Wesley's Tool-Box

To keep a detailed log of the Bolt EV's battery status, I've been using a Bluetooth OBD-II adapter that connects to a smartphone for the past two years. While it worked well, I wanted to have a permanent display showing the data and installing an iPhone to do so seemed to be an overkill. So I searched for dedicated "gauge" units that allowed for customization and narrowed the selection down to ScanGauge 2 and UltraGauge MX. The former allowed for more custom data (25 PIDs vs. 8), while the latter had a bigger screen (8 lines vs. 2). I ended up with the bigger screen.

With the device at hand, I had to find a way to program it to display Bolt EV-specific data using the existing custom PID information, and then install it on a place where it is both easily visible and properly shaded. After a bit of work, I was able to fulfill all of the objectives, as you can see in the photo above. The first page shows the actual vehicle speed, accelerator pedal position, various battery information including State of Charge (both raw and displayed), usable capacity, and temperature, as well as current trip distance and 12V battery voltage. Let's see how this was done.

Initially, UltraGauge detects how many of the 60 standard OBD-II PIDs (Parameter Identifications) and 28 self-calculated data it supports are available on the car. Because Bolt EV does not have an internal combustion engine, most of these are irrelevant and unsurprisingly unsupported. Of the 20 said to be usable as shown here, only 7 of them are standard PIDs and none are related to monitoring the high-voltage propulsion battery.
So I had to devote all of the eight custom PID slots available for this purpose. The problem is that the screen for configuring them (MENU - Gauge/Page Menu - Select Gauge/Page - M Gauge Setup) looks like this:

And it's not easy to make sense of it at first. I needed to translate the information found in an unofficial list of custom PIDs for Bolt EV into this format. After reading the UltraGauge MX programming supplement and researching the CAN Bus protocol, I was able to do just that. For these PIDs...
I programmed UltraGauge like this:
You can see that TData is composed of the header and the PID. The header specifies which ECM the data should be coming from and there are at least eight of them (E0 to E7) on Bolt. The numbers used in the formula are entered in hexadecimal, as with other inputs. After making sure that the programmed PIDs were working as intended, I went ahead with the permanent installation of the device.

SpaceX Crew Dragon launched on May 30, 2020, under the mission name DM-2, became the first privately operated spacecraft to reach the Int'l Space Station with a human crew. It is now docked to the Harmony module at the forward end until around August, which makes it possible to be seen when the station is overhead. I made some attempts to photograph it, and these are the first clear results coming from the space station's transit in front of the Sun.

With a distance of 448.9 km, the station would have an angular diameter of 61.6", which made it easier to notice the docked spacecraft in question. You can clearly see the difference when you compare the new photos to the one I took 5 years ago, when another SpaceX spacecraft, the Cargo Dragon, was berthed to the bottom of the Harmony module (and thus not distinguishable from the overhead view) for the CRS-6 mission.

To take these photos, I drove to Hamyang on my Bolt EV. It was about 100 km away from home, but the weather was excellent and I didn't want to waste a good opportunity. I was glad that everything went right. The photo from 5 years ago is an enlarged composite of multiple frames took by an iPhone through a telescope. But it seems that a single photo taken by Nikon P1000 on its own surpasses that with proper focusing, even though the setup is much simpler and lighter. I guess I'll be bringing around the camera to more places.

Device: Nikon P1000
Settings: 3000mm - ISO 200 - 1/2500s - f/8
Filters: None
Time: 2019-06-22 13:53:20 KST
Location: Hamyang, Korea