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What's with the Position Sensors???

cjust2006

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Generally, what's the deal with just about everything that can move inside the truck not recalling or moving to positions correctly? When I first got the truck (very early on) lots of people's vents never went back to where you left them (fixed with software update), and now the seat and steering wheel need calibrating like every 2 weeks as they start to wander away from their intended positions for entry and exit... Very occasionally, the windows need this too. I've had numerous cars with these features and they didn't have the issues. What's Rivian doing so consistently different that would cause this? What gives?
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Zoidz

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Generally, what's the deal with just about everything that can move inside the truck not recalling or moving to positions correctly? When I first got the truck (very early on) lots of people's vents never went back to where you left them (fixed with software update), and now the seat and steering wheel need calibrating like every 2 weeks as they start to wander away from their intended positions for entry and exit... Very occasionally, the windows need this too. I've had numerous cars with these features and they didn't have the issues. What's Rivian doing so consistently different that would cause this? What gives?
There are two methods to establish positions, not surprisingly - analog and digital. Using the window as an example, the old school method was analog - when the window is full up or full down, the motor current spikes. That spike in current is used to determine the position and shut off the motor.

Digital methods for windows, seats, vents, etc. are done either with a fixed position sensor (sensing only full open/close), and/or with something called an encoder and software to know exactly where the position is at any given time. From the descriptions of the problems and Rivian's calibration procedures, it seems like they are using encoders and software to determine position. The problem is that if for some reason the software loses the calibration data, or the encoder mechanically slips or skips pulses, the calibration data is incorrect. Software updates can fix many of these issues.

Rivian R1T R1S What's with the Position Sensors??? 1706121200466
 
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cjust2006

cjust2006

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There are two methods to establish positions, not surprisingly - analog and digital. Using the window as an example, the old school method was analog - when the window is full up or full down, the motor current spikes. That spike in current is used to determine the position and shut off the motor.

Digital methods for windows, seats, vents, etc. are done either with a fixed position sensor (sensing only full open/close), and/or with something called an encoder and software to know exactly where the position is at any given time. From the descriptions of the problems and Rivian's calibration procedures, it seems like they are using encoders and software to determine position. The problem is that if for some reason the software loses the calibration data, or the encoder mechanically slips or skips pulses, the calibration data is incorrect. Software updates can fix many of these issues.

1706121200466.png
That's an amazing reply. I get why my past cars were fine on the windows, likely being analog, but there wouldn't have been any current spike for things like the memory seats and steering. I'm not sure how Rivian is reinventing that wheel, lol.
 

Zoidz

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That's an amazing reply. I get why my past cars were fine on the windows, likely being analog, but there wouldn't have been any current spike for things like the memory seats and steering. I'm not sure how Rivian is reinventing that wheel, lol.
Rivian is using off the shelf hardware available to all manufacturers. As an example, NXP makes a complete product line chipset for vehicle control. I don't know if Rivian is specifically using NXP, but Rivian and other manufacturers buy a chipset and write the software.
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