UnoBot lego® build
You will need 2 Electric Technic Mini-Motors (part No. 43362),
together with 24 tooth crown gears. See
this presentation for a good description of the different gears in Lego® Mindstorms RIS 2.0.
Attach RCX-NXT converter cables and clamp into place with two 2x4 plates.
The motors are held in on each side by two rail assemblies. Each assembly requires one 2x10 plate, two 2x2 plates, two 1x2 plates, and two 1x2 plates with 'door' rail.
For the next stage you also need two Technic 1x16 Bricks with 15 Pin Holes.
Assemble the robot chassis comprising the two motors and the rail assemblies mounted on the Technic bricks.
To assemble the body you will need four Technic Pins with Friction Ridges and four 1x7 Technic Beams. Insert the pins at each corner of the chassis facing outwards.
Attach the four beams to the chassis.
The body frame is a simple box structure. The top of the frame requires four more Technic Pins, and two more Technic 1x16 Bricks with 15 Pin Holes. We also need two 1x2 plates to act as spacers.
Add the 1x2 plates on the underside of each 1x16 brick. A single 2x8 plate is used as a brace to hold the motors in position on the rails. Add the plate to the top of the motors.
Insert the outward facing pins at each end of the 1x16 bricks then attach to form the body frame.
Flip the body frame over so we can see the underside of the motors where we will attach the wheel axles.
The axle shafts require four 2x2 'Specialty' plates with Pin Hole Both Sides, two per side. A pair of 1x8 Technic Bricks with 7 Pin Holes provide additional strength to the motor assembly.
Attach the four axle shaft plates to the outside and the 1x8 Technic bricks to the inside.
For the wheels we need four axles 8 studs long, four 40 Tooth Technic Gears, two White Wheels (49.6x28VR) with Axle Hole and Black Tyres (49.6x28VR), two large yellow wheel centres (split Axle hole) and 17x43 tyres, and lastly eight Technic bushes.
Place a bush on one end of the axle, then add the wheels (with tyres fitted), followed by the gears. The larger white wheels will be the rear wheels with the smaller yellow wheels at the front. Note that the bush fits flush with the large wheel and protrudes on the smaller wheel.
Insert the four axles through the axle shafts and attach a bush to the end to secure in position.
Flip the frame back over, onto it's wheels. The head will be attached to the frame at the end with the smaller wheels. This will be attached by two 1x4 Technic Bricks (Three Pin Holes) and two Technic Pins.
Insert the pins into the 1x4 Technic bricks, facing outwards. To the rear of the frame we will need two 2x10 plates that will form a floor for the battery compartment, and a 1x10 plate to form a spar at the top of the frame.
Attach the 'neck', inserting the pins in the third hole down.
The robot 'head' will contain the three sensors. We focus first on the two touch sensors, connected to the Arduino by a pair of RCX-NXT converter cables.
Four yellow Technic Beam 3x3.8x7 Bent Lift-arms act as 'whiskers' that activate the touch sensors.
Assemble the five parts at the top of the figure to form the base.
Place a 2x6 plate with 3 pin holes on the middle of the 2x10 plate. Attach the two 2x6 plates at each end facing backwards. Add the 2x2-2x2 bracket on top in the middle, again facing to the rear.
Add the 2x2 brick atop the bracket and top-off with a 2x2 plate.
Clip the connector to each sensor with the switch facing forwards and the cables running out to each side.
Attach a Technic Connector with Perpendicular Axle Joiner to each end of the 8 stud long Technic Axle. This will become the front bumper.
To form the top of the 'head' place two 2x6 plates with 3 pins holes next to each other - end to end. Clip them together by adding another 2x6 plate with 3 pin holes across the middle.
To create each 'whisker' take one 3 stud long Technic Axle and insert through the short end of the yellow Technic Beam 3x3.8x7 Bent Lift-arm. Then press a Technic cam onto the same axle. The axle should pass through the wider end of the cam with the short end facing parallel to the long arm of the 'whisker'. Leave the same length of axle protruding from each side of the assembly.
Construct two vertical bumpers by sliding a pair of bushes to the middle of each 10 stud long Technic axle.
Place the bottom end of the 'whisker' axles into the pin holes in either side of the base. Attach the top to clip the axles in position.
Slot the vertical bars (with the two bushes) loosely through the long slot in the 'whiskers' with the cams, then fix into place by sliding on the bumper.
Insert the 6 stud long axles into the end of the long arm of the remaining 'whiskers'.
Slide each one over the vertical bumper, in alignment with the lower 'whisker', and adjoin using the axles at the long end.
Attach the lego® light sensor (facing down) to the 2x2 bracket (protruding downwards by one stud).
The light sensor has a fixed cable so we must attach the RCX-NXT converter cable to the RCX connector.
Attach the head by engaging it first at the bottom, then swinging down the hinged 1x4 bricks to clamp it into position. Attach the light sensor RCX connector / RCX/NXT cable connector combination to the base of the robot in the middle, near the front.
This image shows both the Arduino Uno and the AdaFruit prototyping shield with the motor control circuit and NXT sockets.
The Arduino has two mounting holes that more or less align with the holes in a 2x8 plate with 7 holes. Fix the Arduino to the plate with two small nuts and bolts (be careful not to over-tighten and flex the plate). Connect the two 2x4 bricks together to form a column, and attach to the underside of the plate. This column engages with the body at the point where the light sensor connects to the RCX-NXT converter cable.
Attach the RCX-NXT converter cables to the prototyping shield. I have the front two sockets running to the left and right touch sensors, the next pair running to the left and right motors, and the final socket running to the light sensor.
The battery assembly includes the 11.1V battery, an XT60 to 2.1mm DC plug cable to supply power to the Arduino, and the LiPo battery low-voltage alarm to which a 1x2 plate has been glued. The battery sits in the rear compartment.
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