Trial production of non-standard robot components: Prototype to small batch, CNC process curing needs to do these things well

Engineers who work on robot hardware projects often encounter the following practical dilemma: the CNC machining prototype of robot parts is assembled smoothly, but when non-standard parts enter the small batch stage of trial production, there may be hole drift, deformation of thin-walled parts,  inconsistent tightness of parts in the same batch. Many people's first reaction is to blame the inadequate production management of the processing plant. Upon reviewing a large number of outsourcing projects for precision components in Shenzhen, it can be seen that during the prototype stage, relying on experienced technicians for individual machine adjustment  manual repair of certain parts, the samples can be debugged  qualified; But this model, which relies on personal experience, cannot be directly replicated for small-scale production of tens  hundreds of pieces. The conversion of prototypes to small batches is  simply about increasing the number of orders, the core is to achieve replicability of the entire processing technology. The process lacks document solidification, complete first article inspection,  control over drawing version changes. Even if the prototype is perfect, it is still prone to collapse in the small batch stage.

Trial production of non-standard robot components: Prototype to small batch, CNC process curing needs to do these things well

The non-standard components of humanoid robots  special equipment are mostly thin-walled shaped shells  complex structural components such as pin axis connecting rods. The prototype stage produces a small number of items,  engineers  process personnel follow up throughout the process. Any deviations can be filed  compensated on-site, making it easy to obtain qualified samples for assembly. However, this "relying on craftsmanship to support the bottom line" model cannot be directly transferred to the small-scale trial production of non-standard components. Once the manual piece by piece correction is lost, the hidden dangers that are covered up during the sampling stage, such as fluctuations in cutting parameters, fixture positioning deviation, tool wear,  confusion in drawing versions, will erupt in a concentrated manner, resulting in increased dispersion of parts, assembly lag,  directly slowing down the NPI progress of the entire machine.

1、 Prototype wins in rapid validation, weakness lies in process that cannot be replicated

Many precision component outsourcing projects in Shenzhen have had normal prototype stages; Entering the small-scale trial production of non-standard components, the scrap rate remains high. The root cause is  the insufficient precision of the machine tool hardware, but rather the pursuit of submitting qualified samples during the prototype stage, without synchronously depositing reusable CNC process solidification files. The manual research  temporary adjustment operations were  recorded in the process documents,  after changing shifts  operators, the entire experience was directly lost, resulting in batch size dispersion.

2、 CNC process solidification: transforming the "implicit craftsmanship" of the prototype  standardized process documents

The primary task in CNC machining of robot parts,  prototype to small-scale trial production, is to document the entire process of sample verification  maturity. A complete process card needs to clarify: process route, selection of processing equipment, fixture scheme, tool list, cutting parameters for each process, allocation of blank allowance,  inspection nodes for each process. Implement the same set of standards for different operators  shifts.

Several key points that are easily overlooked in the trial production of non-standard robot components:

1. The clamping scheme should be oriented towards batch repeatability. The prototype can be manually aligned in half an hour; During the small batch stage, specialized  quick change fixtures should be installed to lock a unified positioning reference  reduce positioning deviation caused by manual clamping.

2. Establish a tool life control mechanism. All prototypes use brand new cutting tools; Continuous small batch processing will gradually wear out the cutting tools. If there are no set tool change nodes  size compensation rules, the second half of the parts will quietly exceed the tolerance.

3. Standardization of raw materials. Clearly define the material grade  heat treatment status, try to use the same batch of raw materials for production,  require the supplier to provide material certification to avoid deformation fluctuations caused by material batch differences.

4. The prototype stage requires a mass production rehearsal. In the later stage of the prototype, the tooling  cutting parameters that will be used in subsequent small batches will be used to continuously process several pieces, exposing the risks of tooling vibration, thermal deformation, etc. in advance. Resolving minor issues in a few sample stages is much better than rectifying them after mass production.

