Smart Cash Handling Kiosk Development

We are developing a self-service kiosk dedicated to safe, accurate and reliable cash handling. The scope of this project is strictly machine development, electronics, embedded firmware and mechanical engineering. We do not want to use Raspberry Pi, ESP32, Arduino, an embedded PC or similar development-board solutions as the main controller. The objective is to design and develop our own complete machine architecture, including a custom controller PCB, embedded firmware, cash-handling mechanisms, sensors, actuators, power electronics and mechanical enclosure. Core Workflow The machine will allow a customer to: Insert banknotes and coins. Detect and identify every deposited cash item. Maintain and display the running deposited amount. Compare the deposited amount with the required bill amount. Once the required amount is reached, retain the exact required amount. Automatically return any excess amount as change. Verify that the correct change has been dispensed. Complete and record the transaction with a full audit trail. Main Machine Requirements The machine should include, as applicable: Banknote validator/acceptor Banknote escrow mechanism Banknote stacker or secure storage Coin acceptor Coin escrow mechanism Coin hoppers/recyclers for change dispensing Banknote recycling/change mechanism where required Secure cash vault/cashbox Optical and position sensors Hopper full/empty sensors Jam detection Door/tamper detection Motor and solenoid control Custom power supply and protection circuitry Custom main controller PCB Service/maintenance interface Display/user-interface hardware as required Proven commercial cash-handling devices may be used where appropriate, but they must be integrated into our own controller architecture. MDB, ccTalk, RS-232, RS-485, CAN or other suitable industrial interfaces may be considered depending on the selected devices. Custom Controller The project must include the design of a dedicated controller board for the machine. The controller should be based on a proven industrial microcontroller rather than Raspberry Pi, ESP32 or another general-purpose development platform. The custom controller should provide: Real-time control of all cash-handling devices Sensor monitoring Motor/solenoid control Hardware watchdog Brownout/power-failure protection Non-volatile transaction/event storage Real-time clock Fault and alarm handling Secure transaction state management Communication interfaces required by the cash devices Service/diagnostic interface Expansion capability for future hardware The controller should remain capable of safely managing a transaction even if an external display, communication interface or other non-critical component fails. Transaction Control The firmware should implement a robust transaction state machine such as: IDLE → ACCEPTING CASH → ESCROW → AMOUNT REACHED → CALCULATE CHANGE → DISPENSE CHANGE → VERIFY → COMMIT TRANSACTION → COMPLETE The system must safely handle: Underpayment Exact payment Overpayment Invalid notes Rejected coins Coin jams Note jams Hopper empty conditions Hopper full conditions Sensor faults Door opening Power interruption Communication failure with a cash device Incomplete dispensing Recovery after restart The system must never mark a transaction as completed until the physical cash movement has been verified. Change Dispensing The change-return mechanism is a critical part of the machine. The controller should calculate the required change and determine the appropriate combination of available denominations. The system should: Track the inventory of every denomination. Select an appropriate dispensing combination. Detect each successfully dispensed item. Detect failed dispensing, jams and empty hoppers. Recalculate or safely abort when the required change cannot be dispensed. Verify the final dispensed amount. Prevent incorrect completion of a transaction. The design should support future expansion to additional denominations where practical. Mechanical Engineering The project must include complete mechanical engineering of the cash-handling system. This includes: Banknote insertion and transport path Coin insertion and transport path Escrow mechanisms Hopper mounting Cashbox/vault Motors and actuators Sensor mounting Anti-jam mechanisms Anti-fishing and anti-tamper mechanisms Service access Locking mechanisms Internal cable routing Thermal and ventilation considerations Complete kiosk enclosure The design should make cash-handling components accessible for maintenance and replacement without requiring unnecessary disassembly of the entire machine. Electrical Engineering The electrical design should include: AC/DC power architecture Appropriate voltage rails Over-current protection Short-circuit protection Fuse/protection strategy Motor and solenoid drivers Sensor interfaces Isolated communication interfaces where required EMI/EMC considerations Grounding strategy Power-loss detection Emergency/service isolation Connector and wiring specifications Separate power domains should be considered for high-current motors/solenoids and sensitive digital electronics. Firmware The project includes the embedded firmware required to operate the complete machine. Firmware should provide: Cash-device communication Sensor monitoring Actuator control Transaction management Cash counting Change calculation Change dispensing Fault detection Jam detection Power-loss recovery Transaction logging Device health monitoring Maintenance/diagnostic functions Error codes and service information Firmware should preferably be written in C/C++ or another appropriate embedded language suitable for a production industrial controller. Audit and Transaction Records Every transaction should generate a detailed record containing, where applicable: Transaction ID Date/time Individual denominations accepted Total amount deposited Required amount Amount retained Change amount Individual denominations dispensed Device status Errors/faults Jam events Transaction completion status The controller should maintain sufficient non-volatile records to recover safely from unexpected power interruption. Testing and Validation The prototype must undergo systematic testing of: Individual note acceptance Individual coin acceptance Multiple-denomination deposits Exact payment Underpayment Overpayment Change dispensing Empty hopper conditions Full hopper conditions Jam conditions Sensor failures Communication failures Power interruption during transaction Repeated transactions Long-duration operation Cash reconciliation The target is 99.8% or better cash-item recognition/counting accuracy, subject to clearly defined test conditions and statistically meaningful testing. Deposits must reconcile precisely with the machine's internal transaction records. Change dispensing should meet the agreed denomination and quantity tolerance, with physical sensors confirming successful dispensing. Prototype Deliverables The expected deliverables are: Complete system architecture Cash-handling component selection Component BOM with manufacturer and sourcing information Interface specifications for all cash devices Electrical schematics Custom controller PCB design PCB fabrication files PCB assembly documentation Mechanical CAD drawings Complete cash-path design Enclosure and vault design Wiring diagrams Embedded firmware Transaction and change-control logic Diagnostic and service functionality Prototype machine assembly Functional testing report Reliability/endurance testing report Installation and maintenance documentation Manufacturing documentation for future production Important Scope Clarification This is not a Raspberry Pi/ESP32 integration project. We are looking for a team/company capable of developing the actual machine from the hardware level, including: Mechanical design + custom electronics + custom controller PCB + embedded firmware + cash-handling integration + sensors + actuators + testing. A proven industrial microcontroller may be used as the processing core, but the controller electronics and firmware should be designed specifically for this machine. General-purpose Raspberry Pi, ESP32, Arduino or similar development boards should not be used as the final production controller. We are primarily interested in engineers/companies with hands-on experience in cash-handling machines, payment terminals, vending machines, kiosks, bill validators, coin acceptors, hoppers, escrow mechanisms, industrial embedded systems and electromechanical product development. Please provide details of similar machines or payment/cash-handling equipment you have developed, your proposed controller and cash-handling architecture, recommended components, prototype development timeline, testing approach and estimated development cost.

Project ID: 40644292