Page 60 - Toucpad robotics C11

Rotating: When you click on a shape, curved arrows appear around it. You can click and drag these arrows to rotate
u
the shape around the X, Y, or Z-axis. This allows you to orient the shape in any direction. For instance, to place a
robot’s motor mount at a specific angle, you would use these rotational tools.
Designing Different Structures
A Robotic Chassis: You could start with a flat rectangular prism as the base
u
of the chassis. Then, you could add four cylindrical shapes for motor mounts at
the corners, rotating them 90 degrees if needed. You could then use the "Hole"
feature (a special tool in Tinkercad that subtracts one shape from another) to
create openings for wheels and other components.

A Simple Gripper: To design a basic two-finger gripper for a robotic arm, you
u
might create two long, thin blocks as the fingers. You would then use the rotation
tools to orient them correctly and the move tool to position them so they are
aligned to grasp an object. By combining these shapes, you create a new, more
complex structure.

u A Sensor Mount: You could design a custom enclosure for a sensor by creating a box shape and then using the
"Hole" feature to create an opening for the sensor to fit in. You would use all six degrees of freedom to precisely
position the opening and any screw holes for mounting.
Tinkercad’s simplicity allows students to grasp these fundamental principles intuitively. By actively moving, scaling, and
rotating shapes, they are directly applying the six degrees of freedom that govern all rigid body motion, a concept that is
directly applicable to a robot’s physical movement.

The Collapsing Robot
After working solidly for 10 hours in a warehouse, a delivery robot suddenly collapsed
mid-shift. The team was bewildered but simply restarted it after a quick “oil-and-battery
break.” They joked about giving it a medal for “Longest Shift (No Pay).”
actual funny
incidents Learning: Machine endurance has limits; regular maintenance keeps them going.

Planar Mechanisms: Motion in Two-Dimensions

A Planar Mechanism is a mechanical system where all the links and Joint 2 Link 2
joints move within a single, two-dimensional plane. This means their
Link 1
motion is confined to a flat surface, with no movement in or out of
that plane. While this might seem like a limitation, it simplifies the
design and control of these systems, making them highly effective for Joint 1 End of arm
a wide range of applications.
The motion of a planar mechanism can be fully described by the
Link 0
positions and orientations of its links on a flat (X-Y) plane. This
simplifies the mathematical analysis, as we only need to deal with
Base
two translational degrees of freedom (moving along the X and Y
Ground
axes) and one rotational degree of freedom (turning around the
Z-axis, which is perpendicular to the plane).

Key Components of a Planar Mechanism
A planar mechanism, like any mechanism, consists of a few basic components:

Links: These are the rigid bodies that make up the mechanism’s structure. They can be of various shapes and sizes.
u
58
Touchpad Robotics - XI