Eliminating Downtime in Robotic Prescription Dispensing Systems

In the demanding field of robotic prescription dispensing, reliability is the primary engineering constraint. ScriptPro designs robotic systems for retail pharmacies and secure government facilities—environments where machine downtime can delay critical patient medication or disrupt chain-of-custody tracking for controlled substances.

Domenic Corrado, Electrical Engineering Manager at ScriptPro, identified a recurring failure point in the company’s motion systems: the brushed DC motors. While functional initially, the carbon brushes used in the mechanical commutation of the motors, wore down over time, leading to machine failures or degraded performance.

"Originally, we used brushed DC motors, but after a year, field engineers had to replace the brushes," Domenic explains. "The motors never performed like new again."

To eliminate this maintenance burden, ScriptPro transitioned to Teknic’s Hudson brushless servo motors. The move to a brushless architecture removed the primary wear component, but the Hudson line offered further reliability assurances critical for medical-grade robotics.

Every Hudson motor undergoes Highly Accelerated Stress Screening (HASS) to verify insulation and assembly integrity before shipment. Additionally, the motors utilize oversized, sealed bearings designed to handle large radial loads—a crucial feature for the belt-driven conveyor applications in ScriptPro’s systems.

"We are extremely happy with the motors we've been getting from Teknic because they just don't fail," says Domenic.

Beyond reliability, the application presented a mechanical layout challenge. The robots required motors with high torque to move heavy gantries and conveyors, but the machine chassis offered limited axial space. Alternative suppliers could only meet the torque requirements by adding gearheads, which extended the motor length beyond the allowable envelope.

Teknic solved this density problem by utilizing sintered Neodymium-Iron-Boron magnets rather than weaker plastic-bonded alternatives, and optimizing the stator geometry using 3D finite element analysis (FEA). This design allows for maximum winding fill and torque generation in a compact form factor.

"We needed a physically bigger diameter but a short length," Domenic notes. "Your motors have oodles of torque."

ScriptPro now integrates these motors into critical axes across multiple product lines:

• CRS and SP Systems: The Hudson M-3422 drives the outfeed conveyors on these vial-filling robots, providing consistent torque to manage varying loads.

• SRS (Storage and Retrieval System): The Hudson M-3441 powers the X-axis—a large gantry mounted on a slewing bearing. This counting robot is frequently used for narcotics security in VA hospitals.

The torque density was demonstrated vividly during testing. Domenic describes installing a motor in a test unit: "I once put a motor in a decommissioned cabinet and it had so much torque it was 'oil canning' the side of the control center because there weren't enough stiffeners."

Logistics also played a vital role in the partnership. ScriptPro faces unpredictable demand cycles, where customers may suddenly order multiple robotic systems requiring rapid installation. Teknic’s US-based manufacturing allows for quick delivery, enabling ScriptPro to meet these tight deadlines without carrying excessive inventory.

"One reason I'm pushing for Hudson motors [on new machine axes] is that your turnaround time is fantastic," Domenic notes.

The combination of robust hardware and reliable support has solidified the relationship. "You're very responsive and your product is great," Domenic concludes.