Angle Detection System

Quality in Coin Manufacturing

Mints and manufacturers alike follow a detailed and highly accurate coining process to produce a high volume of new coins. The process involves using a CNC Machine Grinder to key coin dies that are used later during the stamping procedure. The CNC Machine must grind the die with high angular precision to ensure that it can be inserted with accuracy into the press. Mints can stand to lose a lot of time, money and efforts on consequent waste from improper coin stamping and must ultimately produce consistent coins with consistent quality.

A local mint ran into this exact issue during coin production, so Artemis Vision asked critical questions in determining the most successful vision system to solve the problem. 

  • How can we eliminate waste? 
  • How can we save money, and integrate a more preventative solution? 

The team developed and designed what is known as the Angle Detection System which meets coining challenges by pairing with the client’s existing CNC Machine to assist in identifying accurate angles on the die before keying. There is only a small margin of error allowed for the stamping process, and the dies must be orientated correctly to ensure that there are no defects produced on the final product. The Angle Detection System is capable of identifying and correcting those misalignment errors that the operator or grinder may not be successful in catching, which leads to faster production times and a more confident manufacturing process.

Artemis Vision’s Die Angle Detection System

At the coin mint plant, a variety of coin die models are keyed in with the facility’s grinder before being sent to the coin pressing machine to produce much more batches of the same coin.

The Angle Detection System’s unit is a fully automated alignment procedure. The unit illuminates the shiny die face and captures high-resolution images that are sent to the PC. Coin die angles are calculated via Artemis Vision’s proprietary software which then sends motion commands to the grinder to align the die. The system utilizes only industry-leading hardware such as the FLIR Grasshopper3 2.3 MP Mono GigE Vision camera because of its reliability, high dynamic range feature, and GigE interface capabilities. Additional hardware includes a machine vision lens, lens extender, and light diffuser. By combining software from Microscan and Point Grey for imaging capture and processing, Artemis Vision has created an intuitive and turnkey system that integrates seamlessly into current operations.

Customizable features allow operators to set angular points on the coin die models with high accuracy for more consistent keying every time. The intuitive program also provides feedback on the images of expected angles, reported angles and angle errors, and can retrieve previously saved models to save time. Mints can trust in the Angle Detection System to serve them well since it has an angular accuracy of less than 1/10 of a degree and can accommodate dies up to 40.6 mm, which makes it accurate enough for most coinage operations.

The Angle Detection System’s footprint size measures to only 5” x 12” and is implemented easily into current operations to run reliably for continuous 24/7 operations. The unit can also be used in harsh and wet environments, and for extra ease, involves very little maintenance by the operator over time. 

Mints and other coin manufacturers must produce coins of high quality and with as little defects as possible. Catching and fixing errors in the die alignment and keying process, prior to pressing, allows for more accountability, and saves the manufacturer time and money in correcting post-production errors.