Small 1/4 inch socket set into a nicer walnut tray

 I was recently thinking about how I could make a selection of 1/4 inch drive bits easier to use. It seems I am not alone in the crowd of people who leave the bits in the case they came in. Some folks do that for many decades. Apart from being trapped into what "was in the set" this also creates an issue when you have some 1/4 inch parts in a case that includes many more 3/8 inch drive bits. I originally marked the smaller drive parts and though about leaving them in the blow molded case as is the common case.

The CNC fiend in me eventually got the better of me and the below is the result. I cut a prototype in pine first, knowing that the chances of getting it all as I wanted on the first try was not impossible, but not probable either. Version 1 is shown below.

 

 The advantage is that now I have the design in Fusion 360 I can cut this design in about an hour. So if I want to add a bunch of deep sockets to the set I can do that for the time cost mostly of gluing up a panel, fixturing it and a little sand a shellac. Not a trivial en devour but the result I think justifies the means.

Below is the board still fixtured in the cnc machine. I think I will make a jig with some sliding toggle clamps so I can fix panels to the jig and then bolt the jig into the cnc instead of directly using hold down clamps.

I have planned to use a bandsaw to but a profile around the tools and may end up with some handle(s) on the tray. That part is something I have to think more about. The thinking about how I want the tools to be stored and accessed is an interesting side project.

 

 

Terry2020 finally making the indoor beast more stable

Over time the old Terry robot had evolved from a basic "T" shape to have pan and tilt and a robot arm on board. The rear caster(s) were the weakest part of the robot enabling the whole thing to rock around more than it should. I now have Terry 2020 on the cards.

Part of this is an upgrade to a Kinect2 for navigation. The power requirements of that (12v/3a or so) have lead me to putting a better dc-dc bus on board and some relays to be able to pragmatically shut down and bring up features are needed and conserve power otherwise. The new base footprint is 300x400mm though the drive wheels stick out the side.

The wheels out the sides is partially due to the planetary gear motors (on the under side) being quite long. If it is an issue I can recut the lowest layer alloy and move them inward but I an not really needing to have the absolute minimal turning circle. If that were the case I would move the drive wheels to the middle of the chassis so it could turn on it's center.

There will be 4 layers at the moment and a mezzanine below the arm. So there will be expansion room included in the build :)

The rebuild will allow Terry to move at top speed when self driving. Terry will never move at the speed of an outdoor robot but can move closer to it's potential when it rolls again.

Bidirectional rc joystick

With a bit of tinkering one can use the https://github.com/bmellink/IBusBM library to send information back to the remote controller. The info is tagged as either temperature, rpm, or voltage and units set based on that. There is a limit of 9 user feedbacks so I have 3 of each exposed.

To do this I used one of the Mega 2650 boards that is in a small form factor configuration. This gave me 5 volts to run the actual rc receiver from and more than one UART to talk to the usb, input and output parts of the buses. I think you only need 2 UARTs but as I had a bunch I just used separate ones.

The 2560 also gives a lavish amount of ram so using ROS topics doesn't really matter. I have 9 subscribers and 1 publisher on the 2560. The 9 subscribers allows sending temp, voltage, rpm info back to the remote and flexibility in what is sent so that can be adjusted on the robot itself.

I used a servo extension cable to carry the base 5v, ground, and rx signals from the ibus out on the rc receiver unit. Handy as the servo plug ends can be taped together for the more bumpy environment that the hound likes to tackle. I wound up putting the diode floating between two extension wires on the (to tx) side of the bus.

The 1 publisher just sends an array with the raw RC values in it. With minimal delays I can get a reasonably steady 120hz publication of rc values. So now the houndbot can tell me when it is getting hungry for more fresh electrons from a great distance!

I had had some problems with the nano and the rc unit and locking up. I think perhaps this was due to crystals as the uno worked ok. The 2560 board has been bench tested for 30 minutes which was enough time to expose the issues on the nano.