结论：按「非破坏—轻微改变—破坏」的顺序排，样机数量能明显减少
轮椅的检测项目多，如果每个项目都用新样机，样机数量会很大——而样机是有成本的，特别是定制或小批量产品。
合理安排顺序，同一台样机可以完成相当多的项目。 原则是：
先做完全不改变样机状态的项目。
再做可能轻微改变状态的项目。
最后做破坏性或明显改变状态的项目。
这个顺序下，前面的项目不影响后面，样机可以连续使用。
项目的破坏性分级
| 级别 | 项目 | 对后续的影响 |
|---|---|---|
| 无影响 | 尺寸、质量、外观、标识 | 无 |
| 无影响 | 稳定性（静态） | 无 |
| 轻微 | 功能测试、调节操作 | 轻微磨损 |
| 轻微 | 电气安全、EMC | 基本无 |
| 中等 | 制动、推行、爬坡 | 轮胎和制动件磨损 |
| 中等 | 环境试验（温湿度） | 可能有累积影响 |
| 较大 | 疲劳与耐久 | 明显的磨损和可能的变形 |
| 破坏 | 静态强度（加载至失效） | 样机损坏 |
| 破坏 | 跌落、冲击 | 可能损坏 |
| 破坏 | 阻燃、材料测试 | 取样破坏 |
「环境试验」的位置值得斟酌。 它本身不破坏样机，但温湿度循环可能对材料有累积影响，建议放在机械耐久之前、静态强度之后，或者用单独的样机。
推荐的顺序
第一阶段：完全非破坏。
尺寸与质量测量、外观检查、标识核对、各部件的核对、静态稳定性。
第二阶段：功能与电气。
各功能的操作验证、调节机构的操作、电气安全、电磁兼容。
第三阶段：性能测试。
制动性能、推行力、速度与爬坡（电动）、续航（电动）、越障。
第四阶段：环境试验。
温度、湿度、防水防尘。之后复测关键功能。
第五阶段：耐久试验。
滚筒试验、折叠循环、调节循环。之后复测稳定性、制动、功能。
第六阶段：破坏性试验。
静态强度加载至失效、跌落、冲击。
「耐久后复测」这一步很有价值，它得到的是使用一段时间后的性能数据，而这在其他顺序下需要额外的样机。
可以共用样机的组合
第一到第三阶段的全部项目。 基本可以用同一台样机。
第四阶段可以接续。 环境试验后样机通常仍可用。
第五阶段可以接续。 耐久后样机有磨损但通常未损坏。
第六阶段是终点。 破坏性试验之后样机不再可用。
所以理论上一台样机可以从第一阶段做到第六阶段，这是样机利用率较高的安排。
需要单独样机的情形
材料取样。 阻燃、生物相容性、材料成分需要破坏取样，可以从损坏的样机上取，也可以用单独的材料样品。
多个破坏性项目。 静态强度的不同加载点、不同方向的跌落，可能需要多台。
对比测试。 需要未经历前序试验的样机作对照。
平行进行。 为缩短周期，某些项目可以并行，需要多台。
不同配置。 覆盖不同型号或配置时。
「为缩短周期而并行」是实际的权衡。 用一台样机串行做完所有项目，样机省了但周期长；多台并行周期短但样机多。按项目的紧迫程度决定。
顺序安排的注意点
记录样机的经历。 每个项目做完后记录样机的状态和经历的试验。
关键项目的数据要在合适的状态下取得。 比如稳定性数据应当在样机未变形时测。
磨损的影响要考虑。 制动测试后轮胎和制动件磨损，如果后面还要测制动相关的项目，数据会受影响。
避免不可逆的改变。 某些拆装可能不可逆。
复测的安排。 哪些项目需要在某个阶段后复测。
「记录样机的经历」在报告中有意义，因为读报告的人需要知道某个数据是在什么状态的样机上测得的。
与委托方的沟通
样机数量的确认。 根据项目清单确定需要几台。
顺序的确认。 是优先省样机还是优先缩短周期。
破坏性项目的确认。 哪些样机会损坏、损坏后怎么处理。
样机的退回。 未损坏的样机是否退回。
建议在委托时就明确这几点，避免测试中才发现样机不够或者样机被破坏而委托方没有预期。
周期与成本的权衡
| 策略 | 样机数量 | 周期 | 适用 |
|---|---|---|---|
| 完全串行 | 少 | 长 | 样机贵、时间充裕 |
| 部分并行 | 中 | 中 | 多数情形 |
| 完全并行 | 多 | 短 | 时间紧迫 |
多数情况下部分并行是合理的选择 ——把周期长的项目（耐久、环境）提前启动并单独用样机，其余项目串行。
与后续复测的关系
如果预期会有整改和复测，样机安排要留余量：整改后需要新样机复测；可能需要对比原样机与整改后的样机；以及复测的项目范围可能扩大。
建议在首次送检时就考虑复测的可能，预留一定的样机或者确认后续能快速补充。
样机准备的实际建议
按项目清单倒推数量。 先确定项目，再算需要几台。
留有余量。 试验中可能出现意外损坏。
考虑复测。 整改后的复测需要样机。
样机的一致性。 多台样机应当来自同一批次。
保留对照样机。 一台不参与试验，作为对照。
「保留对照样机」在需要对比时很有用，比如判断某个变化是试验造成的还是样机本来就有的。
试验中的异常处理
样机在试验中意外损坏时：记录损坏的情形与阶段；判断是产品问题还是试验操作问题；与委托方沟通后续安排；以及判断已完成项目的数据是否仍然有效。
「已完成项目的数据是否有效」要判断，因为后面的损坏不一定影响前面已经测得的数据。
我们的做法
承接轮椅委托时，我们会根据项目清单给出建议的样机数量和试验顺序，并说明哪些项目会损坏样机。
如果委托方希望尽量节省样机，我们会按串行顺序安排；如果周期紧，我们会建议增加样机并行进行。 这个权衡由委托方根据实际情况决定。
耐久后的复测我们通常建议加上，因为它的边际成本很低（样机已经在手上），但得到的数据反映了使用一段时间后的性能，价值明显。
如果你在规划轮椅的送检，想确定样机数量和顺序，可以把项目清单发过来一起讨论，或者直接联系：132 4819 8029。检测能力见服务介绍，产品分类见手动轮椅检测与电动轮椅检测，案例见案例。
English version
Conclusion. Wheelchair testing involves many items, and using a fresh sample for each would require a great many samples, which cost money, particularly for custom or low-volume products. Arranged sensibly, one sample can complete a considerable number of items. The principle is to perform items that do not change the sample's condition first, then items that change it slightly, and finally destructive items or those that change it markedly. In that order, earlier items do not affect later ones and the sample serves continuously.
