Integrated System Build & Test
Table of Contents
We spent the fourth phase of MSD II primarily dealing with budgetary issues, alongside development of subsystems whose parts had recently become available. The spline was worked on to attempt to resize the shaft and remove the spline gear. The IGBT bus bar was designed, and the IGBT was tested under low power conditions. The safety circuitry was developed and tested. Circuits were finalized and soldered. Relays were tested.
MSD II Plan
Test Plan Summary
The general approach for our test plans is a subsystem-up
approach. Some of the major systems, such as the load
generator, require the safety and sensing subsystems to
already be in place. Diagnostic testing is done behind
the scenes and is not considered part of the
commissioning testing. The detailed test plans for the
major engineering requirements can be found at the
following link: note that some are "specified" and won't
need to be tested.
Subsystem Assembly and Design
Bench and Coupling Subsystem
Bench Motor Mounting
- Motor Mounting to the Bench Subsystem --- Design Completed
- Extra T-Slot to be used for sliding motor mounting
- Sliding with proper locking on slots will allow for chain tension
Motor Bracket and Drivetrain
In order to properly support the golf cart motor, we not only needed a mounting bracket but another bracket and bearing to center the armature inside the casing (preventing friction):
The direct mounting bracket is shown below. We still need to finalized hole measurements due to the worn state of the casing:
The Golf Cart Motor contains an old spline design to couple the shaft into the motor. Because this design is not currently manufactured, we will need to have our own shaft machined. Discussion with the machine shop confirms this kind of design can be successfully made, and simulation showed aluminum (much easier to machine) will successfully handle the load with a wide safety margin. The shaft will couple to the same sprocket as on the PERM with a standard keyway.
The PERM motor has a similar mounting bracket:
Ordering StatusAll lead time components are ordered.
Risk and Problem Tracking
- Losing an expensive component
- Load generation safety
Budget RequestThanks to a sponsorship by RIT's Student Government for $1000, as well as the donation of the Poly shielding from Curbell Plastics, we now have the funds to successfully finish purchasing the remaining items on our BOM. Many of these critical items have already been purchased, with the rest being taken care of this week. This will allow us to move forward with the new revised project plan.
- Enclosures/Wire Routing ($50)
- Uncertainty with Curbell Poly Shielding Sponsorship -- Mar 30 ($200)
- No Shelves ($200)
- Power Supplies - Lab Only ($50)
- Extra IGBT Cost/Safety
- Temp Sensing (~$20)
- Temp Sensing Amplifier (~$20)
- Forced Air Min/ Liquid Cooled is Best (~$100-200)
- Heat Sink Upgrade (~$100)
- Thermal Paste (free)
- Laminated Bus (?? -- will know tomorrow)
- Additional Caps ($60)
Updates Since Last Review
- The spline is really hard
- dSPACE sensors finalized and soldered
- Safety circuit is tested on both halves of the transistor.
- Test results are coming in