Introducing the Defender, A drill powered tanked UGV.

Supplies

(x2) 2040x220mm Aluminum Extrusion
(x8) 2040x550mm Aluminum Extrusion
(x2) 2040x700mm Aluminum Extrusion
(x2) 2020x800mm Aluminum Extrusion (Will have to get cut down to 730mm)
(x4) 2020x600mm Extrusion
(x2) 2020x200mm Extrusion
5x5mm Aluminum Square Rod
7mm (side-side) Aluminum Hex Rod
16x5mm 688-2RS 688 RS Rubber Sealed Ball Bearing
14-Inch Heavy Duty Aluminum Alloy Turntable Bearing-250lbs Capacity

(x2) Electric Goddess Electric Drill 20V
(x2-4) 20V 12AH Dewalt Style Battery
(x2-4) Dewalt Battery Adapter
(x2) RioRand Brushless Motor Driver

Printer Filament (I use Rapid PLA+)

UGV STLs

(A bunch of) M3x8 bolts
(A bunch of) M3 Nuts for 2020 extrusion
(A bunch of) 1/4-20 Nuts/Bolts/Lock Nuts/Washers
(x1) 1/4-20 Threaded Rod (5-10ft length)
(A few bottles) 2 Part Epoxy Glue (I got mine from the dollar store)

Step 1: General Assembly Pictures

Just a heads-up: This tutorial may be hard to follow.

I didn't take a lot of pictures when building this (mainly because I was winging everything as I went)

I've been working on this off/on and this is still a work in progress, although mechanically it is 99% complete (Turret mechanism is the only thing missing).

All STLs are released and can be found here.

Step 2: Main Frame

Bolt 2040 extrusions to the assembled inner frame and use 2020x200mm extrusion to space out the 2 inner frames. Secure everything using M3x8 screws and M3 T-Nuts.

On the inner frame, you'll notice a small thru hole sized for 1/4-20" threaded rod. Measure off, mark and drill the 2040 extrusion, so a 1/4-20 threaded rod can be slid through to sandwich the extrusion to the frame (You may use the "Temp-Drill Aligner Template" from the Temporary Parts folder in Printables to help mark/drill your holes).

Refer to the images above.

Note: my rod offset measurements will differ from yours as I was using an older version of the frame without the "built-in" thru hole) Use some 1/4-20 washers and locknuts to secure the threaded rod and cut any excess rod off.

Add 688Rs bearings to the Frame and sandwich them with a "Tank Frame Bearing Plate" on each side and secure with 6-32 nuts/bolts (cut to length)

Step 3: Tank Tracks

The tank tracks were derived from here with assembly instructions being referred from the original model. These tracks are essentially the same, but I used 1/4-20 threaded rod for all sprockets and 6880RS Bearings (x2) 1" EMT pipes and I modified the Drive Sprocket to make it 'Hot-Swappable'

Step 4: Bottom Frame Cover Plates

Once you have the Main frame assembled and secured, you can add the cover plates and secure them with small wood screws (I used 6-32x3/4") I epoxy glued the seal to the cover plate and siliconed the cover plates to the frame to keep it water-resistant.

Step 5: Drive Drill + Shaft

Carefully disassemble the drill and extend the motor wires with properly sized cable (I used 16/3C Cabtire-SOOW), and use coloured electrical tape to phase them properly.

Once the wire is soldered, heat-shrank and phased, Re-assemble the drill and feed the wire through "Drill Battery-2040 Extrusion Bracket (V.8)" (Found under the 'Main Frame' folder in printables) and mount the drill to a small 2040 extrusion piece along the long side of "2040 Double Brace (V.3)"

To make the Drive shaft, slide a 7mm hex rod through the "Shaft block". Test fit the shaft through the bearing and into the drill. Mark how much rod you need to protrude from the "Drive Sprocket " to the drill then smack a 5mm square rod in there to wedge the hex rod in place. Clamp the "Shaft Block" down with 8-32 nuts/bolts and cut flush.

Refer to images above.

