Midterm: Introduction to Robotics 16-311

Fall 2005

1hr  15 mins, use one 8.5 x 11 cheat sheet

 

Name:

 

Team:


 

Problem #1 [25 pts]

(a)  Draw the generalized Voronoi diagram for the configuration space for the square shaped robot in the orientation shown. [20 pts]


(b)  Draw the shortest path with respect to the L2 metric between the start and goal locations shown. [5 pts]

 

 

 

 Extra

 

 

Problem #2 [15 pts]

 

The following describes two convolution scenarios. 

 

 

 

(a)  Is the result the same or different? [5 pts]

 

(b)  Why? [5 pts]

 

(c)  What algebraic operation does convolving with the mask [-1 2 -1] do? [5 pts]

 

 

 

 

Problem #3 [9 pts]

 

(a)  How many DOF does a circular robot which can translate and rotate on some point other than its center have? [3 pts]

 

(b)  How many DOF does a robot with a fixed base and 3 revolute joints have? [3 pts]

 

 

(c)  What is the dimension of the configuration space for a robot which can only translate and has a boom on it that can rotate?  [3 pts]

 

 


Problem #4 [30 pts]

 

A 1 DOF prismatic joint is a linear DOF, which as its name suggests, provides motion along a line.  Think of it as a telescoping arm.  The robot below has a revolute joint with angle θ at the base, which rotates a prismatic joint with length s whose range of motion is 0 to 100 cm.  The base joint has no limits.  The robot is shown in its initial position.

 

There are 3 obstacles: two point obstacles at (0,50) and (0,-50), and a curved quarter circular wall with radius 75 cm.

 

Pick a metric and draw the shortest path with respect to that metric.  Draw the end position in the workspace along with 2 intermediate points on the shortest path.

 

Workspace:

 

Configuration Space

 

Problem #5 [21 pts]

 

Draw a line to match the resulting signal with the corresponding mask that was used to convolve the original signal.

 

Original signal:

 

 

 

 

 

  • [1/9 1/9 1/9 1/9 1/9 1/9 1/9 1/9 1/9]

 

 

 

 

 

  • [-1 0 1]

 

 

 

 

 

  • [-1 -1 -1 -1 0 1 1 1 1]