Grading items by destructiveness. No effect: dimensions, mass, appearance and marking, and static stability. Slight effect: functional testing and adjustment operation, causing minor wear, and electrical safety and electromagnetic compatibility, with essentially none. Moderate effect: braking, pushing and gradient testing, wearing tyres and brake components, and environmental testing of temperature and humidity, with possible cumulative effects. Substantial effect: fatigue and durability, producing noticeable wear and possible deformation. Destructive: static strength loaded to failure, destroying the sample; drop and impact, possibly damaging it; and flammability and material testing, destroying sampled material. Environmental testing deserves thought about placement: it does not destroy the sample while temperature and humidity cycling may affect materials cumulatively, so place it before mechanical durability and after static strength, or use a separate sample.
Recommended sequence. First stage, wholly non-destructive: dimensional and mass measurement, appearance inspection, marking verification, component checking and static stability. Second stage, function and electrical: functional verification, adjustment mechanism operation, electrical safety and electromagnetic compatibility. Third stage, performance: braking performance, push force, speed and gradient for powered chairs, range for powered chairs, and obstacle negotiation. Fourth stage, environmental: temperature, humidity and ingress protection, followed by re-verification of key functions. Fifth stage, durability: drum testing, folding cycles and adjustment cycles, followed by re-measurement of stability, braking and function. Sixth stage, destructive: static strength to failure, drop and impact. The re-measurement after durability is particularly valuable, producing performance data for a product after a period of use, which other sequences would require additional samples to obtain.
Items that can share a sample. Everything in the first three stages can generally use one sample. The fourth stage can follow, since the sample usually remains usable after environmental testing. The fifth can follow, since durability wears the sample without usually destroying it. And the sixth is the end point, after which the sample is no longer usable. In principle, therefore, one sample can run from the first stage to the sixth, which is a high-utilisation arrangement.
When separate samples are needed. Material sampling for flammability, biocompatibility and composition requires destructive sampling, which can come from a damaged sample or from separate material specimens. Multiple destructive items, such as static strength at different loading points and drops in different orientations, may require several samples. Comparative testing needs samples that have not been through earlier tests. Parallel working shortens the schedule and needs several samples. And different configurations need samples covering each model or configuration. Parallel working for schedule is a real trade-off: running everything serially on one sample saves samples and lengthens the schedule, while parallel working shortens it at the cost of more samples. Decide by the urgency of the items.
Points in sequencing. Record the sample's history, noting its condition and the tests performed after each item. Obtain key data in the appropriate condition, measuring stability, for instance, before any deformation. Consider the effect of wear, since tyres and brake components wear during braking testing and later braking-related items would be affected. Avoid irreversible changes, since some disassembly cannot be undone. And plan re-measurement, deciding which items are repeated after which stage. Recording the sample's history matters in the report, because a reader needs to know the condition of the sample when a given measurement was made.
Discussing with the client. Confirm the number of samples from the item list. Confirm the sequence, whether saving samples or shortening the schedule takes priority. Confirm destructive items, covering which samples will be damaged and how that is handled. And confirm sample return for those undamaged. Settle these when commissioning, to avoid discovering mid-testing that samples are insufficient or that a sample has been destroyed without the client expecting it.
How we handle it. For wheelchair work we propose a sample quantity and test sequence from the item list and state which items will damage samples. Where a client wants to minimise samples we arrange items serially; where the schedule is tight we suggest additional samples and parallel working. That trade-off is the client's to make. We usually suggest adding post-durability re-measurement, since its marginal cost is low, the sample being already in hand, while the data reflect performance after a period of use and are clearly valuable.
Send us the item list and we will work out sample quantity and sequence. Phone or WeChat: +86 132 4819 8029.