Reviewing and comparing fit artifacts
As you carry out the fit, Velogic Studio records various "artifacts" for each capture. These include:
- Raw videos from the depth camera(s) and/or any webcams you have at different positions around the rider.
- Stroke analysis videos from the depth camera(s), giving a higher virtual-frame-rate and the ability to scrub to particular crank angles
- Metrics calculated from the sensor data, e.g. body angles and movement from the Kinect camera, or ANT+ data from sensors on the rider or bike.
Velogic Studio makes it quick & easy to review and compare these artifacts, so that you can clarify the effect of changes in position - both for yourself, and to show your client what you're seeing & why you're making changes.
Hovering over thumbnails in the Fit Log
The quickest way to review a previous capture is simply to move your mouse over the thumbnail images in the Fit Log at the bottom of Step 2:
When you move the mouse over a thumbnail image for a particular capture, Velogic Studio will auto-play see the videos saved as part of that capture. The Motion Metriqs from that capture will be displayed on the right-hand side, with an asterisk (*) after them to make it clear that these are historical (and not live) numbers.
Because this is triggered by just a mouse move, if you move the mouse away, Velogic Studio will return to live mode.
Locking a capture for review
If you want to interact with the artifacts from a particular capture, just move the mouse over that capture's thumbnail (as above) and then click the "LOCK" button.
The appearance of that capture's thumbnail will change to show that it's now locked:
...and you can then move the mouse off to interact, e.g. to scrub the videos or change into Stroke Analysis mode, or to click on a metric (see below)
Stroke analysis mode
When you lock a capture for review, you'll see the raw video from that capture playing, with a scrubber bar at the top for video control:
You can pause, frame-forward, frame-backward, or just grab the dot to scrub back & forward.
If you click on the Stoke button at the top, the raw video will be replaced by Stroke Analysis video:
Stroke Analysis is a new way to review a capture. There is still a scrubber bar at the top (just like for raw video), but there are some big differences. The horizontal axis of the Stroke Analysis scrubber does not represent time; instead, it represents crank angle. You can see labels for 0° (top of pedal stroke), 90° (~middle of power phase), 180° (bottom of stroke), 270° (~middle of recovery phase) and 360° (back to the top of the pedal stroke).
The small dots which appear along the horizontal axis each represent an individual frame, captured at that crank angle. Velogic Studio has automatically analysed all frames from the capture and re-ordered them to create a virtual-high-frame-rate video.
Note that because the frames have been reordered, if the rider was moving their head during the capture, their head will appear to "flicker" in the Stroke Analysis mode. You might want to ask your rider to fixate on a point and try to keep their head still during the capture to minimise this effect.
When you grab the scrubber and drag left/right, other videos from that same capture (e.g. if it was a bilateral capture) will move to the same crank angle.
Drawing tools and grid
Sometimes you want to draw on-screen to explain something to your client. If you click on the "DRAW" button at the top of the video, you'll see a drawing toolbar appear overlaid on the video:
You can click on the border of the drawing toolbar to move it around within the video area. The tools on the toolbar are probably already familiar to you if you've used other drawing systems in the past, but here's a summary from left to right:
- The "selection" icon lets you draw a rectangle around drawings you've already made, so that you can move or delete them by clicking the Delete key on the keyboard
- The "angle" tool lets you draw an angle with 3 mouse clicks, and will show the degrees inside that angle (or the external angle if you hold the CTRL key).
Note that the angle measured with these tools is a simple 2D measurement; if you were to try to use this tool to measure an angle reported as a MotionMetriq (e.g. knee angle), they are likely to be different - because MotionMetriq's are measured (more accurately) in 3D, using information from the depth camera. - The "line" tool lets you draw a simple 1-segment line
- The "multiline" tool lets you draw a line made of multiple segments. You can double-click or press Enter to finish drawing.
- The "pencil" tool lets you draw completely freehand
- The "text" tool lets you draw textual annotation
- The "save" icon will save a snapshot of the drawing (and the current frame from the video) into the fit folder. It will ask for a name for the snapshot, and will save the snapshot into the fit folder. If you have the "Include annotated images" option turned on when you later generate the report, the snapshot will automatically be included in the report, along with the name you gave it.
- The "delete" icon will delete all drawing items.
- The "close" icon on the right will hide the drawing toolbar. The drawing items will remain on the screen; to remove them, you need you click the "delete" icon on the toolbar.
Clicking on the "GRID" button will overlay a "laser grid", so you can watch the movement against known-vertical and known-horizontal lines (in 2D):
Focusing on one particular metric
You can click on any metric in the MotionMetriqs area:
... it will be highlighted with a "lock" symbol, and a number of things will happen:
- the fit log thumbnails (along the bottom of the screen) will have the value for that metric overlaid, so you can quickly see how it has changed between captures:
- the visuals will automatically skip to the frame which best illustrates that metric (if appropriate)
- a visualization will be drawn on the frame, to illustrate the metric to you and your customer:
There are many different visualizations available, here are some examples:
See also:
- TODO link to Ankle Flexion visualization
- TODO cadence visualization (crank acceleration)
To stop focusing on that metric, just click it again in the MotionMetriqs panel to deselect it.
Comparing 2 different captures
If you already have one capture locked for review (see above), when you mouse-over a different capture you'll see a "Compare" button at the top:
If you click that "Compare" button, the layout of the visuals area will change to put the equivalent visuals from those 2 captures side-by-side, and you can scroll down to interact with each pair:
... and because Stroke Analysis mode is based on crank angle, you can drag the scrubber bar at the top to move both sides with the crank angles synchronized.
In Stroke Analysis mode, there are also additional comparison modes available:
- Side-by-side (the default)
- Overlaid (image):
- Crossfade (video):
- Morph:
The Crossfade and Morph visualizations both generate videos on-the-fly, for the crank angle you have selected. You can click "Save" to save the video as an .mp4 in the fit folder.
Reviewing with the Fit Log Grid
When you really want to drill into the changes between captured positions, you can pull up the Fit Log Grid by clicking on the button to the left of the fit log thumbnails, at the bottom of Step 2:
This will pull up the Fit Log Grid, so that the thumbnails (which were at the bottom of the screen) are now at the top of the screen, with all the data for each position shown underneath in a grid format:
Numeric data (such as metrics) are shown with an indicator showing the change from the initial position.
Related Articles
The bike fit process
Step 1: Configuration and rider details After starting Velogic Studio (and optionally signing in, if you haven’t signed in recently), you'll see Step 1: Step 1 is for you to get all setup prior to the fit session commencing. The client name, email ...Setting up the fit area
Where should the camera be positioned? The camera should be positioned 180cm-220cm from the bike (roughly 6-7 feet) with the lens ideally at a height of 95cm. Relative to the bike the camera should be pointing at the approximate midpoint between bars ...Velogic Studio v4: What's new, and how to transition from v3
In January 2023, we announced that Paraic McGlynn at Cyclologic had taken an equity stake in Velogic and was coming onboard as CEO. Since then, we've been hard at work building a new version of Velogic Studio which will "blow the doors off" (Paraic's ...Knee track
As a fitter, it's useful to know what your rider's knee is doing during the pedal stroke. For example, is the knee moving directly up & down, or is it flaring out (away from the frame) at the top of the stroke, possibly indicating hip impingement? Is ...Taking bike measurements
On the capture screen you will see a button for “MEASURE BIKE”: Clicking “MEASURE BIKE” will open the bike measurement popup window: Bike measurement window Follow the instructions on screen to use the wand to acquire the indicated points. Once you ...