Precision Motion Engineering in Cannabis Manufacturing

As legal cannabis markets expand, the demand for automated manufacturing solutions tailored to the industry’s unique challenges grows. Automation in cannabis manufacturing challenges traditional machine design paradigms because cannabis flower is a sticky, moist, non-uniform biological material, unlike the dry, uniform tobacco leaves that cigarette machines were designed for.

RollPros, led by mechanical engineer, founder and CEO Kyle Loucks, developed a motion system specifically designed to replicate the tactile, nuanced hand motions of rolling joints with precision, consistency and adaptability.

Guided by curiosity, Loucks custom engineered a belt system as the key rolling medium and combined it with flexible electronic controls and IoT connectivity on a modular machine to design a solution for the cannabis industry’s emerging need of bridging craft quality with automated scale.

Coding Curiosity Meets Mechanical Engineering

Loucks’ background spans medical device startups, hardware engineering for major technology companies and virtual reality hardware development. His entry into the cannabis manufacturing space began with his desire to expand beyond hardware engineering into embedded coding and system integration, skills that traditional management had discouraged him from pursuing.

READ MORE: Pecision Engineering for Automating Cannabis Manufacturing

“I always wanted to learn code, and I had never been really given the opportunity because I had just crushed it in hardware engineering...that any manager is like ‘no way, don't waste your time…coding.’”

Loucks told Machine Design that his hands-on experimentation started with Arduino kits at home. He was making some “fun projects” in his garage, he said, and “it was kind of getting to the point where [I needed] a real project.”

Mimicking the Motion of the Human Hand

Loucks said the belt itself is a consumable rolling medium that is replaced every 10,000 to 20,000 joints. Traditional cigarette machines rely on preformed injection-molded components to shape cigarettes, which Loucks says was not suitable for cannabis. Instead, RollPros developed a proprietary belt material that serves as a “second pair of hands” to gently shape the joint.

Technically, the belt is a composite with a stiff woven inner layer that ensures dimensional stability and enough rigidity to apply rolling pressure while having a nonstick surface to prevent adherence of sticky cannabis flower or rolling paper. “Because [the belt] effectively takes the wear-and-tear, the rest of the machine enjoys vastly extended life,” he explained.

This design choice isolates wear to a low-cost part, allowing controlled maintenance schedules and predictable servicing intervals that can result in long-term machine uptime in commercial environments.

The BlackBird uses an industrial-grade, 3,000-meter bobbin of rolling paper sourced from a French manufacturer with centuries of craftsmanship specializing in tobacco paper, Loucks said. This continuous paper feed system contrasts with the common use of pre-formed cones made overseas.

“Pre-made cones were a red flag for me,” Loucks recalled. “It's not sustainable or cheap after you roll a joint and get flower on your fingers…you know loading cones properly is just not going to happen.” The bobbin-powered system allows the machine to maintain consistent tension and paper quality while avoiding supply chain vulnerabilities and wasteful packaging.

Precision dosing and weight feedback were other considerations for Loucks. Precision dosing is especially important to meet legal state limits on cannabis weight per joint and prevent overfill. The RollPro system uses multiple vibratory feeders that deposit material onto a load cell scale under continuous feedback control, he said.

A Modular, Code-Controlled Approach

Despite the prevalence of PLCs in industrial automation, Loucks chose Arduino microcontrollers for firmware control complemented by a custom MOSFET breakout board (BOB) to handle actuator power switching. “All machine firmware runs on Arduino, backed with a custom BOB…with MOSFETs for air cylinders and sensors,” he explained.

His reasoning included rapid prototyping, direct code control and supply chain resilience during pandemic component shortages. “I tried PLCs but scrapped the project when pandemic shipping bottlenecks hit,” he said. “Arduino lets me control all of the code, make hardware changes at will.”

Loucks also had to tackle material variability. Cannabis flower properties—including moisture, stickiness and particle size—vary widely by strain and processing methods, and this can make robust handling difficult. Loucks says his machines incorporate modular feed systems that can be easily swapped. “The feed system is bolted on with just four bolts,” he noted. “If I need to scrap and redesign, that swap is easy.”

A vacuum blade and particle separator remove excess keef and dust that could otherwise gum up mechanics. “We have a vacuum blade that pulls excess keef off and a cyclone separator to reclaim it,” he said. This system improves machine cleanliness and allows recovery of the material, boosting yield and hygiene.

Debugging, Integration Challenges

Loucks faced typical but tough-to-debug integration issues such as sensor false positives from electromagnetic interference (EMI).

“AC wires too close to sensors caused door interlock faults. It took oscilloscope analysis, wiring rerouting and grounding improvements,” he said, highlighting the engineering mindset that was needed: “You [have to] be inquisitive and curious, okay with stuff not working. When something doesn’t work, many throw up their hands. But if you’re curious, you say, ‘Hm, why’s that? Let’s figure this out.’”

RollPros machines prioritize craft cultivators and small-to-medium producers rather than mass production. “My machine runs about 1,000 joints per hour; one person can operate and fully service it,” Loucks said.

Answering the Blunt Demand; Hash-Handling, Packaging Are Next

It didn’t take long for customers to demand a machine that could roll bigger joints, Loucks said. The BlackBird XXL model works much the same way as its predecessor, but producing bigger blunts with wood and glass tips. Additionally, an automated cigar-band labeler was integrated mid-roll. “This was a response to customers asking for blunts,” Loucks said. “Filling this from the top would be extremely difficult,” he said.

When asked what’s next, Loucks said his customers are asking for a “hash hole,” which is a joint infused with a piece of hashish nestled within, so he is working on developing a modular add-on to handle the sticky hash-infused joints. “Hash is very sticky; it’s best hand-rolled now,” he said. “I’m close; I just need a modular attachment to lay a hash worm on the scale,” he said.

Packaging automation is another upcoming priority for RollPros. “We do 1,000 joints an hour, but four people pack by hand,” he said. “Automating packaging is next.”