Orbis

At Orbis, I was one of two full time mechanical engineers. I had to hit the ground running, learn quickly, and take ownership of many projects, which was a fantastic opportunity. I thrived in this fast paced environment, leading design on a planetary gearset retrofit project for an electric-converted McLaren MP4-12C, an integrated gearbox/motor/upright assembly, a hybrid battery mounting solution, and the optimization of an external brake rotor/”bell.”

I learned a lot at Orbis - one of the skills I was able to improve on the most was designing for manufacturing. I was in constant communication with Scott, the machinist and a co-founder of the company - I frequently asked him questions about how to make a part more machinable.

Planetary Gearset Retrofit

Requirements

• Reduce operating NVH
• Extreme timeline
• New gearset must fit within existing assembly and use existing splines
• Cost effective

My contributions

• Solely responsible for retrofit design and management
• Sourced gearset and worked directly
• with our machinist to make parts
• Tested NVH reduction with sound level meter
• Fitted to McLaren MP4-12C chassis

Me in the electrified McLaren MP4-12C chassis w/ retrofitted gearsets.

Before retrofit

After retrofit

Design Process and Results

• New planetary gearset designed with helical gears
• Quotes showed that custom ring gears were too expensive and had long lead times
• Needed to pivot - a gearset from a junkyard automatic transmission was harvested and retrofitted to the assembly
• Testing with sound level meter proved significant NVH reduction
• Engineer sent from a major automaker from Wolfsburg approved the proof of concept’s NVH, resulting in a contract with the automaker

NVH testing with retrofitted gearset

Retrofit CAD exploded view

Gearbox, Motor, Brake, and Upright Assembly

Requirements

• Redesign previous assembly, keeping successful design elements and addressing failures
• Small form factor/stack height
• Lightweight

My contribtions

• Redesigned gearset stack - bearings, oiling, gearset selection
• Designed and optimized brake bell (red) with FEA
• Designed integrated upright (orange)
• Redesigned frustum that contains gearset (green)
• Work with machinist to make a printed model

Assembly CAD

Assembly CAD section view

Bell FEA

Design Process

Address failures

• Previous bearing solution caused gears to take load from wheels and fail - redesigned to isolate gears from external forces
• New sealing solution designed to stop leaking

Reduce assembly’s stack height and weight

• McLaren MP4-12C upright integrated into motor mount
• Power dense axial flux motor used
• Lightweight brake bell, external rotor/internal caliper setup
• FEA used to optimized brake bell, reducing unsprung and rotating mass

External Brake Rotor/Bell

• Designed and worked closely with machinist to make “bell” to mount external brake rotor
• Mustang GT rotor lightweighted and adapted to function as an external rotor
• Tested at Greening to validate performance vs. original rotor
• Underperformed compared to original rotor, but was significantly lighter

Conclusions

• Promising results, but an equal mass comparison would be more valuable
• Brake rotor cooling optimization needed

Brake test setup at Greening

Brake rotor/bell pre and post test

Promaster Van Hybrid Conversion Battery Mounting

Requirements

• Mount to Promaster box truck with minimal modification
• Less than 4 hour assembly time
• Easily installed and removed by non-specialized workers
• Corrosion resistant

Design

• Bolted to truck with 24 nut-serts in 6 locations - holes are already present, no modification needed
• Complete assembly and installation instructions made
• Corrosive resistant materials used for water resistant electronics enclosure and splash guard
• Sheet metal construction allows for easy prototyping and ramp up of production

Battery mounting shown without mounting locations

Battery mounting shown with mounting locations from below