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I love the DIWhy vibes from the last few pages 😍 I have been working a lot on the App and the Firmware for the mast month or so. I have made a lot of progress into packaging it into end to end usable, both on desktop and mobile. Major changes Live data! Now you can stream the sensor readings from a connected DAQ in more or less real time (20-30ms delay). You can set the time on the DAQ and you can edit and replace the configuration, without dealing with memory cards and text files! You can also change...

From what Enrico at byb told me is averages are mostly LSC and 95th/Max HSC but depending on what numbers you see it can pull your averages up. I could be wrong but this is how I interpreted what he said. Also agree with ben c on 95th being less of an outlier.

So I sacrificed a string pot on the altar of science. TL;DR: So far, the results are encouraging. I used a lathe to drive the pot via an offset crankpin, allowing me to calculate the theoretical string trajectory exactly, and the maximum velocities and accelerations at different lathe speeds. The downside of this arrangement is secondary vibration: because the string oscillates vertically, its inertia introduces an error that gets larger as the speed of rotation grows. The good news is that, because it isn’t something the pot will experience in real use and occurs at mid-stroke, I think it can...

Interesting post on IG from @Downamics . It’s a great visual diagram of how each part on the bike set up affects the other. It can also remind us how in the weeds we can get by making a change. “This diagram is an overview of the scope for using DAQ as a holistic and specific analysis tool. It is not a comprehensive guide to the vehicle system or DAQ methodology.“ You can view and use the diagram here: Downamics Framework

Yeah that looks like an off-the-shelf unit (with generic libraries available on github) and Trailmetry is mostly just the app. Weird how it needs to be on a moving part of the suspension, but its on the fork crown up front but the shock body on the rear? Definitely weird.... The Stendec systems used acelerometers for suspension measurement and Downamics has been trying it too. In theory they are a good way to measure damping and actual wheel movement (eg it is possible/common that your wheels are moving up from bump but due to things like friction there is no...

The only way I see to have any meaningfull data from accelerometers to get suspension movement is if you have two accelerometers at each end of the suspension unit (fork crown and lowers or both shock ends) and compare the two. The difference between the two will be what actually moves the moveable part of the shock, from that you could get speeds and then movements. But you're not doing that with 25 USD BT accelerometers. You'd need a serious DAQ with synced channels to do that kind of measurements. As said, that website is full of red flags and...

Sounds like what's needed is a roll-your-own string pot that can be built for about $10... coming soon to an open-source data acquisition project near you. Maybe. This guy runs on the bench and can either emulate an analog pot or be read over I2C. It's built around an as5600 encoder: that plus a couple of bearings, a spring from a key lanyard, a 3d printed spool and a short piece of chrome shaft pulled out of an old scanner make up the driveline. It's multi-turn which keeps it compact (and the inertia low), but at the cost of having...

This is sweet! I'd love to make something similar, would it be possible to pester you about what you used in this setup? A few questions for folks: have people had much luck with string pots? I was thinking for things with shock tunnels (e.g forbidden) using string pots might be a better way to go. Really starting to look at creating a DYI solution to play around with.

I have been seeing the request for leverage curves for offset-mounted linear sensors come up quite a bit more in the last 12 months. If you don't want to calculate this manually I finally got around to actually surfacing this functionality in the UI. The basic process is: - measure your sensor eye to eye length at full extension (or what you want full extension to be, recommended to have a little buffer) - enter the stroke (only required for the visualization) - drag or enter the position points. For convenience the length is fixed and you can just move...

I think the balance you have is great. The averages and 95th looks great. Personally I only give my max speed a glance but I hardly tune for it. The reason being is that if everything else looks good, you are tuning your whole run for one max speed that could be on a drop or big hit. So in reality you’d be stiffening your bike the entire run just for 1 split second. but to answer your question, my max speeds hit 5000-7000 depending on the track. But really the best is to try all the combinations you can...

Work continues on the analysis pipeline for my data logging project. While I have ambitions beyond these kind of basic descriptive statistics, it seemed worthwhile to replicate some of the charts and metrics that seem to be widely used in analysis of suspension data. These, like all my data analysis tools, are built in Jupyter Lab. I have separate notebooks for pre-processing the raw logger data (detecting inactive periods, calculating velocity and acceleration, calculating normalised displacement, low-pass filtering and event detection, assigning semantic roles to data series and stashing it all in a library) and for other general-purpose visualisations that...

Also, I have an Instagram account for the project: Instagram.com/bodaqs.

Luis, We're all patiently waiting for the next case study on this. I am curious your thoughts on average sag.

Some photos from BYB of clean mounting setups!