Step 6: Fender

Use, 2040x550mm extrusion to create 3 horizontal braces that will be used to slide the assembled fender onto and also add structural support. Measured and centre the 2 outer braces, make them flush/square with the ends of the 2040x700mm extrusion and use 1/4-20 bolts to secure the 550mm to the 700mm extrusion.

Ensure they are squared and do a test fit of the Fender to ensure it slides on relatively easy because if those braces are off by a little bit you're going to have a very hard time installing the Fender (I had to smack my fender in place with a rubber mallet, because my extrusion wasn't perfectly square)

I left the middle 550mm extrusion unbolted (floating) to make it easier for me when installing the fender.

Assembling the Fender is pretty simple. I epoxy glued the two sides together and used some nuts/bolts (I think I used 6-32/8-32 screws) to keep the 2 sides pressed together. For the underside of the Fender I printed the "Fender Bottom Plate 2mm" and used some acrylic sheets I had (cut them to size-The same size as the Fender Bottom Plate) to fill the square gaps on the underside and I just epoxy glued them in place.

For the Headlamp, I took some acrylic sheets I had, cut them to size and glued them to the Headlamp. I kept the front Headlamps clear, and I sanded the back ones to get a frosted effect.

I used a bit of hot glue to secure the 12V spot/flood combo lights in place. (You may have to modify the lights to make them fit in the Fender and extend the wires)

Refer to the images above.

Step 7: Attachment Plate

Centre between the (x2)700mm extrusion (inside-inside) & insert "Attachment Plate Support Bracket" onto the outer 2040 horizontal brace, and secure with M3x8 screws.

Slide and press fit "Attachment Plate V.5.1" onto "Attachment Plate Support Bracket" and drill out the 2 thru holes for the 1/4-20 eye-bolts so they can pass through the 2040 horizontal brace.

"Attachment Plate Top" secures to "Attachment Plate V.5.1" via (x2) 1/4-20x1" bolts and is supported by the "Attachment Plate Support Bracket".

Step 8: Hull

Refer to the images above to frame the Hull. The Hull frame sits right on top of the Fenders and the Hull components bolt directly onto the frame using M3 screws.

If you want to omit the turret riser, Just bolt the bearing directly to the extrusion (as shown in the 2 images above)

If you want to use the riser (Recommended), Then bolt the riser to the extrusion (using M3 screws) and the bearing to the riser (using 1/4-20 bolts)

For the turret, the "Turret Gear-Outer" can be drilled out and bolted to the inner ring of the bearing. "Turret Gear-Inner" will be driven by a motor that will be housed in a bracket that is mounted to the (x3)side holes on the "Turret Riser" (Takes 1/4-20 bolts/nuts).

The Hull Frame will be secured to the body of the tank by some hinges mounted on the "Attachment Plate Top" part. This way you can lift it open to service everything. To prevent anyone from lifting the 'hatch' there is a "Key Lock Mount" located under 'Other-Add-Ons' folder in Printables which bolts to the 2020 extrusion and uses a drawer lock to prevent the 'hatch' from lifting.

"Side Hull" takes 1/4-20 nuts and the "Side Hull Braces" bolts to them. "Side Hull Vents" are fiction fitted in place and secured with glue if need be.

To secure Hull pieces to extrusion, there are holes in the parts for M3x300mm screws to be inserted in.

You may notice a small circular notch on some parts, for example on "Rear Hull Back Plate" there is a notch located centred on top. This is for the 12-24V strobe lights. Just drill that notch out and feed the wire for the light through there and secure the light. On other parts like the "Rear/Top Plate" the notches are located on the inside of the part.

Step 9: Electronics

To drive the drills I used (x2) RioRand Brushless Motor Driver, an Arduino, and A LORA module.

To test your motors, you can wire them to the Motor Driver and use the onboard potentiometer to get them spinning.

I haven't found time yet to actually wire up the UGV and get it completely running, but when I do, this section will be updated (Although it may be a while)

Introduction: Tanked UGV