# EducateNXT Navigation Accuracy 4 Poles Challenge Programming the EduBot before trialing on the course.

## Presentation on theme: "EducateNXT Navigation Accuracy 4 Poles Challenge Programming the EduBot before trialing on the course."— Presentation transcript:

EducateNXT Navigation Accuracy 4 Poles Challenge Programming the EduBot before trialing on the course

EducateNXT How far am I going? Work out how far one “rotation” takes the robot. Place a small mark on the bottom of the wheel. Go forward one rotation. Measure this distance

EducateNXT Checking using Circumference One rotation is equal to the circumference of the wheel. To measure the circumference, find the radius. Circumference = 2 x π x radius Substitute into the formula: C = 2 x 3.14 x radius C = distance of one rotation

EducateNXT Start Using Distance of a Rotation How many rotations does it take to get to the corner? You may need to use decimals (eg. 3.5 rotations).

EducateNXT Now to get around the corner…

EducateNXT Another Calculation Assuming a pivot turn – one motor only – for right wheel Right wheel forward only

EducateNXT Another Calculation How many rotations to get to Point A? A A quarter turn Right wheel forward only

EducateNXT Calculate Quarter-turn Distance Circumference ( C = 2πr ) divided by 4 Program in a left turn for your robot. How many rotations is this for the right motor?

EducateNXT Good luck with the dotted (outside) line on the 4 Poles Course. Try and program the EduBot for the whole dotted line course before trialing. How far around the course did the EduBot go?

EducateNXT Start At this point, a wide turn needs to be taken – and the programming gets interesting! Now for the Dashed Course…

EducateNXT In order to take the wide arch, the two wheels have to travel at a different velocity. The steering slider in a Move Block is limited to 10 radius of curve turn. A NEW PROGRAMMING TRICK IS REQUIRED for more accurate curve turning

EducateNXT Before the programming tricks… Which set of wheels will create a turning circle with the biggest radius? The arrows’ lengths represent power. A B Answer A – the closer the power of the two motors, the wider the turning arc

EducateNXT Programming a Curved Turn Two ways Split task Wait for time

EducateNXT Split Task Allows two tasks to operate at the same time. In this case, two Move blocks representing two separate motors. Two forms of Branching Click and drag from the starting point. Midway in the program – click and drag while the Shift key is pressed.

EducateNXT Split Task (continued) Things to note: Motor B and C have different powers. 2 different motors – B and C – both going forward Duration is time (not rotations) – can you suggest why? Try both and see.

EducateNXT Wait for time Two separate Move Blocks (with different motors selected) Have different powers Second Curve Turn Technique and are set to duration unlimited

EducateNXT Wait for Time (continued) A “Wait for Time” block is added, and time for the curve turn selected. You can begin accurate curve turning. Choose your method.

EducateNXT Good luck with the dashed (inside) line on the 4 Poles Course!

EducateNXT