Integration Project Systems and Control 2013 Group 4

Group Members

Name:	Student id:	Email:
Koen Gruntjens	0760934	k.g.j.gruntjens@student.tue.nl
E. van Broekhoven	0637413	e.c.v.broekhoven@student.tue.nl
W. Geelen	0744855	w.geelen@student.tue.nl
L. Hazeleger	0651762	l.hazeleger@student.tue.nl

Planning

Week:
Feb 18 - Feb 24
- Qualitative analysis of robot
- Derivation of kinematics and dynamics (Leroy, Erik)
- Preparation of first experiment session (Wouter, Koen)
- Investigate different control-design
- Group meeting
Feb 25 - Mar 3
- FRF-measurement and analyse (Wouter,Leroy (Tuesday))
- Coupled/decoupled experiment (Wouter,Koen (Friday))
- Nonlinearity experiment (Wouter,Koen (Friday))
- Static friction experiment (Wouter,Koen (Friday))
- Group meeting (Friday)
Mar 4 - Mar 10
- Continue making FRF-measurements
- Design PID controllers for all joints
- Trajectory planning for all joints
- Group meeting
Mar 11 - Mar 17
- Verify trajectory planning (minimum time trajectory)
- Group meeting
Mar 18 - Mar 24
- Design feedforward controller
- Group meeting

Progress

Week 1

• The first step in this project was to identify the pizza-robot by creating a list of all the (straightforward) (design) requirements of the pizza-robot (to design experiments) such as:
  • The pizza is not allowed to fall during transport, therefore the maximum acceleration (horizontally and vertically) is limited
  • The robot is not allowed to touch the pizza holding brackets, the trajectory design must prevent crashes
  • 3 pizza's must be transported and the pizzas must be transported as fast as possible (approx. 10-15 sec), and thus the fastest trajectory must be found
  • The controller must stabilize the system
  • Controller output is limited, no saturation
  • The accuracy of the pizza-robot end-effector when obtaining a pizza from the brackets should be approx. 5mm
  • Controller output is limited, keep saturation of motors in mind
• A next step was to identify the limitations of the pizza-robot such as
  • Degrees of freedom to specify the workspace of the end-effector
  • The maximum input signals [V] of the motors of the pizza-robot and consequently the maximum velocity/acceleration of each joint
• To identify the pizza-robot in a more specific way:
  • The kinematics of the pizza-robot are derived which are helpfull for the trajectory design and determining the dynamics of the pizza-robot using the DH convention.
  • A simple model (dynamics) of the pizza-robot is determined to possibly use model-based control design (dynamics of the pizza-robot in terms of the generalized coordinates is difficult, consider a simple model for each joint seperately)
  • FRF-measurement experiments are prepared (designing a ref. trajectory, a stabilizing controller)
• Different types of feedback-control are considered which are usable (and possible with the knowledge of the groupmembers)

Week 2

• As already mentioned in week 1, a simple model is proposed to (possibly) use for model-based control design instead of the dynamics of the pizza-robot in terms of its generalized coordinates since this is too complex and not usable as model-based control design. (for every joint a model, with disturbances from other joints)
• FRF-measurements are performed of each joint with a stabilizing controller and a specific reference trajectory, however large friction is encountered which seems to be not constant along the trajectory of each joint. This influence the FRF-measurements at low frequency. (improve FRF-measurements)

Week 3

• It took a bit more time for doing the FRF-measurements. Finally we have all FRF's of the joints and all group members designed a stable controller for two joints.

Vertical displacement	Horizontal displacement
Rotational displacement	Linear displacement