The calibration of a 9 degree of freedom (DOF) robotic manipulator using multiple three axis accelerometers and an embedded system will be accomplished in this work. The 9-DOF robotic system used in this study is a 7-DOF robotic arm attached to a 2-DOF power wheelchair. Combined they create a Wheelchair Mounted Robotic Arm (WMRA). The problem that will be solved by this thesis is the calibration of the robotic system during start up. The 7 DOF robotic arm is comprised of rotational joints only. These joints have dual channel encoders to determine the joint position, among other useful data. The problem with dual channel encoders is that when power to the encoders is turned off and the motor is moved, then the robot controller does not have accurate position data when the system is powered again. The proposed calibration method will find the angles of two joints per three axis accelerometer. Four separate accelerometers are mounted on different locations of the 7 DOF robotic arm to determine the arms joint values. To determine the orientation of the base frame, an inertial measurements unit (IMU) is mounted to the origin of the base frame. By using this system of accelerometers and inertial measurement unit, the WMRA can be completely calibrated during system start up. The results collected for this calibration method show joint estimations with an error of +-0.1 radians for each joint. The results also show an accumulation of error for joints that are farther from the base frame.

Wheelchair-bound individuals who have limited or no upper-limb usage have difficulty with picking and placing of objects, opening doors, and other activities of daily living (ADLs), such as turning on a light switch or drinking from a cup. A wheelchair-mounted robot arm (WMRA) would aid individuals with completing ADLs and increase their independence, therefore an improved WMRA has been designed. Building upon previous WMRA research and incorporating research from industrial robot arms, carbon fiber tubing is the main component for the structure of the arm, a novel development for WMRAs. Factors that go into WMRA design include weight, speed, safety, robustness, cost, and the anticipated tasks. Many of these factors, such as weight, speed, and cost, can be improved upon compared to previous WMRAs by using carbon fiber materials. The use of carbon fiber enables the arm to be strong, but also lighter weight than other WMRAs. Testing was conducted on the pultruded carbon fiber tubing to ensure that the structure of the arm could withstand the necessary bending and tensile forces for the arm to hold up to 3.85kg, the standard weight of a gallon of milk, at the end effector. The arm's carbon fiber frame also allows the motor and sensor wiring to run internally, which improves the arm's safety and aesthetics, while protecting it from the arm's external environment. Lightweight high-torque motors, harmonic drives, newly designed carbon fiber frame, and a stand-alone 8-axis motion-control board, allow the arm to weigh less, have a longer overall length, be more robust, and be safer electronically than the previous University of South Florida WMRA, which was shown through prototype testing.

A wheelchair-mounted robotic arm (WMRA) was designed and built to meet the needs of mobility-impaired persons, and to exceed the capabilities of current devices of this type. The mechanical design incorporates DC servo drive, with all actuator hardware at each individual joint, allowing reconfigurable link lengths. It has seven principal degrees of freedom and uses a side mount on a power wheelchair. A simple, scalable control system allows coordinated Cartesian control, and offers expandability for future research, such as coordinated motion with the wheelchair itself. Design payload including gripper is 6 kg, and the total arm mass with controller is 14 kg. These and other design attributes were confirmed through testing on the completed prototype.

A Wheelchair-Mounted Robotic Arm (WMRA) was designed to aid people with limited or no upper-limb usage to accomplish activities of daily living (ADLs). The primary objective of this research was to enhance the performance of the WMRA by improving the communication protocols and functions between the hardware and software used for its control. Previously, the control algorithm of the robotic arm was tested in simulation and in the physical arm. These implementations required a combination of Matlab and C++ language and introduced some software instability under Windows operating system. To improve the performance of the WMRA, the programs for hardware control were separated from the ones intended for simulation. The control algorithm of the arm was rewritten using C++ language to facilitate the communication with the controller boards and to make the system more stable and reliable. As a result, the communication delays were decreased since the interfaces between different programs is no longer needed. Preliminary tests were performed to demonstrate the stability and reliability of the new control algorithm. The overall response of the control implementation was enhanced and the algorithm routines and optimization procedures achieved the same goals with more efficiency. Accuracy and repeatability tests were performed, and data was collected and analyzed.