Lab 8: Stunts

Objectives:

The purpose of this lab is to combine everything we've done the previous labs to execute fast stunts.

Materials

Lab Taks

Closed Loop

I chose to Task A in Lab 6, so in this lab I had to execute a flip. More concretely, the task was to drive forward towards a wall and perform a flip when the car was approximately 0.5m away from the wall and drive back in the direction it came from. I used the Kalman Filter to predict future readings of the sensors so that I could compensate for the slow sampling rate of the sensors. To do the flip, the car has drive towards the wall at a speed sufficiently high speed (not necessarily top speed) and when it reaches half a meter a way from the wall, the car is programmed to drive its motors in the opposite direction at Max speed so that the change in momentum causes the mass to flip. There were alot of things that affected this stunt, to name a few:

  • Wheel Traction
  • Quality of Kalman Fileter
  • ToF Sensors
  • Motor Battery
  • Relative PWM values of Motors

Unfortunately, I was not able to perform the stunt in the intended way because my wheel traction were low after I had put tape on it to the Lab9 Mapping Scan in the Lab. Nonetheless, I have included below my version of the flip as well as the Kalman Filter model and pwm input I used to to attempt the closed loop stunt.

Open Loop

For this segment of the, I won't be using information from my sensor to perform a stunt but rather I will program sequence of actions for the motors do which done collectively will execute a stunt of my choice

First Stunt: Side Wheel Traversal

In this stunt, the robot roams around its environment on its side. This stunt is difficult not because of the control sequence but rather, because the robot moves in plane that makes it unstable but nonetheless I was able to reprocduce it. See below for the program sequence I used to perform it.

Second Stunt: Side Drift Drive

In this stunt, I tape the wheels of the robot. The robot drives forward at full spped for one second and then immediately tries to drive backward at full speed again. During the transition from forward to backward, the car achieves side drift. This skid/drift is caused by the low kinetic friction provided by the tape. Displayed below is the control sequence as well as the video.

Third Stunt: Forward + Single Side rotation

In this stunt, the robot car drives forward at a slight angle for one second and the spins at full speed using only two wheels on the same side to face fully forward. I've added two different videos of the same stunt idea below so I can show it from different distances. The motor sequence is also shown below

I.

II.

Blooper: Ouch That Hurt (Stunt 1)

As well all know things don't necessarily go as planned.I mentioned before some of the stunts were hard to execute so on that note check out this fail of side Traversal

Fail 1: Side Traversal
Fail 2: Flip attempt