you fly through the green light like a complete madman? I did.
mandersen
Member
Check again the 2014 Infiniti Q50S was the first steer by wire car.
Infiniti's New Steering System Is a Big Step Forward—Unless You Love Cars
stopcrazypp
Well-Known Member
Is the steering wheel ever locked on the model S as in most cars when the key is in the off position? Also, is there less wear and tear when you place the steering assist in sport mode or does it matter?
gartz
Member
I had a malfunction in the steering motor at the first day I got my Model X. I got my car at the Tesla dealer, drove home. Next day when I pressed the break, the car start the powering up and display a steering malfunction in the screen.
It was possible to move the wheel, but it was absolutely heavy! In an emergency situation I would be able to handle it, I don’t think anyone would.
I texted my dealer and told about it, while waiting for the response I restarted the computers, then turned off the car, then left the car and came back an hour later, it went to the powering up process again and display had no errors but an alert to service the car.
After two weeks in the service my Model X was returned with a new electric shaft or something like that.
So far no issues besides I think my Model X in comfort mode is heavier than others that I drove. But still light enough to not stress much about it.
It was possible to move the wheel, but it was absolutely heavy! In an emergency situation I would be able to handle it, I don’t think anyone would.
I texted my dealer and told about it, while waiting for the response I restarted the computers, then turned off the car, then left the car and came back an hour later, it went to the powering up process again and display had no errors but an alert to service the car.
After two weeks in the service my Model X was returned with a new electric shaft or something like that.
So far no issues besides I think my Model X in comfort mode is heavier than others that I drove. But still light enough to not stress much about it.
I had a loaner S once that lost power steering. Very hard to turn but I did drive it for a day (Home, work, Service Centre). The way steering geometry works is that SAI, in combination with caster, is used for self-centering. When the wheel is turned, the tire/wheel/bearing assembly rotates around the steering axis lifting the vehicle up because the SAI angle and the camber angle meet below the ground (if the camber is positive, they may never meet if negative). You're literally raising the vehicle's front corner by turning the wheel. How much lifting has to be done depends upon the distance between the camber angle and the SAI angle where the angles intersect the ground. (further apart means more lifting). Caster has little self-centering effect at low speed, but the effect increases as speed increases, while SAI is consistent regardless of speed. Car manufacturers balance these two angles to achieve the desired self-centering characteristics. There is also centre-point steering. In this case the SAI and camber are always aligned, so the distance between the two angles at ground level is zero. However, using this method means the brakes need to be mounted inboard because there is no room for them in the centre of the wheel because that's where the ball joints are. Doing this reduces unsprung weight and decouples the brake disk diameter from the wheel diameter, but also reduces front (frunk) compartment space. Examples of a centre-point steering cars are the ID-19/DS-21 family.
I haven't read this whole thread so maybe someone has already gone into this, but to compliment jerry33's post, here're the mechanics.
There's a flat rack with gear teeth in one side, and each end of it is connected to a tie rod end, which in turn connects to the wheel support casting on each side. The steering wheel shaft extends down to that rack, and has a pinion gear on the end. This is the solid mechanical link to steering.
For power assist there's an electric motor with a pinion gear also on that rack. There's a position sensor on the steering wheel shaft (above your feet) which feeds the steering wheel's position to the ECM, giving an error between where the wheel is and where the rack is, so the motor moves to correct that error in real-time. That 12v motor is the power assist.
IOW it doesn't matter all that much whether you have it set to Sport mode or not.
There's a flat rack with gear teeth in one side, and each end of it is connected to a tie rod end, which in turn connects to the wheel support casting on each side. The steering wheel shaft extends down to that rack, and has a pinion gear on the end. This is the solid mechanical link to steering.
For power assist there's an electric motor with a pinion gear also on that rack. There's a position sensor on the steering wheel shaft (above your feet) which feeds the steering wheel's position to the ECM, giving an error between where the wheel is and where the rack is, so the motor moves to correct that error in real-time. That 12v motor is the power assist.
IOW it doesn't matter all that much whether you have it set to Sport mode or not.
Keep in mind, turning the wheels while stopped is by far the worst case.
While the car is rolling it's much easier to turn the wheels (which would presumably be when you'd need to steer in the emergency case.)
While true, it's still difficult. When the power steering went out in the loaner, I had to back up and try again to get out of the driveway and into the alley. It was that hard even when moving.
Hi Jeff,
Your post says that the sc replaced your steering motor. Have I misread or misunderstood what you wrote?
I didn't have any of the normal signs (grinding noise, burning smell, fluid, a dead spot, drifting or wandering) that indicate a broken steering rack. The steering was perfect. I started a firmware update, went in the house, came back out, and the "steering assist reduced" alert appeared. The sc says that Tesla won't replace only the steering motor. The sc says I have to buy a new steering rack ($3,425.95). Your post looks like your sc replaced your steering motor. Did they replace only the motor because it was under warranty? I'm the original owner and out of owner. I didn't' know Tesla sold an extended warranty. The sc
This is the sc's 1st diagnosis: "The diagnosis on your vehicle found the steering rack has an internal fault and requires replacement. "
The is the sc's clarification on the diagnosis: "The vehicle has an internal communication problem with the electronic steering rack assembly. The control module that drives the steering rack and communication with other modules is built into the steering rack assembly. There is currently no communication with this component and the power, ground, and CAN are intact. Therefore, the steering rack assembly has an internal malfunction and requires replacement." After researching this, it looks like the steering motor failure is very common. Other companies, like BMW where all of my mobile techs say they worked before coming to Tesla, replace the steering motor rather than the entire steering rack.
When I asked about the steering motor the sc replied, "The steering rack motor is not serviceable separately as the motor, rack and pinion are one assembly. Because we replace the complete assembly the only diagnosis performed is to determine if the assembly is working within factory specifications. Vehicle logs are always pulled and used as an aid in diagnosing the concern. We do not provide these to customers. If you purchase the parts we will definitely provide you with the faulting steering rack. The purchased new part has a one-year warranty for parts and labor."
The sc won't provide logs, and won't provide a schematic or diagram that explains the part(s) that are broken. The sc, "As for your request for vehicle parts schematics, vehicle log data and company repair statistics, it is against Tesla company policy to provide this information as it is confidential. If you need any further explanation you are more than welcome to speak with either my Manager, ***** ******* or **** *****."
Add'l notes: I drove from Florida to the farthest pacific west corner of the U.S. just a few miles outside of Canada. As soon as the weather got cold, the charging port stopped working. Mobile said there was a fault and replaced the port. An alert to replace the 12-volt battery, that had been replaced before I left for the trip, popped up. Mobile said it was a fault and replaced the 12-volt. Then the left front (LF) and right front (RF) doors wouldn't open with the key fob or my phone. Mobile said there was a fault and replaced the LF and RF door regulators and the LF and RF door handles. The next month, I went to a sc on the drive back to Florida, when 3 windows malfunctioned on the same day and the RF door opened when I put the S in park, used the key fob, or pressed the lock or unlock icon on the touchscreen. I spent $1,995.21 at the sc. The next day the RF and RR door and window continued to malfunction and continued to malfunction on the entire trip back to Florida. Then, the "steering assist reduced" alert popped up.
What are your thoughts and ideas?
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