Prototype wins in rapid validation, weakness lies in process that cannot be replicated

5 sentences you can ask directly for the evaluation of prototype to small batch outsourcing

1. For non-standard robot components, are complete  reusable CNC process cards synchronously output during the prototype stage? ”

2. How to control the tooling, tool life,  cutting parameters for small-scale production

3. What kind of ECN change process is used for modifying drawing versions,  how can we prevent the mixing of old  new versions? ”

4. For each batch of production, is the FAI first piece full-size inspection carried out  records of actual measurement deviations are kept? ”

5. If the prototype is converted to a small batch  the processing plant is changed, how will the process documents  testing standards be handed over

If the outsourcing service provider only emphasizes that the prototype samples are made beautifully  cannot explain the implementation process of process solidification, version control,  first article inspection, then the risk of quality loss of control is high after the trial production of non-standard components enters small batches.

3、 FAI first article, process sampling, ECN version control,  three lines of defense for small batch quality

The process documents are complete  require supporting management mechanisms to ensure their implementation.

1. FAI First Article Inspection: After each batch of production, tool change,  tooling change, the first part must undergo full-size  key feature testing  be confirmed to be qualified before production can continue. It is prohibited to produce directly without making the first piece, in order to avoid programming  clamping errors in the entire batch of parts.

2. Process sampling  key dimension trend recording. Small batches do  necessarily require complex  complete SPC statistics, but for key components such as robot joints  shells, sampling should be conducted at production intervals to record the actual measurement deviation of key dimensions DEV. Once the data drifts towards the tolerance boundary, parameter compensation can be done in advance instead of selecting defective products after all processing is completed.

3. Strict ECN drawing version change management. Robot development iterations are frequent,  drawing changes are common, but changes cannot be transmitted orally  through WeChat. All modifications shall be made through formal ECN change orders, with clear version numbers indicated on the drawings; Old drawings  old work in progress should be isolated  inspected to prevent mixed production of old  new versions.

The project risk of multi supplier collaboration is higher. If CNC machining of the same robot part is assigned to multiple outsourcing companies, it is necessary to unify the process standards  testing benchmarks. Otherwise, even if the parts produced by each company are individually tested  qualified, there will still be matching problems when assembled together.

FAQ

Q: Will the process solidification during the prototype stage slow down the iteration speed of the robot project?

A: In the short term, it will increase a small amount of review workload, but it can avoid weeks of delays caused by batch rework  version confusion during the small batch stage. The prototype does  have sedimentation process,  when it is converted to a small batch  retested, the overall time will be longer.

Q: Will the processing factory  attach importance to first article inspection when the order is only a few dozen small batches?

A: During the selection stage, FAI first article inspection  version control should be considered as mandatory conditions. Priority should be given to Shenzhen precision parts outsourcing service providers who can fully undertake prototype NPI small  medium batch production, rather than workshops that only do prototype making. The inspection requirements can be written  the technical agreement of the order.

Q: The prototype has been completed, but there is no curing process document at all. Can it be remedied  converted to a small batch?

A: Can be remedied. Collect the final drawings, prototype processing records, assembly  repair status, conduct process review with outsourcing parties, identify risk characteristics, make up process cards, complete a round of first article verification,  then start small-scale production of non-standard component trial production.

Q: Is it necessary to have a full set of SPC statistical control for small-scale trial production?

A: For the trial production of dozens of non-standard robot components, there is no need to pursue complex SPC systems; But key dimensions must be sampled  recorded to monitor the trend of size drift, which is a low-cost way to avoid batch scrapping.

Q: What supporting services can Shenzhen Huiwen Intelligent Manufacturing Technology Co., Ltd. provide for the trial production of small-scale non-standard components  prototypes?

A: We are a design intelligent manufacturing assembly integrated service provider for high-end robots. Can undertake CNC machining of robot parts, supporting complete matching  prototype sampling, DFM review, to small  medium-sized trial production of non-standard components; Synchronize precipitation process cards during the prototype stage, perform FAI first piece inspection last piece comparison,  ECN version change control; The software algorithms  overall assembly of the machine are still led by the customer.

Summary

The trial production of non-standard robot components  the overturning of prototypes in small batches are mostly  due to equipment hardware issues, but rather the direct replication of prototypes relying on manual labor to small-scale production. The combination of CNC process solidification to form executable files, FAI first article inspection to hold the production entrance,  ECN strict control of drawing versions is necessary to transform the qualified samples  stable qualified small batch batches. Collaborate with outsourcing to complete the process review during the final stage of the prototype,  do  wait until mass production to expose risks. Welcome to provide drawing consultation. We can provide 2D drawings, 3D models,  technical requirements to obtain DFM process evaluation  itemized quotations.