TouchDRO V3 Almost Ready

For TouchDRO V.3 release status and access to Alpha or Beta testing please refer to the TouchDRO V3 Release Status page.

Over the last several months, I've been concentrating on getting V3 of the TouchDRO application out. Since the start of April, I've been testing it in my garage shop, and at this point, the application is pretty close to being ready for the public "beta" release. There are still a few areas that need a bit of polish, and USB connection support is still not re-implemented; but other than that, it's been pretty solid. A few weeks ago, I started publishing weekly builds to the "closed" testing track in Google Play Store, and several people have been using the application in their shops. If things go as planned, I will start inviting more people over the next week or so.

In this post, let me go over the current status of the development and cover some of the notable new additions. At the end of the post, I will also explain how to get into the "private" testing program (if you're interested).

Development Status

As I mentioned earlier, the TouchDRO V3 is for the most part ready to go, with a few minor exceptions.

First of all, I still need to re-implement the USB connection support. In Android OS, support for USB "Virtual COM Ports" is implemented at a very low lever. Unlike BlueTooth, where all devices share the same Serial Port Profile, with Virtual COM Ports each device generally requires a separate custom driver (although some chips have kernel-level support on some devices). I've been planning to drop USB support in the new version, but since there appear to be people who use TouchDRO with a USB connection, I can't do it at the moment. Consequently, I will have to re-implement USB support before the new version can be released to the Play Store.

Second, there are some aspects of tool library migration that are still a bit flaky. In particular, this applies to TouchDRO setups that use multiple Preference Banks (now called "Configurations"). The issue is that in the current [old] version Saved Tool Library is global. In other words, tools are not stored with each preference bank and are instead machine specific. This was creating some annoyances for people who shared one tablet between two lathes or milling machines, so in V3, I changed the tool library to be configuration-specific. This means that the internal storage structure will be different, depending on whether or not the application was upgraded from V2.5 or installed on a "clean" tablet. Although I tested the "happy path", there are still some edge cases that I need to handle.

FInally, I need to finish a few new lathe-specific functions. So far, the Milling Machine mode has received a lot of updates and enhancement, but the Lathe mode is still pretty basic. I started working on a couple enhancements, but my new lathe doesn't have a DRO yet; so, I haven't had a chance to test them in the shop. These features are disabled in the weekly builds, and I will cover them in a future post once the functionality is finalized and fully tested.

New Additions

Since the last post, I've added some more functionality to the Graphical View display, and finally, implemented Electronic Edge Finder support (AKA Touch Probe).

Electronic Edge Finder

TouchDRO adapter hardware had touch probe/tool setter input support for a few years, but until now, there was no support for it in the application. On a traditional DRO, the function of an electronic edge finder/tool setter is very simple - you select an axis and when the edge finder/tool setter input is activated, the axis readout is set to zero. At first, my plan was to implement something similar in TouchDRO and then add more advanced functionality in the "Plus" version later. After using this simplistic function for a few days, it became obvious that it was borderline useless. Consequently, I ripped it out and added a new "Indicate Workpiece" function that can set X and/and Y axis origins. Notably, the function can be used with a touch probe (if one is present) or in manual mode, with a basic edge finder, wiggler, or other device.

The function is accessible from the function strip (the second-to-last button in the screenshot below).

Pressing the button brings up the "Indicate Workpiece" dialog shown below.

The four buttons on the left will let you select which edge is being indicated at the given time.

If the "Edge Finder" mode is enabled in the application preferences, pressing one of the buttons will activate the "Scanning" mode (the button will show an animation that depicts probe stylus approaching the workpiece edge). Once the probe is triggered, TouchDRO will capture the position and make it available to be applied to the origin. Otherwise, long-pressing one of the edge selection buttons will capture the current spindle position without waiting for the probe trigger. If the "Edge Finder" mode is not enabled, pressing the button will behave like a long-press.

Once an edge is indicated, it can be used to set the origin to that edge's location (TouchDRO will automatically add or abstracted the edge finder tip radius as needed). Indicating the second edge of the same axis will enable all three options for the origin location. For example, if the X axis has both sides of the workpiece indicated, you will be able to use Left, Right, or Center to set the origin.

As a result, this function can be used to indicate a single edge, a corner, a centerline, or the center of a workpiece. The location can then be used to set either the absolute or the incremental origin. For the sake of convenience, the value entered into the "Stylus Diameter" field will be stored in the persistent state for the current configuration and will be prefilled the next time you open the dialog.

Graphical View Enhancements

There are a few new enhancements in the Graphical View display. They are all somewhat related and are designed to make working cutter radius compensation much more convenient.

First of all, if the tool radius offset is active, the display will show a circle that represents the diameter and the center of the selection in relation to the calculated position. The display is mostly informational, but the circle is also "clickable". Tapping it brings up a tool offset direction widget, so you will be able to quickly change the offset direction. Long-pressing the circle will let you clear the offset.

Second, you will now be able to add "Guides". These are vertical and horizontal lines that can be added at any arbitrary location. In the screenshot below, these are shown as dark-red lines; when activated, the color changes to a lighter shade of red.

TouchDRO Graphical Display

These Guides are stored with each workspace and are somewhat similar to sub-datums in the sense that when activated, they become the new origin for their intersect axis. The Guides can be added by long-pressing anywhere in the blank space or from the sub-datum context menu; they can be activated/deactivated by simply tapping on a guide.

Finally, related to the previous item, there are now two additional automation modes in the Graphical View. In the screenshot above, you might've noticed two buttons in the upper-right corner of the workspace projection display. The button on the left is the Auto Proximity Warning Selection button. In this mode when a guideline is activated, TouchDRO will automatically turn on near-zero proximity warning for the relevant axis. The button on the right is the Auto Tool Radius Compensation Switch. When this mode is active, selecting a guide will switch the tool radius compensation direction, so the DRO will read the position of the cutting edge which is facing that guideline.

Minor Changes

In addition to the additions described above, I've made a number of small tweaks to the application. There are too many to list here. They include numerous cosmetic changes, bug fixes, etc. The two more notable ones are:

Display text size now respects OS-wide font size selection, so you will be able to tweak the font size of most text elements. This includes most icon buttons as well.

The application now uses floating point numbers for internal position storage. This means that it's now possible to use scales that have sub-micron resolution. While it's not a very common use case, I've been asked for this several times by people who wanted to use TouchDRO on some laboratory measurement equipment. Now the maximum theoretical resolution is something ridiculous (like 10 to the power of -45)